Novelty, Adaptive Capacity, and Resilience

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Craig R. Allen

2010-09-01

Full Text Available We present a conceptual framework that explores some of the forces creating innovation and novelty in complex systems. Understanding the sources of variability and novelty may help us better understand complex systems. Understanding complex phenomena such as invasions, migration, and nomadism may provide insight into the structure of ecosystems and other complex systems, and aid our attempts to cope with and mitigate these phenomena, in the case of invasions, and better understand and or predict them. Our model is broadly applicable to ecological theory, including community ecology, resilience, restoration, and policy. Characterizing the link between landscape change and the composition of species communities may help policymakers in their decision-making processes. Understanding how variability is related to system structure, and how that generates novelty, may help us understand how resilience is generated. We suggest that there are three primary opportunities for the generation of novelty into complex systems. These sources of novelty are inherent in the cross-scale structure of complex systems, and are critical for creating adaptive capacity. Novelty originates from the inherent variability present in cross scale structures, within scale reorganization associated with adaptive cycles, and whole-scale transformations resulting from regime shifts. Although speculative, our ideas are grounded in research and observation, and they may provide insight into the evolution of complex systems.

Extending the Generalised Pareto Distribution for Novelty Detection in High-Dimensional Spaces.

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Clifton, David A; Clifton, Lei; Hugueny, Samuel; Tarassenko, Lionel

2014-01-01

Novelty detection involves the construction of a "model of normality", and then classifies test data as being either "normal" or "abnormal" with respect to that model. For this reason, it is often termed one-class classification. The approach is suitable for cases in which examples of "normal" behaviour are commonly available, but in which cases of "abnormal" data are comparatively rare. When performing novelty detection, we are typically most interested in the tails of the normal model, because it is in these tails that a decision boundary between "normal" and "abnormal" areas of data space usually lies. Extreme value statistics provides an appropriate theoretical framework for modelling the tails of univariate (or low-dimensional) distributions, using the generalised Pareto distribution (GPD), which can be demonstrated to be the limiting distribution for data occurring within the tails of most practically-encountered probability distributions. This paper provides an extension of the GPD, allowing the modelling of probability distributions of arbitrarily high dimension, such as occurs when using complex, multimodel, multivariate distributions for performing novelty detection in most real-life cases. We demonstrate our extension to the GPD using examples from patient physiological monitoring, in which we have acquired data from hospital patients in large clinical studies of high-acuity wards, and in which we wish to determine "abnormal" patient data, such that early warning of patient physiological deterioration may be provided.

Novelty, coherence, and Mendeleev's periodic table.

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Schindler, Samuel

2014-03-01

Predictivism is the view that successful predictions of "novel" evidence carry more confirmational weight than accommodations of already known evidence. Novelty, in this context, has traditionally been conceived of as temporal novelty. However temporal predictivism has been criticized for lacking a rationale: why should the time order of theory and evidence matter? Instead, it has been proposed, novelty should be construed in terms of use-novelty, according to which evidence is novel if it was not used in the construction of a theory. Only if evidence is use-novel can it fully support the theory entailing it. As I point out in this paper, the writings of the most influential proponent of use-novelty contain a weaker and a stronger version of use-novelty. However both versions, I argue, are problematic. With regard to the appraisal of Mendeleev' periodic table, the most contentious historical case in the predictivism debate, I argue that temporal predictivism is indeed supported, although in ways not previously appreciated. On the basis of this case, I argue for a form of so-called symptomatic predictivism according to which temporally novel predictions carry more confirmational weight only insofar as they reveal the theory's presumed coherence of facts as real.

How should novelty be valued in science?

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Cohen, Barak A

2017-07-25

Scientists are under increasing pressure to do "novel" research. Here I explore whether there are risks to overemphasizing novelty when deciding what constitutes good science. I review studies from the philosophy of science to help understand how important an explicit emphasis on novelty might be for scientific progress. I also review studies from the sociology of science to anticipate how emphasizing novelty might impact the structure and function of the scientific community. I conclude that placing too much value on novelty could have counterproductive effects on both the rate of progress in science and the organization of the scientific community. I finish by recommending that our current emphasis on novelty be replaced by a renewed emphasis on predictive power as a characteristic of good science.

Improving evolvability of morphologies and controllers of developmental soft-bodied robots with novelty search

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Michał eJoachimczak

2015-12-01

Full Text Available Novelty search is an evolutionary search algorithm based on the superficially contradictory idea that abandoning goal focused fitness function altogether can lead to the discovery of higher fitness solutions. In the course of our work, we have created a biologically inspired artificial development system with the purpose of automatically designing complex morphologies and controllers of multicellular, soft-bodied robots. Our goal is to harness the creative potential of in silico evolution so that it can provide us with novel and efficient designs that are free of any preconceived notions a human designer would have. In order to do so, we strive to allow for the evolution of arbitrary morphologies. Using a fitness-driven search algorithm, the system has been shown to be capable of evolving complex multicellular solutions consisting of hundreds of cells that can walk, run and swim, yet the large space of possible designs makes the search expensive and prone to getting stuck in local minima. In this work, we investigate how a developmental approach to the evolution of robotic designs benefits from abandoning objective fitness function. We discover that novelty search produced significantly better performing solutions. We then discuss the key factors of the success in terms of the phenotypic representation for the novelty search, the deceptive landscape for co-designing morphology/brain, and the complex development-based phenotypic encoding.

Cryptic Genetic Variation in Evolutionary Developmental Genetics

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Annalise B. Paaby

2016-06-01

Full Text Available Evolutionary developmental genetics has traditionally been conducted by two groups: Molecular evolutionists who emphasize divergence between species or higher taxa, and quantitative geneticists who study variation within species. Neither approach really comes to grips with the complexities of evolutionary transitions, particularly in light of the realization from genome-wide association studies that most complex traits fit an infinitesimal architecture, being influenced by thousands of loci. This paper discusses robustness, plasticity and lability, phenomena that we argue potentiate major evolutionary changes and provide a bridge between the conceptual treatments of macro- and micro-evolution. We offer cryptic genetic variation and conditional neutrality as mechanisms by which standing genetic variation can lead to developmental system drift and, sheltered within canalized processes, may facilitate developmental transitions and the evolution of novelty. Synthesis of the two dominant perspectives will require recognition that adaptation, divergence, drift and stability all depend on similar underlying quantitative genetic processes—processes that cannot be fully observed in continuously varying visible traits.

A note on fashion cycles, novelty and conformity

OpenAIRE

Federica Alberti

2013-01-01

We develop a model in which novelty and conformity motivate fashion behavior. Fashion cycles occur if conformity is not too high. The duration of fashion cycles depends on individual-specific conformity, novelty, and the number of available styles. The use of individual-specific novelty and conformity allows us to also identify fashion leaders.

Ghrelin influences novelty seeking behavior in rodents and men.

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Hansson, Caroline; Shirazi, Rozita H; Näslund, Jakob; Vogel, Heike; Neuber, Corinna; Holm, Göran; Anckarsäter, Henrik; Dickson, Suzanne L; Eriksson, Elias; Skibicka, Karolina P

2012-01-01

Recent discoveries indicate an important role for ghrelin in drug and alcohol reward and an ability of ghrelin to regulate mesolimbic dopamine activity. The role of dopamine in novelty seeking, and the association between this trait and drug and alcohol abuse, led us to hypothesize that ghrelin may influence novelty seeking behavior. To test this possibility we applied several complementary rodent models of novelty seeking behavior, i.e. inescapable novelty-induced locomotor activity (NILA), novelty-induced place preference and novel object exploration, in rats subjected to acute ghrelin receptor (growth hormone secretagogue receptor; GHSR) stimulation or blockade. Furthermore we assessed the possible association between polymorphisms in the genes encoding ghrelin and GHSR and novelty seeking behavior in humans. The rodent studies indicate an important role for ghrelin in a wide range of novelty seeking behaviors. Ghrelin-injected rats exhibited a higher preference for a novel environment and increased novel object exploration. Conversely, those with GHSR blockade drastically reduced their preference for a novel environment and displayed decreased NILA. Importantly, the mesolimbic ventral tegmental area selective GHSR blockade was sufficient to reduce the NILA response indicating that the mesolimbic GHSRs might play an important role in the observed novelty responses. Moreover, in untreated animals, a striking positive correlation between NILA and sucrose reward behavior was detected. Two GHSR single nucleotide polymorphisms (SNPs), rs2948694 and rs495225, were significantly associated with the personality trait novelty seeking, as assessed using the Temperament and Character Inventory (TCI), in human subjects. This study provides the first evidence for a role of ghrelin in novelty seeking behavior in animals and humans, and also points to an association between food reward and novelty seeking in rodents.

The Definition of Novelty in Recommendation System

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Liang Zhang

2013-01-01

Full Text Available With the development of information technology and application of the Internet, People gradually entered the time of information overload from information scarcity. User satisfaction with recommender systems is related not only to how accurately the system recommends but also to how much it supports the user’s decision making. Novelty is one of the important metrics of customer satisfaction. There is an increasing realization in the Recommender Systems (RS field that novelty is fundamental qualities of recommendation effectiveness and added-value. This paper combed research results about definition and algorithm of novel recommendation, and starting from the meaning of "novel", defined novelty of item in recommendation system. Experiment proved using the definition of novelty to recommend can effectively recognize the item that the user is familiar with and ensure certain accuracy.

Expecting the unexpected: the effects of deviance on novelty processing.

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Schomaker, Judith; Roos, Rinske; Meeter, Martijn

2014-04-01

Novelty is often prioritized and detected automatically. It attracts attention-eliciting the orienting response. However, novelty is not a unitary concept, and the extent to which the orienting response is elicited depends on several factors. In the present study we investigated how stimulus novelty, deviance from the context, and complexity of the stimulus context contribute to the anterior N2 and novelty P3 event-related potential components, using the visual novelty oddball paradigm. In the first experiment the novelty P3 was drastically reduced when the stimulus context was complex compared with simple, and in a second experiment when novels were frequent rather than deviant. No such effect was found for the anterior N2, suggesting it is a function of stimulus characteristics, not deviance. In contrast, the novelty P3 depended on deviance and contextual complexity.

Revisiting the Novelty Effect: When Familiarity, Not Novelty, Enhances Memory

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Poppenk, J.; Kohler, S.; Moscovitch, M.

2010-01-01

Reports of superior memory for novel relative to familiar material have figured prominently in recent theories of memory. However, such "novelty effects" are incongruous with long-standing observations that familiar items are remembered better. In 2 experiments, we explored whether this discrepancy was explained by differences in the…

Novelty Categorization Theory

NARCIS (Netherlands)

Förster, J.; Marguc, J.; Gillebaart, M.

2010-01-01

Novelty Categorization Theory (NCT) attempts to predict when people perceive events as novel and how they process novel events across different domains. It is predicted that broad mental categories reduce the perception of an event being novel via inclusion processes, whereas narrow categories

Evolutionary analyses of non-genealogical bonds produced by introgressive descent.

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Bapteste, Eric; Lopez, Philippe; Bouchard, Frédéric; Baquero, Fernando; McInerney, James O; Burian, Richard M

2012-11-06

All evolutionary biologists are familiar with evolutionary units that evolve by vertical descent in a tree-like fashion in single lineages. However, many other kinds of processes contribute to evolutionary diversity. In vertical descent, the genetic material of a particular evolutionary unit is propagated by replication inside its own lineage. In what we call introgressive descent, the genetic material of a particular evolutionary unit propagates into different host structures and is replicated within these host structures. Thus, introgressive descent generates a variety of evolutionary units and leaves recognizable patterns in resemblance networks. We characterize six kinds of evolutionary units, of which five involve mosaic lineages generated by introgressive descent. To facilitate detection of these units in resemblance networks, we introduce terminology based on two notions, P3s (subgraphs of three nodes: A, B, and C) and mosaic P3s, and suggest an apparatus for systematic detection of introgressive descent. Mosaic P3s correspond to a distinct type of evolutionary bond that is orthogonal to the bonds of kinship and genealogy usually examined by evolutionary biologists. We argue that recognition of these evolutionary bonds stimulates radical rethinking of key questions in evolutionary biology (e.g., the relations among evolutionary players in very early phases of evolutionary history, the origin and emergence of novelties, and the production of new lineages). This line of research will expand the study of biological complexity beyond the usual genealogical bonds, revealing additional sources of biodiversity. It provides an important step to a more realistic pluralist treatment of evolutionary complexity.

Novelty-driven Particle Swarm Optimization

DEFF Research Database (Denmark)

Galvao, Diana; Lehman, Joel Anthony; Urbano, Paulo

2015-01-01

Particle Swarm Optimization (PSO) is a well-known population-based optimization algorithm. Most often it is applied to optimize objective-based fitness functions that reward progress towards a desired objective or behavior. As a result, search increasingly focuses on higher-fitness areas. However......, in problems with many local optima, such focus often leads to premature convergence that precludes reaching the intended objective. To remedy this problem in certain types of domains, this paper introduces Novelty-driven Particle Swarm Optimization (NdPSO), which is motivated by the novelty search algorithm...

The availability of novelty sweets within high school localities.

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Aljawad, A; Morgan, M Z; Rees, J S; Fairchild, R

2016-06-10

Background Reducing sugar consumption is a primary focus of current global public health policy. Achieving 5% of total energy from free sugars will be difficult acknowledging the concentration of free sugars in sugar sweetened beverages, confectionery and as hidden sugars in many savoury items. The expansion of the novelty sweet market in the UK has significant implications for children and young adults as they contribute to dental caries, dental erosion and obesity.Objective To identify the most available types of novelty sweets within the high school fringe in Cardiff, UK and to assess their price range and where and how they were displayed in shops.Subjects and methods Shops within a ten minute walking distance around five purposively selected high schools in the Cardiff aea representing different levels of deprivation were visited. Shops in Cardiff city centre and three supermarkets were also visited to identify the most commonly available novelty sweets.Results The ten most popular novelty sweets identified in these scoping visits were (in descending order): Brain Licker, Push Pop, Juicy Drop, Lickedy Lips, Big Baby Pop, Vimto candy spray, Toxic Waste, Tango candy spray, Brain Blasterz Bitz and Mega Mouth candy spray. Novelty sweets were located on low shelves which were accessible to all age-groups in 73% (14 out of 19) of the shops. Novelty sweets were displayed in the checkout area in 37% (seven out of 19) shops. The price of the top ten novelty sweets ranged from 39p to £1.Conclusion A wide range of acidic and sugary novelty sweets were easily accessible and priced within pocket money range. Those personnel involved in delivering dental and wider health education or health promotion need to be aware of recent developments in children's confectionery. The potential effects of these novelty sweets on both general and dental health require further investigation.

Resonator memories and optical novelty filters

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Anderson, Dana Z.; Erle, Marie C.

Optical resonators having holographic elements are potential candidates for storing information that can be accessed through content addressable or associative recall. Closely related to the resonator memory is the optical novelty filter, which can detect the differences between a test object and a set of reference objects. We discuss implementations of these devices using continuous optical media such as photorefractive materials. The discussion is framed in the context of neural network models. There are both formal and qualitative similarities between the resonator memory and optical novelty filter and network models. Mode competition arises in the theory of the resonator memory, much as it does in some network models. We show that the role of the phenomena of "daydreaming" in the real-time programmable optical resonator is very much akin to the role of "unlearning" in neural network memories. The theory of programming the real-time memory for a single mode is given in detail. This leads to a discussion of the optical novelty filter. Experimental results for the resonator memory, the real-time programmable memory, and the optical tracking novelty filter are reviewed. We also point to several issues that need to be addressed in order to implement more formal models of neural networks.

Male rats that differ in novelty exploration demonstrate distinct patterns of sexual behavior

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Cummings, Jennifer A.; Clinton, Sarah M.; Perry, Adam N.; Akil, Huda; Becker, Jill B.

2014-01-01

High versus low novelty exploration predicts a variety of behavioral differences. For example, rats selectively-bred for high novelty exploration (bred High Responders, bHR) exhibit exaggerated aggression, impulsivity, and proclivity to addictive behaviors compared to low novelty-reactive rats (bred Low Responders, bLRs), which are characterized by a high anxiety/depressive-like phenotype. Since bHR/bLR rats exhibit differences in dopaminergic circuitry and differential response to rewarding stimuli (i.e., psychostimulants, food), the present study examined whether they also differ in another key hedonic behavior – sex. Thus, adult bHR/bLR males were given five 30-min opportunities to engage in sexual activity with a receptive female. Sexual behavior and motivation were examined and compared between the groups. The bHR/bLR phenotype affected both sexual motivation and behavior, with bLR males demonstrating reduced motivation for sex compared with bHR males (i.e., fewer animals copulated, longer latency to engage in sex). The bHR males required more intromissions at a faster pace per ejaculation than did bLR males. Thus, neurobiological differences that affect motivation for drugs of abuse, aggression, and impulsivity in rats also affect sexual motivation and performance. PMID:23398441

Evolutionary principles and their practical application

DEFF Research Database (Denmark)

Hendry, A. P.; Kinnison, M. T.; Heino, M.

2011-01-01

Evolutionary principles are now routinely incorporated into medicine and agriculture. Examples include the design of treatments that slow the evolution of resistance by weeds, pests, and pathogens, and the design of breeding programs that maximize crop yield or quality. Evolutionary principles...... are also increasingly incorporated into conservation biology, natural resource management, and environmental science. Examples include the protection of small and isolated populations from inbreeding depression, the identification of key traits involved in adaptation to climate change, the design...... of harvesting regimes that minimize unwanted life-history evolution, and the setting of conservation priorities based on populations, species, or communities that harbor the greatest evolutionary diversity and potential. The adoption of evolutionary principles has proceeded somewhat independently...

Evolutionary principles and their practical application.

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Hendry, Andrew P; Kinnison, Michael T; Heino, Mikko; Day, Troy; Smith, Thomas B; Fitt, Gary; Bergstrom, Carl T; Oakeshott, John; Jørgensen, Peter S; Zalucki, Myron P; Gilchrist, George; Southerton, Simon; Sih, Andrew; Strauss, Sharon; Denison, Robert F; Carroll, Scott P

2011-03-01

Evolutionary principles are now routinely incorporated into medicine and agriculture. Examples include the design of treatments that slow the evolution of resistance by weeds, pests, and pathogens, and the design of breeding programs that maximize crop yield or quality. Evolutionary principles are also increasingly incorporated into conservation biology, natural resource management, and environmental science. Examples include the protection of small and isolated populations from inbreeding depression, the identification of key traits involved in adaptation to climate change, the design of harvesting regimes that minimize unwanted life-history evolution, and the setting of conservation priorities based on populations, species, or communities that harbor the greatest evolutionary diversity and potential. The adoption of evolutionary principles has proceeded somewhat independently in these different fields, even though the underlying fundamental concepts are the same. We explore these fundamental concepts under four main themes: variation, selection, connectivity, and eco-evolutionary dynamics. Within each theme, we present several key evolutionary principles and illustrate their use in addressing applied problems. We hope that the resulting primer of evolutionary concepts and their practical utility helps to advance a unified multidisciplinary field of applied evolutionary biology.

Timing of the evolutionary history of Corallinaceae (Corallinales, Rhodophyta).

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Rösler, Anja; Perfectti, Francisco; Peña, Viviana; Aguirre, Julio; Braga, Juan Carlos

2017-06-01

The temporal dimension of the most recent Corallinaceae (order Corallinales) phylogeny was presented here, based on first occurrence time estimates from the fossil record. Calibration of the molecular clock of the genetic marker SSU entailed a separation of Corallinales from Hapalidiales in the Albian (Early Cretaceous ~105 mya). Neither the calibration nor the fossil record resolved the succession of appearance of the first three emerging subfamilies: Mastophoroideae, Corallinoideae, and Neogoniolithoideae. The development of the tetra/bisporangial conceptacle roofs by filaments surrounding and interspersed among the sporangial initials was an evolutionary novelty emerging at the Cretaceous-Paleogene boundary (~66 mya). This novelty was shared by the subfamilies Hydrolithoideae, Metagoniolithoideae, and Lithophylloideae, which diverged in the early Paleogene. Subclades within the Metagoniolithoideae and Lithophylloideae diversified in the late Oligocene-middle Miocene (~28-12 mya). The most common reef corallinaceans (Hydrolithon, Porolithon, Harveylithon, "Pneophyllum" conicum, and subclades within Lithophylloideae) appeared in this interval in the Indo-Australian Archipelago. © 2017 Phycological Society of America.

Differential housing and novelty response: Protection and risk from locomotor sensitization.

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Garcia, Erik J; Haddon, Tara N; Saucier, Donald A; Cain, Mary E

2017-03-01

High novelty seeking increases the risk for drug experimentation and locomotor sensitization. Locomotor sensitization to psychostimulants is thought to reflect neurological adaptations that promote the transition to compulsive drug taking. Rats reared in enrichment (EC) show less locomotor sensitization when compared to rats reared in isolation (IC) or standard conditions (SC). The current research study was designed to test if novelty response contributed locomotor sensitization and more importantly, if the different housing environments could change the novelty response to protect against the development of locomotor sensitization in both adolescence and adulthood. Experiment 1: rats were tested for their response to novelty using the inescapable novelty test (IEN) and pseudorandomly assigned to enriched (EC), isolated (IC), or standard (SC) housing conditions for 30days. After housing, they were tested with IEN. Rats were then administered amphetamine (0.5mg/kg) or saline and locomotor activity was measured followed by a sensitization test 14days later. Experiment 2: rats were tested in the IEN test early adulthood and given five administrations of amphetamine (0.3mg/kg) or saline and then either stayed in or switched housing environments for 30days. Rats were then re-tested in the IEN test in late adulthood and administered five more injections of their respective treatments and tested for locomotor sensitization. Results indicate that IC and SC increased the response to novelty. EC housing decreased locomotor response to amphetamine and saline, and SC housing increased the locomotor response to amphetamine. Mediation results indicated that the late adult novelty response fully mediates the locomotor response to amphetamine and saline, while the early adulthood novelty response did not. Differential housing changes novelty and amphetamine locomotor response. Novelty response is altered into adulthood and provides evidence that enrichment can be used to reduce

Novelty Detection via Answer Updating

National Research Council Canada - National Science Library

Li, Xiaoyan; Croft, W. B

2004-01-01

.... Specifically, we explore the use of question-answering techniques for novelty detection. New information is defined as new/previously unseen answers to questions representing a user's information need...

Sentence Level Information Patterns for Novelty Detection

Science.gov (United States)

2006-07-01

had new discourse entities that were not found in the growing history list of discourse entities. Eichmann et al [38] considered the number of new...TREC2002: Question Answering and Novelty Tracks”, TREC 2002. [10] D. Eichmann and P. Srinivasan. “Novel Results and Some Answers, The University...D. Eichmann , P. Srinivasan, M. Light, H. Wang, X. Y. Qiu, R. J. Arens, and A. Sehgal, “Experiments in Novelty, Genes and Questions at the

Novelty enhances visual perception.

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Judith Schomaker

Full Text Available The effects of novelty on low-level visual perception were investigated in two experiments using a two-alternative forced-choice tilt detection task. A target, consisting of a Gabor patch, was preceded by a cue that was either a novel or a familiar fractal image. Participants had to indicate whether the Gabor stimulus was vertically oriented or slightly tilted. In the first experiment tilt angle was manipulated; in the second contrast of the Gabor patch was varied. In the first, we found that sensitivity was enhanced after a novel compared to a familiar cue, and in the second we found sensitivity to be enhanced for novel cues in later experimental blocks when participants became more and more familiarized with the familiar cue. These effects were not caused by a shift in the response criterion. This shows for the first time that novel stimuli affect low-level characteristics of perception. We suggest that novelty can elicit a transient attentional response, thereby enhancing perception.

Novelty enhances visual perception.

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Schomaker, Judith; Meeter, Martijn

2012-01-01

The effects of novelty on low-level visual perception were investigated in two experiments using a two-alternative forced-choice tilt detection task. A target, consisting of a Gabor patch, was preceded by a cue that was either a novel or a familiar fractal image. Participants had to indicate whether the Gabor stimulus was vertically oriented or slightly tilted. In the first experiment tilt angle was manipulated; in the second contrast of the Gabor patch was varied. In the first, we found that sensitivity was enhanced after a novel compared to a familiar cue, and in the second we found sensitivity to be enhanced for novel cues in later experimental blocks when participants became more and more familiarized with the familiar cue. These effects were not caused by a shift in the response criterion. This shows for the first time that novel stimuli affect low-level characteristics of perception. We suggest that novelty can elicit a transient attentional response, thereby enhancing perception.

Children's understandings and motivations surrounding novelty sweets: a qualitative study.

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Stewart, Kate F; Fairchild, Ruth M; Jones, Rhiannon J; Hunter, Lindsay; Harris, Carole; Morgan, Maria Z

2013-11-01

Novelty sweets resemble or can be used as toys, are brightly coloured, with striking imagery, and sold at pocket money prices. They encourage regular consumption as packaging can be resealed, leading to prolonged exposure of these high-sugar and low pH products to the oral tissues, risk factors for dental caries and erosion, respectively. To determine how children conceptualise novelty sweets and their motivations for buying and consuming them. Focus groups conducted using a brief schedule of open-ended questions, supported by novelty sweets used as prompts in the latter stages. Participants were school children (aged 9-10) from purposively selected state primary schools in Cardiff, UK. Key findings related to the routine nature of sweet eating; familiarity with and availability of novelty sweets; parental awareness and control; lack of awareness of health consequences; and the overall appeal of novelty sweets. Parents reported vagueness regarding consumption habits and permissiveness about any limits they set may have diluted the concept of treats. Flexible permissiveness to sweet buying applied to sweets of all kinds. Parents' reported lack of familiarity with novelty sweets combined with their low cost, easy availability, high sugar content, and acidity give cause for concern. © 2012 John Wiley & Sons Ltd, BSPD and IAPD.

Comparing novelty of designs from biological-inspiration with those from brainstorming

DEFF Research Database (Denmark)

Keshwani, Sonal; Lenau, Torben Anker; Ahmed-Kristensen, Saeema

2017-01-01

This research aims to understand the significance of biological-analogies in fostering novelty by comparing biological-analogies with other design methods for idea generation. Among other design methods, brainstorming was chosen here as benchmark. Four studies were conducted to compare: (i......) the levels of abstraction at which concepts were ideated using biological inspiration (represented using biocards) with that using traditional brainstorming; and (ii) the novelty of concepts produced by using these two design methods. Concepts produced in these studies were evaluated for levels...... of abstraction at which they were ideated, average novelty, and proportion of high-novelty concepts. Results suggest that concepts generated using biocards were ideated at higher abstraction levels than those using brainstorming, but neither were at the highest abstraction levels. The average novelty of concepts...

A Core Set Based Large Vector-Angular Region and Margin Approach for Novelty Detection

Directory of Open Access Journals (Sweden)

Jiusheng Chen

2016-01-01

Full Text Available A large vector-angular region and margin (LARM approach is presented for novelty detection based on imbalanced data. The key idea is to construct the largest vector-angular region in the feature space to separate normal training patterns; meanwhile, maximize the vector-angular margin between the surface of this optimal vector-angular region and abnormal training patterns. In order to improve the generalization performance of LARM, the vector-angular distribution is optimized by maximizing the vector-angular mean and minimizing the vector-angular variance, which separates the normal and abnormal examples well. However, the inherent computation of quadratic programming (QP solver takes O(n3 training time and at least O(n2 space, which might be computational prohibitive for large scale problems. By (1+ε  and  (1-ε-approximation algorithm, the core set based LARM algorithm is proposed for fast training LARM problem. Experimental results based on imbalanced datasets have validated the favorable efficiency of the proposed approach in novelty detection.

Novelty vs. familiarity principles in preference decisions: Task-context of past experience matters

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Hsin-I eLiao

2011-03-01

Full Text Available Our preferences are shaped by past experience in many ways, but a systematic understanding of the factors is yet to be achieved. For example, studies of the mere exposure effect show that experience with an item leads to increased liking (familiarity preference, but the exact opposite tendency is found in other studies utilizing dishabituation (novelty preference. Recently, it has been found that image category affects whether familiarity or novelty preference emerges from repeated stimulus exposure (Park, Shimojo, and Shimojo, PNAS 2010. Faces elicited familiarity preference, but natural scenes elicited novelty preference. In their task, preference judgments were made throughout all exposures, raising the question of whether the task-context during exposure was involved. We adapt their paradigm, testing if passive exposure or objective judgment task-contexts lead to different results. Results showed that after passive viewing, familiar faces were preferred, but no preference bias in either direction was found with natural scenes, or with geometric figures (control. After exposure during the objective judgment task, familiar faces were preferred, novel natural scenes were preferred, and no preference bias was found with geometric figures. The overall results replicate the segregation of preference biases across object categories and suggest that the preference for familiar faces and novel natural scenes are modulated by task-context memory at different processing levels or selection involvement. Possible underlying mechanisms of the two types of preferences are discussed.

Novelties in Malesian Rosaceae

NARCIS (Netherlands)

Kalkman, C.

1993-01-01

The treatment of the family Rosaceae in Flora Malesiana (Ser. I, vol. 11, 2) will be published in 1993. Since almost all novelties were already published in precursors, only three remain to be formalized: a new variety in Prunus arborea, a new name replacing an illegitimate name in Rubus, and a new

Quantitative analysis of the evolution of novelty in cinema through crowdsourced keywords.

Science.gov (United States)

Sreenivasan, Sameet

2013-09-26

The generation of novelty is central to any creative endeavor. Novelty generation and the relationship between novelty and individual hedonic value have long been subjects of study in social psychology. However, few studies have utilized large-scale datasets to quantitatively investigate these issues. Here we consider the domain of American cinema and explore these questions using a database of films spanning a 70 year period. We use crowdsourced keywords from the Internet Movie Database as a window into the contents of films, and prescribe novelty scores for each film based on occurrence probabilities of individual keywords and keyword-pairs. These scores provide revealing insights into the dynamics of novelty in cinema. We investigate how novelty influences the revenue generated by a film, and find a relationship that resembles the Wundt-Berlyne curve. We also study the statistics of keyword occurrence and the aggregate distribution of keywords over a 100 year period.

A Review of the Relationship between Novelty, Intrinsic Motivation and Reinforcement Learning

Directory of Open Access Journals (Sweden)

Siddique Nazmul

2017-11-01

Full Text Available This paper presents a review on the tri-partite relationship between novelty, intrinsic motivation and reinforcement learning. The paper first presents a literature survey on novelty and the different computational models of novelty detection, with a specific focus on the features of stimuli that trigger a Hedonic value for generating a novelty signal. It then presents an overview of intrinsic motivation and investigations into different models with the aim of exploring deeper co-relationships between specific features of a novelty signal and its effect on intrinsic motivation in producing a reward function. Finally, it presents survey results on reinforcement learning, different models and their functional relationship with intrinsic motivation.

Evolutionary Multiplayer Games

OpenAIRE

Gokhale, Chaitanya S.; Traulsen, Arne

2014-01-01

Evolutionary game theory has become one of the most diverse and far reaching theories in biology. Applications of this theory range from cell dynamics to social evolution. However, many applications make it clear that inherent non-linearities of natural systems need to be taken into account. One way of introducing such non-linearities into evolutionary games is by the inclusion of multiple players. An example is of social dilemmas, where group benefits could e.g.\\ increase less than linear wi...

Quantitative analysis of the evolution of novelty in cinema through crowdsourced keywords

Science.gov (United States)

Sreenivasan, Sameet

2013-01-01

The generation of novelty is central to any creative endeavor. Novelty generation and the relationship between novelty and individual hedonic value have long been subjects of study in social psychology. However, few studies have utilized large-scale datasets to quantitatively investigate these issues. Here we consider the domain of American cinema and explore these questions using a database of films spanning a 70 year period. We use crowdsourced keywords from the Internet Movie Database as a window into the contents of films, and prescribe novelty scores for each film based on occurrence probabilities of individual keywords and keyword-pairs. These scores provide revealing insights into the dynamics of novelty in cinema. We investigate how novelty influences the revenue generated by a film, and find a relationship that resembles the Wundt-Berlyne curve. We also study the statistics of keyword occurrence and the aggregate distribution of keywords over a 100 year period. PMID:24067890

Is it new? Personal and contextual influences on perceptions of novelty and creativity.

Science.gov (United States)

Zhou, Jing; Wang, Xiaoye May; Song, Lynda Jiwen; Wu, Junfeng

2017-02-01

Novelty recognition is the crucial starting point for extracting value from the ideas generated by others. In this paper we develop an associative evaluation account for how personal and contextual factors motivate individuals to perceive novelty and creativity. We report 4 studies that systematically tested hypotheses developed from this perspective. Study 1 (a laboratory experiment) showed that perceivers' regulatory focus, as an experimentally induced state, affected novelty perception. Study 2 (a field study) found that perceivers' promotion focus and prevention focus, measured as chronic traits, each interacted with normative level of novelty and creativity: perceivers who scored higher on promotion focus perceived more novelty (or creativity) in novel (or creative) targets than those who scored lower, whereas perceivers who scored higher on prevention focus perceived less novelty (or creativity) in novel (or creative) targets than those who scored lower. Study 3 (a field study) showed that organizational culture affected the perception of novelty and creativity. Study 4 (a laboratory experiment) found perceiver-by-idea-by-context 3-way interaction effects: for perceivers with prevention focus, the positive relation between normative level of novelty and novelty ratings was weakened in the loss-framing condition versus the gain-framing condition. We discuss implications of the findings for future research and management practice. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Exploration, Novelty, Surprise and Free Energy Minimisation

Directory of Open Access Journals (Sweden)

Philipp eSchwartenbeck

2013-10-01

Full Text Available This paper reviews recent developments under the free energy principle that introduce a normative perspective on classical economic (utilitarian decision-making based on (active Bayesian inference. It has been suggested that the free energy principle precludes novelty and complexity, because it assumes that biological systems – like ourselves - try to minimise the long-term average of surprise to maintain their homeostasis. However, recent formulations show that minimising surprise leads naturally to concepts such as exploration and novelty bonuses. In this approach, agents infer a policy that minimises surprise by minimising the difference (or relative entropy between likely and desired outcomes, which involves both pursuing the goal-state that has the highest expected utility (often termed ‘exploitation’ and visiting a number of different goal-states (‘exploration’. Crucially, the opportunity to visit new states increases the value of the current state. Casting decision-making problems within a variational framework, therefore, predicts that our behaviour is governed by both the entropy and expected utility of future states. This dissolves any dialectic between minimising surprise and exploration or novelty seeking.

Novelty Detection via Topic Modeling in Research Articles

OpenAIRE

S. Sendhilkumar; Nachiyar S Nandhini; G.S. Mahalakshmi

2013-01-01

In today’s world redundancy is the most vital probl em faced in almost all domains. Novelty detection is the identification of new or unknown d ata or signal that a machine learning system is not aware of during training. The problem become s more intense when it comes to “Research Articles”. A method of identifying novelty at each sections of the article is highly required for determining the novel idea proposed in the research ...

Locality in Generic Instance Search from One Example

NARCIS (Netherlands)

Tao, R.; Gavves, E.; Snoek, C.G.M.; Smeulders, A.W.M.

2014-01-01

This paper aims for generic instance search from a single example. Where the state-of-the-art relies on global image representation for the search, we proceed by including locality at all steps of the method. As the first novelty, we consider many boxes per database image as candidate targets to

Full-field particle velocimetry with a photorefractive optical novelty filter

International Nuclear Information System (INIS)

Woerdemann, Mike; Holtmann, Frank; Denz, Cornelia

2008-01-01

We utilize the finite time constant of a photorefractive optical novelty filter microscope to access full-field velocity information of fluid flows on microscopic scales. In contrast to conventional methods such as particle image velocimetry and particle tracking velocimetry, not only image acquisition of the tracer particle field but also evaluation of tracer particle velocities is done all-optically by the novelty filter. We investigate the velocity dependent parameters of two-beam coupling based optical novelty filters and demonstrate calibration and application of a photorefractive velocimetry system. Theoretical and practical limits to the range of accessible velocities are discussed

Novelty enhances visual salience independently of reward in the parietal lobe.

Science.gov (United States)

Foley, Nicholas C; Jangraw, David C; Peck, Christopher; Gottlieb, Jacqueline

2014-06-04

Novelty modulates sensory and reward processes, but it remains unknown how these effects interact, i.e., how the visual effects of novelty are related to its motivational effects. A widespread hypothesis, based on findings that novelty activates reward-related structures, is that all the effects of novelty are explained in terms of reward. According to this idea, a novel stimulus is by default assigned high reward value and hence high salience, but this salience rapidly decreases if the stimulus signals a negative outcome. Here we show that, contrary to this idea, novelty affects visual salience in the monkey lateral intraparietal area (LIP) in ways that are independent of expected reward. Monkeys viewed peripheral visual cues that were novel or familiar (received few or many exposures) and predicted whether the trial will have a positive or a negative outcome--i.e., end in a reward or a lack of reward. We used a saccade-based assay to detect whether the cues automatically attracted or repelled attention from their visual field location. We show that salience--measured in saccades and LIP responses--was enhanced by both novelty and positive reward associations, but these factors were dissociable and habituated on different timescales. The monkeys rapidly recognized that a novel stimulus signaled a negative outcome (and withheld anticipatory licking within the first few presentations), but the salience of that stimulus remained high for multiple subsequent presentations. Therefore, novelty can provide an intrinsic bonus for attention that extends beyond the first presentation and is independent of physical rewards. Copyright © 2014 the authors 0270-6474/14/347947-11$15.00/0.

Chaos Enhanced Differential Evolution in the Task of Evolutionary Control of Selected Set of Discrete Chaotic Systems

Directory of Open Access Journals (Sweden)

Roman Senkerik

2014-01-01

Full Text Available Evolutionary technique differential evolution (DE is used for the evolutionary tuning of controller parameters for the stabilization of set of different chaotic systems. The novelty of the approach is that the selected controlled discrete dissipative chaotic system is used also as the chaotic pseudorandom number generator to drive the mutation and crossover process in the DE. The idea was to utilize the hidden chaotic dynamics in pseudorandom sequences given by chaotic map to help differential evolution algorithm search for the best controller settings for the very same chaotic system. The optimizations were performed for three different chaotic systems, two types of case studies and developed cost functions.

Novelty Detection in and Between Different Modalities

International Nuclear Information System (INIS)

Veflingstad, Henning; Yildirim, Sule

2008-01-01

Our general aim is to reflect the advances in artificial intelligence and cognitive science fields to space exploration studies such that next generation space rovers can benefit from these advances. We believe next generation space rovers can benefit from the studies related to employing conceptual representations in generating structured thought. This way, rovers need not be equipped with all necessary steps of an action plan to execute in space exploration but they can autonomously form representations of their world and reason on them to make intelligent decision. As part of this approach, autonomous novelty detection is an important feature of next generation space rovers. This feature allows a rover to make further decisions about exploring a rock sample more closely or not and on its own. This way, a rover will use less of its time for communication between the earth and itself and more of its time for achieving its assigned tasks in space. In this paper, we propose an artificial neural network based novelty detection mechanism that next generation space rovers can employ as part of their intelligence. We also present an implementation of such a mechanism and present its reliability in detecting novelty

Novelty detection for breast cancer image classification

Science.gov (United States)

Cichosz, Pawel; Jagodziński, Dariusz; Matysiewicz, Mateusz; Neumann, Łukasz; Nowak, Robert M.; Okuniewski, Rafał; Oleszkiewicz, Witold

2016-09-01

Using classification learning algorithms for medical applications may require not only refined model creation techniques and careful unbiased model evaluation, but also detecting the risk of misclassification at the time of model application. This is addressed by novelty detection, which identifies instances for which the training set is not sufficiently representative and for which it may be safer to restrain from classification and request a human expert diagnosis. The paper investigates two techniques for isolated instance identification, based on clustering and one-class support vector machines, which represent two different approaches to multidimensional outlier detection. The prediction quality for isolated instances in breast cancer image data is evaluated using the random forest algorithm and found to be substantially inferior to the prediction quality for non-isolated instances. Each of the two techniques is then used to create a novelty detection model which can be combined with a classification model and used at the time of prediction to detect instances for which the latter cannot be reliably applied. Novelty detection is demonstrated to improve random forest prediction quality and argued to deserve further investigation in medical applications.

Hippocampus duality: Memory and novelty detection are subserved by distinct mechanisms.

Science.gov (United States)

Barbeau, Emmanuel J; Chauvel, Patrick; Moulin, Christopher J A; Regis, Jean; Liégeois-Chauvel, Catherine

2017-04-01

The hippocampus plays a pivotal role both in novelty detection and in long-term memory. The physiological mechanisms underlying these behaviors have yet to be understood in humans. We recorded intracerebral evoked potentials within the hippocampus of epileptic patients (n = 10) during both memory and novelty detection tasks (targets in oddball tasks). We found that memory and detection tasks elicited late local field potentials in the hippocampus during the same period, but of opposite polarity (negative during novelty detection tasks, positive during memory tasks, ∼260-600 ms poststimulus onset, P < 0.05). Critically, these potentials had maximal amplitude on the same contact in the hippocampus for each patient. This pattern did not depend on the task as different types of memory and novelty detection tasks were used. It did not depend on the novelty of the stimulus or the difficulty of the task either. Two different hypotheses are discussed to account for this result: it is either due to the activation of CA1 pyramidal neurons by two different pathways such as the monosynaptic and trisynaptic entorhinal-hippocampus pathways, or to the activation of different neuronal populations, that is, differing either functionally (e.g., novelty/familiarity neurons) or located in different regions of the hippocampus (e.g., CA1/subiculum). In either case, these activities may integrate the activity of two distinct large-scale networks implementing externally or internally oriented, mutually exclusive, brain states. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

The Predictive Power of Evolutionary Biology and the Discovery of Eusociality in the Naked Mole-Rat.

Science.gov (United States)

Braude, Stanton

1997-01-01

Discusses how biologists use evolutionary theory and provides examples of how evolutionary biologists test hypotheses on specific modes of selection and evolution. Presents an example of the successful predictive power of one evolutionary hypothesis. Contains 38 references. (DDR)

Social Novelty Investigation in the Juvenile Rat: Modulation by the μ-Opioid System.

Science.gov (United States)

Smith, C J W; Wilkins, K B; Mogavero, J N; Veenema, A H

2015-10-01

The drive to approach and explore novel conspecifics is inherent to social animals and may promote optimal social functioning. Juvenile animals seek out interactions with novel peers more frequently and find these interactions to be more rewarding than their adult counterparts. In the present study, we aimed to establish a behavioural paradigm to measure social novelty-seeking in juvenile rats and to determine the involvement of the opioid, dopamine, oxytocin and vasopressin systems in this behaviour. To this end, we developed the social novelty preference test to assess the preference of a juvenile rat to investigate a novel over a familiar (cage mate) conspecific. We show that across the juvenile period both male and female rats spend more time investigating a novel conspecific than a cage mate, independent of subject sex or repeated exposure to the test. We hypothesised that brain systems subserving social information processing and social motivation/reward (i.e. the opioid, dopamine, oxytocin, vasopressin systems) might support social novelty preference. To test this, receptor antagonists of each of these systems were administered i.c.v. prior to exposure to the social novelty preference test and, subsequently, to the social preference test, to examine the specificity of these effects. We find that μ-opioid receptor antagonism reduces novel social investigation in both the social novelty preference and social preference tests while leaving the investigation of a cage mate (social novelty preference test) or an object (social preference test) unaffected. In contrast, central blockade of dopamine D2 receptors (with eticlopride), oxytocin receptors (with des-Gly-NH2,d(CH2)5[Tyr(Me)2,Thr4]OVT) or vasopressin V1a receptors [with (CH2)5Tyr(Me2)AVP] failed to alter social novelty preference or social preference. Overall, we have established a new behavioural test to study social novelty-seeking behaviour in the juvenile rat and show that the μ-opioid system

How will climate novelty influence ecological forecasts? Using the Quaternary to assess future reliability.

Science.gov (United States)

Fitzpatrick, Matthew C; Blois, Jessica L; Williams, John W; Nieto-Lugilde, Diego; Maguire, Kaitlin C; Lorenz, David J

2018-03-23

Future climates are projected to be highly novel relative to recent climates. Climate novelty challenges models that correlate ecological patterns to climate variables and then use these relationships to forecast ecological responses to future climate change. Here, we quantify the magnitude and ecological significance of future climate novelty by comparing it to novel climates over the past 21,000 years in North America. We then use relationships between model performance and climate novelty derived from the fossil pollen record from eastern North America to estimate the expected decrease in predictive skill of ecological forecasting models as future climate novelty increases. We show that, in the high emissions scenario (RCP 8.5) and by late 21st century, future climate novelty is similar to or higher than peak levels of climate novelty over the last 21,000 years. The accuracy of ecological forecasting models is projected to decline steadily over the coming decades in response to increasing climate novelty, although models that incorporate co-occurrences among species may retain somewhat higher predictive skill. In addition to quantifying future climate novelty in the context of late Quaternary climate change, this work underscores the challenges of making reliable forecasts to an increasingly novel future, while highlighting the need to assess potential avenues for improvement, such as increased reliance on geological analogs for future novel climates and improving existing models by pooling data through time and incorporating assemblage-level information. © 2018 John Wiley & Sons Ltd.

Learning Behavior Characterizations for Novelty Search

DEFF Research Database (Denmark)

Meyerson, Elliot; Lehman, Joel Anthony; Miikulainen, Risto

2016-01-01

Novelty search and related diversity-driven algorithms provide a promising approach to overcoming deception in complex domains. The behavior characterization (BC) is a critical choice in the application of such algorithms. The BC maps each evaluated individual to a behavior, i.e., some vector...

Human compulsivity: A perspective from evolutionary medicine.

Science.gov (United States)

Stein, Dan J; Hermesh, Haggai; Eilam, David; Segalas, Cosi; Zohar, Joseph; Menchon, Jose; Nesse, Randolph M

2016-05-01

Biological explanations address not only proximal mechanisms (for example, the underlying neurobiology of obsessive-compulsive disorder), but also distal mechanisms (that is, a consideration of how particular neurobiological mechanisms evolved). Evolutionary medicine has emphasized a series of explanations for vulnerability to disease, including constraints, mismatch, and tradeoffs. The current paper will consider compulsive symptoms in obsessive-compulsive and related disorders and behavioral addictions from this evolutionary perspective. It will argue that while obsessive-compulsive disorder (OCD) is typically best conceptualized as a dysfunction, it is theoretically and clinically valuable to understand some symptoms of obsessive-compulsive and related disorders in terms of useful defenses. The symptoms of behavioral addictions can also be conceptualized in evolutionary terms (for example, mismatch), which in turn provides a sound foundation for approaching assessment and intervention. Copyright © 2016. Published by Elsevier B.V.

Benchmarking bio-inspired designs with brainstorming in terms of novelty of design outcomes

DEFF Research Database (Denmark)

Keshwani, Sonal; Lenau, Torben Anker; Ahmed-Kristensen, Saeema

2013-01-01

With the increasing demand of innovative products in the market, there is a need for effective creativity approaches that will support development of creative design outcomes. Most researchers agree that novelty of design concepts is a major element of creativity; design outcomes are more creative...... generated using existing traditional creative problem solving approaches. In this research we have compared the novelty of design concepts produced by using biological analogies with the novelty of design concepts produced by using traditional brainstorming. Results show that there is an increase...... in the percentage of highly novel concepts produced in a design task, as well as the novelty of the concept space, when biological analogies are used over traditional brainstorming....

Taxonomic novelties in African Dracaena (Dracaenaceae)

NARCIS (Netherlands)

Damen, T.H.J.; Burg, van der W.J.; Wiland-Szymańska, J.; Sosef, M.S.M.

2018-01-01

In preparing the treatment of Dracaena for Flore du Gabon and Flore d’Afrique centrale, a relatively high number of taxonomic and nomenclatural novelties were discovered; these are presented here. Within Dracaena five species and one forma are described as new, D. bushii, D. haemanthoides, D.

Evolutionary Fates and Dynamic Functionalization of Young Duplicate Genes in Arabidopsis Genomes.

Science.gov (United States)

Wang, Jun; Tao, Feng; Marowsky, Nicholas C; Fan, Chuanzhu

2016-09-01

Gene duplication is a primary means to generate genomic novelties, playing an essential role in speciation and adaptation. Particularly in plants, a high abundance of duplicate genes has been maintained for significantly long periods of evolutionary time. To address the manner in which young duplicate genes were derived primarily from small-scale gene duplication and preserved in plant genomes and to determine the underlying driving mechanisms, we generated transcriptomes to produce the expression profiles of five tissues in Arabidopsis thaliana and the closely related species Arabidopsis lyrata and Capsella rubella Based on the quantitative analysis metrics, we investigated the evolutionary processes of young duplicate genes in Arabidopsis. We determined that conservation, neofunctionalization, and specialization are three main evolutionary processes for Arabidopsis young duplicate genes. We explicitly demonstrated the dynamic functionalization of duplicate genes along the evolutionary time scale. Upon origination, duplicates tend to maintain their ancestral functions; but as they survive longer, they might be likely to develop distinct and novel functions. The temporal evolutionary processes and functionalization of plant duplicate genes are associated with their ancestral functions, dynamic DNA methylation levels, and histone modification abundances. Furthermore, duplicate genes tend to be initially expressed in pollen and then to gain more interaction partners over time. Altogether, our study provides novel insights into the dynamic retention processes of young duplicate genes in plant genomes. © 2016 American Society of Plant Biologists. All rights reserved.

Tracing the evolutionary origin of vertebrate skeletal tissues: insights from cephalochordate amphioxus.

Science.gov (United States)

Yong, Luok Wen; Yu, Jr-Kai

2016-08-01

Vertebrate mineralized skeletal tissues are widely considered as an evolutionary novelty. Despite the importance of these tissues to the adaptation and radiation of vertebrate animals, the evolutionary origin of vertebrate skeletal tissues remains largely unclear. Cephalochordates (Amphioxus) occupy a key phylogenetic position and can serve as a valuable model for studying the evolution of vertebrate skeletal tissues. Here we summarize recent advances in amphioxus developmental biology and comparative genomics that can help to elucidate the evolutionary origins of the vertebrate skeletal tissues and their underlying developmental gene regulatory networks (GRN). By making comparisons to the developmental studies in vertebrate models and recent discoveries in paleontology and genomics, it becomes evident that the collagen matrix-based connective tissues secreted by the somite-derived cells in amphioxus likely represent the rudimentary skeletal tissues in chordates. We propose that upon the foundation of this collagenous precursor, novel tissue mineralization genes that arose from gene duplications were incorporated into an ancestral mesodermal GRN that makes connective and supporting tissues, leading to the emergence of highly-mineralized skeletal tissues in early vertebrates. Copyright © 2016 Elsevier Ltd. All rights reserved.

Something Old, Something New: A Developmental Transition from Familiarity to Novelty Preferences with Hidden Objects

Science.gov (United States)

Shinskey, Jeanne L.; Munakata, Yuko

2010-01-01

Novelty seeking is viewed as adaptive, and novelty preferences in infancy predict cognitive performance into adulthood. Yet 7-month-olds prefer familiar stimuli to novel ones when searching for hidden objects, in contrast to their strong novelty preferences with visible objects (Shinskey & Munakata, 2005). According to a graded representations…

Evolutionary Fates and Dynamic Functionalization of Young Duplicate Genes in Arabidopsis Genomes1[OPEN

Science.gov (United States)

Wang, Jun; Tao, Feng; Marowsky, Nicholas C.; Fan, Chuanzhu

2016-01-01

Gene duplication is a primary means to generate genomic novelties, playing an essential role in speciation and adaptation. Particularly in plants, a high abundance of duplicate genes has been maintained for significantly long periods of evolutionary time. To address the manner in which young duplicate genes were derived primarily from small-scale gene duplication and preserved in plant genomes and to determine the underlying driving mechanisms, we generated transcriptomes to produce the expression profiles of five tissues in Arabidopsis thaliana and the closely related species Arabidopsis lyrata and Capsella rubella. Based on the quantitative analysis metrics, we investigated the evolutionary processes of young duplicate genes in Arabidopsis. We determined that conservation, neofunctionalization, and specialization are three main evolutionary processes for Arabidopsis young duplicate genes. We explicitly demonstrated the dynamic functionalization of duplicate genes along the evolutionary time scale. Upon origination, duplicates tend to maintain their ancestral functions; but as they survive longer, they might be likely to develop distinct and novel functions. The temporal evolutionary processes and functionalization of plant duplicate genes are associated with their ancestral functions, dynamic DNA methylation levels, and histone modification abundances. Furthermore, duplicate genes tend to be initially expressed in pollen and then to gain more interaction partners over time. Altogether, our study provides novel insights into the dynamic retention processes of young duplicate genes in plant genomes. PMID:27485883

Novelty Detection Classifiers in Weed Mapping: Silybum marianum Detection on UAV Multispectral Images.

Science.gov (United States)

Alexandridis, Thomas K; Tamouridou, Afroditi Alexandra; Pantazi, Xanthoula Eirini; Lagopodi, Anastasia L; Kashefi, Javid; Ovakoglou, Georgios; Polychronos, Vassilios; Moshou, Dimitrios

2017-09-01

In the present study, the detection and mapping of Silybum marianum (L.) Gaertn. weed using novelty detection classifiers is reported. A multispectral camera (green-red-NIR) on board a fixed wing unmanned aerial vehicle (UAV) was employed for obtaining high-resolution images. Four novelty detection classifiers were used to identify S. marianum between other vegetation in a field. The classifiers were One Class Support Vector Machine (OC-SVM), One Class Self-Organizing Maps (OC-SOM), Autoencoders and One Class Principal Component Analysis (OC-PCA). As input features to the novelty detection classifiers, the three spectral bands and texture were used. The S. marianum identification accuracy using OC-SVM reached an overall accuracy of 96%. The results show the feasibility of effective S. marianum mapping by means of novelty detection classifiers acting on multispectral UAV imagery.

Participation in novelty-seeking leisure activities and Alzheimer's disease.

Science.gov (United States)

Fritsch, Thomas; Smyth, Kathleen A; Debanne, Sara M; Petot, Grace J; Friedland, Robert P

2005-09-01

The objective was to study the associations between participation in different types of mentally stimulating leisure activities and status as Alzheimer's disease (AD) case or normal control. Research suggests that participation in leisure activities, especially mentally stimulating activities, is associated with a lower risk for AD. However, no study has yet evaluated associations between AD and different types of mental leisure activities, especially those involving "novelty seeking." The authors used a case-control design to compare participation in activities across the life span in persons with AD and normal controls. Cases (n = 264) were recruited from clinical settings and from the community. Controls were drawn from 2 populations. Control group A members (n = 364) were the friends or neighbors of the cases or members of the same organizations to which the cases belonged. Control group B members (n = 181) were randomly drawn from the community. The 2 control groups did not differ in their responses to most activity questions, so they were combined. Factor analysis of activity questions identified 3 activity factors: (1) novelty seeking; (2) exchange of ideas; and (3) social. Logistic regression analysis indicated that, adjusting for control variables, greater participation in novelty-seeking and exchange-of-ideas activities was significantly associated with decreased odds of AD. The odds of AD were lower among those who more often participated in activities involving exchange of ideas and were lower yet for those who more frequently participated in novelty-seeking activities. We conclude that participation in a variety of mental activities across the life span may lower one's chances of developing AD.

Happier, faster: Developmental changes in the effects of mood and novelty on responses.

Science.gov (United States)

Schomaker, Judith; Rangel-Gomez, Mauricio; Meeter, Martijn

2016-01-01

Positive mood ameliorates several cognitive processes: It can enhance cognitive control, increase flexibility, and promote variety seeking in decision making. These effects of positive mood have been suggested to depend on frontostriatal dopamine, which is also associated with the detection of novelty. This suggests that positive mood could also affect novelty detection. In the present study, children and adults saw either a happy or a neutral movie to induce a positive or neutral mood. After that, they were shown novel and familiar images. On some trials a beep was presented over headphones either at the same time as the image or at a 200-ms stimulus onset asynchrony (SOA), and the task of the participant was to detect these auditory targets. Children were slower in responding than adults. Positive mood, however, speeded responses, especially in children, and induced facilitatory effects of novelty. These effects were consistent with increased arousal. Although effects of novelty were more consistent with an attentional response, in children who had watched a happy movie the novel images evoked a more liberal response criterion, suggestive of increased arousal. This suggests that mood and novelty may affect response behaviour stronger in children than in adults.

Manufacturing Of Novelty Leather From Cattle Stomach

Directory of Open Access Journals (Sweden)

Umme Habiba Bodrun Naher

2015-08-01

Full Text Available Abstract The objective of this study was to investigate the feasibility of turning cattle stomach into novelty leather and then leather product which would add value to end of cattle. Four pieces of green buffalo stomachs were taken through soaking liming deliming pickling tanning neutralization retanning dyeing and fat liquoring operation. Then mechanical operations like drying and staking operations were also done. Some physical tensile strength stitch tear strength and colour rub fastness and chemical chromic oxide content fat content and pH tests were accomplished .The results of physical tests were poor compared to the grain leather as the composition of raw outer coverings of animals and their stomachs are different. The stomach leathers could be used for making coin purse key case bracelet wrist watch belt ear-ring necklace hair band iPod case etc. as novelty leather product item.

Using protistan examples to dispel the myths of intelligent design.

Science.gov (United States)

Farmer, Mark A; Habura, Andrea

2010-01-01

In recent years the teaching of the religiously based philosophy of intelligent design (ID) has been proposed as an alternative to modern evolutionary theory. Advocates of ID are largely motivated by their opposition to naturalistic explanations of biological diversity, in accordance with their goal of challenging the philosophy of scientific materialism. Intelligent design has been embraced by a wide variety of creationists who promote highly questionable claims that purport to show the inadequacy of evolutionary theory, which they consider to be a threat to a theistic worldview. We find that examples from protistan biology are well suited for providing evidence of many key evolutionary concepts, and have often been misrepresented or roundly ignored by ID advocates. These include examples of adaptations and radiations that are said to be statistically impossible, as well as examples of speciation both in the laboratory and as documented in the fossil record. Because many biologists may not be familiar with the richness of the protist evolution dataset or with ID-based criticisms of evolution, we provide examples of current ID arguments and specific protistan counter-examples.

Effects of novelty-reducing preparation on exploratory behavior and cognitive learning in a science museum setting

Science.gov (United States)

Kubota, Carole A.; Olstad, Roger G.

The purpose of this study was to examine the relationships between (a) novelty and exploratory behavior, (b) novelty and cognitive learning, and (c) exploratory behavior and cognitive learning in science museums. Sixty-four sixth-grade public school students participated in a posttest-only control group design. The control group received a treatment designed to decrease the novelty of a field trip setting through a vicarious exposure while the placebo group received an informative but not novelty-reducing treatment. Both groups then visited the field site where they were videotaped. Statistical analyses were conducted on both dependent variables with socioeconomic status and academic achievement as covariates, novelty-reducing preparation as the independent variable, and gender as moderator variable. Exploratory behavior was shown to be positively correlated with cognitive learning. Significant differences were detected for exploratory behavior. For both dependent variables, gender by treatment group interaction was significant with novelty-reducing preparation shown to be highly effective on boys but having no effect on girls.

Modularity of mind and the role of incentive motivation in representing novelty.

Science.gov (United States)

Anselme, Patrick

2012-07-01

Animal and human brains contain a myriad of mental representations that have to be successfully tracked within fractions of a second in a large number of situations. This retrieval process is hard to explain without postulating the massive modularity of cognition. Assuming that the mind is massively modular, it is then necessary to understand how cognitive modules can efficiently represent dynamic environments-in which some modules may have to deal with change-induced novelty and uncertainty. Novelty of a stimulus is a problem for a module when unknown, significant stimuli do not satisfy the module's processing criteria-or domain specificity-and cannot therefore be included in its database. It is suggested that the brain mechanisms of incentive motivation, recruited when faced with novelty and uncertainty, induce transient variations in the domain specificity of cognitive modules in order to allow them to process information they were not prepared to learn. It is hypothesised that the behavioural transitions leading from exploratory activity to habit formation are correlated with (and possibly caused by) the organism's ability to counter novelty-induced uncertainty.

Computational intelligence synergies of fuzzy logic, neural networks and evolutionary computing

CERN Document Server

Siddique, Nazmul

2013-01-01

Computational Intelligence: Synergies of Fuzzy Logic, Neural Networks and Evolutionary Computing presents an introduction to some of the cutting edge technological paradigms under the umbrella of computational intelligence. Computational intelligence schemes are investigated with the development of a suitable framework for fuzzy logic, neural networks and evolutionary computing, neuro-fuzzy systems, evolutionary-fuzzy systems and evolutionary neural systems. Applications to linear and non-linear systems are discussed with examples. Key features: Covers all the aspect

Short- and long-lasting consequences of novelty, deviance and surprise on brain and cognition.

Science.gov (United States)

Schomaker, J; Meeter, M

2015-08-01

When one encounters a novel stimulus this sets off a cascade of brain responses, activating several neuromodulatory systems. As a consequence novelty has a wide range of effects on cognition; improving perception and action, increasing motivation, eliciting exploratory behavior, and promoting learning. Here, we review these benefits and how they may arise in the brain. We propose a framework that organizes novelty's effects on brain and cognition into three groups. First, novelty can transiently enhance perception. This effect is proposed to be mediated by novel stimuli activating the amygdala and enhancing early sensory processing. Second, novel stimuli can increase arousal, leading to short-lived effects on action in the first hundreds of milliseconds after presentation. We argue that these effects are related to deviance, rather than to novelty per se, and link them to activation of the locus-coeruleus norepinephrine system. Third, spatial novelty may trigger the dopaminergic mesolimbic system, promoting dopamine release in the hippocampus, having longer-lasting effects, up to tens of minutes, on motivation, reward processing, and learning and memory. Copyright © 2015 Elsevier Ltd. All rights reserved.

Novelty Seeking and Drug Addiction in Humans and Animals: From Behavior to Molecules.

Science.gov (United States)

Wingo, Taylor; Nesil, Tanseli; Choi, Jung-Seok; Li, Ming D

2016-09-01

Global treatment of drug addiction costs society billions of dollars annually, but current psychopharmacological therapies have not been successful at desired rates. The increasing number of individuals suffering from substance abuse has turned attention to what makes some people more vulnerable to drug addiction than others. One personality trait that stands out as a contributing factor is novelty seeking. Novelty seeking, affected by both genetic and environmental factors, is defined as the tendency to desire novel stimuli and environments. It can be measured in humans through questionnaires and in rodents using behavioral tasks. On the behavioral level, both human and rodent studies demonstrate that high novelty seeking can predict the initiation of drug use and a transition to compulsive drug use and create a propensity to relapse. These predictions are valid for several drugs of abuse, such as alcohol, nicotine, cocaine, amphetamine, and opiates. On the molecular level, both novelty seeking and addiction are modulated by the central reward system in the brain. Dopamine is the primary neurotransmitter involved in the overlapping neural substrates of both parameters. In sum, the novelty-seeking trait can be valuable for predicting individual vulnerability to drug addiction and for generating successful treatment for patients with substance abuse disorders.

The role of oxytocin in familiarization-habituation responses to social novelty

Directory of Open Access Journals (Sweden)

Mattie eTops

2013-10-01

Full Text Available Stress or arousal responses to novel social contexts ease off when individuals get familiar with the social context. In the present study we investigated whether oxytocin is involved in this process of familiarization-habituation, as oxytocin is known to increase trust and decrease anxiety. Fifty-nine healthy female subjects took part in the same experimental procedure in two sessions separated by four weeks. In the first (novelty session state trust scores were significantly positively correlated with salivary oxytocin levels, while in the second (familiarity session state trust scores were significantly negatively correlated with salivary oxytocin levels. In a path model, oxytocin was associated with increased trust in the novelty session and trust was associated with decreased oxytocin levels in the familiarity session. The results are consistent with the idea that oxytocin decreases stress-to-novelty responses by promoting familiarization to novel social contexts.

Attentive novelty detection in humans is governed by pre-attentive sensory memory.

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Tiitinen, H; May, P; Reinikainen, K; Näätänen, R

1994-11-03

Being able to detect unusual, possibly dangerous events in the environment is a fundamental ability that helps ensure the survival of biological organisms. Novelty detection requires a memory system that models (builds neural representations of) events in the environment, so that changes are detected because they violate the predictions of the model. The earliest physiologically measurable brain response to novel auditory stimuli is the mismatch negativity, MMN, a component of the event-related potential. It is elicited when a predictable series of unvarying stimuli is unexpectedly followed by a deviating stimulus. As the occurrence of MMN is not usually affected by the direction of attention, MMN reflects the operation of automatic sensory (echoic) memory, the earliest memory system that builds traces of the acoustic environment against which new stimuli can be compared. The dependence of attentive novelty detection on earlier, pre-attentive processes, however, has remained elusive. Previous, related studies seem to suggest a relationship between MMN and attentive processes, although no conclusive evidence has so far been shown. Here we address novelty detection in humans both on a physiological and behavioural level, and show how attentive novelty detection is governed by a pre-attentive sensory memory mechanism.

40 CFR 405.80 - Applicability; description of the ice cream, frozen desserts, novelties and other dairy desserts...

Science.gov (United States)

2010-07-01

... cream, frozen desserts, novelties and other dairy desserts subcategory. 405.80 Section 405.80 Protection... PRODUCTS PROCESSING POINT SOURCE CATEGORY Ice Cream, Frozen Desserts, Novelties and Other Dairy Desserts Subcategory § 405.80 Applicability; description of the ice cream, frozen desserts, novelties and other dairy...

Research traditions and evolutionary explanations in medicine.

Science.gov (United States)

Méthot, Pierre-Olivier

2011-02-01

In this article, I argue that distinguishing 'evolutionary' from 'Darwinian' medicine will help us assess the variety of roles that evolutionary explanations can play in a number of medical contexts. Because the boundaries of evolutionary and Darwinian medicine overlap to some extent, however, they are best described as distinct 'research traditions' rather than as competing paradigms. But while evolutionary medicine does not stand out as a new scientific field of its own, Darwinian medicine is united by a number of distinctive theoretical and methodological claims. For example, evolutionary medicine and Darwinian medicine can be distinguished with respect to the styles of evolutionary explanations they employ. While the former primarily involves 'forward looking' explanations, the latter depends mostly on 'backward looking' explanations. A forward looking explanation tries to predict the effects of ongoing evolutionary processes on human health and disease in contemporary environments (e.g., hospitals). In contrast, a backward looking explanation typically applies evolutionary principles from the vantage point of humans' distant biological past in order to assess present states of health and disease. Both approaches, however, are concerned with the prevention and control of human diseases. In conclusion, I raise some concerns about the claim that 'nothing in medicine makes sense except in the light of evolution'.

Chaos Enhanced Differential Evolution in the Task of Evolutionary Control of Discrete Chaotic LOZI Map

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Roman Senkerik

2016-01-01

Full Text Available In this paper, evolutionary technique Differential Evolution (DE is used for the evolutionary tuning of controller parameters for the stabilization of selected discrete chaotic system, which is the two-dimensional Lozi map. The novelty of the approach is that the selected controlled discrete dissipative chaotic system is used within Chaos enhanced heuristic concept as the chaotic pseudo-random number generator to drive the mutation and crossover process in the DE. The idea was to utilize the hidden chaotic dynamics in pseudo-random sequences given by chaotic map to help Differential evolution algorithm in searching for the best controller settings for the same chaotic system. The optimizations were performed for three different required final behavior of the chaotic system, and two types of developed cost function. To confirm the robustness of presented approach, comparisons with canonical DE strategy and PSO algorithm have been performed.

Evolutionary foundations for cancer biology.

Science.gov (United States)

Aktipis, C Athena; Nesse, Randolph M

2013-01-01

New applications of evolutionary biology are transforming our understanding of cancer. The articles in this special issue provide many specific examples, such as microorganisms inducing cancers, the significance of within-tumor heterogeneity, and the possibility that lower dose chemotherapy may sometimes promote longer survival. Underlying these specific advances is a large-scale transformation, as cancer research incorporates evolutionary methods into its toolkit, and asks new evolutionary questions about why we are vulnerable to cancer. Evolution explains why cancer exists at all, how neoplasms grow, why cancer is remarkably rare, and why it occurs despite powerful cancer suppression mechanisms. Cancer exists because of somatic selection; mutations in somatic cells result in some dividing faster than others, in some cases generating neoplasms. Neoplasms grow, or do not, in complex cellular ecosystems. Cancer is relatively rare because of natural selection; our genomes were derived disproportionally from individuals with effective mechanisms for suppressing cancer. Cancer occurs nonetheless for the same six evolutionary reasons that explain why we remain vulnerable to other diseases. These four principles-cancers evolve by somatic selection, neoplasms grow in complex ecosystems, natural selection has shaped powerful cancer defenses, and the limitations of those defenses have evolutionary explanations-provide a foundation for understanding, preventing, and treating cancer.

Developmental and Evolutionary Perspectives on the Origin and Diversification of Arthropod Appendages.

Science.gov (United States)

Jockusch, Elizabeth L

2017-09-01

Jointed, segmented appendages are a key innovation of arthropods. The subsequent diversification of these appendages, both along the body axis and across taxa, has contributed to the evolutionary success of arthropods. Both developmental and fossil data are informative for understanding how these transitions occurred. Comparative analyses help to pinpoint the developmental novelties that distinguish arthropod appendages from the lobopodous appendages of other panarthropods, and that distinguish different appendage types. The fossil record of stem group arthropods is diverse and preserves intermediate steps in these evolutionary transitions, including some that cannot be directly inferred based on extant taxa. These lead to hypotheses that can be tested with comparative developmental data, as well as to reinterpretations of developmental results. One developmental novelty of arthropods is the reiterated deployment of the joint formation network, which divides the appendages into segments. The fossil record raises questions about how this joint formation network was first deployed, given the contrasting morphologies of appendages in stem group versus extant arthropods. The fossil record supports a character tree for appendage diversification showing progressive individuation of appendages in an anterior-to-posterior sequence. However, to date, developmental evidence provides at best limited support for this character tree. Recent interpretations of the fossil record suggest that the labrum of extant arthropods is a greatly reduced protocerebral appendage pair; this hypothesis is consistent with the extensive shared developmental patterning of the labrum and jointed appendages. Reciprocal illumination from fossils and developmental patterning in a phylogenetic context both makes sense of some results and helps motivates questions for future research. © The Author 2017. Published by Oxford University Press on behalf of the Society for Integrative and Comparative

Testing evolutionary hypotheses for phenotypic divergence using landscape genetics.

Science.gov (United States)

Funk, W Chris; Murphy, Melanie A

2010-02-01

Understanding the evolutionary causes of phenotypic variation among populations has long been a central theme in evolutionary biology. Several factors can influence phenotypic divergence, including geographic isolation, genetic drift, divergent natural or sexual selection, and phenotypic plasticity. But the relative importance of these factors in generating phenotypic divergence in nature is still a tantalizing and unresolved problem in evolutionary biology. The origin and maintenance of phenotypic divergence is also at the root of many ongoing debates in evolutionary biology, such as the extent to which gene flow constrains adaptive divergence (Garant et al. 2007) and the relative importance of genetic drift, natural selection, and sexual selection in initiating reproductive isolation and speciation (Coyne & Orr 2004). In this issue, Wang & Summers (2010) test the causes of one of the most fantastic examples of phenotypic divergence in nature: colour pattern divergence among populations of the strawberry poison frog (Dendrobates pumilio) in Panama and Costa Rica (Fig. 1). This study provides a beautiful example of the use of the emerging field of landscape genetics to differentiate among hypotheses for phenotypic divergence. Using landscape genetic analyses, Wang & Summers were able to reject the hypotheses that colour pattern divergence is due to isolation-by-distance (IBD) or landscape resistance. Instead, the hypothesis left standing is that colour divergence is due to divergent selection, in turn driving reproductive isolation among populations with different colour morphs. More generally, this study provides a wonderful example of how the emerging field of landscape genetics, which has primarily been applied to questions in conservation and ecology, now plays an essential role in evolutionary research.

Symbionticism revisited: a discussion of the evolutionary impact of intracellular symbioses.

Science.gov (United States)

Taylor, F J

1979-04-11

Wallin (1927) first published the notion that the fusion of bacteria with host cells was the principal source of genetic novelty for speciation. He suggested that mitochondria are transitional elements in this process. While the significance that he attributed to symbiosis now seem excessive, he was one of the first authors to be aware of the evolutionary potential of symbiotic events and his view of mitochondria may not seem strange to many cell biologist today. The most significant evolutionary development which has been attributed to intracellular symbiosis is the origin of eukaryotic cellular organization. The current status of the 'serial endosymbiosis hypothesis' is briefly review. The case for the symbiotic origin of the chloroplast, based principally on 16 S RNA oligonucleotide cataloguing, is very strong. Mitochondrial origins are more obscure but also appear to be symbiotic due to recent 18 S cataloguing from wheat embryos. The probablility of the multiple origin of some eukaryotic organelles is also examined, the processes in question being the acquisition of distinct stocks of chloroplasts from disparate photosynthetic prokaryotes and the secondary donation of organelles from degenerate eukaryotic endosymbionts to their hosts, with specific reference to the dinoflagellates Peridinium balticum, Kryptoperidinium foliaceum and the ciliate Mesodinium rubrum. It is concluded that the evolutionary potential of intracellular symbiosis ('cytobiosis': a term introduced in this paper) is great, with the best established influence being on the origin of eukaryotic chloroplasts. Together with the potential effects of viral vectors, symbiosis serves as a supplementary speciation mechanism capable of producing directed evolutionary changes. It is likely that these processes will explain some of the apparent anomalies in evolutionary rates and direction which are not readily explicable by the conventional synthetic theory of evolution.

Novelties on Sharepoint Collaboration Workspace

CERN Multimedia

HR Department

2012-01-01

Your Sharepoint Collaboration workspaces will have to migrate to the new Sharepoint 2010 version. As soon as you will create a new site or subsite within your own site or as soon as you will click on “Update my site”, you will be forced to migrate to Sharepoint 2010. In order to anticipate these changes, the technical training invites you to discover all the new features of this interface in a new one day course called “Novelties on Sharepoint Collaboration Workspace 2010”. To sign in, please click on our training catalogue.

Autonomous visual exploration creates developmental change in familiarity and novelty seeking behaviors

Directory of Open Access Journals (Sweden)

Sammy ePerone

2013-09-01

Full Text Available What motivates children to radically transform themselves during early development? We addressed this question in the domain of infant visual exploration. Over the first year, infants’ exploration shifts from familiarity to novelty seeking. This shift is delayed in preterm relative to term infants and is stable within individuals over the course of the first year. Laboratory tasks have shed light on the nature of this familiarity-to-novelty shift, but it is not clear what motivates the infant to change her exploratory style. We probed this by letting a Dynamic Neural Field (DNF model of visual exploration develop itself via accumulating experience in a virtual world. We then situated it in a canonical laboratory task. Much like infants, the model exhibited a familiarity-to-novelty shift. When we manipulated the initial conditions of the model, the model’s performance was developmentally delayed much like preterm infants. This delay was overcome by enhancing the model’s experience during development. We also found that the model’s performance was stable at the level of the individual. Our simulations indicate that novelty seeking emerges with no explicit motivational source via the accumulation of visual experience within a complex, dynamical exploratory system.

Literary study and evolutionary theory : A review essay.

Science.gov (United States)

Carroll, J

1998-09-01

Several recent books have claimed to integrate literary study with evolutionary biology. All of the books here considered, except Robert Storey's, adopt conceptions of evolutionary theory that are in some way marginal to the Darwinian adaptationist program. All the works attempt to connect evolutionary study with various other disciplines or methodologies: for example, with cultural anthropology, cognitive psychology, the psychology of emotion, neurobiology, chaos theory, or structuralist linguistics. No empirical paradigm has yet been established for this field, but important steps have been taken, especially by Storey, in formulating basic principles, identifying appropriate disciplinary connections, and marking out lines of inquiry. Reciprocal efforts are needed from biologists and social scientists.

Making sense of infant familiarity and novelty responses to words at lexical onset

Directory of Open Access Journals (Sweden)

Rory A DePaolis

2016-05-01

Full Text Available This study suggests that familiarity and novelty preferences in infant experimental tasks can in some instances be interpreted together as a single indicator of language advance. We provide evidence to support this idea based on our use of the auditory headturn preference paradigm to record responses to words likely to be either familiar or unfamiliar to infants. Fifty-nine ten-month-old infants were tested. The task elicited mixed preferences: familiarity (longer average looks to the words likely to be familiar to the infants, novelty (longer average looks to the words likely to be unfamiliar and no-preference (similar-length of looks to both type of words. The infants who exhibited either a familiarity or a novelty response were more advanced on independent indices of phonetic advance than the infants who showed no preference. In addition, infants exhibiting novelty responses were more lexically advanced than either the infants who exhibited familiarity or those who showed no-preference. The results provide partial support for Hunter and Ames’ (1988 developmental model of attention in infancy and suggest caution when interpreting studies indexed to chronological age.

Toward behavioural innovation economics – Heuristics and biases in choice under novelty

OpenAIRE

Kate Morrison; Jason Potts

2008-01-01

A framework for ‘behavioural innovation economics’ is proposed here as a synthesis of behavioural economics and innovation economics in the specific context of choice under novelty. We seek to apply the heuristics and biases framework of behavioural economics to the study of the innovation process in order to map and analyze systematic choice failures in the innovation process. We elaborate the distinction between choice under uncertainty and choice under novelty, as well as drawing out the ‘...

Vulnerability of classifiers to evolutionary generated adversarial examples

Czech Academy of Sciences Publication Activity Database

Vidnerová, Petra; Neruda, Roman

submitted 14.1. 2017 (2018) ISSN 0941-0643 R&D Projects: GA ČR GA15-18108S Institutional support: RVO:67985807 Keywords : supervised learning * neural networks * kernel methods * genetic algorithm s * adversarial examples Subject RIV: IN - Informatics, Computer Science Impact factor: 2.505, year: 2016

User-producer Interaction and the Degree of Novelty of Innovations

DEFF Research Database (Denmark)

Harirchi, Gouya; Chaminade, Cristina

User-producer interactions have been traditionally recognized as important for innovation. With the rapid growth of emerging economies’ markets, and an increasing degree of technological sophistication of both users and producers in those markets, user-producer interaction is becoming global....... The existing literature is quite limited in explaining how collaboration with users in different income regions affects the degree of innovations’ novelty. Using original firm-level data collected in nine countries, this paper argues that collaborating with international customers is positively related...... to higher degrees of novelty. Furthermore, firms in low- and middle-income countries will benefit more from south-south collaboration than a south-north one, at least in terms of collaboration with customers for innovation....

The neural basis of novelty and appropriateness in processing of creative chunk decomposition.

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Huang, Furong; Fan, Jin; Luo, Jing

2015-06-01

Novelty and appropriateness have been recognized as the fundamental features of creative thinking. However, the brain mechanisms underlying these features remain largely unknown. In this study, we used event-related functional magnetic resonance imaging (fMRI) to dissociate these mechanisms in a revised creative chunk decomposition task in which participants were required to perform different types of chunk decomposition that systematically varied in novelty and appropriateness. We found that novelty processing involved functional areas for procedural memory (caudate), mental rewarding (substantia nigra, SN), and visual-spatial processing, whereas appropriateness processing was mediated by areas for declarative memory (hippocampus), emotional arousal (amygdala), and orthography recognition. These results indicate that non-declarative and declarative memory systems may jointly contribute to the two fundamental features of creative thinking. Copyright © 2015 Elsevier Inc. All rights reserved.

Cultural Novelty and Adjustment: Western Business Expatriates in China

DEFF Research Database (Denmark)

Selmer, Jan

2006-01-01

Western business expatriates in China. Three sociocultural adjustment variables were examined; general, interaction and work adjustment. Although a negative relationship was hypothesized between cultural novelty and the three adjustment variables, results of the hierarchical multiple regression analysis...

Relationship between ethanol preference and sensation/novelty seeking.

Science.gov (United States)

Manzo, Lidia; Gómez, Ma José; Callejas-Aguilera, José E; Donaire, Rocío; Sabariego, Marta; Fernández-Teruel, Alberto; Cañete, Antoni; Blázquez, Gloria; Papini, Mauricio R; Torres, Carmen

2014-06-22

High- and low-avoidance Roman inbred rat strains (RHA-I, RLA-I) were selected for extreme differences in two-way active avoidance. RHA-I rats also express less anxiety than RLA-I rats. This study compared male Roman rats in ethanol preference and sensation/novelty seeking. Rats were first exposed in counterbalanced order to the hole-board test (forced exposure to novelty) and the Y-maze and emergence tests (free choice between novel and familiar locations). Then, rats were tested in 24-h, two-bottle preference tests with water in one bottle and ethanol (2, 4, 6, 8, or 10% in successive days). Compared to RLA-I rats, RHA-I rats showed (1) higher frequency and time in head dipping, (2) higher activity, and (3) lower frequency of rearing and grooming in the hole-board test, and (4) remained in the novel arm longer in the Y-maze test. No strain differences were observed in the emergence test. RHA-I rats exhibited higher preference for and consumed more ethanol than RLA-I rats at all concentrations. However, both strains preferred ethanol over water for 2-4% concentrations, but water over ethanol for 6-10% concentrations. Factorial analysis with all the rats pooled identified a two-factor solution, one grouping preferred ethanol concentrations (2-4%) with head dipping and grooming in the hole board, and another factor grouping the nonpreferred ethanol concentrations (6-10%) with activity in the hole board and novel-arm time in the Y-maze test. These results show that preference for ethanol is associated with different aspects of behavior measured in sensation/novelty-seeking tests. Copyright © 2014 Elsevier Inc. All rights reserved.

Deep Recurrent Neural Network-Based Autoencoders for Acoustic Novelty Detection

Directory of Open Access Journals (Sweden)

Erik Marchi

2017-01-01

Full Text Available In the emerging field of acoustic novelty detection, most research efforts are devoted to probabilistic approaches such as mixture models or state-space models. Only recent studies introduced (pseudo-generative models for acoustic novelty detection with recurrent neural networks in the form of an autoencoder. In these approaches, auditory spectral features of the next short term frame are predicted from the previous frames by means of Long-Short Term Memory recurrent denoising autoencoders. The reconstruction error between the input and the output of the autoencoder is used as activation signal to detect novel events. There is no evidence of studies focused on comparing previous efforts to automatically recognize novel events from audio signals and giving a broad and in depth evaluation of recurrent neural network-based autoencoders. The present contribution aims to consistently evaluate our recent novel approaches to fill this white spot in the literature and provide insight by extensive evaluations carried out on three databases: A3Novelty, PASCAL CHiME, and PROMETHEUS. Besides providing an extensive analysis of novel and state-of-the-art methods, the article shows how RNN-based autoencoders outperform statistical approaches up to an absolute improvement of 16.4% average F-measure over the three databases.

Deep Recurrent Neural Network-Based Autoencoders for Acoustic Novelty Detection.

Science.gov (United States)

Marchi, Erik; Vesperini, Fabio; Squartini, Stefano; Schuller, Björn

2017-01-01

In the emerging field of acoustic novelty detection, most research efforts are devoted to probabilistic approaches such as mixture models or state-space models. Only recent studies introduced (pseudo-)generative models for acoustic novelty detection with recurrent neural networks in the form of an autoencoder. In these approaches, auditory spectral features of the next short term frame are predicted from the previous frames by means of Long-Short Term Memory recurrent denoising autoencoders. The reconstruction error between the input and the output of the autoencoder is used as activation signal to detect novel events. There is no evidence of studies focused on comparing previous efforts to automatically recognize novel events from audio signals and giving a broad and in depth evaluation of recurrent neural network-based autoencoders. The present contribution aims to consistently evaluate our recent novel approaches to fill this white spot in the literature and provide insight by extensive evaluations carried out on three databases: A3Novelty, PASCAL CHiME, and PROMETHEUS. Besides providing an extensive analysis of novel and state-of-the-art methods, the article shows how RNN-based autoencoders outperform statistical approaches up to an absolute improvement of 16.4% average F -measure over the three databases.

Novelty exposure overcomes foot shock-induced spatial-memory impairment by processes of synaptic-tagging in rats.

Science.gov (United States)

Almaguer-Melian, William; Bergado-Rosado, Jorge; Pavón-Fuentes, Nancy; Alberti-Amador, Esteban; Mercerón-Martínez, Daymara; Frey, Julietta U

2012-01-17

Novelty processing can transform short-term into long-term memory. We propose that this memory-reinforcing effect of novelty could be explained by mechanisms outlined in the "synaptic tagging hypothesis." Initial short-term memory is sustained by a transient plasticity change at activated synapses and sets synaptic tags. These tags are later able to capture and process the plasticity-related proteins (PRPs), which are required to transform a short-term synaptic change into a long-term one. Novelty is involved in inducing the synthesis of PRPs [Moncada D, et al. (2011) Proc Natl Acad Sci USA 108:12937-12936], which are then captured by the tagged synapses, consolidating memory. In contrast to novelty, stress can impair learning, memory, and synaptic plasticity. Here, we address questions as to whether novelty-induced PRPs are able to prevent the loss of memory caused by stress and if the latter would not interact with the tag-setting process. We used water-maze (WM) training as a spatial learning paradigm to test our hypothesis. Stress was induced by a strong foot shock (FS; 5 × 1 mA, 2 s) applied 5 min after WM training. Our data show that FS reduced long-term but not short-term memory in the WM paradigm. This negative effect on memory consolidation was time- and training-dependent. Interestingly, novelty exposure prevented the stress-induced memory loss of the spatial task and increased BDNF and Arc expression. This rescuing effect was blocked by anisomycin, suggesting that WM-tagged synapses were not reset by FS and were thus able to capture the novelty-induced PRPs, re-establishing FS-impaired long-term memory.

D4 receptor deficiency in mice has limited effects on impulsivity and novelty seeking.

Science.gov (United States)

Helms, C M; Gubner, N R; Wilhelm, C J; Mitchell, S H; Grandy, D K

2008-09-01

Alleles of the human dopamine D(4) receptor (D(4)R) gene (DRD4.7) have repeatedly been found to correlate with novelty seeking, substance abuse, pathological gambling, and attention-deficit hyperactivity disorder (ADHD). If these various psychopathologies are a result of attenuated D(4)R-mediated signaling, mice lacking D(4)Rs (D(4)KO) should be more impulsive than wild-type (WT) mice and exhibit more novelty seeking. However, in our study, D(4)KO and WT mice showed similar levels of impulsivity as measured by delay discounting performance and response inhibition on a Go/No-go test, suggesting that D(4)R-mediated signaling may not affect impulsivity. D(4)KO mice were more active than WT mice in the first 5 min of a novel open field test, suggesting greater novelty seeking. For both genotypes, more impulsive mice habituated less in the novel open field. These data suggest that the absence of D(4)Rs is not sufficient to cause psychopathologies associated with heightened impulsivity and novelty seeking.

Consistency of Children's Inconsistent Preferences Attributable to Novelty

Science.gov (United States)

Bradbury, Hinton

1975-01-01

The analysis of logical and antilogical influences on preference made by Bradbury and Nelson is extended to a consideration of choices by children in kindergarten, Grade 4, and Grade 8. Conclusions are drawn concerning the dependence of intransitive preference on the collative variable of novelty in choice context. (Author/SDH)

Evolutionary developmental perspective for the origin of turtles: the folding theory for the shell based on the developmental nature of the carapacial ridge.

Science.gov (United States)

Kuratani, Shigeru; Kuraku, Shigehiro; Nagashima, Hiroshi

2011-01-01

The body plan of the turtle represents an example of evolutionary novelty for acquisition of the shell. Unlike similar armors in other vertebrate groups, the turtle shell involves the developmental repatterning of the axial skeleton and exhibits an unusual topography of musculoskeletal elements. Thus, the turtle provides an ideal case study for understanding changes in the developmental program associated with the morphological evolution of vertebrates. In this article, the evolution of the turtle-specific body plan is reviewed and discussed. The key to understanding shell patterning lies in the modification of the ribs, for which the carapacial ridge (CR), a turtle-specific embryonic anlage, is assumed to be responsible. The growth of the ribs is arrested in the axial part of the body, allowing dorsal and lateral oriented growth to encapsulate the scapula. Although the CR does not appear to induce this axial arrest per se, it has been shown to support the fan-shaped patterning of the ribs, which occurs concomitant with marginal growth of the carapace along the line of the turtle-specific folding that takes place in the lateral body wall. During the process of the folding, some trunk muscles maintain their ancestral connectivities, whereas the limb muscles establish new attachments specific to the turtle. The turtle body plan can thus be explained with our knowledge of vertebrate anatomy and developmental biology, consistent with the evolutionary origin of the turtle suggested by the recently discovered fossil species, Odontochelys. © 2011 Wiley Periodicals, Inc.

ADAPTIVE SELECTION OF AUXILIARY OBJECTIVES IN MULTIOBJECTIVE EVOLUTIONARY ALGORITHMS

Directory of Open Access Journals (Sweden)

I. A. Petrova

2016-05-01

Full Text Available Subject of Research.We propose to modify the EA+RL method, which increases efficiency of evolutionary algorithms by means of auxiliary objectives. The proposed modification is compared to the existing objective selection methods on the example of travelling salesman problem. Method. In the EA+RL method a reinforcement learning algorithm is used to select an objective – the target objective or one of the auxiliary objectives – at each iteration of the single-objective evolutionary algorithm.The proposed modification of the EA+RL method adopts this approach for the usage with a multiobjective evolutionary algorithm. As opposed to theEA+RL method, in this modification one of the auxiliary objectives is selected by reinforcement learning and optimized together with the target objective at each step of the multiobjective evolutionary algorithm. Main Results.The proposed modification of the EA+RL method was compared to the existing objective selection methods on the example of travelling salesman problem. In the EA+RL method and its proposed modification reinforcement learning algorithms for stationary and non-stationary environment were used. The proposed modification of the EA+RL method applied with reinforcement learning for non-stationary environment outperformed the considered objective selection algorithms on the most problem instances. Practical Significance. The proposed approach increases efficiency of evolutionary algorithms, which may be used for solving discrete NP-hard optimization problems. They are, in particular, combinatorial path search problems and scheduling problems.

Vibration-Based Adaptive Novelty Detection Method for Monitoring Faults in a Kinematic Chain

Directory of Open Access Journals (Sweden)

Jesus Adolfo Cariño-Corrales

2016-01-01

Full Text Available This paper presents an adaptive novelty detection methodology applied to a kinematic chain for the monitoring of faults. The proposed approach has the premise that only information of the healthy operation of the machine is initially available and fault scenarios will eventually develop. This approach aims to cover some of the challenges presented when condition monitoring is applied under a continuous learning framework. The structure of the method is divided into two recursive stages: first, an offline stage for initialization and retraining of the feature reduction and novelty detection modules and, second, an online monitoring stage to continuously assess the condition of the machine. Contrary to classical static feature reduction approaches, the proposed method reformulates the features by employing first a Laplacian Score ranking and then the Fisher Score ranking for retraining. The proposed methodology is validated experimentally by monitoring the vibration measurements of a kinematic chain driven by an induction motor. Two faults are induced in the motor to validate the method performance to detect anomalies and adapt the feature reduction and novelty detection modules to the new information. The obtained results show the advantages of employing an adaptive approach for novelty detection and feature reduction making the proposed method suitable for industrial machinery diagnosis applications.

Body plan of turtles: an anatomical, developmental and evolutionary perspective.

Science.gov (United States)

Nagashima, Hiroshi; Kuraku, Shigehiro; Uchida, Katsuhisa; Kawashima-Ohya, Yoshie; Narita, Yuichi; Kuratani, Shigeru

2012-03-01

The evolution of the turtle shell has long been one of the central debates in comparative anatomy. The turtle shell consists of dorsal and ventral parts: the carapace and plastron, respectively. The basic structure of the carapace comprises vertebrae and ribs. The pectoral girdle of turtles sits inside the carapace or the rib cage, in striking contrast to the body plan of other tetrapods. Due to this topological change in the arrangement of skeletal elements, the carapace has been regarded as an example of evolutionary novelty that violates the ancestral body plan of tetrapods. Comparing the spatial relationships of anatomical structures in the embryos of turtles and other amniotes, we have shown that the topology of the musculoskeletal system is largely conserved even in turtles. The positional changes seen in the ribs and pectoral girdle can be ascribed to turtle-specific folding of the lateral body wall in the late developmental stages. Whereas the ribs of other amniotes grow from the axial domain to the lateral body wall, turtle ribs remain arrested axially. Marginal growth of the axial domain in turtle embryos brings the morphologically short ribs in to cover the scapula dorsocaudally. This concentric growth appears to be induced by the margin of the carapace, which involves an ancestral gene expression cascade in a new location. These comparative developmental data allow us to hypothesize the gradual evolution of turtles, which is consistent with the recent finding of a transitional fossil animal, Odontochelys, which did not have the carapace but already possessed the plastron.

Memory effects of sleep, emotional valence, arousal and novelty in children.

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Vermeulen, Marije C M; van der Heijden, Kristiaan B; Benjamins, Jeroen S; Swaab, Hanna; van Someren, Eus J W

2017-06-01

Effectiveness of memory consolidation is determined by multiple factors, including sleep after learning, emotional valence, arousal and novelty. Few studies investigated how the effect of sleep compares with (and interacts with) these other factors, of which virtually none are in children. The present study did so by repeated assessment of declarative memory in 386 children (45% boys) aged 9-11 years through an online word-pair task. Children were randomly assigned to either a morning or evening learning session of 30 unrelated word-pairs with positive, neutral or negative valenced cues and neutral targets. After immediately assessing baseline recognition, delayed recognition was recorded either 12 or 24 h later, resulting in four different assessment schedules. One week later, the procedure was repeated with exactly the same word-pairs to evaluate whether effects differed for relearning versus original novel learning. Mixed-effect logistic regression models were used to evaluate how the probability of correct recognition was affected by sleep, valence, arousal, novelty and their interactions. Both immediate and delayed recognition were worse for pairs with negatively valenced or less arousing cue words. Relearning improved immediate and delayed word-pair recognition. In contrast to these effects, sleep did not affect recognition, nor did sleep moderate the effects of arousal, valence and novelty. The findings suggest a robust inclination of children to specifically forget the pairing of words to negatively valenced cue words. In agreement with a recent meta-analysis, children seem to depend less on sleep for the consolidation of information than has been reported for adults, irrespective of the emotional valence, arousal and novelty of word-pairs. © 2017 European Sleep Research Society.

Evolutionary computation in zoology and ecology.

Science.gov (United States)

Boone, Randall B

2017-12-01

Evolutionary computational methods have adopted attributes of natural selection and evolution to solve problems in computer science, engineering, and other fields. The method is growing in use in zoology and ecology. Evolutionary principles may be merged with an agent-based modeling perspective to have individual animals or other agents compete. Four main categories are discussed: genetic algorithms, evolutionary programming, genetic programming, and evolutionary strategies. In evolutionary computation, a population is represented in a way that allows for an objective function to be assessed that is relevant to the problem of interest. The poorest performing members are removed from the population, and remaining members reproduce and may be mutated. The fitness of the members is again assessed, and the cycle continues until a stopping condition is met. Case studies include optimizing: egg shape given different clutch sizes, mate selection, migration of wildebeest, birds, and elk, vulture foraging behavior, algal bloom prediction, and species richness given energy constraints. Other case studies simulate the evolution of species and a means to project shifts in species ranges in response to a changing climate that includes competition and phenotypic plasticity. This introduction concludes by citing other uses of evolutionary computation and a review of the flexibility of the methods. For example, representing species' niche spaces subject to selective pressure allows studies on cladistics, the taxon cycle, neutral versus niche paradigms, fundamental versus realized niches, community structure and order of colonization, invasiveness, and responses to a changing climate.

Shared Leadership Improves Team Novelty: The Mechanism and Its Boundary Condition

Science.gov (United States)

Sun, Xiaomin; Jie, Yuan; Wang, Yilu; Xue, Gang; Liu, Yan

2016-01-01

Previous research has revealed the significant impact of shared leadership on team creativity, yet the mechanism underlying this relationship has rarely been investigated. The current research examined how shared leadership influenced team creativity (novelty and usefulness) across 3 studies using both long-term project teams and temporal task teams in the laboratory. The results showed that shared leadership enhanced the novelty dimension of team creativity by improving constructive controversy. Furthermore, team goal orientation moderated this effect. The indirect effect of constructive controversy holds for teams with learning goal orientation but not for those with performance goal orientation. Such patterns were not found in the usefulness dimension of team creativity. PMID:28066289

Evolutionary adaptations: theoretical and practical implications for visual ergonomics.

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Fostervold, Knut Inge; Watten, Reidulf G; Volden, Frode

2014-01-01

The literature discussing visual ergonomics often mention that human vision is adapted to light emitted by the sun. However, theoretical and practical implications of this viewpoint is seldom discussed or taken into account. The paper discusses some of the main theoretical implications of an evolutionary approach to visual ergonomics. Based on interactional theory and ideas from ecological psychology an evolutionary stress model is proposed as a theoretical framework for future research in ergonomics and human factors. The model stresses the importance of developing work environments that fits with our evolutionary adaptations. In accordance with evolutionary psychology, the environment of evolutionary adaptedness (EEA) and evolutionarily-novel environments (EN) are used as key concepts. Using work with visual display units (VDU) as an example, the paper discusses how this knowledge can be utilized in an ergonomic analysis of risk factors in the work environment. The paper emphasises the importance of incorporating evolutionary theory in the field of ergonomics. Further, the paper encourages scientific practices that further our understanding of any phenomena beyond the borders of traditional proximal explanations.

Popularity and Novelty Dynamics in Evolving Networks.

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Abbas, Khushnood; Shang, Mingsheng; Abbasi, Alireza; Luo, Xin; Xu, Jian Jun; Zhang, Yu-Xia

2018-04-20

Network science plays a big role in the representation of real-world phenomena such as user-item bipartite networks presented in e-commerce or social media platforms. It provides researchers with tools and techniques to solve complex real-world problems. Identifying and predicting future popularity and importance of items in e-commerce or social media platform is a challenging task. Some items gain popularity repeatedly over time while some become popular and novel only once. This work aims to identify the key-factors: popularity and novelty. To do so, we consider two types of novelty predictions: items appearing in the popular ranking list for the first time; and items which were not in the popular list in the past time window, but might have been popular before the recent past time window. In order to identify the popular items, a careful consideration of macro-level analysis is needed. In this work we propose a model, which exploits item level information over a span of time to rank the importance of the item. We considered ageing or decay effect along with the recent link-gain of the items. We test our proposed model on four various real-world datasets using four information retrieval based metrics.

Evolutionary Biology: Its Value to Society

Science.gov (United States)

Carson, Hampton L.

1972-01-01

Cites examples of the contribution of basic research in evolutionary biology to the solution of problems facing society (1) by dispelling myths about human origins, the nature of the individual, and the nature of race (2) by providing basic data concerning the effects of overpopulation, the production of improved sources of food, resistance of…

A neurocomputational account of reward and novelty processing and effects of psychostimulants in attention deficit hyperactivity disorder.

Science.gov (United States)

Sethi, Arjun; Voon, Valerie; Critchley, Hugo D; Cercignani, Mara; Harrison, Neil A

2018-05-01

Computational models of reinforcement learning have helped dissect discrete components of reward-related function and characterize neurocognitive deficits in psychiatric illnesses. Stimulus novelty biases decision-making, even when unrelated to choice outcome, acting as if possessing intrinsic reward value to guide decisions toward uncertain options. Heightened novelty seeking is characteristic of attention deficit hyperactivity disorder, yet how this influences reward-related decision-making is computationally encoded, or is altered by stimulant medication, is currently uncertain. Here we used an established reinforcement-learning task to model effects of novelty on reward-related behaviour during functional MRI in 30 adults with attention deficit hyperactivity disorder and 30 age-, sex- and IQ-matched control subjects. Each participant was tested on two separate occasions, once ON and once OFF stimulant medication. OFF medication, patients with attention deficit hyperactivity disorder showed significantly impaired task performance (P = 0.027), and greater selection of novel options (P = 0.004). Moreover, persistence in selecting novel options predicted impaired task performance (P = 0.025). These behavioural deficits were accompanied by a significantly lower learning rate (P = 0.011) and heightened novelty signalling within the substantia nigra/ventral tegmental area (family-wise error corrected P attention deficit hyperactivity disorder participants' overall task performance (P = 0.011), increased reward-learning rates (P = 0.046) and enhanced their ability to differentiate optimal from non-optimal novel choices (P = 0.032). It also reduced substantia nigra/ventral tegmental area responses to novelty. Preliminary cross-sectional evidence additionally suggested an association between long-term stimulant treatment and a reduction in the rewarding value of novelty. These data suggest that aberrant substantia nigra/ventral tegmental area novelty processing plays an

Tree shrews (tupaia belangeri exhibit novelty preference in the novel location memory task with 24-hour retention periods.

Directory of Open Access Journals (Sweden)

Jayakrishnan H R Nair

2014-04-01

Full Text Available Novelty preference is pervasive in mammalian species, and describes an inherent tendency to preferentially explore novelty. The novel location memory task studied here assesses the ability of animals to form accurate memories of a spatial configuration, consisting of several identical objects placed within an arena. Tree shrews were first familiarized with a particular object configuration during several sessions, and then an object was displaced during a test session. Tree shrews exhibited enhanced exploration when confronted with this novel configuration. The most reliable indicator associated with novelty preference was an enhancement in directed exploration towards the novel object, although we also observed a non-specific overall increase in exploration in one experiment. During the test session, we also observed an exploration of the location, which had previously been occupied by the displaced object, an effect termed empty quadrant. Our behavioral findings suggest multiple stages of spatial memory formation in tree shrews that are associated with various forms of behavioral responses to novelty. Reduced novelty preference has been linked to major depressive disorder in human patients. Given the established social conflict depression model in tree shrews, we anticipate that the study of the neural circuits of novelty preference and their malfunction during depression may have implications for understanding or treating depression in humans.

The interaction between hippocampal GABA-B and cannabinoid receptors upon spatial change and object novelty discrimination memory function.

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Nasehi, Mohammad; Alaghmandan-Motlagh, Niyousha; Ebrahimi-Ghiri, Mohaddeseh; Nami, Mohammad; Zarrindast, Mohammad-Reza

2017-10-01

Previous studies have postulated functional links between GABA and cannabinoid systems in the hippocampus. The aim of the present study was to investigate any possible interaction between these systems in spatial change and object novelty discrimination memory consolidation in the dorsal hippocampus (CA1 region) of NMRI mice. Assessment of the spatial change and object novelty discrimination memory function was carried out in a non-associative task. The experiment comprised mice exposure to an open field containing five objects followed by the examination of their reactivity to object displacement (spatial change) and object substitution (object novelty) after three sessions of habituation. Our results showed that the post-training intraperitoneal administration of the higher dose of ACPA (0.02 mg/kg) impaired both spatial change and novelty discrimination memory functions. Meanwhile, the higher dose of GABA-B receptor agonist, baclofen, impaired the spatial change memory by itself. Moreover, the post-training intra-CA1 microinjection of a subthreshold dose of baclofen increased the ACPA effect on spatial change and novelty discrimination memory at a lower and higher dose, respectively. On the other hand, the lower and higher but not mid-level doses of GABA-B receptor antagonist, phaclofen, could reverse memory deficits induced by ACPA. However, phaclofen at its mid-level dose impaired the novelty discrimination memory and whereas the higher dose impaired the spatial change memory. Based on our findings, GABA-B receptors in the CA1 region appear to modulate the ACPA-induced cannabinoid CB1 signaling upon spatial change and novelty discrimination memory functions.

An Individual Psychology of Novelty-Seeking, Creativity and Innovation

NARCIS (Netherlands)

T.S. Schweizer (Sophie)

2004-01-01

textabstractENGLISH ABSTRACT: What does it take to generate something new? The desire to seek something new, the satisfaction of finding something, sharing these findings with others who also recognize them as new - these are key ingredients of generating a novelty. Part One of this book proposes a

Childhood inhibitory control and adolescent impulsivity and novelty seeking as differential predictors of relational and overt aggression.

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Sarkisian, Katherine; Van Hulle, Carol; Lemery-Chalfant, Kathryn; Goldsmith, H H

2017-04-01

Impulsivity is commonly conflated with novelty seeking, but these traits are conceptually independent and hold different predictive implications. Using a multi-informant, longitudinal design, we examined childhood inhibitory control, as well as adolescent impulsivity and novelty seeking, as predictors of aggression in a sample of 976 twins. Lower childhood inhibitory control and higher adolescent impulsivity predicted both overt and relational aggression in regression analyses that accounted for sex, puberty status, age, and socioeconomic status. As predicted, novelty seeking did not predict aggression, a finding that supports its independence from impulsivity.

Capacity of novelty-induced locomotor activity and the hole-board test to predict sensitivity to the conditioned rewarding effects of cocaine.

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Arenas, M Carmen; Daza-Losada, Manuel; Vidal-Infer, Antonio; Aguilar, Maria A; Miñarro, José; Rodríguez-Arias, Marta

2014-06-22

Novelty-seeking in rodents, defined as enhanced specific exploration of novel situations, is considered to predict the response of animals to drugs of abuse and, thus, allow "drug-vulnerable" individuals to be identified. The main objective of this study was to assess the predictive ability of two well-known paradigms of the novelty-seeking trait - novelty-induced locomotor activity (which distinguishes High- and Low-Responder mice, depending on their motor activity) and the hole-board test (which determines High- and Low-Novelty Seeker mice depending on the number of head dips they perform) - to identify subjects that would subsequently be more sensitive to the conditioned rewarding effects of cocaine in a population of young adult (PND 56) and adolescent (PND 35) OF1 mice of both sexes. Conditioned place preference (CPP), a useful tool for evaluating the sensitivity of individuals to the incentive properties of addictive drugs, was induced with a sub-threshold dose of cocaine (1 mg/kg, i.p.). Our results showed that novelty-induced motor activity had a greater predictive capacity to identify "vulnerable-drug" individuals among young-adult mice (PND 56), while the hole-board test was more effective in adolescents (PND 35). High-NR young-adults, which presented higher motor activity in the first ten minutes of the test (novelty-reactivity), were 3.9 times more likely to develop cocaine-induced CPP than Low-NR young-adults. When total activity (1h) was evaluated (novelty-habituation), only High-R (novelty-non-habituating) young-adult male and Low-R (novelty-habituating) female mice produced a high conditioning score. However, only High-Novelty Seeker male and female adolescents and Low-Novelty Seeker female young-adult animals (according to the hole-board test), acquired cocaine-induced CPP. These findings should contribute to the development of screening methods for identifying at-risk human drug users and prevention strategies for those with specific

Polycose Taste Pre-Exposure Fails to Influence Behavioral and Neural Indices of Taste Novelty

OpenAIRE

Barot, Sabiha K.; Bernstein, Ilene L.

2005-01-01

Taste novelty can strongly modulate the speed and efficacy of taste aversion learning. Novel sweet tastes enhance c-Fos-like immunoreactivity (FLI) in the central amygdala and insular cortex. The present studies examined whether this neural correlate of novelty extends to different taste types by measuring FLI signals after exposure to novel and familiar polysaccharide (Polycose®) and salt (NaCl) tastes. Novel Polycose not only failed to elevate FLI expression in central amygdala and insular ...

Effect of fractionated extracts and isolated pure compounds of Spondias mombin (L. Anacardiaceae) leaves on novelty-induced rearing and grooming behaviours in mice.

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Ayoka, Abiodun O; Owolabi, Rotimi A; Bamitale, Samuel K; Akomolafe, Rufus O; Aladesanmi, Joseph A; Ukponmwan, Eghe O

2013-01-01

This study attempted to elucidate the neurotransmitter systems involved in the neurophysiological properties of ethanolic extract, fractions and pure isolates of Spondias mombin leaves in mice (n = 6) after intraperitoneal (i.p.) route of administration.The crude ethanolic extract of Spondian mombin leaves was fractionated using the partitioning method to obtain the ethylacetate, butanolic and aqueous fractions. Open column chromatographic fractionation of the ethylacetate fraction yielded seven sub-fractions, out of which the pure coumaroyl, quercetin and gallic acid derivatives were obtained after purification on Sephadex LH 20. The ethanolic extract, butanolic fraction, ethylacetate subfractions and pure isolates of the Spondian mombin leaves were tested on novelty-induced rearing and grooming behaviours in mice with standard pharmacological tools using the open field method. The extract and its fractions decreased novelty-induced rearing in a dose-dependent manner. While the Coumaroyl derivative had no effect on novelty-induced rearing, it significantly reversed the inhibitory effect of yohimbine, propranolol and haloperidol on novelty-induced rearing. Quercetin significantly potentiated the inhibitory effect of yohimbine on novelty-induced rearing. Naloxone significantly potentiated the quercetin-induced suppression of novelty-induced rearing. Gallic acid derivative significantly potentiated the inhibitory effect of yohimbine on novelty-induced rearing. Naloxone, atropine and haloperidol pretreatments significantly potentiated gallic acid derivative-induced suppression of novelty-induced rearing.The extract and its fractions had biphasic effect on novelty-induced grooming in mice. Coumaroyl derivative significantly increased novelty-induced grooming, while quercetin and gallic acid derivative decreased novelty-induced grooming significantly. The three pure isolates significantly reversed the effects of yohimbine and atropine on the novelty-induced grooming in

Biological causal links on physiological and evolutionary time scales.

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Karmon, Amit; Pilpel, Yitzhak

2016-04-26

Correlation does not imply causation. If two variables, say A and B, are correlated, it could be because A causes B, or that B causes A, or because a third factor affects them both. We suggest that in many cases in biology, the causal link might be bi-directional: A causes B through a fast-acting physiological process, while B causes A through a slowly accumulating evolutionary process. Furthermore, many trained biologists tend to consistently focus at first on the fast-acting direction, and overlook the slower process in the opposite direction. We analyse several examples from modern biology that demonstrate this bias (codon usage optimality and gene expression, gene duplication and genetic dispensability, stem cell division and cancer risk, and the microbiome and host metabolism) and also discuss an example from linguistics. These examples demonstrate mutual effects between the fast physiological processes and the slow evolutionary ones. We believe that building awareness of inference biases among biologists who tend to prefer one causal direction over another could improve scientific reasoning.

Effect of Age and Food Novelty on Food Memory

NARCIS (Netherlands)

Sulmont-Rosse, C.; Moller, P.; Issanchou, S.; Köster, E.P.

2008-01-01

The influence of age of the consumer and food novelty on incidentally learned food memory was investigated by providing a meal containing novel and familiar target items under the pretense of a study on hunger feelings to 34 young and 36 older participants in France and to 24 young and 20 older

Testing evolutionary convergence on Europa

Energy Technology Data Exchange (ETDEWEB)

Chela-Flores, Julian [Instituto de Estudios Avanzados, Caracas (Venezuela); [Abdus Salam International Centre for Theoretical Physics, Trieste (Italy)

2002-11-01

A major objective in solar system exploration is the insertion of appropriate biology-oriented experiments in future missions. We discuss various reasons for suggesting that this type of research be considered a high priority for feasibility studies and, subsequently, for technological development of appropriate melters and submersibles. Based on numerous examples, we argue in favour of the assumption that Darwin's theory is valid for the evolution of life anywhere in the universe. We have suggested how to obtain preliminary insights into the question of the distribution of life in the universe. Universal evolution of intelligent behaviour is at the end of an evolutionary pathway, in which evolution of ion channels in the membrane of microorganisms occurs in its early stages. Further, we have argued that a preliminary test of this conjecture is feasible with experiments on the Europan surface or ocean, involving evolutionary biosignatures (ion channels). This aspect of the exploration for life in the solar system should be viewed as a complement to the astronomical approach for the search of evidence of the later stages of the evolutionary pathways towards intelligent behaviour. (author)

Evolutionary computing in Nuclear Engineering Institute/CNEN-Brazil

International Nuclear Information System (INIS)

Pereira, Claudio M.N.A.; Lapa, Celso M.F.; Lapa, Nelbia da Silva; Mol, Antonio C.

2000-01-01

This paper aims to discuss the importance of evolutionary computation (CE) for nuclear engineering and the development of this area in the Instituto de Engenharia Nuclear (IEN) at the last years. Are describe, briefly, the applications realized in this institute by the technical group of CE. For example: nuclear reactor core design optimization, preventive maintenance scheduling optimizing and nuclear reactor transient identifications. It is also shown a novel computational tool to implementation of genetic algorithm that was development in this institute and applied in those works. Some results were presents and the gains obtained with the evolutionary computation were discussing. (author)

Using P300 to Evaluate the Effect of Object Color Knowledge in Novelty Detection

Directory of Open Access Journals (Sweden)

Mohammad Amin Khoshlessan1

2010-05-01

Full Text Available A B S T R A C T Introduction: In an oddball experiment, the context in which novel stimuli are presented affects characteristics of novelty P3, i.e. as long as there is a difficult task in which the difference between standard and target stimuli is small, recurrent presentation of a highly discrepant stimulus can lead to P300 highly similar to novelty P3. Effect of stimulus properties on P300 has also been previously examined and it has been shown that it plays a significant role in P300 topography, its amplitude and latency.Here we have examined the effect of surface color of objects of high color-diagnosticity in a visual oddball paradigm. Methods: In two separate conditions, we used pictures of fruits as target and novel stimuli. In condition one, novel stimuli were pictures of fruits in their canonical colors. In the second condition, novel stimuli were the same photo filtered to have a different non-canonical color. P300 was compared among these conditions. Results: Both target P3 and novelty P3 were detected in the two conditions but no significant difference was evident between conditions.Discussion: This result suggests that comparing to shape information; color cue does not play a significant role in detecting context novelty.

Neural and Environmental Factors Impacting Maternal Behavior Differences in High- versus Low-Novelty Seeking Rats

OpenAIRE

Clinton, Sarah M.; Bedrosian, Tracy A.; Abraham, Antony D.; Watson, Stanley J.; Akil, Huda

2010-01-01

Selective breeding of rats exhibiting differences in novelty-induced locomotion revealed that this trait predicts several differences in emotional behavior. Bred High Responders (bHRs) show exaggerated novelty-induced locomotion, aggression, and psychostimulant self-administration, compared to bred Low Responders (bLRs), which are inhibited and prone to anxiety- and depression-like behavior. Our breeding studies highlight the heritability of the bHR/bLR phenotypes, although environmental fact...

[Novelties in diagnostics and treatment of prostate cancer].

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Riesz, Péter; Nyírádi, Péter

2016-03-13

Similarly to earlier years, a vast majority of novel findings were published on prostate cancer, which is the most common urological cancer. Clinical trials with long-term follow-up and promising observational studies were published. In this paper the author reviews the relevant novelties including the diagnostic use of magnetic resonance imaging and positron emission tomography/computed tomography as well as active surveillance, cytoreductive prostatectomy and medical treatment.

Diversity, expansion, and evolutionary novelty of plant DNA-binding transcription factor families.

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Lehti-Shiu, Melissa D; Panchy, Nicholas; Wang, Peipei; Uygun, Sahra; Shiu, Shin-Han

2017-01-01

Plant transcription factors (TFs) that interact with specific sequences via DNA-binding domains are crucial for regulating transcriptional initiation and are fundamental to plant development and environmental response. In addition, expansion of TF families has allowed functional divergence of duplicate copies, which has contributed to novel, and in some cases adaptive, traits in plants. Thus, TFs are central to the generation of the diverse plant species that we see today. Major plant agronomic traits, including those relevant to domestication, have also frequently arisen through changes in TF coding sequence or expression patterns. Here our goal is to provide an overview of plant TF evolution by first comparing the diversity of DNA-binding domains and the sizes of these domain families in plants and other eukaryotes. Because TFs are among the most highly expanded gene families in plants, the birth and death process of TFs as well as the mechanisms contributing to their retention are discussed. We also provide recent examples of how TFs have contributed to novel traits that are important in plant evolution and in agriculture.This article is part of a Special Issue entitled: Plant Gene Regulatory Mechanisms and Networks, edited by Dr. Erich Grotewold and Dr. Nathan Springer. Copyright © 2016 Elsevier B.V. All rights reserved.

The place of development in mathematical evolutionary theory.

Science.gov (United States)

Rice, Sean H

2012-09-01

Development plays a critical role in structuring the joint offspring-parent phenotype distribution. It thus must be part of any truly general evolutionary theory. Historically, the offspring-parent distribution has often been treated in such a way as to bury the contribution of development, by distilling from it a single term, either heritability or additive genetic variance, and then working only with this term. I discuss two reasons why this approach is no longer satisfactory. First, the regression of expected offspring phenotype on parent phenotype can easily be nonlinear, and this nonlinearity can have a pronounced impact on the response to selection. Second, even when the offspring-parent regression is linear, it is nearly always a function of the environment, and the precise way that heritability covaries with the environment can have a substantial effect on adaptive evolution. Understanding these complexities of the offspring-parent distribution will require understanding of the developmental processes underlying the traits of interest. I briefly discuss how we can incorporate such complexity into formal evolutionary theory, and why it is likely to be important even for traits that are not traditionally the focus of evo-devo research. Finally, I briefly discuss a topic that is widely seen as being squarely in the domain of evo-devo: novelty. I argue that the same conceptual and mathematical framework that allows us to incorporate developmental complexity into simple models of trait evolution also yields insight into the evolution of novel traits. Copyright © 2011 Wiley Periodicals, Inc., A Wiley Company.

Novelty-seeking trait predicts the effect of methylphenidate on creativity.

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Gvirts, Hila Z; Mayseless, Naama; Segev, Aviv; Lewis, D Yael; Feffer, Kfir; Barnea, Yael; Bloch, Yuval; Shamay-Tsoory, Simon G

2017-05-01

In recent years the use of psychostimulants for cognitive enhancement in healthy individuals with no psychiatric disorders has been on the rise. However, it is still unclear whether psychostimulants improve certain cognitive functions at the cost of others, and how these psychostimulants interact with individual personality differences. In the current study, we investigated whether the effect of one common stimulant, methylphenidate (MPH), on creativity is associated with novelty seeking. Thirty-six healthy adults, without attention-deficit hyperactivity disorder (ADHD) symptomology, were assigned randomly in a double-blind fashion to receive MPH or placebo. We found that the effect of MPH on creativity was dependent on novelty-seeking (NS) personality characteristics of the participants. MPH increased creativity in individuals with lower NS, while it reduced creativity levels in individuals with high NS. These findings highlight the role of the dopaminergic system in creativity, and indicate that among healthy individuals NS can be seen as a predictor of the effect of MPH on creativity.

The evolutionary ecology of clonally propagated domesticated plants.

Science.gov (United States)

McKey, Doyle; Elias, Marianne; Pujol, Benoît; Duputié, Anne

2010-04-01

While seed-propagated crops have contributed many evolutionary insights, evolutionary biologists have often neglected clonally propagated crops. We argue that widespread notions about their evolution under domestication are oversimplified, and that they offer rich material for evolutionary studies. The diversity of their wild ancestors, the diverse ecologies of the crop populations themselves, and the intricate mix of selection pressures, acting not only on the parts harvested but also on the parts used by humans to make clonal propagules, result in complex and diverse evolutionary trajectories under domestication. We examine why farmers propagate some plants clonally, and discuss the evolutionary dynamics of sexual reproduction in clonal crops. We explore how their mixed clonal/sexual reproductive systems function, based on the sole example studied in detail, cassava (Manihot esculenta). Biotechnology is now expanding the number of clonal crops, continuing the 10 000-yr-old trend to increase crop yields by propagating elite genotypes. In an era of rapid global change, it is more important than ever to understand how the adaptive potential of clonal crops can be maintained. A key component of strategies for preserving this adaptive potential is the maintenance of mixed clonal/sexual systems, which can be achieved by encouraging and valuing farmer knowledge about the sexual reproductive biology of their clonal crops.

Turtles as hopeful monsters.

Science.gov (United States)

Rieppel, O

2001-11-01

A recently published study on the development of the turtle shell highlights the important role that development plays in the origin of evolutionary novelties. The evolution of the highly derived adult anatomy of turtles is a prime example of a macroevolutionary event triggered by changes in early embryonic development. Early ontogenetic deviation may cause patterns of morphological change that are not compatible with scenarios of gradualistic, stepwise transformation. Copyright 2001 John Wiley & Sons, Inc.

Design measures in evolutionary water cooled reactors to optimize for economic viability

International Nuclear Information System (INIS)

Oh, S.J.; Yu, S.K.W.; Appell, B.

1999-01-01

Since the mid 1980s, there have been various efforts to develop evolutionary water cooled reactors based on the current operating plant experience. To sustain and improve the economic viability, particular attention has been paid to the following aspects in developing evolutionary water cooled reactors: design simplification and increased operating margins, standardization in design as well as construction and operation, integration of operating plant insights, and consideration of safety, operability and constructability during the design stage. This paper reviews each item and discusses several examples from some of the evolutionary water cooled reactors being developed. (author)

[Evolutionary medicine: an introduction. Evolutionary biology, a missing element in medical teaching].

Science.gov (United States)

Swynghedauw, Bernard

2009-05-01

The aim of this brief review article is to help to reconcile medicine with evolutionary biology, a subject that should be taught in medical school. Evolutionary medicine takes the view that contemporary ills are related to an incompatibility between the environment in which humans currently live and their genomes, which have been shaped by diferent environmental conditions during biological evolution. Human activity has recently induced acute environmental modifications that have profoundly changed the medical landscape. Evolutionary biology is an irreversible, ongoing and discontinuous process characterized by periods of stasis followed by accelerations. Evolutionary biology is determined by genetic mutations, which are selected either by Darwinian selective pressure or randomly by genetic drift. Most medical events result from a genome/environment conflict. Some may be purely genetic, as in monogenic diseases, and others purely environmental, such as traffic accidents. Nevertheless, in most common diseases the clinical landscape is determined by the conflict between these two factors, the genetic elements of which are gradually being unraveled Three examples are examined in depth:--The medical consequences of the greenhouse effect. The absence of excess mortality during recent heat waves suggests that the main determinant of mortality in the 2003 heatwave was heatstroke and old age. The projected long-term effects of global warming call for research on thermolysis, a forgotten branch of physiology.--The hygiene hypothesis postulates that the exponential rise in autoimmune and allergic diseases is linked to lesser exposure to infectious agents, possibly involving counter-regulatory factors such as IL-10.--The recent rise in the incidence of obesity and type 2 diabetes in rich countries can be considered to result from a conflict between a calorie-rich environment and gene variants that control appetite. These variants are currently being identified by genome

Evolutionary change in physiological phenotypes along the human lineage.

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Vining, Alexander Q; Nunn, Charles L

2016-01-01

Research in evolutionary medicine provides many examples of how evolution has shaped human susceptibility to disease. Traits undergoing rapid evolutionary change may result in associated costs or reduce the energy available to other traits. We hypothesize that humans have experienced more such changes than other primates as a result of major evolutionary change along the human lineage. We investigated 41 physiological traits across 50 primate species to identify traits that have undergone marked evolutionary change along the human lineage. We analysed the data using two Bayesian phylogenetic comparative methods. One approach models trait covariation in non-human primates and predicts human phenotypes to identify whether humans are evolutionary outliers. The other approach models adaptive shifts under an Ornstein-Uhlenbeck model of evolution to assess whether inferred shifts are more common on the human branch than on other primate lineages. We identified four traits with strong evidence for an evolutionary increase on the human lineage (amylase, haematocrit, phosphorus and monocytes) and one trait with strong evidence for decrease (neutrophilic bands). Humans exhibited more cases of distinct evolutionary change than other primates. Human physiology has undergone increased evolutionary change compared to other primates. Long distance running may have contributed to increases in haematocrit and mean corpuscular haemoglobin concentration, while dietary changes are likely related to increases in amylase. In accordance with the pathogen load hypothesis, human monocyte levels were increased, but many other immune-related measures were not. Determining the mechanisms underlying conspicuous evolutionary change in these traits may provide new insights into human disease. The Author(s) 2016. Published by Oxford University Press on behalf of the Foundation for Evolution, Medicine, and Public Health.

Incorporating Development Into Evolutionary Psychology

Directory of Open Access Journals (Sweden)

David F. Bjorklund

2016-09-01

Full Text Available Developmental thinking is gradually becoming integrated within mainstream evolutionary psychology. This is most apparent with respect to the role of parenting, with proponents of life history theory arguing that cognitive and behavioral plasticity early in life permits children to select different life history strategies, with such strategies being adaptive solutions to different fitness trade-offs. I argue that adaptations develop and are based on the highly plastic nature of infants’ and children’s behavior/cognition/brains. The concept of evolved probabilistic cognitive mechanisms is introduced, defined as information processing mechanisms evolved to solve recurrent problems faced by ancestral populations that are expressed in a probabilistic fashion in each individual in a generation and are based on the continuous and bidirectional interaction over time at all levels of organization, from the genetic through the cultural. Early perceptual/cognitive biases result in behavior that, when occurring in a species-typical environment, produce continuous adaptive changes in behavior (and cognition, yielding adaptive outcomes. Examples from social learning and tool use are provided, illustrating the development of adaptations via evolved probabilistic cognitive mechanisms. The integration of developmental concepts into mainstream evolutionary psychology (and evolutionary concepts into mainstream developmental psychology will provide a clearer picture of what it means to be human.

Ontogenetic niche shifts and evolutionary branching in size-structured populations

NARCIS (Netherlands)

Claessen, D.; Dieckmann, U.

2002-01-01

There are many examples of size-structured populations where individuals sequentially exploit several niches in the course of their life history. Efficient exploitation of such ontogenetic niches generally requires specific morphological adaptations. Here, we study the evolutionary implications of

Animal regeneration: ancestral character or evolutionary novelty?

Science.gov (United States)

Slack, Jonathan Mw

2017-09-01

An old question about regeneration is whether it is an ancestral character which is a general property of living matter, or whether it represents a set of specific adaptations to the different circumstances faced by different types of animal. In this review, some recent results on regeneration are assessed to see if they can throw any new light on this question. Evidence in favour of an ancestral character comes from the role of Wnt and bone morphogenetic protein signalling in controlling the pattern of whole-body regeneration in acoels, which are a basal group of bilaterian animals. On the other hand, there is some evidence for adaptive acquisition or maintenance of the regeneration of appendages based on the occurrence of severe non-lethal predation, the existence of some novel genes in regenerating organisms, and differences at the molecular level between apparently similar forms of regeneration. It is tentatively concluded that whole-body regeneration is an ancestral character although has been lost from most animal lineages. Appendage regeneration is more likely to represent a derived character resulting from many specific adaptations. © 2017 The Author.

Uxoricide in pregnancy: ancient Greek domestic violence in evolutionary perspective.

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Deacy, Susan; McHardy, Fiona

2013-10-24

Previous studies of ancient Greek examples of uxoricide in pregnancy have concluded that the theme is used to suggest tyrannical abuse of power and that the violence is a product of the patriarchal nature of ancient society. This article uses evolutionary analyses of violence during pregnancy to argue that the themes of sexual jealousy and uncertainty over paternity are as crucial as the theme of power to an understanding of these examples and that the examples can be seen as typical instances of spousal abuse as it occurs in all types of society.

Past climate change on Sky Islands drives novelty in a core developmental gene network and its phenotype.

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Favé, Marie-Julie; Johnson, Robert A; Cover, Stefan; Handschuh, Stephan; Metscher, Brian D; Müller, Gerd B; Gopalan, Shyamalika; Abouheif, Ehab

2015-09-04

A fundamental and enduring problem in evolutionary biology is to understand how populations differentiate in the wild, yet little is known about what role organismal development plays in this process. Organismal development integrates environmental inputs with the action of gene regulatory networks to generate the phenotype. Core developmental gene networks have been highly conserved for millions of years across all animals, and therefore, organismal development may bias variation available for selection to work on. Biased variation may facilitate repeatable phenotypic responses when exposed to similar environmental inputs and ecological changes. To gain a more complete understanding of population differentiation in the wild, we integrated evolutionary developmental biology with population genetics, morphology, paleoecology and ecology. This integration was made possible by studying how populations of the ant species Monomorium emersoni respond to climatic and ecological changes across five 'Sky Islands' in Arizona, which are mountain ranges separated by vast 'seas' of desert. Sky Islands represent a replicated natural experiment allowing us to determine how repeatable is the response of M. emersoni populations to climate and ecological changes at the phenotypic, developmental, and gene network levels. We show that a core developmental gene network and its phenotype has kept pace with ecological and climate change on each Sky Island over the last ~90,000 years before present (BP). This response has produced two types of evolutionary change within an ant species: one type is unpredictable and contingent on the pattern of isolation of Sky lsland populations by climate warming, resulting in slight changes in gene expression, organ growth, and morphology. The other type is predictable and deterministic, resulting in the repeated evolution of a novel wingless queen phenotype and its underlying gene network in response to habitat changes induced by climate warming. Our

Memory effects of sleep, emotional valence, arousal and novelty in children

NARCIS (Netherlands)

Vermeulen, Marije C M; van der Heijden, Kristiaan B; Benjamins, Jeroen S; Swaab, Hanna; van Someren, Eus J W

Effectiveness of memory consolidation is determined by multiple factors, including sleep after learning, emotional valence, arousal and novelty. Few studies investigated how the effect of sleep compares with (and interacts with) these other factors, of which virtually none are in children. The

Memory effects of sleep, emotional valence, arousal and novelty in children

NARCIS (Netherlands)

Vermeulen, Marije C M; van der Heijden, Kristiaan B; Benjamins, Jeroen S.; Swaab, Hanna; Van Someren, Eus J W

2017-01-01

Effectiveness of memory consolidation is determined by multiple factors, including sleep after learning, emotional valence, arousal and novelty. Few studies investigated how the effect of sleep compares with (and interacts with) these other factors, of which virtually none are in children. The

The Role of Social Novelty in Risk Seeking and Exploratory Behavior: Implications for Addictions.

Science.gov (United States)

Mitchell, Simon; Gao, Jennifer; Hallett, Mark; Voon, Valerie

2016-01-01

Novelty preference or sensation seeking is associated with disorders of addiction and predicts rodent compulsive drug use and adolescent binge drinking in humans. Novelty has also been shown to influence choice in the context of uncertainty and reward processing. Here we introduce a novel or familiar neutral face stimuli and investigate its influence on risk-taking choices in healthy volunteers. We focus on behavioural outcomes and imaging correlates to the prime that might predict risk seeking. We hypothesized that subjects would be more risk seeking following a novel relative to familiar stimulus. We adapted a risk-taking task involving acceptance or rejection of a 50:50 choice of gain or loss that was preceded by a familiar (pre-test familiarization) or novel face prime. Neutral expression faces of males and females were used as primes. Twenty-four subjects were first tested behaviourally and then 18 scanned using a different variant of the same task under functional MRI. We show enhanced risk taking to both gain and loss anticipation following novel relative to familiar images and particularly for the low gain condition. Greater risk taking behaviour and self-reported exploratory behaviours was predicted by greater right ventral putaminal activity to novel versus familiar contexts. Social novelty appears to have a contextually enhancing effect on augmenting risky choices possibly mediated via ventral putaminal dopaminergic activity. Our findings link the observation that novelty preference and sensation seeking are important traits predicting the initiation and maintenance of risky behaviours, including substance and behavioural addictions.

Deficits in novelty exploration after controlled cortical impact.

Science.gov (United States)

Wagner, Amy K; Postal, Brett A; Darrah, Shaun D; Chen, Xiangbai; Khan, Amina S

2007-08-01

Experimental models of traumatic brain injury (TBI) have been utilized to characterize the behavioral derangements associated with brain trauma. Several studies exist characterizing motor function in the controlled cortical impact (CCI) injury model of TBI, but less research has focused on how CCI affects exploratory behavior. The goal of this study was to characterize deficits in three novelty exploration tasks after the CCI. Under anesthesia, 37 adult male Sprague Dawley rats received CCI (2.7 mm and 2.9 mm; 4 m/sec) over the right parietal cortex or sham surgery. For days 1-6 post-surgery, the beam balance and beam walking tasks were used to assess motor deficits. The Open Field, Y-Maze, and Free Choice Novelty (FCN) tasks were used to measure exploratory deficits from days 7-14 post-surgery. Injured rats displayed a significant, but transient, deficit on each motor task (p Open Field results showed that injured rats had lower activity levels than shams (p time in the novel arm versus the familiar arms when compared to shams (p time and had fewer interactions with objects in the novel environment compared to shams (p < 0.05). These results suggest that several ethological factors contribute to exploratory deficits after CCI and can be effectively characterized with the behavioral tasks described. Future work will utilize these tasks to evaluate the neural substrates underlying exploratory deficits after TBI.

Assessing fluctuating evolutionary pressure in yeast and mammal evolutionary rate covariation using bioinformatics of meiotic protein genetic sequences

Science.gov (United States)

Dehipawala, Sunil; Nguyen, A.; Tremberger, G.; Cheung, E.; Holden, T.; Lieberman, D.; Cheung, T.

2013-09-01

The evolutionary rate co-variation in meiotic proteins has been reported for yeast and mammal using phylogenic branch lengths which assess retention, duplication and mutation. The bioinformatics of the corresponding DNA sequences could be classified as a diagram of fractal dimension and Shannon entropy. Results from biomedical gene research provide examples on the diagram methodology. The identification of adaptive selection using entropy marker and functional-structural diversity using fractal dimension would support a regression analysis where the coefficient of determination would serve as evolutionary pathway marker for DNA sequences and be an important component in the astrobiology community. Comparisons between biomedical genes such as EEF2 (elongation factor 2 human, mouse, etc), WDR85 in epigenetics, HAR1 in human specificity, clinical trial targeted cancer gene CD47, SIRT6 in spermatogenesis, and HLA-C in mosquito bite immunology demonstrate the diagram classification methodology. Comparisons to the SEPT4-XIAP pair in stem cell apoptosis, testesexpressed taste genes TAS1R3-GNAT3 pair, and amyloid beta APLP1-APLP2 pair with the yeast-mammal DNA sequences for meiotic proteins RAD50-MRE11 pair and NCAPD2-ICK pair have accounted for the observed fluctuating evolutionary pressure systematically. Regression with high R-sq values or a triangular-like cluster pattern for concordant pairs in co-variation among the studied species could serve as evidences for the possible location of common ancestors in the entropy-fractal dimension diagram, consistent with an example of the human-chimp common ancestor study using the FOXP2 regulated genes reported in human fetal brain study. The Deinococcus radiodurans R1 Rad-A could be viewed as an outlier in the RAD50 diagram and also in the free energy versus fractal dimension regression Cook's distance, consistent with a non-Earth source for this radiation resistant bacterium. Convergent and divergent fluctuating evolutionary

Human Novelty Response to Emotional Animal Vocalizations: Effects of Phylogeny and Familiarity

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Marina Scheumann

2017-10-01

Full Text Available Darwin (1872 postulated that emotional expressions contain universals that are retained across species. We recently showed that human rating responses were strongly affected by a listener's familiarity with vocalization types, whereas evidence for universal cross-taxa emotion recognition was limited. To disentangle the impact of evolutionarily retained mechanisms (phylogeny and experience-driven cognitive processes (familiarity, we compared the temporal unfolding of event-related potentials (ERPs in response to agonistic and affiliative vocalizations expressed by humans and three animal species. Using an auditory oddball novelty paradigm, ERPs were recorded in response to task-irrelevant novel sounds, comprising vocalizations varying in their degree of phylogenetic relationship and familiarity to humans. Vocalizations were recorded in affiliative and agonistic contexts. Offline, participants rated the vocalizations for valence, arousal, and familiarity. Correlation analyses revealed a significant correlation between a posteriorly distributed early negativity and arousal ratings. More specifically, a contextual category effect of this negativity was observed for human infant and chimpanzee vocalizations but absent for other species vocalizations. Further, a significant correlation between the later and more posteriorly P3a and P3b responses and familiarity ratings indicates a link between familiarity and attentional processing. A contextual category effect of the P3b was observed for the less familiar chimpanzee and tree shrew vocalizations. Taken together, these findings suggest that early negative ERP responses to agonistic and affiliative vocalizations may be influenced by evolutionary retained mechanisms, whereas the later orienting of attention (positive ERPs may mainly be modulated by the prior experience.

Ecological and evolutionary consequences of niche construction for its agent.

Science.gov (United States)

Kylafis, Grigoris; Loreau, Michel

2008-10-01

Niche construction can generate ecological and evolutionary feedbacks that have been underinvestigated so far. We present an eco-evolutionary model that incorporates the process of niche construction to reveal its effects on the ecology and evolution of the niche-constructing agent. We consider a simple plant-soil nutrient ecosystem in which plants have the ability to increase the input of inorganic nutrient as an example of positive niche construction. On an ecological time scale, the model shows that niche construction allows the persistence of plants under infertile soil conditions that would otherwise lead to their extinction. This expansion of plants' niche, however, requires a high enough rate of niche construction and a high enough initial plant biomass to fuel the positive ecological feedback between plants and their soil environment. On an evolutionary time scale, we consider that the rates of niche construction and nutrient uptake coevolve in plants while a trade-off constrains their values. Different evolutionary outcomes are possible depending on the shape of the trade-off. We show that niche construction results in an evolutionary feedback between plants and their soil environment such that plants partially regulate soil nutrient content. The direct benefit accruing to plants, however, plays a crucial role in the evolutionary advantage of niche construction.

Economic competitiveness requirements for evolutionary water cooled reactors

International Nuclear Information System (INIS)

Hudson, C.R.; Bertel, E.; Paik, K.H.; Roh, J.H.; Tort, V.

1999-01-01

This paper analyses the necessary economic conditions for evolutionary water cooled reactors to be competitive. Utilising recent national cost data for fossil-fired base load plants expected to be commissioned by 2005 -2010, target costs for nuclear power plants are discussed. Factors that could contribute to the achievement of those targets by evolutionary water cooled reactors are addressed. The feed-back from experience acquired in implementing nuclear programmes is illustrated by some examples from France and the Republic of Korea. The paper discusses the impacts on nuclear power competitiveness of globalisation and deregulation of the electricity market and privatisation of the electricity sector. In addition, issues related to external cost internalisation are considered. (author)

General upper bounds on the runtime of parallel evolutionary algorithms.

Science.gov (United States)

Lässig, Jörg; Sudholt, Dirk

2014-01-01

We present a general method for analyzing the runtime of parallel evolutionary algorithms with spatially structured populations. Based on the fitness-level method, it yields upper bounds on the expected parallel runtime. This allows for a rigorous estimate of the speedup gained by parallelization. Tailored results are given for common migration topologies: ring graphs, torus graphs, hypercubes, and the complete graph. Example applications for pseudo-Boolean optimization show that our method is easy to apply and that it gives powerful results. In our examples the performance guarantees improve with the density of the topology. Surprisingly, even sparse topologies such as ring graphs lead to a significant speedup for many functions while not increasing the total number of function evaluations by more than a constant factor. We also identify which number of processors lead to the best guaranteed speedups, thus giving hints on how to parameterize parallel evolutionary algorithms.

An Evolutionary Framework for Understanding the Origin of Eukaryotes

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Neil W. Blackstone

2016-04-01

Full Text Available Two major obstacles hinder the application of evolutionary theory to the origin of eukaryotes. The first is more apparent than real—the endosymbiosis that led to the mitochondrion is often described as “non-Darwinian” because it deviates from the incremental evolution championed by the modern synthesis. Nevertheless, endosymbiosis can be accommodated by a multi-level generalization of evolutionary theory, which Darwin himself pioneered. The second obstacle is more serious—all of the major features of eukaryotes were likely present in the last eukaryotic common ancestor thus rendering comparative methods ineffective. In addition to a multi-level theory, the development of rigorous, sequence-based phylogenetic and comparative methods represents the greatest achievement of modern evolutionary theory. Nevertheless, the rapid evolution of major features in the eukaryotic stem group requires the consideration of an alternative framework. Such a framework, based on the contingent nature of these evolutionary events, is developed and illustrated with three examples: the putative intron proliferation leading to the nucleus and the cell cycle; conflict and cooperation in the origin of eukaryotic bioenergetics; and the inter-relationship between aerobic metabolism, sterol synthesis, membranes, and sex. The modern synthesis thus provides sufficient scope to develop an evolutionary framework to understand the origin of eukaryotes.

Broken Expectations: Violation of Expectancies, Not Novelty, Captures Auditory Attention

Science.gov (United States)

Vachon, Francois; Hughes, Robert W.; Jones, Dylan M.

2012-01-01

The role of memory in behavioral distraction by auditory attentional capture was investigated: We examined whether capture is a product of the novelty of the capturing event (i.e., the absence of a recent memory for the event) or its violation of learned expectancies on the basis of a memory for an event structure. Attentional capture--indicated…

Eco-evolutionary spatial dynamics in the Glanville fritillary butterfly.

Science.gov (United States)

Hanski, Ilkka A

2011-08-30

Demographic population dynamics, gene flow, and local adaptation may influence each other and lead to coupling of ecological and evolutionary dynamics, especially in species inhabiting fragmented heterogeneous environments. Here, I review long-term research on eco-evolutionary spatial dynamics in the Glanville fritillary butterfly inhabiting a large network of approximately 4,000 meadows in Finland. The metapopulation persists in a balance between frequent local extinctions and recolonizations. The genetic spatial structure as defined by neutral markers is much more coarse-grained than the demographic spatial structure determined by the fragmented habitat, yet small-scale spatial structure has important consequences for the dynamics. I discuss three examples of eco-evolutionary spatial dynamics. (i) Extinction-colonization metapopulation dynamics influence allele frequency changes in the phosphoglucose isomerase (Pgi) gene, which leads to strong associations between genetic variation in Pgi and dispersal, recolonization, and local population dynamics. (ii) Inbreeding in local populations increases their risk for extinction, whereas reciprocal effects between inbreeding, population size, and emigration represent likely eco-evolutionary feedbacks. (iii) Genetically determined female oviposition preference for two host plant species exhibits a cline paralleling a gradient in host plant relative abundances, and host plant preference of dispersing females in relation to the host plant composition of habitat patches influences immigration (gene flow) and recolonization (founder events). Eco-evolutionary spatial dynamics in heterogeneous environments may not lead to directional evolutionary changes unless the environment itself changes, but eco-evolutionary dynamics may contribute to the maintenance of genetic variation attributable to fluctuating selection in space and time.

Involvement of the oxytocin system in the nucleus accumbens in the regulation of juvenile social novelty-seeking behavior.

Science.gov (United States)

Smith, Caroline J W; Mogavero, Jazmin N; Tulimieri, Maxwell T; Veenema, Alexa H

2017-07-01

Exploration of novel environments, stimuli, and conspecifics is highly adaptive during the juvenile period, as individuals transition from immaturity to adulthood. We recently showed that juvenile rats prefer to interact with a novel individual over a familiar cage mate. However, the neural mechanisms underlying this juvenile social novelty-seeking behavior remain largely unknown. One potential candidate is the oxytocin (OXT) system, given its involvement in various motivated social behaviors. Here, we show that administration of the specific oxytocin receptor antagonist desGly-NH 2 ,d(CH 2 ) 5 -[Tyr(Me) 2 ,Thr 4 ]OVT reduces social novelty seeking-behavior in juvenile male rats when injected into the nucleus accumbens (10ng/0.5μl/side). The same drug dose was ineffective at altering social novelty-seeking behavior when administered into the lateral septum or basolateral amygdala. These results are the first to suggest the involvement of the OXT system in the nucleus accumbens in the regulation of juvenile social novelty-seeking behavior. Copyright © 2017 Elsevier Inc. All rights reserved.

Examples of equilibrium and non-equilibrium behavior in evolutionary systems

Science.gov (United States)

Soulier, Arne

With this thesis, we want to shed some light into the darkness of our understanding of simply defined statistical mechanics systems and the surprisingly complex dynamical behavior they exhibit. We will do so by presenting in turn one equilibrium and then one non-equilibrium system with evolutionary dynamics. In part 1, we will present the seceder-model, a newly developed system that cannot equilibrate. We will then study several properties of the system and obtain an idea of the richness of the dynamics of the seceder model, which is particular impressive given the minimal amount of modeling necessary in its setup. In part 2, we will present extensions to the directed polymer in random media problem on a hypercube and its connection to the Eigen model of evolution. Our main interest will be the influence of time-dependent and time-independent changes in the fitness landscape viewed by an evolving population. This part contains the equilibrium dynamics. The stochastic models and the topic of evolution and non-equilibrium in general will allow us to point out similarities to the various lines of thought in game theory.

On Reciprocal Causation in the Evolutionary Process.

Science.gov (United States)

Svensson, Erik I

2018-01-01

Recent calls for a revision of standard evolutionary theory (SET) are based partly on arguments about the reciprocal causation. Reciprocal causation means that cause-effect relationships are bi-directional, as a cause could later become an effect and vice versa. Such dynamic cause-effect relationships raise questions about the distinction between proximate and ultimate causes, as originally formulated by Ernst Mayr. They have also motivated some biologists and philosophers to argue for an Extended Evolutionary Synthesis (EES). The EES will supposedly expand the scope of the Modern Synthesis (MS) and SET, which has been characterized as gene-centred, relying primarily on natural selection and largely neglecting reciprocal causation. Here, I critically examine these claims, with a special focus on the last conjecture. I conclude that reciprocal causation has long been recognized as important by naturalists, ecologists and evolutionary biologists working in the in the MS tradition, although it it could be explored even further. Numerous empirical examples of reciprocal causation in the form of positive and negative feedback are now well known from both natural and laboratory systems. Reciprocal causation have also been explicitly incorporated in mathematical models of coevolutionary arms races, frequency-dependent selection, eco-evolutionary dynamics and sexual selection. Such dynamic feedback were already recognized by Richard Levins and Richard Lewontin in their bok The Dialectical Biologist . Reciprocal causation and dynamic feedback might also be one of the few contributions of dialectical thinking and Marxist philosophy in evolutionary theory. I discuss some promising empirical and analytical tools to study reciprocal causation and the implications for the EES. Finally, I briefly discuss how quantitative genetics can be adapated to studies of reciprocal causation, constructive inheritance and phenotypic plasticity and suggest that the flexibility of this approach

Enhancing Evolutionary Optimization in Uncertain Environments by Allocating Evaluations via Multi-armed Bandit Algorithms

OpenAIRE

Qiu, Xin; Miikkulainen, Risto

2018-01-01

Optimization problems with uncertain fitness functions are common in the real world, and present unique challenges for evolutionary optimization approaches. Existing issues include excessively expensive evaluation, lack of solution reliability, and incapability in maintaining high overall fitness during optimization. Using conversion rate optimization as an example, this paper proposes a series of new techniques for addressing these issues. The main innovation is to augment evolutionary algor...

Novelty detection of foreign objects in food using multi-modal X-ray imaging

DEFF Research Database (Denmark)

Einarsdottir, Hildur; Emerson, Monica Jane; Clemmensen, Line Katrine Harder

2016-01-01

In this paper we demonstrate a method for novelty detection of foreign objects in food products using grating-based multimodal X-ray imaging. With this imaging technique three modalities are available with pixel correspondence, enhancing organic materials such as wood chips, insects and soft...... plastics not detectable by conventional X-ray absorption radiography. We conduct experiments, where several food products are imaged with common foreign objects typically found in the food processing industry. To evaluate the benefit from using this multi-contrast X-ray technique over conventional X......-ray absorption imaging, a novelty detection scheme based on well known image- and statistical analysis techniques is proposed. The results show that the presented method gives superior recognition results and highlights the advantage of grating-based imaging....

Novelty exposure overcomes foot shock-induced spatial-memory impairment by processes of synaptic-tagging in rats

OpenAIRE

Almaguer-Melian, William; Bergado-Rosado, Jorge; Pavón-Fuentes, Nancy; Alberti-Amador, Esteban; Mercerón-Martínez, Daymara; Frey, Julietta U.

2012-01-01

Novelty processing can transform short-term into long-term memory. We propose that this memory-reinforcing effect of novelty could be explained by mechanisms outlined in the “synaptic tagging hypothesis.” Initial short-term memory is sustained by a transient plasticity change at activated synapses and sets synaptic tags. These tags are later able to capture and process the plasticity-related proteins (PRPs), which are required to transform a short-term synaptic change into a long-term one. No...

Heterogeneous update mechanisms in evolutionary games: Mixing innovative and imitative dynamics

Science.gov (United States)

Amaral, Marco Antonio; Javarone, Marco Alberto

2018-04-01

Innovation and evolution are two processes of paramount relevance for social and biological systems. In general, the former allows the introduction of elements of novelty, while the latter is responsible for the motion of a system in its phase space. Often, these processes are strongly related, since an innovation can trigger the evolution, and the latter can provide the optimal conditions for the emergence of innovations. Both processes can be studied by using the framework of evolutionary game theory, where evolution constitutes an intrinsic mechanism. At the same time, the concept of innovation requires an opportune mathematical representation. Notably, innovation can be modeled as a strategy, or it can constitute the underlying mechanism that allows agents to change strategy. Here, we analyze the second case, investigating the behavior of a heterogeneous population, composed of imitative and innovative agents. Imitative agents change strategy only by imitating that of their neighbors, whereas innovative ones change strategy without the need for a copying source. The proposed model is analyzed by means of analytical calculations and numerical simulations in different topologies. Remarkably, results indicate that the mixing of mechanisms can be detrimental to cooperation near phase transitions. In those regions, the spatial reciprocity from imitative mechanisms is destroyed by innovative agents, leading to the downfall of cooperation. Our investigation sheds some light on the complex dynamics emerging from the heterogeneity of strategy revision methods, highlighting the role of innovation in evolutionary games.

Evolutionary Nephrology.

Science.gov (United States)

Chevalier, Robert L

2017-05-01

Progressive kidney disease follows nephron loss, hyperfiltration, and incomplete repair, a process described as "maladaptive." In the past 20 years, a new discipline has emerged that expands research horizons: evolutionary medicine. In contrast to physiologic (homeostatic) adaptation, evolutionary adaptation is the result of reproductive success that reflects natural selection. Evolutionary explanations for physiologically maladaptive responses can emerge from mismatch of the phenotype with environment or evolutionary tradeoffs. Evolutionary adaptation to a terrestrial environment resulted in a vulnerable energy-consuming renal tubule and a hypoxic, hyperosmolar microenvironment. Natural selection favors successful energy investment strategy: energy is allocated to maintenance of nephron integrity through reproductive years, but this declines with increasing senescence after ~40 years of age. Risk factors for chronic kidney disease include restricted fetal growth or preterm birth (life history tradeoff resulting in fewer nephrons), evolutionary selection for APOL1 mutations (that provide resistance to trypanosome infection, a tradeoff), and modern life experience (Western diet mismatch leading to diabetes and hypertension). Current advances in genomics, epigenetics, and developmental biology have revealed proximate causes of kidney disease, but attempts to slow kidney disease remain elusive. Evolutionary medicine provides a complementary approach by addressing ultimate causes of kidney disease. Marked variation in nephron number at birth, nephron heterogeneity, and changing susceptibility to kidney injury throughout life history are the result of evolutionary processes. Combined application of molecular genetics, evolutionary developmental biology (evo-devo), developmental programming and life history theory may yield new strategies for prevention and treatment of chronic kidney disease.

Evolutionary Nephrology

Directory of Open Access Journals (Sweden)

Robert L. Chevalier

2017-05-01

Full Text Available Progressive kidney disease follows nephron loss, hyperfiltration, and incomplete repair, a process described as “maladaptive.” In the past 20 years, a new discipline has emerged that expands research horizons: evolutionary medicine. In contrast to physiologic (homeostatic adaptation, evolutionary adaptation is the result of reproductive success that reflects natural selection. Evolutionary explanations for physiologically maladaptive responses can emerge from mismatch of the phenotype with environment or from evolutionary tradeoffs. Evolutionary adaptation to a terrestrial environment resulted in a vulnerable energy-consuming renal tubule and a hypoxic, hyperosmolar microenvironment. Natural selection favors successful energy investment strategy: energy is allocated to maintenance of nephron integrity through reproductive years, but this declines with increasing senescence after ∼40 years of age. Risk factors for chronic kidney disease include restricted fetal growth or preterm birth (life history tradeoff resulting in fewer nephrons, evolutionary selection for APOL1 mutations (which provide resistance to trypanosome infection, a tradeoff, and modern life experience (Western diet mismatch leading to diabetes and hypertension. Current advances in genomics, epigenetics, and developmental biology have revealed proximate causes of kidney disease, but attempts to slow kidney disease remain elusive. Evolutionary medicine provides a complementary approach by addressing ultimate causes of kidney disease. Marked variation in nephron number at birth, nephron heterogeneity, and changing susceptibility to kidney injury throughout the life history are the result of evolutionary processes. Combined application of molecular genetics, evolutionary developmental biology (evo-devo, developmental programming, and life history theory may yield new strategies for prevention and treatment of chronic kidney disease.

Aesthetic Emotions and Aesthetic People: Openness Predicts Sensitivity to Novelty in the Experiences of Interest and Pleasure

Directory of Open Access Journals (Sweden)

Kirill eFayn

2015-12-01

Full Text Available There is a stable relationship between the Openness/Intellect domain of personality and aesthetic engagement. However, neither of these are simple constructs and while the relationship exists process based evidence explaining the relationship is still lacking. The current research looked to clarify the relationship by evaluating the influence of the Openness and Intellect aspects on several different aesthetic emotions. Two studies looked at the between- and within-person differences in the emotions of interest, pleasure and confusion in response to visual art. The results suggest that Openness, as opposed to Intellect, was predictive of greater interest and pleasure, while both aspects explained less confusion. Differences in Openness were associated with within-person emotion appraisal contingencies, particularly greater novelty-interest and novelty-pleasure relationships. Those higher in Openness were particularly influenced by novelty in artworks. For pleasure this relationship suggested a different qualitative structure of appraisals. The appraisal of novelty is part of the experience of pleasure for those high in Openness, but not those low in Openness. This research supports the utility of studying Openness and Intellect as separate aspects of the broad domain and clarifies the relationship between Openness and aesthetic states in terms of within-person appraisal processes.

Novelties in the genus Persicaria (Polygonaceae) in Brazil

DEFF Research Database (Denmark)

Funez, Luís A.; Hassemer, Gustavo

2018-01-01

This work presents novelties in the genus Persicaria in Brazil. More specifically, we describe P. sylvestris, a new species from the Atlantic rainforest in subtropical Brazil, propose the new combination P. diospyrifolium and designate a lectotype for its basionym, Polygonum diospyrifolium. The new...... species has until now been identified as P. acuminata, from which it differs by morphological characters as well as ecological aspects. We also provide photographs of the new species and of similar species along with a distribution map and a key to the species of Persicaria in Brazil....

Evolutionary competition between boundedly rational behavioral rules in oligopoly games

International Nuclear Information System (INIS)

Cerboni Baiardi, Lorenzo; Lamantia, Fabio; Radi, Davide

2015-01-01

In this paper, we propose an evolutionary model of oligopoly competition where agents can select between different behavioral rules to make decisions on productions. We formalize the model as a general class of evolutionary oligopoly games and then we consider an example with two specific rules, namely Local Monopolistic Approximation and Gradient dynamics. We provide several results on the global dynamic properties of the model, showing that in some cases the attractor of the system may belong to an invariant plane where only one behavioral rule is adopted (monomorphic state). The attractors on the invariant planes can be either strong attractors or weak attractors. However, we also explain why the system can be in a state of Evolutionary Stable Heterogeneity, where it is more profitable for the agents to employ both heuristics in the long term (polymorphic state).

Artificial domain duplication replicates evolutionary history of ketol-acid reductoisomerases.

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Cahn, Jackson K B; Brinkmann-Chen, Sabine; Buller, Andrew R; Arnold, Frances H

2016-07-01

The duplication of protein structural domains has been proposed as a common mechanism for the generation of new protein folds. A particularly interesting case is the class II ketol-acid reductoisomerase (KARI), which putatively arose from an ancestral class I KARI by duplication of the C-terminal domain and corresponding loss of obligate dimerization. As a result, the class II enzymes acquired a deeply embedded figure-of-eight knot. To test this evolutionary hypothesis we constructed a novel class II KARI by duplicating the C-terminal domain of a hyperthermostable class I KARI. The new protein is monomeric, as confirmed by gel filtration and X-ray crystallography, and has the deeply knotted class II KARI fold. Surprisingly, its catalytic activity is nearly unchanged from the parent KARI. This provides strong evidence in support of domain duplication as the mechanism for the evolution of the class II KARI fold and demonstrates the ability of domain duplication to generate topological novelty in a function-neutral manner. © 2015 The Protein Society.

Novelty Detection for Interactive Pose Recognition by a Social Robot

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Victor Gonzalez-Pacheco

2015-04-01

Full Text Available Active robot learners take an active role in their own learning by making queries to their human teachers when they receive new data. However, not every received input is useful for the robot, and asking for non-informative inputs or asking too many questions might worsen the user's perception of the robot. We present a novelty detection system that enables a robot to ask labels for new stimuli only when they seem both novel and interesting. Our system separates the decision process into two steps: first, it discriminates novel from known stimuli, and second, it estimates if these stimuli are likely to happen again. Our approach uses the notion of curiosity, which controls the eagerness with which the robot asks questions to the user. We evaluate our approach in the domain of pose learning by training our robot with a set of pointing poses able to detect up to 84%, 79%, and 78% of the observed novelties in three different experiments. Our approach enables robots to keep learning continuously, even after training is finished. The introduction of the curiosity parameter allows tuning, for the conditions in which the robot should want to learn more.

Evolutionary history of the porpoise family (Phocoenidae) : A perspective from mitogenomes

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Ben Chehida, Yacine; Aguilar, A. A.; Borrell, A.; Ferreira, M.; Taylor, B.L.; Rojas-Bracho, L.; Robertson, K.; Thumloup, Julie; Schumacher, C.; Vikingsson, G.A.; Morin, Phillip A.; Fontaine, Michael Christophe

2017-01-01

The six species of porpoises inhabit the cold waters of the globe, displaying a textbook example of anti-tropical distribution in marine mammals. Nevertheless, the evolutionary history of the porpoises still remained poorly understood, but this knowledge is crucial to illuminate the conservation

Evolutionary game theory using agent-based methods.

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Adami, Christoph; Schossau, Jory; Hintze, Arend

2016-12-01

Evolutionary game theory is a successful mathematical framework geared towards understanding the selective pressures that affect the evolution of the strategies of agents engaged in interactions with potential conflicts. While a mathematical treatment of the costs and benefits of decisions can predict the optimal strategy in simple settings, more realistic settings such as finite populations, non-vanishing mutations rates, stochastic decisions, communication between agents, and spatial interactions, require agent-based methods where each agent is modeled as an individual, carries its own genes that determine its decisions, and where the evolutionary outcome can only be ascertained by evolving the population of agents forward in time. While highlighting standard mathematical results, we compare those to agent-based methods that can go beyond the limitations of equations and simulate the complexity of heterogeneous populations and an ever-changing set of interactors. We conclude that agent-based methods can predict evolutionary outcomes where purely mathematical treatments cannot tread (for example in the weak selection-strong mutation limit), but that mathematics is crucial to validate the computational simulations. Copyright © 2016 Elsevier B.V. All rights reserved.

Resistance and relatedness on an evolutionary graph

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Maciejewski, Wes

2012-01-01

When investigating evolution in structured populations, it is often convenient to consider the population as an evolutionary graph—individuals as nodes, and whom they may act with as edges. There has, in recent years, been a surge of interest in evolutionary graphs, especially in the study of the evolution of social behaviours. An inclusive fitness framework is best suited for this type of study. A central requirement for an inclusive fitness analysis is an expression for the genetic similarity between individuals residing on the graph. This has been a major hindrance for work in this area as highly technical mathematics are often required. Here, I derive a result that links genetic relatedness between haploid individuals on an evolutionary graph to the resistance between vertices on a corresponding electrical network. An example that demonstrates the potential computational advantage of this result over contemporary approaches is provided. This result offers more, however, to the study of population genetics than strictly computationally efficient methods. By establishing a link between gene transfer and electric circuit theory, conceptualizations of the latter can enhance understanding of the former. PMID:21849384

Evolutionary molecular medicine.

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Nesse, Randolph M; Ganten, Detlev; Gregory, T Ryan; Omenn, Gilbert S

2012-05-01

Evolution has long provided a foundation for population genetics, but some major advances in evolutionary biology from the twentieth century that provide foundations for evolutionary medicine are only now being applied in molecular medicine. They include the need for both proximate and evolutionary explanations, kin selection, evolutionary models for cooperation, competition between alleles, co-evolution, and new strategies for tracing phylogenies and identifying signals of selection. Recent advances in genomics are transforming evolutionary biology in ways that create even more opportunities for progress at its interfaces with genetics, medicine, and public health. This article reviews 15 evolutionary principles and their applications in molecular medicine in hopes that readers will use them and related principles to speed the development of evolutionary molecular medicine.

Enhancing offspring hypothalamic-pituitary-adrenal (HPA regulation via systematic neonatal novelty exposure: the influence of maternal HPA function

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Sarah M. Dinces

2014-06-01

Full Text Available In the rat, repeated brief exposures to novelty early in life can induce long-lasting enhancements in adult cognitive, social, emotional, and neuroendocrine function. Family-to-family variations in these intervention effects on adult offspring are predicted by the mother’s ability to mount a rapid corticosterone (CORT response to the onset of an acute stressor. Here, in Long-Evans rats, we investigated whether neonatal and adulthood novelty exposure, each individually and in combination, can enhance offspring HPA regulation. Using a 2x2 within-litter design, one half of each litter were exposed to a relatively novel non-home environment for 3-min (Neo_Novel daily during infancy (PND1-21 and the other half of the litter remained in the home cage (Neo_Home; we further exposed half of these two groups to early adulthood (PND54-63 novelty exposure in an open field and the remaining siblings stayed in their home cages. Two aspects of HPA regulation were assessed: the ability to maintain a low level of resting CORT (CORTB and the ability to mount a large rapid CORT response (CORTE to the onset of an acute stressor. Assessment of adult offspring’s ability to regulate HPA regulation began at 370 days of age. We further investigated whether the novelty exposure effects on offspring HPA regulation are sensitive to the context of maternal HPA regulation by assessing maternal HPA regulation similarly beginning 7 days after her pups were weaned. We found that at the population level, rats receiving neonatal, but not early adulthood exposure or both, showed a greater rapid CORTE than their home-staying siblings. At the individual family level, these novelty effects are positively associated with maternal CORTE. These results suggest that early experience of novelty can enhance the offspring’s ability to mount a rapid response to environmental challenge and the success of such early life intervention is critically dependent upon the context of maternal

On the numerical treatment of selected oscillatory evolutionary problems

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Cardone, Angelamaria; Conte, Dajana; D'Ambrosio, Raffaele; Paternoster, Beatrice

2017-07-01

We focus on evolutionary problems whose qualitative behaviour is known a-priori and exploited in order to provide efficient and accurate numerical schemes. For classical numerical methods, depending on constant coefficients, the required computational effort could be quite heavy, due to the necessary employ of very small stepsizes needed to accurately reproduce the qualitative behaviour of the solution. In these situations, it may be convenient to use special purpose formulae, i.e. non-polynomially fitted formulae on basis functions adapted to the problem (see [16, 17] and references therein). We show examples of special purpose strategies to solve two families of evolutionary problems exhibiting periodic solutions, i.e. partial differential equations and Volterra integral equations.

Novelty preference in patients with developmental amnesia.

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Munoz, M; Chadwick, M; Perez-Hernandez, E; Vargha-Khadem, F; Mishkin, M

2011-12-01

To re-examine whether or not selective hippocampal damage reduces novelty preference in visual paired comparison (VPC), we presented two different versions of the task to a group of patients with developmental amnesia (DA), each of whom sustained this form of pathology early in life. Compared with normal control participants, the DA group showed a delay-dependent reduction in novelty preference on one version of the task and an overall reduction on both versions combined. Because VPC is widely considered to be a measure of incidental recognition, the results appear to support the view that the hippocampus contributes to recognition memory. A difficulty for this conclusion, however, is that according to one current view the hippocampal contribution to recognition is limited to task conditions that encourage recollection of an item in some associated context, and according to another current view, to recognition of an item with the high confidence judgment that reflects a strong memory. By contrast, VPC, throughout which the participant remains entirely uninstructed other than to view the stimuli, would seem to lack such task conditions and so would likely lead to recognition based on familiarity rather than recollection or, alternatively, weak memories rather than strong. However, before concluding that the VPC impairment therefore contradicts both current views regarding the role of the hippocampus in recognition memory, two possibilities that would resolve this issue need to be investigated. One is that some variable in VPC, such as the extended period of stimulus encoding during familiarization, overrides its incidental nature, and, because this condition promotes either recollection- or strength-based recognition, renders the task hippocampal-dependent. The other possibility is that VPC, rather than providing a measure of incidental recognition, actually assesses an implicit, information-gathering process modulated by habituation, for which the hippocampus is

Differential effects of social and novelty enrichment on individual differences in impulsivity and behavioral flexibility.

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Wang, Maya Zhe; Marshall, Andrew T; Kirkpatrick, Kimberly

2017-06-01

Early life experience profoundly impacts behavior and cognitive functions in rats. The present study investigated how the presence of conspecifics and/or novel objects, could independently influence individual differences in impulsivity and behavioral flexibility. Twenty-four rats were reared in an isolated condition, an isolated condition with a novel object, a pair-housed social condition, or a pair-housed social condition with a novel object. The rats were then tested on an impulsive choice task, a behavioral flexibility task, and an impulsive action task. Novelty enrichment produced an overall increase in impulsive choice, while social enrichment decreased impulsive choice in the absence of novelty enrichment and also produced an overall increase in impulsive action. In the behavioral flexibility task, social enrichment increased regressive errors, whereas both social and novelty enrichment reduced never-reinforced errors. Individual differences analyses indicated a significant relationship between performance in the behavioral flexibility and impulsive action tasks, which may reflect a common psychological correlate of action inhibition. Moreover, there was a relationship between delay sensitivity in the impulsive choice task and performance on the DRL and behavioral flexibility tasks, suggesting a dual role for timing and inhibitory processes in driving the interrelationship between these tasks. Overall, these results indicate that social and novelty enrichment produce distinct effects on impulsivity and adaptability, suggesting the need to parse out the different elements of enrichment in future studies. Further research is warranted to better understand how individual differences in sensitivity to enrichment affect individuals' interactions with and the resulting consequences of the rearing environment. Copyright © 2017 Elsevier B.V. All rights reserved.

Most Colorful Example of Genetic Assimilation? Exploring the Evolutionary Destiny of Recurrent Phenotypic Accommodation.

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Badyaev, Alexander V; Potticary, Ahva L; Morrison, Erin S

2017-08-01

Evolution of adaptation requires both generation of novel phenotypic variation and retention of a locally beneficial subset of this variation. Such retention can be facilitated by genetic assimilation, the accumulation of genetic and molecular mechanisms that stabilize induced phenotypes and assume progressively greater control over their reliable production. A particularly strong inference into genetic assimilation as an evolutionary process requires a system where it is possible to directly evaluate the extent to which an induced phenotype is progressively incorporated into preexisting developmental pathways. Evolution of diet-dependent pigmentation in birds-where external carotenoids are coopted into internal metabolism to a variable degree before being integrated with a feather's developmental processes-provides such an opportunity. Here we combine a metabolic network view of carotenoid evolution with detailed empirical study of feather modifications to show that the effect of physical properties of carotenoids on feather structure depends on their metabolic modification, their environmental recurrence, and biochemical redundancy, as predicted by the genetic assimilation hypothesis. Metabolized carotenoids caused less stochastic variation in feather structure and were more closely integrated with feather growth than were dietary carotenoids of the same molecular weight. These patterns were driven by the recurrence of organism-carotenoid associations: commonly used dietary carotenoids and biochemically redundant derived carotenoids caused less stochastic variation in feather structure than did rarely used or biochemically unique compounds. We discuss implications of genetic assimilation processes for the evolutionary diversification of diet-dependent animal coloration.

Novelty response and 50 kHz ultrasonic vocalizations: Differential prediction of locomotor and affective response to amphetamine in Sprague-Dawley rats.

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Garcia, Erik J; Cain, Mary E

2016-02-01

Novelty and sensation seeking (NSS) predisposes humans and rats to experiment with psychostimulants. In animal models, different tests of NSS predict different phases of drug dependence. Ultrasonic vocalizations (USVs) are evoked by psychomotor stimulants and measure the affective/motivation response to stimuli, yet the role NSS has on USVs in response to amphetamine is not determined. The aim of the present study was to determine if individual differences in NSS and USVs can predict locomotor and USV response to amphetamine (0.0, 0.3, and 1.0 mg/kg) after acute and chronic exposure. Thirty male rats were tested for their response to novelty (IEN), choice to engage in novelty (NPP), and heterospecific play (H-USV). Rats were administered non-contingent amphetamine or saline for seven exposures, and USVs and locomotor activity were measured. After a 14-day rest, rats were administered a challenge dose of amphetamine. Regression analyses indicated that amphetamine dose-dependently increased locomotor activity and the NPP test negatively predicted treatment-induced locomotor activity. The H-USV test predicted treatment-induced frequency-modulated (FM) USVs, but the strength of prediction depended on IEN response. Results provide evidence that locomotor activity and FM USVs induced by amphetamine represent different behavioral responses. The prediction of amphetamine-induced FM USVs by the H-USV screen was changed by the novelty response, indicating that the affective value of amphetamine-measured by FM USVs-depends on novelty response. This provides evidence that higher novelty responders may develop a tolerance faster and may escalate intake faster.

Exploring the Experience of Novelty When Viewing Creative Adverts: An ERP Study

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Shujin Zhou

2018-04-01

Full Text Available The electrophysiological correlates of experiencing novelty in creative advertising were studied in 28 healthy subjects using event-related potentials. Participants viewed images that were difficult to interpret until a description was presented providing either a creative description (CD featuring an unexpected description of the image based on the original advertisement, or a normal description (ND, which was a literal description of the image (and served as a baseline condition. Participants evaluated the level of creativity of the description. The results showed that the N2 amplitude was higher for CDs than for NDs across middle and right scalp regions between 240 and 270 ms, most likely reflecting conflict detection. Moreover, CDs demonstrated greater N400 than NDs in a time window between 380 and 500 ms, it is argued that this reflects semantic integration. The present study investigates the electrophysiological correlates of experiencing novelty in advertising with ecologically valid stimuli. This substantially extends the findings of earlier laboratory studies with more artificial stimuli.

Is the evolutionary theory still useful?: A review with examples ¿Es todavía útil la teoría evolutiva?: Una revisión con ejemplos

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ROBERTO F NESPOLO

2010-12-01

Full Text Available Evolutionary biology is experiencing an exceptional process of revisión and outreach because of the 200-anniversary if the birth of Charles Darwin. As a consequence, the study of organic evolution and also its teaching are being discussed at several levels, by evolutionary biologists, biologists and scholars outside evolutionary biology and by the general public. In this scenario, a didactic explanation of how biologists address evolutionary research in real populations seems to be useful. Using actual research examples, here I tried to outline how the classic theory (termed here as the "basic scheme" is useful to answer relevant questions in biology and how a less dogmatic paradigm (or a more versatile one would be needed when dealing with the most recent and extravagant cases of gene, genotype, phenotype and environment interactions. Specifically, I used three in-extenso examples of research driven by hypothesis-testing: (1 the changes in genetic architecture induced by sexuality in a cyclically parthenogenetic insect; (2 the test of the energetic definition of fitness through phenotypic selection studies; and (3 the assessment of the underlying causes of character displacement in Darwin finches. In the former two cases, it is argued that the basic scheme is useful and sufficient for testing relevant evolutionary hypotheses. In the third case, it is argued that something else is needed to explain the observed genetic variation that Geospiza species exhibit in Daphne major island (Galapagos. Finally, I outline some "extravagant" cases biological entities interacting, such as horizontal gene transfer, epigenetic inheritance, adaptive anticipatory conditioning, evolutionary capacitance and niche construction. This "post-modern" biology has been seriously proposed and demonstrated to be widespread in nature, which would justify an extended evolutionary synthesis.La biología evolutiva está experimentando un inédito proceso de revisión y difusi

Evolutionary trade-offs in kidney injury and repair.

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Lei, Yutian; Anders, Hans-Joachim

2017-11-01

Evolutionary medicine has proven helpful to understand the origin of human disease, e.g. in identifying causal roles of recent environmental changes impacting on human physiology (environment-phenotype mismatch). In contrast, diseases affecting only a limited number of members of a species often originate from evolutionary trade-offs for usually physiologic adaptations assuring reproductive success in the context of extrinsic threats. For example, the G1 and G2 variants of the APOL1 gene supporting control of Trypanosoma infection come with the trade-off that they promote the progression of kidney disease. In this review we extend the concept of evolutionary nephrology by discussing how the physiologic adaptations (danger responses) to tissue injury create evolutionary trade-offs that drive histopathological changes underlying acute and chronic kidney diseases. The evolution of multicellular organisms positively selected a number of danger response programs for their overwhelming benefits in assuring survival such as clotting, inflammation, epithelial healing and mesenchymal healing, i.e. fibrosis and sclerosis. Upon kidney injury these danger programs often present as pathomechanisms driving persistent nephron loss and renal failure. We explore how classic kidney disease entities involve insufficient or overshooting activation of these danger response programs for which the underlying genetic basis remains largely to be defined. Dissecting the causative and hierarchical relationships between danger programs should help to identify molecular targets to control kidney injury and to improve disease outcomes.

Patterns of coordinated cortical remodeling during adolescence and their associations with functional specialization and evolutionary expansion.

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Sotiras, Aristeidis; Toledo, Jon B; Gur, Raquel E; Gur, Ruben C; Satterthwaite, Theodore D; Davatzikos, Christos

2017-03-28

During adolescence, the human cortex undergoes substantial remodeling to support a rapid expansion of behavioral repertoire. Accurately quantifying these changes is a prerequisite for understanding normal brain development, as well as the neuropsychiatric disorders that emerge in this vulnerable period. Past accounts have demonstrated substantial regional heterogeneity in patterns of brain development, but frequently have been limited by small samples and analytics that do not evaluate complex multivariate imaging patterns. Capitalizing on recent advances in multivariate analysis methods, we used nonnegative matrix factorization (NMF) to uncover coordinated patterns of cortical development in a sample of 934 youths ages 8-20, who completed structural neuroimaging as part of the Philadelphia Neurodevelopmental Cohort. Patterns of structural covariance (PSCs) derived by NMF were highly reproducible over a range of resolutions, and differed markedly from common gyral-based structural atlases. Moreover, PSCs were largely symmetric and showed correspondence to specific large-scale functional networks. The level of correspondence was ordered according to their functional role and position in the evolutionary hierarchy, being high in lower-order visual and somatomotor networks and diminishing in higher-order association cortex. Furthermore, PSCs showed divergent developmental associations, with PSCs in higher-order association cortex networks showing greater changes with age than primary somatomotor and visual networks. Critically, such developmental changes within PSCs were significantly associated with the degree of evolutionary cortical expansion. Together, our findings delineate a set of structural brain networks that undergo coordinated cortical thinning during adolescence, which is in part governed by evolutionary novelty and functional specialization.

Reconstructing the Evolutionary History of Paralogous APETALA1/FRUITFULL-Like Genes in Grasses (Poaceae)

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Preston, Jill C.; Kellogg, Elizabeth A.

2006-01-01

Gene duplication is an important mechanism for the generation of evolutionary novelty. Paralogous genes that are not silenced may evolve new functions (neofunctionalization) that will alter the developmental outcome of preexisting genetic pathways, partition ancestral functions (subfunctionalization) into divergent developmental modules, or function redundantly. Functional divergence can occur by changes in the spatio-temporal patterns of gene expression and/or by changes in the activities of their protein products. We reconstructed the evolutionary history of two paralogous monocot MADS-box transcription factors, FUL1 and FUL2, and determined the evolution of sequence and gene expression in grass AP1/FUL-like genes. Monocot AP1/FUL-like genes duplicated at the base of Poaceae and codon substitutions occurred under relaxed selection mostly along the branch leading to FUL2. Following the duplication, FUL1 was apparently lost from early diverging taxa, a pattern consistent with major changes in grass floral morphology. Overlapping gene expression patterns in leaves and spikelets indicate that FUL1 and FUL2 probably share some redundant functions, but that FUL2 may have become temporally restricted under partial subfunctionalization to particular stages of floret development. These data have allowed us to reconstruct the history of AP1/FUL-like genes in Poaceae and to hypothesize a role for this gene duplication in the evolution of the grass spikelet. PMID:16816429

Embodied artificial evolution: Artificial evolutionary systems in the 21st Century.

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Eiben, A E; Kernbach, S; Haasdijk, Evert

2012-12-01

Evolution is one of the major omnipresent powers in the universe that has been studied for about two centuries. Recent scientific and technical developments make it possible to make the transition from passively understanding to actively using evolutionary processes. Today this is possible in Evolutionary Computing, where human experimenters can design and manipulate all components of evolutionary processes in digital spaces. We argue that in the near future it will be possible to implement artificial evolutionary processes outside such imaginary spaces and make them physically embodied. In other words, we envision the "Evolution of Things", rather than just the evolution of digital objects, leading to a new field of Embodied Artificial Evolution (EAE). The main objective of this paper is to present a unifying vision in order to aid the development of this high potential research area. To this end, we introduce the notion of EAE, discuss a few examples and applications, and elaborate on the expected benefits as well as the grand challenges this developing field will have to address.

Nucleus accumbens cocaine-amphetamine regulated transcript mediates food intake during novelty conflict

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Burghardt, PR; Krolewski, DM; Dykhuis, KE; Ching, J; Pinawin, AM; Britton, SL; Koch, LG; Watson, SJ; Akil, H.

2016-01-01

Obesity is a persistent and pervasive problem, particularly in industrialized nations. It has come to be appreciated that the metabolic health of an individual can influence brain function and subsequent behavioral patterns. To examine the relationship between metabolic phenotype and central systems that regulate behavior, we tested rats with divergent metabolic phenotypes (Low Capacity Runner: LCR vs. High Capacity Runner: HCR) for behavioral responses to the conflict between hunger and environmental novelty using the novelty suppressed feeding (NSF) paradigm. Additionally, we measured expression of mRNA, for peptides involved in energy management, in response to fasting. Following a 24-h fast, LCR rats showed lower latencies to begin eating in a novel environment compared to HCR rats. A 48-h fast equilibrated the latency to begin eating in the novel environment. A 24-h fast differentially affected expression of cocaine-amphetamine regulated transcript (CART) mRNA in the nucleus accumbens (NAc), where 24-h of fasting reduced CART mRNA in LCR rats. Bilateral microinjections of CART 55–102 peptide into the NAc increased the latency to begin eating in the NSF paradigm following a 24-h fast in LCR rats. These results indicate that metabolic phenotype influences how animals cope with the conflict between hunger and novelty, and that these differences are at least partially mediated by CART signaling in the NAc. For individuals with poor metabolic health who have to navigate food-rich and stressful environments, changes in central systems that mediate conflicting drives may feed into the rates of obesity and exacerbate the difficulty individuals have in maintaining weight loss. PMID:26926827

phyloXML: XML for evolutionary biology and comparative genomics.

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Han, Mira V; Zmasek, Christian M

2009-10-27

Evolutionary trees are central to a wide range of biological studies. In many of these studies, tree nodes and branches need to be associated (or annotated) with various attributes. For example, in studies concerned with organismal relationships, tree nodes are associated with taxonomic names, whereas tree branches have lengths and oftentimes support values. Gene trees used in comparative genomics or phylogenomics are usually annotated with taxonomic information, genome-related data, such as gene names and functional annotations, as well as events such as gene duplications, speciations, or exon shufflings, combined with information related to the evolutionary tree itself. The data standards currently used for evolutionary trees have limited capacities to incorporate such annotations of different data types. We developed a XML language, named phyloXML, for describing evolutionary trees, as well as various associated data items. PhyloXML provides elements for commonly used items, such as branch lengths, support values, taxonomic names, and gene names and identifiers. By using "property" elements, phyloXML can be adapted to novel and unforeseen use cases. We also developed various software tools for reading, writing, conversion, and visualization of phyloXML formatted data. PhyloXML is an XML language defined by a complete schema in XSD that allows storing and exchanging the structures of evolutionary trees as well as associated data. More information about phyloXML itself, the XSD schema, as well as tools implementing and supporting phyloXML, is available at http://www.phyloxml.org.

Rikkunshito, a Japanese Kampo Medicine, Ameliorates Decreased Feeding Behavior via Ghrelin and Serotonin 2B Receptor Signaling in a Novelty Stress Murine Model

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Chihiro Yamada

2013-01-01

Full Text Available We investigated the effects of rikkunshito (RKT, a ghrelin signal enhancer, on the decrease in food intake after exposure to novelty stress in mice. RKT administration (500 mg/kg, per os improved the decrease in 6 h cumulative food intake. In control mice, the plasma acylated ghrelin levels significantly increased by 24 h fasting. In contrast, the acylated ghrelin levels did not increase by fasting in mice exposed to the novelty stress. RKT administration to the novelty stress mice showed a significant increase in the acylated ghrelin levels compared with that in the distilled-water-treated control mice. Food intake after administering serotonin 2B (5-HT2B receptor antagonists was evaluated to clarify the role of 5-HT2B receptor activation in the decrease in feeding behavior after novelty stress. SB215505 and SB204741, 5-HT2B receptor antagonists, significantly improved the decrease in food intake after exposure to novelty stress. A component of RKT, isoliquiritigenin, prevented the decrease in 6 h cumulative food intake. Isoliquiritigenin showed 5-HT2B receptor antagonistic activity in vitro. In conclusion, the results suggested that RKT improves the decrease in food intake after novelty stress probably via 5-HT2B receptor antagonism of isoliquiritigenin contained in RKT.

Evolutionary thinking

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Hunt, Tam

2014-01-01

Evolution as an idea has a lengthy history, even though the idea of evolution is generally associated with Darwin today. Rebecca Stott provides an engaging and thoughtful overview of this history of evolutionary thinking in her 2013 book, Darwin's Ghosts: The Secret History of Evolution. Since Darwin, the debate over evolution—both how it takes place and, in a long war of words with religiously-oriented thinkers, whether it takes place—has been sustained and heated. A growing share of this debate is now devoted to examining how evolutionary thinking affects areas outside of biology. How do our lives change when we recognize that all is in flux? What can we learn about life more generally if we study change instead of stasis? Carter Phipps’ book, Evolutionaries: Unlocking the Spiritual and Cultural Potential of Science's Greatest Idea, delves deep into this relatively new development. Phipps generally takes as a given the validity of the Modern Synthesis of evolutionary biology. His story takes us into, as the subtitle suggests, the spiritual and cultural implications of evolutionary thinking. Can religion and evolution be reconciled? Can evolutionary thinking lead to a new type of spirituality? Is our culture already being changed in ways that we don't realize by evolutionary thinking? These are all important questions and Phipps book is a great introduction to this discussion. Phipps is an author, journalist, and contributor to the emerging “integral” or “evolutionary” cultural movement that combines the insights of Integral Philosophy, evolutionary science, developmental psychology, and the social sciences. He has served as the Executive Editor of EnlightenNext magazine (no longer published) and more recently is the co-founder of the Institute for Cultural Evolution, a public policy think tank addressing the cultural roots of America's political challenges. What follows is an email interview with Phipps. PMID:26478766

An evolutionary perspective on drug discovery in the plant genus Euphorbia L. (Euphorbiaceae)

DEFF Research Database (Denmark)

Ernst, Madeleine

herbivory and physical stresses or to attract pollinators. Consequently, specializedmetabolites, as well as plants used in traditional medicine, are not randomly distributed across phylogenetictrees. Evolutionary approaches to plant-based drug discovery suggest that this informationcan be used to guide...... healthcarethreats, urge for systematic and time-efficient approaches in finding new drug candidates. Manydrugs are derived from plant specialized metabolites, chemical compounds, which are synthesizedby the plants in response to evolutionary adaptation to environmental and ecological factors, for example,to combat...... evolution and diversification. Also, Euphorbia species producean often chemically highly diverse latex exhibiting an exceptional number of biological activities withpharmaceutical interest. In this PhD project, the genus Euphorbia was chosen as a model group forstudying evolutionary approaches to plant...

An open future for ecological and evolutionary data?

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Kenall, Amye; Harold, Simon; Foote, Christopher

2014-04-02

As part of BioMed Central's open science mission, we are pleased to announce that two of our journals have integrated with the open data repository Dryad. Authors submitting their research to either BMC Ecology or BMC Evolutionary Biology will now have the opportunity to deposit their data directly into the Dryad archive and will receive a permanent, citable link to their dataset. Although this does not affect any of our current data deposition policies at these journals, we hope to encourage a more widespread adoption of open data sharing in the fields of ecology and evolutionary biology by facilitating this process for our authors. We also take this opportunity to discuss some of the wider issues that may concern researchers when making their data openly available. Although we offer a number of positive examples from different fields of biology, we also recognise that reticence to data sharing still exists, and that change must be driven from within research communities in order to create future science that is fit for purpose in the digital age. This editorial was published jointly in both BMC Ecology and BMC Evolutionary Biology.

Novelty detection methods for online health monitoring and post data analysis of turbopumps

International Nuclear Information System (INIS)

Lei Hu; Niaoqing, Hu; Xinpeng, Zhang; Fengshou, Gu; Ming, Gao

2013-01-01

As novelty detection works when only normal data are available, it is of considerable promise for health monitoring in cases lacking fault samples and prior knowledge. We present two novelty detection methods for health monitoring of turbopumps in large-scale liquid propellant rocket engines. The first method is the adaptive Gaussian threshold model. This method is designed to monitor the vibration of the turbopumps online because it has minimal computational complexity and is easy for implementation in real time. The second method is the one-class support vector machine (OCSVM) which is developed for post analysis of historical vibration signals. Via post analysis the method not only confirms the online monitoring results but also provides diagnostic results so that faults from sensors are separated from those actually from the turbopumps. Both of these two methods are validated to be efficient for health monitoring of the turbopumps.

Polycose taste pre-exposure fails to influence behavioral and neural indices of taste novelty.

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Barot, Sabiha K; Bernstein, Ilene L

2005-12-01

Taste novelty can strongly modulate the speed and efficacy of taste aversion learning. Novel sweet tastes enhance c-Fos-like immunoreactivity (FLI) in the central amygdala and insular cortex. The present studies examined whether this neural correlate of novelty extends to different taste types by measuring FLI signals after exposure to novel and familiar polysaccharide (Polycose) and salt (NaCl) tastes. Novel Polycose not only failed to elevate FLI expression in central amygdala and insular cortex, but also failed to induce stronger taste aversion learning than familiar Polycose. Novel NaCl, on the other hand, showed patterns of FLI activation and aversion learning similar to that of novel sweet tastes. Possible reasons for the resistance of Polycose to typical pre-exposure effects are discussed. Copyright (c) 2006 APA, all rights reserved.

The role of novelty detection in food memory.

Science.gov (United States)

Morin-Audebrand, Léri; Mojet, Jos; Chabanet, Claire; Issanchou, Sylvie; Møller, Per; Köster, Ep; Sulmont-Rossé, Claire

2012-01-01

Memory plays a central role in food choice. Recent studies focusing on food memory in everyday eating and drinking behaviour used a paradigm based on incidental learning of target foods and unexpected memory testing, demanding recognition of the target among distractors, which deviate slightly from the target. Results question the traditional view of memory as reactivation of previous experiences. Comparison of data from several experiments shows that in incidentally learned memory, distractors are rejected, while original targets are not recognised better than by chance guessing. Food memory is tuned at detecting novelty and change, rather than at recognising a previously encountered food. Copyright © 2011. Published by Elsevier B.V.

Evolutionary Stable Strategy

Indian Academy of Sciences (India)

Home; Journals; Resonance – Journal of Science Education; Volume 21; Issue 9. Evolutionary Stable Strategy: Application of Nash Equilibrium in Biology. General Article Volume 21 Issue 9 September 2016 pp 803- ... Keywords. Evolutionary game theory, evolutionary stable state, conflict, cooperation, biological games.

Role of stress system disturbance and enhanced novelty response in spatial learning of NCAM-deficient mice.

Science.gov (United States)

Brandewiede, Joerg; Jakovcevski, Mira; Stork, Oliver; Schachner, Melitta

2013-11-01

The neural cell adhesion molecule (NCAM) plays a crucial role in stress-related brain function, emotional behavior and memory formation. In this study, we investigated the functions of the glucocorticoid and serotonergic systems in mice constitutively deficient for NCAM (NCAM-/- mice). Our data provide evidence for a hyperfunction of the hypothalamic-pituitary-adrenal axis, with enlarged adrenal glands and increased stress-induced corticosterone release, but reduced hippocampal glucocorticoid receptor expression in NCAM-/- mice when compared to NCAM+/+ mice. We also obtained evidence for a hypofunction of 5-HT1A autoreceptors as indicated by increased 8-0H-DPAT-induced hypothermia. These findings suggest a disturbance of both humoral and neural stress systems in NCAM-/- mice. Accordingly, we not only confirmed previously observed hyperarousal of NCAM-/- mice in various anxiety tests, but also observed an increased response to novelty exposure in these animals. Spatial learning deficits of the NCAM-/- mice in a Morris Water maze persisted, even when mice were pretrained to prevent effects of novelty or stress. We suggest that NCAM-mediated processes are involved in both novelty/stress-related emotional behavior and in cognitive function during spatial learning.

Social competitiveness and plasticity of neuroendocrine function in old age: influence of neonatal novelty exposure and maternal care reliability.

Directory of Open Access Journals (Sweden)

Katherine G Akers

Full Text Available Early experience is known to have a profound impact on brain and behavioral function later in life. Relatively few studies, however, have examined whether the effects of early experience remain detectable in the aging animal. Here, we examined the effects of neonatal novelty exposure, an early stimulation procedure, on late senescent rats' ability to win in social competition. During the first 3 weeks of life, half of each litter received daily 3-min exposures to a novel environment while the other half stayed in the home cage. At 24 months of age, pairs of rats competed against each other for exclusive access to chocolate rewards. We found that novelty-exposed rats won more rewards than home-staying rats, indicating that early experience exerts a life-long effect on this aspect of social dominance. Furthermore, novelty-exposed but not home-staying rats exhibited habituation of corticosterone release across repeated days of social competition testing, suggesting that early experience permanently enhances plasticity of the stress response system. Finally, we report a surprising finding that across individual rat families, greater effects of neonatal novelty exposure on stress response plasticity were found among families whose dams provided more reliable, instead of a greater total quantity of, maternal care.

A Computable Plug-In Estimator of Minimum Volume Sets for Novelty Detection

KAUST Repository

Park, Chiwoo; Huang, Jianhua Z.; Ding, Yu

2010-01-01

A minimum volume set of a probability density is a region of minimum size among the regions covering a given probability mass of the density. Effective methods for finding the minimum volume sets are very useful for detecting failures or anomalies in commercial and security applications-a problem known as novelty detection. One theoretical approach of estimating the minimum volume set is to use a density level set where a kernel density estimator is plugged into the optimization problem that yields the appropriate level. Such a plug-in estimator is not of practical use because solving the corresponding minimization problem is usually intractable. A modified plug-in estimator was proposed by Hyndman in 1996 to overcome the computation difficulty of the theoretical approach but is not well studied in the literature. In this paper, we provide theoretical support to this estimator by showing its asymptotic consistency. We also show that this estimator is very competitive to other existing novelty detection methods through an extensive empirical study. ©2010 INFORMS.

A Computable Plug-In Estimator of Minimum Volume Sets for Novelty Detection

KAUST Repository

Park, Chiwoo

2010-10-01

A minimum volume set of a probability density is a region of minimum size among the regions covering a given probability mass of the density. Effective methods for finding the minimum volume sets are very useful for detecting failures or anomalies in commercial and security applications-a problem known as novelty detection. One theoretical approach of estimating the minimum volume set is to use a density level set where a kernel density estimator is plugged into the optimization problem that yields the appropriate level. Such a plug-in estimator is not of practical use because solving the corresponding minimization problem is usually intractable. A modified plug-in estimator was proposed by Hyndman in 1996 to overcome the computation difficulty of the theoretical approach but is not well studied in the literature. In this paper, we provide theoretical support to this estimator by showing its asymptotic consistency. We also show that this estimator is very competitive to other existing novelty detection methods through an extensive empirical study. ©2010 INFORMS.

Evolutionary Science as a Method to Facilitate Higher Level Thinking and Reasoning in Medical Training.

Science.gov (United States)

Graves, Joseph L; Reiber, Chris; Thanukos, Anna; Hurtado, Magdalena; Wolpaw, Terry

2016-10-15

Evolutionary science is indispensable for understanding biological processes. Effective medical treatment must be anchored in sound biology. However, currently the insights available from evolutionary science are not adequately incorporated in either pre-medical or medical school curricula. To illuminate how evolution may be helpful in these areas, examples in which the insights of evolutionary science are already improving medical treatment and ways in which evolutionary reasoning can be practiced in the context of medicine are provided. In order to facilitate the learning of evolutionary principles, concepts derived from evolutionary science that medical students and professionals should understand are outlined. These concepts are designed to be authoritative and at the same time easily accessible for anyone with the general biological knowledge of a first-year medical student. Thus we conclude that medical practice informed by evolutionary principles will be more effective and lead to better patient outcomes.Furthermore, it is argued that evolutionary medicine complements general medical training because it provides an additional means by which medical students can practice the critical thinking skills that will be important in their future practice. We argue that core concepts from evolutionary science have the potential to improve critical thinking and facilitate more effective learning in medical training. © The Author(s) 2016. Published by Oxford University Press on behalf of the Foundation for Evolution, Medicine, and Public Health.

How schema and novelty augment memory formation.

Science.gov (United States)

van Kesteren, Marlieke T R; Ruiter, Dirk J; Fernández, Guillén; Henson, Richard N

2012-04-01

Information that is congruent with existing knowledge (a schema) is usually better remembered than less congruent information. Only recently, however, has the role of schemas in memory been studied from a systems neuroscience perspective. Moreover, incongruent (novel) information is also sometimes better remembered. Here, we review lesion and neuroimaging findings in animals and humans that relate to this apparent paradoxical relationship between schema and novelty. In addition, we sketch a framework relating key brain regions in medial temporal lobe (MTL) and medial prefrontal cortex (mPFC) during encoding, consolidation and retrieval of information as a function of its congruency with existing information represented in neocortex. An important aspect of this framework is the efficiency of learning enabled by congruency-dependent MTL-mPFC interactions. Copyright © 2012 Elsevier Ltd. All rights reserved.

Fronto-limbic novelty processing in acute psychosis: disrupted relationship with memory performance and potential implications for delusions

Directory of Open Access Journals (Sweden)

Björn H Schott

2015-06-01

Full Text Available Recent concepts have highlighted the role of the hippocampus and adjacent medial temporal lobe (MTL in positive symptoms like delusions in schizophrenia. In healthy individuals, the MTL is critically involved in the detection and encoding of novel information. Here, we aimed to investigate whether dysfunctional novelty processing by the MTL might constitute a potential neural mechanism contributing to the pathophysiology of delusions, using functional magnetic resonance imaging (fMRI in 16 unmedicated patients with paranoid schizophrenia and 20 age-matched healthy controls. All patients experienced positive symptoms at time of participation. Participants performed a visual target detection task with complex scene stimuli in which novel and familiar rare stimuli were presented randomly intermixed with a standard and a target picture. Presentation of novel relative to familiar images was associated with hippocampal activation in both patients and healthy controls, but only healthy controls showed a positive relationship between novelty-related hippocampal activation and recognition memory performance after 24 hours. Patients, but not controls, showed a robust neural response in the orbitofrontal cortex (OFC during presentation of novel stimuli. Functional connectivity analysis in the patients further revealed a novelty-related increase of functional connectivity of both the hippocampus and the OFC with the rostral anterior cingulate cortex (rACC and the ventral striatum. Notably, delusions correlated positively with the difference of the functional connectivity of the hippocampus versus the OFC with the rACC. Taken together, our results suggest that alterations of fronto-limbic novelty processing may contribute to the pathophysiology of delusions in patients with acute psychosis.

Optimality and stability of symmetric evolutionary games with applications in genetic selection.

Science.gov (United States)

Huang, Yuanyuan; Hao, Yiping; Wang, Min; Zhou, Wen; Wu, Zhijun

2015-06-01

Symmetric evolutionary games, i.e., evolutionary games with symmetric fitness matrices, have important applications in population genetics, where they can be used to model for example the selection and evolution of the genotypes of a given population. In this paper, we review the theory for obtaining optimal and stable strategies for symmetric evolutionary games, and provide some new proofs and computational methods. In particular, we review the relationship between the symmetric evolutionary game and the generalized knapsack problem, and discuss the first and second order necessary and sufficient conditions that can be derived from this relationship for testing the optimality and stability of the strategies. Some of the conditions are given in different forms from those in previous work and can be verified more efficiently. We also derive more efficient computational methods for the evaluation of the conditions than conventional approaches. We demonstrate how these conditions can be applied to justifying the strategies and their stabilities for a special class of genetic selection games including some in the study of genetic disorders.

Temporal stability of novelty exploration in mice exposed to different open field tests.

Science.gov (United States)

Kalueff, Allan V; Keisala, Tiina; Minasyan, Anna; Kuuslahti, Marianne; Tuohimaa, Pentti

2006-03-01

We investigated behavioural activity and temporal distribution (patterning) of mouse exploration in different open field (OF) arenas. Mice of 129S1 (S1) strain were subjected in parallel to three different OF arenas (Experiment 1), two different OF arenas in two trials (Experiment 2) or two trials of the same OF test (Experiment 3). Overall, mice demonstrated a high degree of similarity in the temporal profile of novelty-induced horizontal and vertical exploration (regardless of the size, colour and shape of the OF), which remained stable in subsequent OF exposures. In Experiments 4 and 5, we tested F1 hybrid mice (BALB/c-S1; NMRI-S1), and Vitamin D receptor knockout mice (generated on S1 genetic background), again showing strikingly similar temporal patterns of their OF exploration, despite marked behavioural strain differences in anxiety and activity. These results suggest that mice are characterised by stability of temporal organization of their exploration in different OF novelty situations.

Novelty processing and memory formation in Parkinson's disease.

Science.gov (United States)

Schomaker, J; Berendse, H W; Foncke, E M J; van der Werf, Y D; van den Heuvel, O A; Theeuwes, J; Meeter, M

2014-09-01

Parkinson's disease (PD) is characterized by a degeneration of nigrostriatal dopaminergic cells, resulting in dopamine depletion. This depletion is counteracted through dopamine replacement therapy (DRT). Dopamine has been suggested to affect novelty processing and memory, which suggests that these processes are also implicated in PD and that DRT could affect them. To investigate word learning and novelty processing in patients with PD as indexed by the P2 and P3 event-related potential components, and the role of DRT in these processes. 21 patients with PD and 21 matched healthy controls were included. Patients with PD were tested on and off DRT in two sessions in a counterbalanced design, and healthy controls were tested twice without intervention. Electroencephalogram (EEG) was measured while participants performed a word learning Von Restorff task. Healthy controls showed the typical Von Restorff effect, with better memory for words that were presented in novel fonts, than for words presented in standard font. Surprisingly, this effect was reversed in the patients with PD. In line with the behavioral findings, the P3 was larger for novel than for standard font words in healthy controls, but not in patients with PD. For both groups the P2 and P3 event-related components were larger for recalled versus forgotten words. DRT did not affect these processes. Learning of novel information is compromised in patients with PD. Likewise, the P2 and P3 components that predict successful memory encoding are reduced in PD patients. This was true both on and off DRT, suggesting that these findings reflect abnormalities in learning and memory in PD that are not resolved by dopaminergic medication. Copyright © 2014 Elsevier Ltd. All rights reserved.

EvoluCode: Evolutionary Barcodes as a Unifying Framework for Multilevel Evolutionary Data.

Science.gov (United States)

Linard, Benjamin; Nguyen, Ngoc Hoan; Prosdocimi, Francisco; Poch, Olivier; Thompson, Julie D

2012-01-01

Evolutionary systems biology aims to uncover the general trends and principles governing the evolution of biological networks. An essential part of this process is the reconstruction and analysis of the evolutionary histories of these complex, dynamic networks. Unfortunately, the methodologies for representing and exploiting such complex evolutionary histories in large scale studies are currently limited. Here, we propose a new formalism, called EvoluCode (Evolutionary barCode), which allows the integration of different evolutionary parameters (eg, sequence conservation, orthology, synteny …) in a unifying format and facilitates the multilevel analysis and visualization of complex evolutionary histories at the genome scale. The advantages of the approach are demonstrated by constructing barcodes representing the evolution of the complete human proteome. Two large-scale studies are then described: (i) the mapping and visualization of the barcodes on the human chromosomes and (ii) automatic clustering of the barcodes to highlight protein subsets sharing similar evolutionary histories and their functional analysis. The methodologies developed here open the way to the efficient application of other data mining and knowledge extraction techniques in evolutionary systems biology studies. A database containing all EvoluCode data is available at: http://lbgi.igbmc.fr/barcodes.

Historical contingency and ecological determinism interact to prime speciation in sticklebacks, Gasterosteus.

Science.gov (United States)

Taylor, E B; McPhail, J D

2000-01-01

Historical contingency and determinism are often cast as opposing paradigms under which evolutionary diversification operates. It may be, however, that both factors act together to promote evolutionary divergence, although there are few examples of such interaction in nature. We tested phylogenetic predictions of an explicit historical model of divergence (double invasions of freshwater by marine ancestors) in sympatric species of three-spined sticklebacks (Gasterosteus aculeatus) where determinism has been implicated as an important factor driving evolutionary novelty. Microsatellite DNA variation at six loci revealed relatively low genetic variation in freshwater populations, supporting the hypothesis that they were derived by colonization of freshwater by more diverse marine ancestors. Phylogenetic and genetic distance analyses suggested that pairs of sympatric species have evolved multiple times, further implicating determinism as a factor in speciation. Our data also supported predictions based on the hypothesis that the evolution of sympatric species was contingent upon 'double invasions' of postglacial lakes by ancestral marine sticklebacks. Sympatric sticklebacks, therefore, provide an example of adaptive radiation by determinism contingent upon historical conditions promoting unique ecological interactions, and illustrate how contingency and determinism may interact to generate geographical variation in species diversity PMID:11133026

Short- and long-lasting consequences of novelty, deviance, and surprise on brain and cognition

NARCIS (Netherlands)

Schomaker, J.; Meeter, M.

2015-01-01

When one encounters a novel stimulus this sets off a cascade of brain responses, activating several neuromodulatory systems. As a consequence novelty has a wide range of effects on cognition; improving perception and action, increasing motivation, eliciting exploratory behavior, and promoting

Using large-scale public health data to explore the evolutionary biology of human pregnancy and child bearing

DEFF Research Database (Denmark)

Hollegaard, Birgitte

. Consequently, research has increasingly focused on the underlying causes of disease, shaped by human evolution. Evolutionary medicine is a relatively new field, specifically bridging the gap between conventional medicine and evolutionary biology: Instead of asking how we get sick, we can apply evolutionary...... explanations for this phenomenon. This thesis demonstrates how taking an evolutionary perspective can help us to better understand important aspects of health and medicine that remain opaque, using the specific example of pregnancy-related conditions.......Medicine has made a giant leap forward over the last century when it comes to the treatment of human disease, but even the most cutting edge 21st century medicine cannot prevent new diseases arising, nor those thought to be extinct developing resistance to pharmaceuticals and returning...

An evolutionary cosmology for scientists--and the modern world in general.

Science.gov (United States)

Charlton, Bruce G

2007-01-01

I believe that people will not feel comfortable and positive about the contemporary world until we can endorse and believe an evolutionary cosmology which is appropriate to modern conditions. A cosmology is a mythical account of the universe as it presents itself to the human mind; it needs to be poetic, symbolic, inspiring of a sense of awe and mystery. Furthermore, a complete cosmology should include the three levels of macro-, meso- and micro-cosm, in order to understand the nature of the universe, human society, and the individual's relation to them. Traditional cosmologies described an eternal underlying structure to ultimate reality--a static ideal state towards which the world ought to gravitate. However, modern life is characterized by rapid growth, novelty, destruction and fluidity of all kinds of structures, a feature which traditional static cosmologies interpret negatively and pessimistically. A modern cosmology therefore needs to be focused on underlying dynamic process instead of structure and stasis. Biologists are better placed than many to appreciate a cosmology based on evolutionary change; because this is the mainstream understanding of adaptation and diversity in the natural world. The same dynamic, neophiliac and open-ended process of 'creative destruction' can be seen at work in science, economics, and modern spirituality. But a modern cosmology will only be experienced as both deep and spontaneous when it takes the form of a mythic account that is first encountered and assimilated during childhood. Since myths arise as a consequence of human creativity; there is a vital future mythogenic role for artists in the realm of ideas, images and stories: people such as mystics, poets and philosophers--including, I hope and expect, creatively inspired scientists.

Evolutionary Ship Track Planning within Traffic Separation Schemes – Evaluation of Individuals

Directory of Open Access Journals (Sweden)

Rafal Szlapczynski

2013-06-01

Full Text Available The paper presents an extended version of the author’s Evolutionary Sets of Safe Ship Trajectories method. The method plans safe tracks of all ships involved in an encounter including speed reduction maneuvers, if necessary, and taking into account Rule 10 of COLREGS, which specifies ships’ behavior within Traffic Separation Schemes governed by IMO. The paper focuses on the evaluation phase of the evolutionary process and shows how fitness function is designed to compare various possible tracks as well as to assess the quality of a final solution. The impact of the fitness function on the method’s results is illustrated by examples.

Expanding the eco-evolutionary context of herbicide resistance research.

Science.gov (United States)

Neve, Paul; Busi, Roberto; Renton, Michael; Vila-Aiub, Martin M

2014-09-01

The potential for human-driven evolution in economically and environmentally important organisms in medicine, agriculture and conservation management is now widely recognised. The evolution of herbicide resistance in weeds is a classic example of rapid adaptation in the face of human-mediated selection. Management strategies that aim to slow or prevent the evolution of herbicide resistance must be informed by an understanding of the ecological and evolutionary factors that drive selection in weed populations. Here, we argue for a greater focus on the ultimate causes of selection for resistance in herbicide resistance studies. The emerging fields of eco-evolutionary dynamics and applied evolutionary biology offer a means to achieve this goal and to consider herbicide resistance in a broader and sometimes novel context. Four relevant research questions are presented, which examine (i) the impact of herbicide dose on selection for resistance, (ii) plant fitness in herbicide resistance studies, (iii) the efficacy of herbicide rotations and mixtures and (iv) the impacts of gene flow on resistance evolution and spread. In all cases, fundamental ecology and evolution have the potential to offer new insights into herbicide resistance evolution and management. © 2014 Society of Chemical Industry.

From philosophy to science (to natural philosophy): evolutionary developmental perspectives.

Science.gov (United States)

Love, Alan C

2008-03-01

This paper focuses on abstraction as a mode of reasoning that facilitates a productive relationship between philosophy and science. Using examples from evolutionary developmental biology, I argue that there are two areas where abstraction can be relevant to science: reasoning explication and problem clarification. The value of abstraction is characterized in terms of methodology (modeling or data gathering) and epistemology (explanatory evaluation or data interpretation).

Steps Towards Operationalising an Evolutionary Archaeological Definition of Culture

DEFF Research Database (Denmark)

Riede, Felix

2011-01-01

This paper examines the definition of archaeological cultures/techno-complexes from an evolutionary perspective, in which culture is defined as a system of social information transmission. A formal methodology is presented through which the concept of a culture can be operationalised, at least...... within this approach. It has already been argued that in order to study material culture evolution in a manner similar to how palaeontologists study biological change over time, we need explicitly constructed archaeological taxonomic units . In palaeontology, the definition of such taxonomic units ? most...... are constructed, it is possible to define an archaeological culture at any given point in this hierarchy, depending on the scale of analysis. A brief example from the Late Glacial in Southern Scandinavia is presented, and it is shown that this approach can be used to operationalise an evolutionary definition...

Sex differences in attraction to familiar and unfamiliar opposite-sex faces: men prefer novelty and women prefer familiarity.

Science.gov (United States)

Little, Anthony C; DeBruine, Lisa M; Jones, Benedict C

2014-07-01

Familiarity is attractive in many types of stimuli and exposure generally increases feelings of liking. However, men desire a greater number of sexual partners than women, suggesting a preference for novelty. We examined sex differences in preferences for familiarity. In Study 1 (N = 83 women, 63 men), we exposed individuals to faces twice and found that faces were judged as more attractive on the second rating, reflecting attraction to familiar faces, with the exception that men's ratings of female faces decreased on the second rating, demonstrating attraction to novelty. In Studies 2 (N = 42 women, 28 men) and 3 (N = 51 women, 25 men), exposure particularly decreased men's ratings of women's attractiveness for short-term relationships and their sexiness. In Study 4 (N = 64 women, 50 men), women's attraction to faces was positively related to self-rated similarity to their current partner's face, while the effect was significantly weaker for men. Potentially, men's attraction to novelty may reflect an adaptation promoting the acquisition of a high number of sexual partners.

Match Fitness: Development, Evolution, and Behavior--Comment on Frankenhuis and Del Giudice (2012)

Science.gov (United States)

Gluckman, Peter D.; Beedle, Alan S.

2012-01-01

The application of evolutionary thinking to human physical and psychological medicine suggests several pathways through which evolutionary processes affect risk of disease. Among these is the concept of mismatch between an individual and its environment, either because the environment has changed for the whole species ("evolutionary novelty") or…

The novelty-seeking phenotype modulates the long-lasting effects of adolescent MDMA exposure.

Science.gov (United States)

Rodríguez-Arias, Marta; Vaccaro, Sonia; Arenas, M Carmen; Aguilar, María A; Miñarro, José

2015-03-15

Exposure to drugs such as ethanol or cocaine during adolescence induces alterations in the central nervous system that are modulated by the novelty-seeking trait. Our aim was to evaluate the influence of this trait on the long-term effects of MDMA administration during adolescence on spontaneous behavior and conditioned rewarding effects in adulthood. Adolescent mice were classified as high or low novelty seekers (HNS or LNS) according to the hole-board test and received either MDMA (0, 10 or 20mg/kg PND 33-42) or saline. Three weeks later, having entered adulthood (PND>68), one set of mice performed the elevated plus maze and social interaction tests, while another set performed the conditioning place preference (CPP) test induced by cocaine-(1mg/kg) or MDMA-(1mg/kg). Only HNS mice treated with MDMA during adolescence acquired CPP in adulthood with a non-effective dose of cocaine or MDMA. Although it did not produce changes in motor activity, exposure to MDMA during adolescence was associated with more aggressive behaviors (threat and attack) and increased social contacts in HNS mice, while an anxiolytic effect was noted in LNS mice pre-treated with the highest dose of MDMA (20mg/kg). Administration of MDMA (10 or 20mg/kg) induced a decrease in DA levels in the striatum in LNS mice only and lower striatal serotonin levels in mice treated with the highest MDMA dose. Our findings show that adolescent MDMA exposure results in higher sensitivity to the conditioned reinforcing properties of MDMA and cocaine in adult HNS mice, which suggests that the relationship between exposure to MDMA in adolescence and a higher probability of substance is a feature of high novelty seekers only. Copyright © 2015. Published by Elsevier Inc.

Extrapolating Weak Selection in Evolutionary Games

Science.gov (United States)

Wu, Bin; García, Julián; Hauert, Christoph; Traulsen, Arne

2013-01-01

In evolutionary games, reproductive success is determined by payoffs. Weak selection means that even large differences in game outcomes translate into small fitness differences. Many results have been derived using weak selection approximations, in which perturbation analysis facilitates the derivation of analytical results. Here, we ask whether results derived under weak selection are also qualitatively valid for intermediate and strong selection. By “qualitatively valid” we mean that the ranking of strategies induced by an evolutionary process does not change when the intensity of selection increases. For two-strategy games, we show that the ranking obtained under weak selection cannot be carried over to higher selection intensity if the number of players exceeds two. For games with three (or more) strategies, previous examples for multiplayer games have shown that the ranking of strategies can change with the intensity of selection. In particular, rank changes imply that the most abundant strategy at one intensity of selection can become the least abundant for another. We show that this applies already to pairwise interactions for a broad class of evolutionary processes. Even when both weak and strong selection limits lead to consistent predictions, rank changes can occur for intermediate intensities of selection. To analyze how common such games are, we show numerically that for randomly drawn two-player games with three or more strategies, rank changes frequently occur and their likelihood increases rapidly with the number of strategies . In particular, rank changes are almost certain for , which jeopardizes the predictive power of results derived for weak selection. PMID:24339769

Evolutionary Computing Methods for Spectral Retrieval

Science.gov (United States)

Terrile, Richard; Fink, Wolfgang; Huntsberger, Terrance; Lee, Seugwon; Tisdale, Edwin; VonAllmen, Paul; Tinetti, Geivanna

2009-01-01

A methodology for processing spectral images to retrieve information on underlying physical, chemical, and/or biological phenomena is based on evolutionary and related computational methods implemented in software. In a typical case, the solution (the information that one seeks to retrieve) consists of parameters of a mathematical model that represents one or more of the phenomena of interest. The methodology was developed for the initial purpose of retrieving the desired information from spectral image data acquired by remote-sensing instruments aimed at planets (including the Earth). Examples of information desired in such applications include trace gas concentrations, temperature profiles, surface types, day/night fractions, cloud/aerosol fractions, seasons, and viewing angles. The methodology is also potentially useful for retrieving information on chemical and/or biological hazards in terrestrial settings. In this methodology, one utilizes an iterative process that minimizes a fitness function indicative of the degree of dissimilarity between observed and synthetic spectral and angular data. The evolutionary computing methods that lie at the heart of this process yield a population of solutions (sets of the desired parameters) within an accuracy represented by a fitness-function value specified by the user. The evolutionary computing methods (ECM) used in this methodology are Genetic Algorithms and Simulated Annealing, both of which are well-established optimization techniques and have also been described in previous NASA Tech Briefs articles. These are embedded in a conceptual framework, represented in the architecture of the implementing software, that enables automatic retrieval of spectral and angular data and analysis of the retrieved solutions for uniqueness.

Exploring the Relation between the Degree of Novelty of Innovations and User-producer Interaction across Different Income Regions

DEFF Research Database (Denmark)

Harirchi, Gouya; Chaminade, Cristina

2014-01-01

User–producer interactions have been recognized as important for innovation. With the rapid growth of emerging economies’ markets, and an increasing degree of technological sophistication of both users and producers in those markets, user–producer interaction is becoming global. Using original firm......-level data, this paper explores how collaboration with users in different income regions affects the degree of innovations’ novelty. We find that collaborating with international users is positively related to higher degrees of novelty. Furthermore, firms in low- and middle income countries will benefit more...... from south–south user collaboration than a south–north one....

The novelty-seeking phenotype modulates the long-lasting effects of intermittent ethanol administration during adolescence.

Directory of Open Access Journals (Sweden)

Sandra Montagud-Romero

Full Text Available The aim of the present study was to investigate if a novelty-seeking phenotype mediates the long-lasting consequences of intermittent EtOH intoxication during adolescence. The hole board test was employed to classify adolescent mice as High- or Low-Novelty Seekers. Subsequently, animals were administered ethanol (1.25 or 2.5 g/kg on two consecutive days at 48-h intervals over a 14-day period. Anxiety levels--measured using the elevated plus maze- spontaneous motor activity and social interaction test were studied 3 weeks later. A different set of mice underwent the same procedure, but received only the 2.5 g/kg dose of ethanol. Three weeks later, in order to induce CPP, the same animals were administered 1 or 6 mg/kg of cocaine or 1 or 2.5 mg/kg MDMA. The results revealed a decrease in aggressive behaviors and an anxiolytic profile in HNS mice and longer latency to explore the novel object by LNS mice. Ethanol exposure enhanced the reinforcing effects of cocaine and MDMA in both groups when CPP was induced with a sub-threshold dose of the drugs. The extinguished cocaine-induced CPP (1 and 6 mg/kg was reinstated after a priming dose in HNS animals only. Our results confirm that intermittent EtOH administration during adolescence induces long-lasting effects that are manifested in adult life, and that there is an association between these effects and the novelty-seeking phenotype.

High novelty-seeking rats are resilient to negative physiological effects of the early life stress.

Science.gov (United States)

Clinton, Sarah M; Watson, Stanley J; Akil, Huda

2014-01-01

Exposure to early life stress dramatically impacts adult behavior, physiology, and neuroendocrine function. Using rats bred for novelty-seeking differences and known to display divergent anxiety, depression, and stress vulnerability, we examined the interaction between early life adversity and genetic predisposition for high- versus low-emotional reactivity. Thus, bred Low Novelty Responder (bLR) rats, which naturally exhibit high anxiety- and depression-like behavior, and bred High Novelty Responder (bHR) rats, which show low anxiety/depression together with elevated aggression, impulsivity, and addictive behavior, were subjected to daily 3 h maternal separation (MS) stress postnatal days 1-14. We hypothesized that MS stress would differentially impact adult bHR/bLR behavior, physiology (stress-induced defecation), and neuroendocrine reactivity. While MS stress did not impact bHR and bLR anxiety-like behavior in the open field test and elevated plus maze, it exacerbated bLRs' already high physiological response to stress - stress-induced defecation. In both tests, MS bLR adult offspring showed exaggerated stress-induced defecation compared to bLR controls while bHR offspring were unaffected. MS also selectively impacted bLRs' (but not bHRs') neuroendocrine stress reactivity, producing an exaggerated corticosterone acute stress response in MS bLR versus control bLR rats. These findings highlight how genetic predisposition shapes individuals' response to early life stress. Future work will explore neural mechanisms underlying the distinct behavioral and neuroendocrine consequences of MS in bHR/bLR animals.

Polymorphic Evolutionary Games.

Science.gov (United States)

Fishman, Michael A

2016-06-07

In this paper, I present an analytical framework for polymorphic evolutionary games suitable for explicitly modeling evolutionary processes in diploid populations with sexual reproduction. The principal aspect of the proposed approach is adding diploid genetics cum sexual recombination to a traditional evolutionary game, and switching from phenotypes to haplotypes as the new game׳s pure strategies. Here, the relevant pure strategy׳s payoffs derived by summing the payoffs of all the phenotypes capable of producing gametes containing that particular haplotype weighted by the pertinent probabilities. The resulting game is structurally identical to the familiar Evolutionary Games with non-linear pure strategy payoffs (Hofbauer and Sigmund, 1998. Cambridge University Press), and can be analyzed in terms of an established analytical framework for such games. And these results can be translated into the terms of genotypic, and whence, phenotypic evolutionary stability pertinent to the original game. Copyright © 2016 Elsevier Ltd. All rights reserved.

Grooming behavior in American cockroach is affected by novelty and odor.

Science.gov (United States)

Zhukovskaya, Marianna I

2014-01-01

The main features of grooming behavior are amazingly similar among arthropods and land vertebrates and serve the same needs. A particular pattern of cleaning movements in cockroaches shows cephalo-caudal progression. Grooming sequences become longer after adaptation to the new setting. Novelty related changes in grooming are recognized as a form of displacement behavior. Statistical analysis of behavior revealed that antennal grooming in American cockroach, Periplaneta americana L., was significantly enhanced in the presence of odor.

Remembering the evolutionary Freud.

Science.gov (United States)

Young, Allan

2006-03-01

Throughout his career as a writer, Sigmund Freud maintained an interest in the evolutionary origins of the human mind and its neurotic and psychotic disorders. In common with many writers then and now, he believed that the evolutionary past is conserved in the mind and the brain. Today the "evolutionary Freud" is nearly forgotten. Even among Freudians, he is regarded to be a red herring, relevant only to the extent that he diverts attention from the enduring achievements of the authentic Freud. There are three ways to explain these attitudes. First, the evolutionary Freud's key work is the "Overview of the Transference Neurosis" (1915). But it was published at an inopportune moment, forty years after the author's death, during the so-called "Freud wars." Second, Freud eventually lost interest in the "Overview" and the prospect of a comprehensive evolutionary theory of psychopathology. The publication of The Ego and the Id (1923), introducing Freud's structural theory of the psyche, marked the point of no return. Finally, Freud's evolutionary theory is simply not credible. It is based on just-so stories and a thoroughly discredited evolutionary mechanism, Lamarckian use-inheritance. Explanations one and two are probably correct but also uninteresting. Explanation number three assumes that there is a fundamental difference between Freud's evolutionary narratives (not credible) and the evolutionary accounts of psychopathology that currently circulate in psychiatry and mainstream journals (credible). The assumption is mistaken but worth investigating.

Evolutionary systems biology: historical and philosophical perspectives on an emerging synthesis.

Science.gov (United States)

O'Malley, Maureen A

2012-01-01

Systems biology (SB) is at least a decade old now and maturing rapidly. A more recent field, evolutionary systems biology (ESB), is in the process of further developing system-level approaches through the expansion of their explanatory and potentially predictive scope. This chapter will outline the varieties of ESB existing today by tracing the diverse roots and fusions that make up this integrative project. My approach is philosophical and historical. As well as examining the recent origins of ESB, I will reflect on its central features and the different clusters of research it comprises. In its broadest interpretation, ESB consists of five overlapping approaches: comparative and correlational ESB; network architecture ESB; network property ESB; population genetics ESB; and finally, standard evolutionary questions answered with SB methods. After outlining each approach with examples, I will examine some strong general claims about ESB, particularly that it can be viewed as the next step toward a fuller modern synthesis of evolutionary biology (EB), and that it is also the way forward for evolutionary and systems medicine. I will conclude with a discussion of whether the emerging field of ESB has the capacity to combine an even broader scope of research aims and efforts than it presently does.

The Evolutionary Psychology of Envy and Jealousy

Science.gov (United States)

Ramachandran, Vilayanur S.; Jalal, Baland

2017-01-01

The old dogma has always been that the most complex aspects of human emotions are driven by culture; Germans and English are thought to be straight-laced whereas Italians and Indians are effusive. Yet in the last two decades there has been a growing realization that even though culture plays a major role in the final expression of human nature, there must be a basic scaffolding specified by genes. While this is recognized to be true for simple emotions like anger, fear, and joy, the relevance of evolutionary arguments for more complex nuances of emotion have been inadequately explored. In this paper, we consider envy or jealousy as an example; the feeling evoked when someone is better off than you. Our approach is broadly consistent with traditional evolutionary psychology (EP) approaches, but takes it further by exploring the complexity and functional logic of the emotion – and the precise social triggers that elicit them – by using deliberately farfetched, and contrived “thought experiments” that the subject is asked to participate in. When common sense (e.g., we should be jealous of Bill Gates – not of our slightly richer neighbor) appears to contradict observed behavior (i.e., we are more envious of our neighbor) the paradox can often be resolved by evolutionary considerations which h predict the latter. Many – but not all – EP approaches fail because evolution and common sense do not make contradictory predictions. Finally, we briefly raise the possibility that gaining deeper insight into the evolutionary origins of certain undesirable emotions or behaviors can help shake them off, and may therefore have therapeutic utility. Such an approach would complement current therapies (such as cognitive behavior therapies, psychoanalysis, psychopharmacologies, and hypnotherapy), rather than negate them. PMID:28970815

The Evolutionary Psychology of Envy and Jealousy

Directory of Open Access Journals (Sweden)

Vilayanur S. Ramachandran

2017-09-01

Full Text Available The old dogma has always been that the most complex aspects of human emotions are driven by culture; Germans and English are thought to be straight-laced whereas Italians and Indians are effusive. Yet in the last two decades there has been a growing realization that even though culture plays a major role in the final expression of human nature, there must be a basic scaffolding specified by genes. While this is recognized to be true for simple emotions like anger, fear, and joy, the relevance of evolutionary arguments for more complex nuances of emotion have been inadequately explored. In this paper, we consider envy or jealousy as an example; the feeling evoked when someone is better off than you. Our approach is broadly consistent with traditional evolutionary psychology (EP approaches, but takes it further by exploring the complexity and functional logic of the emotion – and the precise social triggers that elicit them – by using deliberately farfetched, and contrived “thought experiments” that the subject is asked to participate in. When common sense (e.g., we should be jealous of Bill Gates – not of our slightly richer neighbor appears to contradict observed behavior (i.e., we are more envious of our neighbor the paradox can often be resolved by evolutionary considerations which h predict the latter. Many – but not all – EP approaches fail because evolution and common sense do not make contradictory predictions. Finally, we briefly raise the possibility that gaining deeper insight into the evolutionary origins of certain undesirable emotions or behaviors can help shake them off, and may therefore have therapeutic utility. Such an approach would complement current therapies (such as cognitive behavior therapies, psychoanalysis, psychopharmacologies, and hypnotherapy, rather than negate them.

Understanding the mind from an evolutionary perspective: an overview of evolutionary psychology.

Science.gov (United States)

Shackelford, Todd K; Liddle, James R

2014-05-01

The theory of evolution by natural selection provides the only scientific explanation for the existence of complex adaptations. The design features of the brain, like any organ, are the result of selection pressures operating over deep time. Evolutionary psychology posits that the human brain comprises a multitude of evolved psychological mechanisms, adaptations to specific and recurrent problems of survival and reproduction faced over human evolutionary history. Although some mistakenly view evolutionary psychology as promoting genetic determinism, evolutionary psychologists appreciate and emphasize the interactions between genes and environments. This approach to psychology has led to a richer understanding of a variety of psychological phenomena, and has provided a powerful foundation for generating novel hypotheses. Critics argue that evolutionary psychologists resort to storytelling, but as with any branch of science, empirical testing is a vital component of the field, with hypotheses standing or falling with the weight of the evidence. Evolutionary psychology is uniquely suited to provide a unifying theoretical framework for the disparate subdisciplines of psychology. An evolutionary perspective has provided insights into several subdisciplines of psychology, while simultaneously demonstrating the arbitrary nature of dividing psychological science into such subdisciplines. Evolutionary psychologists have amassed a substantial empirical and theoretical literature, but as a relatively new approach to psychology, many questions remain, with several promising directions for future research. For further resources related to this article, please visit the WIREs website. The authors have declared no conflicts of interest for this article. © 2014 John Wiley & Sons, Ltd.

A pharyngeal jaw evolutionary innovation facilitated extinction in Lake Victoria cichlids.

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McGee, Matthew D; Borstein, Samuel R; Neches, Russell Y; Buescher, Heinz H; Seehausen, Ole; Wainwright, Peter C

2015-11-27

Evolutionary innovations, traits that give species access to previously unoccupied niches, may promote speciation and adaptive radiation. Here, we show that such innovations can also result in competitive inferiority and extinction. We present evidence that the modified pharyngeal jaws of cichlid fishes and several marine fish lineages, a classic example of evolutionary innovation, are not universally beneficial. A large-scale analysis of dietary evolution across marine fish lineages reveals that the innovation compromises access to energy-rich predator niches. We show that this competitive inferiority shaped the adaptive radiation of cichlids in Lake Tanganyika and played a pivotal and previously unrecognized role in the mass extinction of cichlid fishes in Lake Victoria after Nile perch invasion. Copyright © 2015, American Association for the Advancement of Science.

Evolutionary analysis of technological innovations: the example of solar photovoltaic and wind energy

International Nuclear Information System (INIS)

Taillant, Pierre

2005-01-01

The objective of this research thesis is to study the building up and the development of technologies for renewable energies considered as environmental radical innovations. In a first part, the author discusses the systemic aspects of innovation and the environmental challenges associated with energy technologies. He examines the main evolutions of energy systems over a long period. In a second part, he addresses innovation incentives in the case of environmental technologies and within the frame of the neo-classical economic theory. The next parts aim at presenting the theoretical framework of the evolutionary analysis of innovation and technical change, and at applying it to the case of technological innovations for renewable energies (photovoltaic and wind energy). World PV market trends are discussed and the technological competition context of this sector is analysed. The evolution of the solar PV technological system in Germany is discussed, as well as the specific case of development of the wind energy technological system in Denmark

Single prolonged stress impairs social and object novelty recognition in rats.

Science.gov (United States)

Eagle, Andrew L; Fitzpatrick, Chris J; Perrine, Shane A

2013-11-01

Posttraumatic stress disorder (PTSD) results from exposure to a traumatic event and manifests as re-experiencing, arousal, avoidance, and negative cognition/mood symptoms. Avoidant symptoms, as well as the newly defined negative cognitions/mood, are a serious complication leading to diminished interest in once important or positive activities, such as social interaction; however, the basis of these symptoms remains poorly understood. PTSD patients also exhibit impaired object and social recognition, which may underlie the avoidance and symptoms of negative cognition, such as social estrangement or diminished interest in activities. Previous studies have demonstrated that single prolonged stress (SPS), models PTSD phenotypes, including impairments in learning and memory. Therefore, it was hypothesized that SPS would impair social and object recognition memory. Male Sprague Dawley rats were exposed to SPS then tested in the social choice test (SCT) or novel object recognition test (NOR). These tests measure recognition of novelty over familiarity, a natural preference of rodents. Results show that SPS impaired preference for both social and object novelty. In addition, SPS impairment in social recognition may be caused by impaired behavioral flexibility, or an inability to shift behavior during the SCT. These results demonstrate that traumatic stress can impair social and object recognition memory, which may underlie certain avoidant symptoms or negative cognition in PTSD and be related to impaired behavioral flexibility. Copyright © 2013 Elsevier B.V. All rights reserved.

Comparison of some evolutionary algorithms for optimization of the path synthesis problem

Science.gov (United States)

Grabski, Jakub Krzysztof; Walczak, Tomasz; Buśkiewicz, Jacek; Michałowska, Martyna

2018-01-01

The paper presents comparison of the results obtained in a mechanism synthesis by means of some selected evolutionary algorithms. The optimization problem considered in the paper as an example is the dimensional synthesis of the path generating four-bar mechanism. In order to solve this problem, three different artificial intelligence algorithms are employed in this study.

Random drift versus selection in academic vocabulary: an evolutionary analysis of published keywords.

Science.gov (United States)

Bentley, R Alexander

2008-08-27

The evolution of vocabulary in academic publishing is characterized via keyword frequencies recorded in the ISI Web of Science citations database. In four distinct case-studies, evolutionary analysis of keyword frequency change through time is compared to a model of random copying used as the null hypothesis, such that selection may be identified against it. The case studies from the physical sciences indicate greater selection in keyword choice than in the social sciences. Similar evolutionary analyses can be applied to a wide range of phenomena; wherever the popularity of multiple items through time has been recorded, as with web searches, or sales of popular music and books, for example.

[Evolutionary medicine].

Science.gov (United States)

Wjst, M

2013-12-01

Evolutionary medicine allows new insights into long standing medical problems. Are we "really stoneagers on the fast lane"? This insight might have enormous consequences and will allow new answers that could never been provided by traditional anthropology. Only now this is made possible using data from molecular medicine and systems biology. Thereby evolutionary medicine takes a leap from a merely theoretical discipline to practical fields - reproductive, nutritional and preventive medicine, as well as microbiology, immunology and psychiatry. Evolutionary medicine is not another "just so story" but a serious candidate for the medical curriculum providing a universal understanding of health and disease based on our biological origin. © Georg Thieme Verlag KG Stuttgart · New York.

Core principles of evolutionary medicine

Science.gov (United States)

Grunspan, Daniel Z; Nesse, Randolph M; Barnes, M Elizabeth; Brownell, Sara E

2018-01-01

Abstract Background and objectives Evolutionary medicine is a rapidly growing field that uses the principles of evolutionary biology to better understand, prevent and treat disease, and that uses studies of disease to advance basic knowledge in evolutionary biology. Over-arching principles of evolutionary medicine have been described in publications, but our study is the first to systematically elicit core principles from a diverse panel of experts in evolutionary medicine. These principles should be useful to advance recent recommendations made by The Association of American Medical Colleges and the Howard Hughes Medical Institute to make evolutionary thinking a core competency for pre-medical education. Methodology The Delphi method was used to elicit and validate a list of core principles for evolutionary medicine. The study included four surveys administered in sequence to 56 expert panelists. The initial open-ended survey created a list of possible core principles; the three subsequent surveys winnowed the list and assessed the accuracy and importance of each principle. Results Fourteen core principles elicited at least 80% of the panelists to agree or strongly agree that they were important core principles for evolutionary medicine. These principles over-lapped with concepts discussed in other articles discussing key concepts in evolutionary medicine. Conclusions and implications This set of core principles will be helpful for researchers and instructors in evolutionary medicine. We recommend that evolutionary medicine instructors use the list of core principles to construct learning goals. Evolutionary medicine is a young field, so this list of core principles will likely change as the field develops further. PMID:29493660

A taste for novelty in invading house sparrows, Passer domesticus

OpenAIRE

Lynn B. Martin; Lisa Fitzgerald

2005-01-01

One of the central questions in invasion biology involves why some introductions succeed and others fail. Although several correlates of invasion success have been identified, patterns alone cannot identify the mechanisms underlying the invasion process. Here, we test the hypothesis that one predictor of invasion success, behavioral flexibility, is different between invading and established populations of the same species of bird. We predicted that neophobia (fear of novelty), a surrogate of ...

Multi-objective optimization of an arch dam shape under static loads using an evolutionary game method

Science.gov (United States)

Meng, Rui; Cheong, Kang Hao; Bao, Wei; Wong, Kelvin Kian Loong; Wang, Lu; Xie, Neng-gang

2018-06-01

This article attempts to evaluate the safety and economic performance of an arch dam under the action of static loads. The geometric description of a crown cantilever section and the horizontal arch ring is presented. A three-objective optimization model of arch dam shape is established based on the arch dam volume, maximum principal tensile stress and total strain energy. The evolutionary game method is then applied to obtain the optimal solution. In the evolutionary game technique, a novel and more efficient exploration method of the game players' strategy space, named the 'sorting partition method under the threshold limit', is presented, with the game profit functions constructed according to both competitive and cooperative behaviour. By way of example, three optimization goals have all shown improvements over the initial solutions. In particular, the evolutionary game method has potentially faster convergence. This demonstrates the preliminary proof of principle of the evolutionary game method.

INACTIVITY OF RECOMBINANT ELA2B PROVIDES A NEW EXAMPLE OF EVOLUTIONARY ELASTASE SILENCING IN HUMANS

OpenAIRE

Szepessy, Edit; Sahin-Tóth, Miklós

2005-01-01

BACKGROUND. The archetypal mammalian elastase (ELA1) is not expressed in the human pancreas, because evolutionary mutations suppressed transcription of the ELA1 gene. AIMS. In this study we tested the theory that the unique duplication of the ELA2 gene in humans might compensate for the loss of ELA1. METHODS. Recombinant ELA2A and ELA2B were expressed in Escherichia coli, and their activity was tested on Glt-Ala-Ala-Pro-Leu-p-nitroanilide, DQ elastin and bovine milk protein. RESULTS. Surprisi...

Applying evolutionary anthropology.

Science.gov (United States)

Gibson, Mhairi A; Lawson, David W

2015-01-01

Evolutionary anthropology provides a powerful theoretical framework for understanding how both current environments and legacies of past selection shape human behavioral diversity. This integrative and pluralistic field, combining ethnographic, demographic, and sociological methods, has provided new insights into the ultimate forces and proximate pathways that guide human adaptation and variation. Here, we present the argument that evolutionary anthropological studies of human behavior also hold great, largely untapped, potential to guide the design, implementation, and evaluation of social and public health policy. Focusing on the key anthropological themes of reproduction, production, and distribution we highlight classic and recent research demonstrating the value of an evolutionary perspective to improving human well-being. The challenge now comes in transforming relevance into action and, for that, evolutionary behavioral anthropologists will need to forge deeper connections with other applied social scientists and policy-makers. We are hopeful that these developments are underway and that, with the current tide of enthusiasm for evidence-based approaches to policy, evolutionary anthropology is well positioned to make a strong contribution. © 2015 Wiley Periodicals, Inc.

Applying Evolutionary Anthropology

Science.gov (United States)

Gibson, Mhairi A; Lawson, David W

2015-01-01

Evolutionary anthropology provides a powerful theoretical framework for understanding how both current environments and legacies of past selection shape human behavioral diversity. This integrative and pluralistic field, combining ethnographic, demographic, and sociological methods, has provided new insights into the ultimate forces and proximate pathways that guide human adaptation and variation. Here, we present the argument that evolutionary anthropological studies of human behavior also hold great, largely untapped, potential to guide the design, implementation, and evaluation of social and public health policy. Focusing on the key anthropological themes of reproduction, production, and distribution we highlight classic and recent research demonstrating the value of an evolutionary perspective to improving human well-being. The challenge now comes in transforming relevance into action and, for that, evolutionary behavioral anthropologists will need to forge deeper connections with other applied social scientists and policy-makers. We are hopeful that these developments are underway and that, with the current tide of enthusiasm for evidence-based approaches to policy, evolutionary anthropology is well positioned to make a strong contribution. PMID:25684561

Adaptability: How Students' Responses to Uncertainty and Novelty Predict Their Academic and Non-Academic Outcomes

Science.gov (United States)

Martin, Andrew J.; Nejad, Harry G.; Colmar, Susan; Liem, Gregory Arief D.

2013-01-01

Adaptability is defined as appropriate cognitive, behavioral, and/or affective adjustment in the face of uncertainty and novelty. Building on prior measurement work demonstrating the psychometric properties of an adaptability construct, the present study investigates dispositional predictors (personality, implicit theories) of adaptability, and…

Neuropsychological performance, impulsivity, ADHD symptoms, and novelty seeking in compulsive buying disorder.

Science.gov (United States)

Black, Donald Wayne; Shaw, Martha; McCormick, Brett; Bayless, John David; Allen, Jeff

2012-12-30

We examined the neuropsychological performance of people with compulsive buying disorder (CBD) and control subjects, along with trait impulsivity, symptoms of attention deficit hyperactivity disorder (ADHD), and selected personality characteristics. Subjects received a comprehensive neuropsychological test battery, depression and ADHD symptom assessment, the Barratt Impulsiveness Scale, and a version of the Temperament and Character Inventory. Persons with CBD (n=26) and controls (n=32) were comparable in terms of age, sex, and years of education. Subjects with CBD had a mean age of 36.3 years (S.D.=15.7) and an age at onset of 19.7 years (S.D.=7.0). Compulsive buyers had more lifetime mood, anxiety, and impulse control disorders. People with Compulsive buying performed significantly better on the Wechsler Abbreviated Scale of Intelligence Picture Completion task, a test of visual perception; otherwise, there were no consistent differences in neuropsychological measures. They also had elevated levels of self-reported depression, ADHD symptoms, trait impulsivity, and novelty seeking. In conclusion, compulsive buyers have greater lifetime psychiatric comorbidity than controls, and higher levels of self-rated depression, ADHD symptoms, trait impulsivity, and novelty seeking. The present study does not support the notion that there is a pattern of neuropsychological deficits associated with CBD. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Evolutionary history of chordate PAX genes: dynamics of change in a complex gene family.

Directory of Open Access Journals (Sweden)

Vanessa Rodrigues Paixão-Côrtes

Full Text Available Paired box (PAX genes are transcription factors that play important roles in embryonic development. Although the PAX gene family occurs in animals only, it is widely distributed. Among the vertebrates, its 9 genes appear to be the product of complete duplication of an original set of 4 genes, followed by an additional partial duplication. Although some studies of PAX genes have been conducted, no comprehensive survey of these genes across the entire taxonomic unit has yet been attempted. In this study, we conducted a detailed comparison of PAX sequences from 188 chordates, which revealed restricted variation. The absence of PAX4 and PAX8 among some species of reptiles and birds was notable; however, all 9 genes were present in all 74 mammalian genomes investigated. A search for signatures of selection indicated that all genes are subject to purifying selection, with a possible constraint relaxation in PAX4, PAX7, and PAX8. This result indicates asymmetric evolution of PAX family genes, which can be associated with the emergence of adaptive novelties in the chordate evolutionary trajectory.

Evolved pesticide tolerance in amphibians: Predicting mechanisms based on pesticide novelty and mode of action

International Nuclear Information System (INIS)

Hua, Jessica; Jones, Devin K.; Mattes, Brian M.; Cothran, Rickey D.; Relyea, Rick A.; Hoverman, Jason T.

2015-01-01

We examined 10 wood frog populations distributed along an agricultural gradient for their tolerance to six pesticides (carbaryl, malathion, cypermethrin, permethrin, imidacloprid, and thiamethoxam) that differed in date of first registration (pesticide novelty) and mode-of-action (MOA). Our goals were to assess whether: 1) tolerance was correlated with distance to agriculture for each pesticide, 2) pesticide novelty predicted the likelihood of evolved tolerance, and 3) populations display cross-tolerance between pesticides that share and differ in MOA. Wood frog populations located close to agriculture were more tolerant to carbaryl and malathion than populations far from agriculture. Moreover, the strength of the relationship between distance to agriculture and tolerance was stronger for older pesticides compared to newer pesticides. Finally, we found evidence for cross-tolerance between carbaryl and malathion (two pesticides that share MOA). This study provides one of the most comprehensive approaches for understanding patterns of evolved tolerance in non-pest species. - Highlights: • We explored patterns of tolerance to six insecticides across 10 wood frog populations. • We found evidence that wood frogs have evolved tolerance to carbaryl and malathion. • The likelihood of evolved tolerance was stronger for older compared to newer pesticides. • We found evidence for cross-tolerance between carbaryl and malathion. • This is one of the most comprehensive approaches studying evolved tolerance in a non-pest species. - Using 10 wood frog populations, we detected evidence for evolved tolerance, found that the evolved tolerance depends on insecticide novelty, and found evidence for cross-tolerance.

Evolutionary Expectations

DEFF Research Database (Denmark)

Nash, Ulrik William

2014-01-01

, they are correlated among people who share environments because these individuals satisfice within their cognitive bounds by using cues in order of validity, as opposed to using cues arbitrarily. Any difference in expectations thereby arise from differences in cognitive ability, because two individuals with identical...... cognitive bounds will perceive business opportunities identically. In addition, because cues provide information about latent causal structures of the environment, changes in causality must be accompanied by changes in cognitive representations if adaptation is to be maintained. The concept of evolutionary......The concept of evolutionary expectations descends from cue learning psychology, synthesizing ideas on rational expectations with ideas on bounded rationality, to provide support for these ideas simultaneously. Evolutionary expectations are rational, but within cognitive bounds. Moreover...

Evolutionary Awareness

Directory of Open Access Journals (Sweden)

Gregory Gorelik

2014-10-01

Full Text Available In this article, we advance the concept of “evolutionary awareness,” a metacognitive framework that examines human thought and emotion from a naturalistic, evolutionary perspective. We begin by discussing the evolution and current functioning of the moral foundations on which our framework rests. Next, we discuss the possible applications of such an evolutionarily-informed ethical framework to several domains of human behavior, namely: sexual maturation, mate attraction, intrasexual competition, culture, and the separation between various academic disciplines. Finally, we discuss ways in which an evolutionary awareness can inform our cross-generational activities—which we refer to as “intergenerational extended phenotypes”—by helping us to construct a better future for ourselves, for other sentient beings, and for our environment.

EVOLUTIONARY FOUNDATIONS FOR MOLECULAR MEDICINE

Science.gov (United States)

Nesse, Randolph M.; Ganten, Detlev; Gregory, T. Ryan; Omenn, Gilbert S.

2015-01-01

Evolution has long provided a foundation for population genetics, but many major advances in evolutionary biology from the 20th century are only now being applied in molecular medicine. They include the distinction between proximate and evolutionary explanations, kin selection, evolutionary models for cooperation, and new strategies for tracing phylogenies and identifying signals of selection. Recent advances in genomics are further transforming evolutionary biology and creating yet more opportunities for progress at the interface of evolution with genetics, medicine, and public health. This article reviews 15 evolutionary principles and their applications in molecular medicine in hopes that readers will use them and others to speed the development of evolutionary molecular medicine. PMID:22544168

Fluid consumption and taste novelty determines transcription temporal dynamics in the gustatory cortex.

Science.gov (United States)

Inberg, Sharon; Jacob, Eyal; Elkobi, Alina; Edry, Efrat; Rappaport, Akiva; Simpson, T Ian; Armstrong, J Douglas; Shomron, Noam; Pasmanik-Chor, Metsada; Rosenblum, Kobi

2016-02-09

Novel taste memories, critical for animal survival, are consolidated to form long term memories which are dependent on translation regulation in the gustatory cortex (GC) hours following acquisition. However, the role of transcription regulation in the process is unknown. Here, we report that transcription in the GC is necessary for taste learning in rats, and that drinking and its consequences, as well as the novel taste experience, affect transcription in the GC during taste memory consolidation. We show differential effects of learning on temporal dynamics in set of genes in the GC, including Arc/Arg3.1, known to regulate the homeostasis of excitatory synapses. We demonstrate that in taste learning, transcription programs were activated following the physiological responses (i.e., fluid consumption following a water restriction regime, reward, arousal of the animal, etc.) and the specific information about a given taste (i.e., taste novelty). Moreover, the cortical differential prolonged kinetics of mRNA following novel versus familiar taste learning may represent additional novelty related molecular response, where not only the total amount, but also the temporal dynamics of transcription is modulated by sensory experience of novel information.

Attractive evolutionary equilibria

NARCIS (Netherlands)

Joosten, Reinoud A.M.G.; Roorda, Berend

2011-01-01

We present attractiveness, a refinement criterion for evolutionary equilibria. Equilibria surviving this criterion are robust to small perturbations of the underlying payoff system or the dynamics at hand. Furthermore, certain attractive equilibria are equivalent to others for certain evolutionary

Bipartite Graphs as Models of Population Structures in Evolutionary Multiplayer Games

Science.gov (United States)

Peña, Jorge; Rochat, Yannick

2012-01-01

By combining evolutionary game theory and graph theory, “games on graphs” study the evolutionary dynamics of frequency-dependent selection in population structures modeled as geographical or social networks. Networks are usually represented by means of unipartite graphs, and social interactions by two-person games such as the famous prisoner’s dilemma. Unipartite graphs have also been used for modeling interactions going beyond pairwise interactions. In this paper, we argue that bipartite graphs are a better alternative to unipartite graphs for describing population structures in evolutionary multiplayer games. To illustrate this point, we make use of bipartite graphs to investigate, by means of computer simulations, the evolution of cooperation under the conventional and the distributed N-person prisoner’s dilemma. We show that several implicit assumptions arising from the standard approach based on unipartite graphs (such as the definition of replacement neighborhoods, the intertwining of individual and group diversity, and the large overlap of interaction neighborhoods) can have a large impact on the resulting evolutionary dynamics. Our work provides a clear example of the importance of construction procedures in games on graphs, of the suitability of bigraphs and hypergraphs for computational modeling, and of the importance of concepts from social network analysis such as centrality, centralization and bipartite clustering for the understanding of dynamical processes occurring on networked population structures. PMID:22970237

Dinosaurs reveal the geographical signature of an evolutionary radiation.

Science.gov (United States)

O'Donovan, Ciara; Meade, Andrew; Venditti, Chris

2018-03-01

Dinosaurs dominated terrestrial ecosystems across the globe for over 100 million years and provide a classic example of an evolutionary radiation. However, little is known about how these animals radiated geographically to become globally distributed. Here, we use a biogeographical model to reconstruct the dinosaurs' ancestral locations, revealing the spatial mechanisms that underpinned this 170-million-year-long radiation. We find that dinosaurs spread rapidly initially, followed by a significant continuous and gradual reduction in their speed of movement towards the Cretaceous/Tertiary boundary (66 million years ago). This suggests that the predominant mode of dinosaur speciation changed through time with speciation originally largely driven by geographical isolation-when dinosaurs speciated more, they moved further. This was gradually replaced by increasing levels of sympatric speciation (species taking advantage of ecological opportunities within their existing environment) as terrestrial space became a limiting factor. Our results uncover the geographical signature of an evolutionary radiation.

Activation of midbrain structures by associative novelty and the formation of explicit memory in humans.

Science.gov (United States)

Schott, Björn H; Sellner, Daniela B; Lauer, Corinna-J; Habib, Reza; Frey, Julietta U; Guderian, Sebastian; Heinze, Hans-Jochen; Düzel, Emrah

2004-01-01

Recent evidence suggests a close functional relationship between memory formation in the hippocampus and dopaminergic neuromodulation originating in the ventral tegmental area and medial substantia nigra of the midbrain. Here we report midbrain activation in two functional MRI studies of visual memory in healthy young adults. In the first study, participants distinguished between familiar and novel configurations of pairs of items which had been studied together by either learning the location or the identity of the items. In the second study, participants studied words by either rating the words' pleasantness or counting syllables. The ventral tegmental area and medial substantia nigra showed increased activation by associative novelty (first study) and subsequent free recall performance (second study). In both studies, this activation accompanied hippocampal activation, but was unaffected by the study task. Thus midbrain regions seem to participate selectively in hippocampus-dependent processes of associative novelty and explicit memory formation, but appear to be unaffected by other task-relevant aspects.

Random drift versus selection in academic vocabulary: an evolutionary analysis of published keywords.

Directory of Open Access Journals (Sweden)

R Alexander Bentley

Full Text Available The evolution of vocabulary in academic publishing is characterized via keyword frequencies recorded in the ISI Web of Science citations database. In four distinct case-studies, evolutionary analysis of keyword frequency change through time is compared to a model of random copying used as the null hypothesis, such that selection may be identified against it. The case studies from the physical sciences indicate greater selection in keyword choice than in the social sciences. Similar evolutionary analyses can be applied to a wide range of phenomena; wherever the popularity of multiple items through time has been recorded, as with web searches, or sales of popular music and books, for example.

Theory of quasi-Chaplygin unstable media and evolutionary principle for selecting spontaneous solutions

International Nuclear Information System (INIS)

Zhdanov, S.K.; Trubnikov, B.A.; Institut Atomnoi Energii, Moscow, USSR)

1986-01-01

A one-dimensional ideal gas with negative compressibility described by quasi-Chaplygin equations is discussed. Its reduction to a Laplace equation is shown, and an evolutionary principle for selecting spontaneous solutions is summarized. Three extremely simple spontaneous solutions are obtained along with multidimensional self-similar solutions. The Buneman instability in a plasma is considered as an example. 17 references

Open Issues in Evolutionary Robotics.

Science.gov (United States)

Silva, Fernando; Duarte, Miguel; Correia, Luís; Oliveira, Sancho Moura; Christensen, Anders Lyhne

2016-01-01

One of the long-term goals in evolutionary robotics is to be able to automatically synthesize controllers for real autonomous robots based only on a task specification. While a number of studies have shown the applicability of evolutionary robotics techniques for the synthesis of behavioral control, researchers have consistently been faced with a number of issues preventing the widespread adoption of evolutionary robotics for engineering purposes. In this article, we review and discuss the open issues in evolutionary robotics. First, we analyze the benefits and challenges of simulation-based evolution and subsequent deployment of controllers versus evolution on real robotic hardware. Second, we discuss specific evolutionary computation issues that have plagued evolutionary robotics: (1) the bootstrap problem, (2) deception, and (3) the role of genomic encoding and genotype-phenotype mapping in the evolution of controllers for complex tasks. Finally, we address the absence of standard research practices in the field. We also discuss promising avenues of research. Our underlying motivation is the reduction of the current gap between evolutionary robotics and mainstream robotics, and the establishment of evolutionary robotics as a canonical approach for the engineering of autonomous robots.

A multilevel evolutionary framework for sustainability analysis

Directory of Open Access Journals (Sweden)

Timothy M. Waring

2015-06-01

Full Text Available Sustainability theory can help achieve desirable social-ecological states by generalizing lessons across contexts and improving the design of sustainability interventions. To accomplish these goals, we argue that theory in sustainability science must (1 explain the emergence and persistence of social-ecological states, (2 account for endogenous cultural change, (3 incorporate cooperation dynamics, and (4 address the complexities of multilevel social-ecological interactions. We suggest that cultural evolutionary theory broadly, and cultural multilevel selection in particular, can improve on these fronts. We outline a multilevel evolutionary framework for describing social-ecological change and detail how multilevel cooperative dynamics can determine outcomes in environmental dilemmas. We show how this framework complements existing sustainability frameworks with a description of the emergence and persistence of sustainable institutions and behavior, a means to generalize causal patterns across social-ecological contexts, and a heuristic for designing and evaluating effective sustainability interventions. We support these assertions with case examples from developed and developing countries in which we track cooperative change at multiple levels of social organization as they impact social-ecological outcomes. Finally, we make suggestions for further theoretical development, empirical testing, and application.

Cyclic dominance in evolutionary games: a review

Science.gov (United States)

Szolnoki, Attila; Mobilia, Mauro; Jiang, Luo-Luo; Szczesny, Bartosz; Rucklidge, Alastair M.; Perc, Matjaž

2014-01-01

Rock is wrapped by paper, paper is cut by scissors and scissors are crushed by rock. This simple game is popular among children and adults to decide on trivial disputes that have no obvious winner, but cyclic dominance is also at the heart of predator–prey interactions, the mating strategy of side-blotched lizards, the overgrowth of marine sessile organisms and competition in microbial populations. Cyclical interactions also emerge spontaneously in evolutionary games entailing volunteering, reward, punishment, and in fact are common when the competing strategies are three or more, regardless of the particularities of the game. Here, we review recent advances on the rock–paper–scissors (RPS) and related evolutionary games, focusing, in particular, on pattern formation, the impact of mobility and the spontaneous emergence of cyclic dominance. We also review mean-field and zero-dimensional RPS models and the application of the complex Ginzburg–Landau equation, and we highlight the importance and usefulness of statistical physics for the successful study of large-scale ecological systems. Directions for future research, related, for example, to dynamical effects of coevolutionary rules and invasion reversals owing to multi-point interactions, are also outlined. PMID:25232048

On the evolution of misunderstandings about evolutionary psychology.

Science.gov (United States)

Young, J; Persell, R

2000-04-01

Some of the controversy surrounding evolutionary explanations of human behavior may be due to cognitive information-processing patterns that are themselves the result of evolutionary processes. Two such patterns are (1) the tendency to oversimplify information so as to reduce demand on cognitive resources and (2) our strong desire to generate predictability and stability from perceptions of the external world. For example, research on social stereotyping has found that people tend to focus automatically on simplified social-categorical information, to use such information when deciding how to behave, and to rely on such information even in the face of contradictory evidence. Similarly, an undying debate over nature vs. nurture is shaped by various data-reduction strategies that frequently oversimplify, and thus distort, the intent of the supporting arguments. This debate is also often marked by an assumption that either the nature or the nurture domain may be justifiably excluded at an explanatory level because one domain appears to operate in a sufficiently stable and predictable way for a particular argument. As a result, critiques in-veighed against evolutionary explanations of behavior often incorporate simplified--and erroneous--assumptions about either the mechanics of how evolution operates or the inevitable implications of evolution for understanding human behavior. The influences of these tendencies are applied to a discussion of the heritability of behavioral characteristics. It is suggested that the common view that Mendelian genetics can explain the heritability of complex behaviors, with a one-gene-one-trait process, is misguided. Complex behaviors are undoubtedly a product of a more complex interaction between genes and environment, ensuring that both nature and nurture must be accommodated in a yet-to-be-developed post-Mendelian model of genetic influence. As a result, current public perceptions of evolutionary explanations of behavior are

A Novel Evolutionary Engineering Design Approach for Mixed-Domain Systems

DEFF Research Database (Denmark)

Fan, Zhun; Hu, J.; Seo, K.

2004-01-01

This paper presents an approach to engineering design of mixed-domain dynamic systems. The approach aims at system-level design and has two key features: first, it generates engineering designs that satisfy predefined specifications in an automatic manner; second, it can design systems belonging ...... often encountered in evolutionary computation, a HFC (Hierarchical Fair Competition) model is adopted in this work. Examples of an analog filter design and a MEM filter design illustrate the application of the approach....

Analog Group Delay Equalizers Design Based on Evolutionary Algorithm

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M. Laipert

2006-04-01

Full Text Available This paper deals with a design method of the analog all-pass filter designated for equalization of the group delay frequency response of the analog filter. This method is based on usage of evolutionary algorithm, the Differential Evolution algorithm in particular. We are able to design such equalizers to be obtained equal-ripple group delay frequency response in the pass-band of the low-pass filter. The procedure works automatically without an input estimation. The method is presented on solving practical examples.

Future Land-Use Changes and the Potential for Novelty in Ecosystems of the United States

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Sebastian Martinuzzi; Gregorio I. Gavier-Pizarro; Ariel E. Lugo; Volker C. Radeloff

2015-01-01

Rapid global changes due to changing land use, climate, and non-native species are altering environmental conditions, resulting in more novel communities with unprecedented species combinations. Understanding how future anthropogenic changes may affect novelty in ecosystems is important to advance environmental management and ecological research in the Anthropocene....

Development of a population of cancer cells: Observation and modeling by a Mixed Spatial Evolutionary Games approach.

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Świerniak, Andrzej; Krześlak, Michał; Student, Sebastian; Rzeszowska-Wolny, Joanna

2016-09-21

Living cells, like whole living organisms during evolution, communicate with their neighbors, interact with the environment, divide, change their phenotypes, and eventually die. The development of specific ways of communication (through signaling molecules and receptors) allows some cellular subpopulations to survive better, to coordinate their physiological status, and during embryonal development to create tissues and organs or in some conditions to become tumors. Populations of cells cultured in vitro interact similarly, also competing for space and nutrients and stimulating each other to better survive or to die. The results of these intercellular interactions of different types seem to be good examples of biological evolutionary games, and have been the subjects of simulations by the methods of evolutionary game theory where individual cells are treated as players. Here we present examples of intercellular contacts in a population of living human cancer HeLa cells cultured in vitro and propose an evolutionary game theory approach to model the development of such populations. We propose a new technique termed Mixed Spatial Evolutionary Games (MSEG) which are played on multiple lattices corresponding to the possible cellular phenotypes which gives the possibility of simulating and investigating the effects of heterogeneity at the cellular level in addition to the population level. Analyses performed with MSEG suggested different ways in which cellular populations develop in the case of cells communicating directly and through factors released to the environment. Copyright © 2016 Elsevier Ltd. All rights reserved.

Role of Genomic Typing in Taxonomy, Evolutionary Genetics, and Microbial Epidemiology

Science.gov (United States)

van Belkum, Alex; Struelens, Marc; de Visser, Arjan; Verbrugh, Henri; Tibayrenc, Michel

2001-01-01

Currently, genetic typing of microorganisms is widely used in several major fields of microbiological research. Taxonomy, research aimed at elucidation of evolutionary dynamics or phylogenetic relationships, population genetics of microorganisms, and microbial epidemiology all rely on genetic typing data for discrimination between genotypes. Apart from being an essential component of these fundamental sciences, microbial typing clearly affects several areas of applied microbiogical research. The epidemiological investigation of outbreaks of infectious diseases and the measurement of genetic diversity in relation to relevant biological properties such as pathogenicity, drug resistance, and biodegradation capacities are obvious examples. The diversity among nucleic acid molecules provides the basic information for all fields described above. However, researchers in various disciplines tend to use different vocabularies, a wide variety of different experimental methods to monitor genetic variation, and sometimes widely differing modes of data processing and interpretation. The aim of the present review is to summarize the technological and fundamental concepts used in microbial taxonomy, evolutionary genetics, and epidemiology. Information on the nomenclature used in the different fields of research is provided, descriptions of the diverse genetic typing procedures are presented, and examples of both conceptual and technological research developments for Escherichia coli are included. Recommendations for unification of the different fields through standardization of laboratory techniques are made. PMID:11432813

Evidence of repeated and independent saltational evolution in a peculiar genus of sphinx moths (Proserpinus: Sphingidae.

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Daniel Rubinoff

Full Text Available Saltational evolution in which a particular lineage undergoes relatively rapid, significant, and unparalleled change as compared with its closest relatives is rarely invoked as an alternative model to the dominant paradigm of gradualistic evolution. Identifying saltational events is an important first-step in assessing the importance of this discontinuous model in generating evolutionary novelty. We offer evidence for three independent instances of saltational evolution in a charismatic moth genus with only eight species.Maximum parsimony, maximum likelihood and Bayesian search criteria offered congruent, well supported phylogenies based on 1,965 base pairs of DNA sequence using the mitochondrial gene cytochrome oxidase subunit I, and the nuclear genes elongation factor-1 alpha and wingless. Using a comparative methods approach, we examined three taxa exhibiting novelty in the form of Batesian mimicry, host plant shift, and dramatic physiological differences in light of the phylogenetic data. All three traits appear to have evolved relatively rapidly and independently in three different species of Proserpinus. Each saltational species exhibits a markedly different and discrete example of discontinuous trait evolution while remaining canalized for other typical traits shared by the rest of the genus. All three saltational taxa show insignificantly different levels of overall genetic change as compared with their congeners, implying that their divergence is targeted to particular traits and not genome-wide.Such rapid evolution of novel traits in individual species suggests that the pace of evolution can be quick, dramatic, and isolated--even on the species level. These results may be applicable to other groups in which specific taxa have generated pronounced evolutionary novelty. Genetic mechanisms and methods for assessing such relatively rapid changes are postulated.

Evidence of repeated and independent saltational evolution in a peculiar genus of sphinx moths (Proserpinus: Sphingidae).

Science.gov (United States)

Rubinoff, Daniel; Le Roux, Johannes J

2008-01-01

Saltational evolution in which a particular lineage undergoes relatively rapid, significant, and unparalleled change as compared with its closest relatives is rarely invoked as an alternative model to the dominant paradigm of gradualistic evolution. Identifying saltational events is an important first-step in assessing the importance of this discontinuous model in generating evolutionary novelty. We offer evidence for three independent instances of saltational evolution in a charismatic moth genus with only eight species. Maximum parsimony, maximum likelihood and Bayesian search criteria offered congruent, well supported phylogenies based on 1,965 base pairs of DNA sequence using the mitochondrial gene cytochrome oxidase subunit I, and the nuclear genes elongation factor-1 alpha and wingless. Using a comparative methods approach, we examined three taxa exhibiting novelty in the form of Batesian mimicry, host plant shift, and dramatic physiological differences in light of the phylogenetic data. All three traits appear to have evolved relatively rapidly and independently in three different species of Proserpinus. Each saltational species exhibits a markedly different and discrete example of discontinuous trait evolution while remaining canalized for other typical traits shared by the rest of the genus. All three saltational taxa show insignificantly different levels of overall genetic change as compared with their congeners, implying that their divergence is targeted to particular traits and not genome-wide. Such rapid evolution of novel traits in individual species suggests that the pace of evolution can be quick, dramatic, and isolated--even on the species level. These results may be applicable to other groups in which specific taxa have generated pronounced evolutionary novelty. Genetic mechanisms and methods for assessing such relatively rapid changes are postulated.

Bidirectional QoS support for novelty detection applications based on hierarchical wireless sensor network model

Science.gov (United States)

Edwards, Mark; Hu, Fei; Kumar, Sunil

2004-10-01

The research on the Novelty Detection System (NDS) (called as VENUS) at the authors' universities has generated exciting results. For example, we can detect an abnormal behavior (such as cars thefts from the parking lot) from a series of video frames based on the cognitively motivated theory of habituation. In this paper, we would like to describe the implementation strategies of lower layer protocols for using large-scale Wireless Sensor Networks (WSN) to NDS with Quality-of-Service (QoS) support. Wireless data collection framework, consisting of small and low-power sensor nodes, provides an alternative mechanism to observe the physical world, by using various types of sensing capabilities that include images (and even videos using Panoptos), sound and basic physical measurements such as temperature. We do not want to lose any 'data query command' packets (in the downstream direction: sink-to-sensors) or have any bit-errors in them since they are so important to the whole sensor network. In the upstream direction (sensors-to-sink), we may tolerate the loss of some sensing data packets. But the 'interested' sensing flow should be assigned a higher priority in terms of multi-hop path choice, network bandwidth allocation, and sensing data packet generation frequency (we hope to generate more sensing data packet for that novel event in the specified network area). The focus of this paper is to investigate MAC-level Quality of Service (QoS) issue in Wireless Sensor Networks (WSN) for Novelty Detection applications. Although QoS has been widely studied in other types of networks including wired Internet, general ad hoc networks and mobile cellular networks, we argue that QoS in WSN has its own characteristics. In wired Internet, the main QoS parameters include delay, jitter and bandwidth. In mobile cellular networks, two most common QoS metrics are: handoff call dropping probability and new call blocking probability. Since the main task of WSN is to detect and report

Evolutionary Perspectives on Genetic and Environmental Risk Factors for Psychiatric Disorders.

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Keller, Matthew C

2018-05-07

Evolutionary medicine uses evolutionary theory to help elucidate why humans are vulnerable to disease and disorders. I discuss two different types of evolutionary explanations that have been used to help understand human psychiatric disorders. First, a consistent finding is that psychiatric disorders are moderately to highly heritable, and many, such as schizophrenia, are also highly disabling and appear to decrease Darwinian fitness. Models used in evolutionary genetics to understand why genetic variation exists in fitness-related traits can be used to understand why risk alleles for psychiatric disorders persist in the population. The usual explanation for species-typical adaptations-natural selection-is less useful for understanding individual differences in genetic risk to disorders. Rather, two other types of models, mutation-selection-drift and balancing selection, offer frameworks for understanding why genetic variation in risk to psychiatric (and other) disorders exists, and each makes predictions that are now testable using whole-genome data. Second, species-typical capacities to mount reactions to negative events are likely to have been crafted by natural selection to minimize fitness loss. The pain reaction to tissue damage is almost certainly such an example, but it has been argued that the capacity to experience depressive symptoms such as sadness, anhedonia, crying, and fatigue in the face of adverse life situations may have been crafted by natural selection as well. I review the rationale and strength of evidence for this hypothesis. Evolutionary hypotheses of psychiatric disorders are important not only for offering explanations for why psychiatric disorders exist, but also for generating new, testable hypotheses and understanding how best to design studies and analyze data.

Bigger Is Fitter? Quantitative Genetic Decomposition of Selection Reveals an Adaptive Evolutionary Decline of Body Mass in a Wild Rodent Population.

OpenAIRE

Timothée Bonnet; Peter Wandeler; Glauco Camenisch; Erik Postma

2017-01-01

In natural populations, quantitative trait dynamics often do not appear to follow evolutionary predictions: Despite abundant examples of natural selection acting on heritable traits, conclusive evidence for contemporary adaptive evolution remains rare for wild vertebrate populations, and phenotypic stasis seems to be the norm. This so-called ‘stasis paradox’ highlights our inability to predict evolutionary change, which is especially concerning within the context of rapid anthropogenic enviro...

Ecological theatre and the evolutionary game: how environmental and demographic factors determine payoffs in evolutionary games.

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Argasinski, K; Broom, M

2013-10-01

In the standard approach to evolutionary games and replicator dynamics, differences in fitness can be interpreted as an excess from the mean Malthusian growth rate in the population. In the underlying reasoning, related to an analysis of "costs" and "benefits", there is a silent assumption that fitness can be described in some type of units. However, in most cases these units of measure are not explicitly specified. Then the question arises: are these theories testable? How can we measure "benefit" or "cost"? A natural language, useful for describing and justifying comparisons of strategic "cost" versus "benefits", is the terminology of demography, because the basic events that shape the outcome of natural selection are births and deaths. In this paper, we present the consequences of an explicit analysis of births and deaths in an evolutionary game theoretic framework. We will investigate different types of mortality pressures, their combinations and the possibility of trade-offs between mortality and fertility. We will show that within this new approach it is possible to model how strictly ecological factors such as density dependence and additive background fitness, which seem neutral in classical theory, can affect the outcomes of the game. We consider the example of the Hawk-Dove game, and show that when reformulated in terms of our new approach new details and new biological predictions are produced.

MOST IMPORTANT NOVELTIES IN BANKRUPTCY ACT OF 2015

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Jasnica Garašić

2017-01-01

Full Text Available This paper gives the analysis of the most important novelties that the new Bankruptcy Act of 2015 brought into Croatian bankruptcy law. The author points at many contradictory, imprecise and defective provisions of the new Bankruptcy Act, especially provisions regarding a pre-bankruptcy reason (ground, pre-bankruptcy proceedings, advance payment for the costs of bankruptcy proceedings, appointment of bankruptcy administrators (bankruptcy trustees, action to contest legal transactions of the debtor, liquidation of objects on which the right for separate satisfaction exists, bankruptcy plan, group of companies (connected companies, bankruptcy proceedings against liquidation estate and international bankruptcy. Due to numerousness of the defective legal solutions and disturbing easiness with which some of the basic principles of bankruptcy law and civil procedure law generally have been directly broken, it is necessary to prepare new legal provisions that shall change and amend the Bankruptcy Act of 2015.

Chemical evolutionary games.

Science.gov (United States)

Aristotelous, Andreas C; Durrett, Richard

2014-05-01

Inspired by the use of hybrid cellular automata in modeling cancer, we introduce a generalization of evolutionary games in which cells produce and absorb chemicals, and the chemical concentrations dictate the death rates of cells and their fitnesses. Our long term aim is to understand how the details of the interactions in a system with n species and m chemicals translate into the qualitative behavior of the system. Here, we study two simple 2×2 games with two chemicals and revisit the two and three species versions of the one chemical colicin system studied earlier by Durrett and Levin (1997). We find that in the 2×2 examples, the behavior of our new spatial model can be predicted from that of the mean field differential equation using ideas of Durrett and Levin (1994). However, in the three species colicin model, the system with diffusion does not have the coexistence which occurs in the lattices model in which sites interact with only their nearest neighbors. Copyright © 2014 Elsevier Inc. All rights reserved.

Multiparty Evolutionary Game Model in Coal Mine Safety Management and Its Application

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Rongwu Lu

2018-01-01

Full Text Available Coal mine safety management involves many interested parties and there are complex relationships between them. According to game theory, a multiparty evolutionary game model is established to analyze the selection of strategies. Then, a simplified three-party model is taken as an example to carry out detailed analysis and solution. Based on stability theory of dynamics system and phase diagram analysis, this article studies replicator dynamics of the evolutionary model to make an optimization analysis of the behaviors of those interested parties and the adjustment mechanism of safety management policies and decisions. The results show how the charge of supervision of government department and inspection of coal mine enterprise impact the efficiency of safety management and the effect of constraint measures and incentive and other measures in safety management.

EPR by AREVA. An evolutionary reactor

International Nuclear Information System (INIS)

Horstmann, Marion

2010-01-01

The EPR development goals are as follows: 1. Evolutionary design to fully capitalize on the design, construction and operating experience based on the 86 AREVA's PWR operating worldwide; 2. Enhanced Safety compared to operating PWRs: reduce core damage frequency (CDF), accommodate severe accidents with no long-term population effect, Withstand large airplane crash (APC); 3. High availability; 4. Simplified operation and maintenance; and 5. Generation cost at least 10 % lower than 1500 MWe series in operation.The design builds on the achievements of the N4 and Konvoi reactors. The main plant data are tabulated. The PWR structure is shown as an example of the stepwise improvement. Focus of the presentation is on the construction techniques, supply chain, and project delivery. (P.A.)

Effects of a selectively bred novelty-seeking phenotype on the motivation to take cocaine in male and female rats

Directory of Open Access Journals (Sweden)

Cummings Jennifer A

2011-03-01

Full Text Available Abstract Background Gender and enhanced novelty reactivity can predispose certain individuals to drug abuse. Previous research in male and female rats selectively bred for high or low locomotor reactivity to novelty found that bred High Responders (bHRs acquire cocaine self-administration more rapidly than bred Low Responders (bLRs and that bHR females in particular self-administered more cocaine than the other groups. The experiments presented here aimed to determine whether an individual's sex and behavioral phenotype interact to affect motivation to take cocaine. Methods We examined motivation for taking cocaine in two experiments using a range of doses on a progressive ratio (PR schedule of responding in bHR or bLR males and females. Additionally, we included a measure of continuing to respond in the absence of reinforcement, a feature of addiction that has been recently incorporated into tests of animal models on the basis of the criteria for substance use disorder in the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition. Statistical analyses were performed using PASW Statistics 18.0 software. Data were analyzed using repeated-measures analysis of variance followed by a Bonferroni correction post hoc test when applicable. Results We found sex differences as well as effects of novelty reactivity on the motivation to self-administer cocaine. Specifically, females demonstrated higher breaking points on the PR schedule compared with males, regardless of phenotype, and bHR males and females exhibited higher motivation than bLR animals at a number of the doses studied. Conclusions An individual's sex continues to be a predisposing factor with respect to drug abuse liability and can be compounded by additional individual differences such as reactivity to novelty.

The Cyborg Astrobiologist: testing a novelty detection algorithm on two mobile exploration systems at Rivas Vaciamadrid in Spain and at the Mars Desert Research Station in Utah

Science.gov (United States)

McGuire, P. C.; Gross, C.; Wendt, L.; Bonnici, A.; Souza-Egipsy, V.; Ormö, J.; Díaz-Martínez, E.; Foing, B. H.; Bose, R.; Walter, S.; Oesker, M.; Ontrup, J.; Haschke, R.; Ritter, H.

2010-01-01

In previous work, a platform was developed for testing computer-vision algorithms for robotic planetary exploration. This platform consisted of a digital video camera connected to a wearable computer for real-time processing of images at geological and astrobiological field sites. The real-time processing included image segmentation and the generation of interest points based upon uncommonness in the segmentation maps. Also in previous work, this platform for testing computer-vision algorithms has been ported to a more ergonomic alternative platform, consisting of a phone camera connected via the Global System for Mobile Communications (GSM) network to a remote-server computer. The wearable-computer platform has been tested at geological and astrobiological field sites in Spain (Rivas Vaciamadrid and Riba de Santiuste), and the phone camera has been tested at a geological field site in Malta. In this work, we (i) apply a Hopfield neural-network algorithm for novelty detection based upon colour, (ii) integrate a field-capable digital microscope on the wearable computer platform, (iii) test this novelty detection with the digital microscope at Rivas Vaciamadrid, (iv) develop a Bluetooth communication mode for the phone-camera platform, in order to allow access to a mobile processing computer at the field sites, and (v) test the novelty detection on the Bluetooth-enabled phone camera connected to a netbook computer at the Mars Desert Research Station in Utah. This systems engineering and field testing have together allowed us to develop a real-time computer-vision system that is capable, for example, of identifying lichens as novel within a series of images acquired in semi-arid desert environments. We acquired sequences of images of geologic outcrops in Utah and Spain consisting of various rock types and colours to test this algorithm. The algorithm robustly recognized previously observed units by their colour, while requiring only a single image or a few images to

Evolutionary Demography

DEFF Research Database (Denmark)

Levitis, Daniel

2015-01-01

of biological and cultural evolution. Demographic variation within and among human populations is influenced by our biology, and therefore by natural selection and our evolutionary background. Demographic methods are necessary for studying populations of other species, and for quantifying evolutionary fitness......Demography is the quantitative study of population processes, while evolution is a population process that influences all aspects of biological organisms, including their demography. Demographic traits common to all human populations are the products of biological evolution or the interaction...

Proteomics in evolutionary ecology.

Science.gov (United States)

Baer, B; Millar, A H

2016-03-01

Evolutionary ecologists are traditionally gene-focused, as genes propagate phenotypic traits across generations and mutations and recombination in the DNA generate genetic diversity required for evolutionary processes. As a consequence, the inheritance of changed DNA provides a molecular explanation for the functional changes associated with natural selection. A direct focus on proteins on the other hand, the actual molecular agents responsible for the expression of a phenotypic trait, receives far less interest from ecologists and evolutionary biologists. This is partially due to the central dogma of molecular biology that appears to define proteins as the 'dead-end of molecular information flow' as well as technical limitations in identifying and studying proteins and their diversity in the field and in many of the more exotic genera often favored in ecological studies. Here we provide an overview of a newly forming field of research that we refer to as 'Evolutionary Proteomics'. We point out that the origins of cellular function are related to the properties of polypeptide and RNA and their interactions with the environment, rather than DNA descent, and that the critical role of horizontal gene transfer in evolution is more about coopting new proteins to impact cellular processes than it is about modifying gene function. Furthermore, post-transcriptional and post-translational processes generate a remarkable diversity of mature proteins from a single gene, and the properties of these mature proteins can also influence inheritance through genetic and perhaps epigenetic mechanisms. The influence of post-transcriptional diversification on evolutionary processes could provide a novel mechanistic underpinning for elements of rapid, directed evolutionary changes and adaptations as observed for a variety of evolutionary processes. Modern state-of the art technologies based on mass spectrometry are now available to identify and quantify peptides, proteins, protein

Species packing in eco-evolutionary models of seasonally fluctuating environments.

Science.gov (United States)

Kremer, Colin T; Klausmeier, Christopher A

2017-09-01

As ecology and evolution become ever more entwined, many areas of ecological theory are being re-examined. Eco-evolutionary analyses of classic coexistence mechanisms are yielding new insights into the structure and stability of communities. We examine fluctuation-dependent coexistence models, identifying communities that are both ecologically and evolutionarily stable. Members of these communities possess distinct environmental preferences, revealing widespread patterns of limiting similarity. This regularity leads to consistent changes in the structure of communities across fluctuation regimes. However, at high amplitudes, subtle differences in the form of fluctuations dramatically affect the collapse of communities. We also show that identical fluctuations can support multiple evolutionarily stable communities - a novel example of alternative stable states within eco-evolutionary systems. Consequently, the configuration of communities will depend on historical contingencies, including details of the adaptive process. Integrating evolution into the study of coexistence offers new insights, while enriching our understanding of ecology. © 2017 John Wiley & Sons Ltd/CNRS.

A Survey on Evolutionary Algorithm Based Hybrid Intelligence in Bioinformatics

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Shan Li

2014-01-01

Full Text Available With the rapid advance in genomics, proteomics, metabolomics, and other types of omics technologies during the past decades, a tremendous amount of data related to molecular biology has been produced. It is becoming a big challenge for the bioinformatists to analyze and interpret these data with conventional intelligent techniques, for example, support vector machines. Recently, the hybrid intelligent methods, which integrate several standard intelligent approaches, are becoming more and more popular due to their robustness and efficiency. Specifically, the hybrid intelligent approaches based on evolutionary algorithms (EAs are widely used in various fields due to the efficiency and robustness of EAs. In this review, we give an introduction about the applications of hybrid intelligent methods, in particular those based on evolutionary algorithm, in bioinformatics. In particular, we focus on their applications to three common problems that arise in bioinformatics, that is, feature selection, parameter estimation, and reconstruction of biological networks.

Evolutionary and developmental modules.

Science.gov (United States)

Lacquaniti, Francesco; Ivanenko, Yuri P; d'Avella, Andrea; Zelik, Karl E; Zago, Myrka

2013-01-01

The identification of biological modules at the systems level often follows top-down decomposition of a task goal, or bottom-up decomposition of multidimensional data arrays into basic elements or patterns representing shared features. These approaches traditionally have been applied to mature, fully developed systems. Here we review some results from two other perspectives on modularity, namely the developmental and evolutionary perspective. There is growing evidence that modular units of development were highly preserved and recombined during evolution. We first consider a few examples of modules well identifiable from morphology. Next we consider the more difficult issue of identifying functional developmental modules. We dwell especially on modular control of locomotion to argue that the building blocks used to construct different locomotor behaviors are similar across several animal species, presumably related to ancestral neural networks of command. A recurrent theme from comparative studies is that the developmental addition of new premotor modules underlies the postnatal acquisition and refinement of several different motor behaviors in vertebrates.

Energy law novelties

International Nuclear Information System (INIS)

Butnaru, Paula

2004-01-01

Energy Law no. 318/2003 has been worked out in compliance with the EU Electricity Directive based on the following principles and objectives: - clearly defining the positions and roles of various institutional entities and structures; - introducing the competitions in energy generation and supply; - creation and functioning of electricity competitive markets; - right of certain consumers to buy electricity directly from the producers; - direct, fair and regulated access to electrical network of all the participants in the electricity market; - generators, distributors and consumers; - achieving the activities in the field under reliable conditions and at the quality standards for optimally using the primary energy resources by observing the environmental protection norms in force; - promoting, in a balanced manner, the interests of the National Power System based on the European regulations and requirements on optimal and efficient resources use by observing the environmental criteria and norms; - ensuring the sustainable development of the national economy; - diversifying the primary energy resources basis; - transparency of electricity tariffs, prices and taxes; - creating the security stocks of needed fuels for electricity and heat co-generation; - ensuring the interconnected operation of the NPS with the energy systems in the neighboring countries and with the ones in the UCTE; - promoting the use of renewable energy sources. Among the novelties brought by this Law by the definitions given to the terms used it is worth mentioning: - Access to the public electricity network; - Energy capacity; - Passageway of the electric line; - Natural monopoly in the energy field; - Electricity market operator; - Distribution system operator; - Transmission system operator; -Merit order (i.e the order in which an electricity producer is taken into consideration according to the price offered to cover the NPS electricity demand); - Electricity market; - Rehabilitation

Analysis of the first- and second-generation Raving Dragon Novelty Bath Salts containing methylone and pentedrone.

Science.gov (United States)

Poklis, Justin L; Wolf, Carl E; ElJordi, Omar I; Liu, Kai; Zhang, Shijun; Poklis, Alphonse

2015-01-01

In recent years, a large number of designer drugs sold as "Bath Salts" have appeared on the market. In July of 2011, Raving Dragon Novelty Bath Salts was obtained over the Internet. This product became unavailable in October of that year coinciding with the DEA issuing a temporarily schedule of mephedrone, methylone, and MDPV. Four months later in February of 2012, a new product was released from the same company under the new name Raving Dragon Voodoo Dust. The contents of both products were identified using spectroscopy methods: nuclear magnetic resonance, infrared, UV-visible, tandem mass spectrometry, and high-resolution time-of-flight mass spectrometry. It was determined that Raving Dragon Novelty Bath Salts contained methylone. The replacement product Raving Dragon Voodoo Dust contained the unscheduled drug pentedrone. The Raving Dragon brand of products illustrates the rapid change of ingredients in these products to circumvent laws restricting availability, distribution, and use. © 2014 American Academy of Forensic Sciences.

Novelty-Sensitive Dopaminergic Neurons in the Human Substantia Nigra Predict Success of Declarative Memory Formation.

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Kamiński, Jan; Mamelak, Adam N; Birch, Kurtis; Mosher, Clayton P; Tagliati, Michele; Rutishauser, Ueli

2018-04-12

The encoding of information into long-term declarative memory is facilitated by dopamine. This process depends on hippocampal novelty signals, but it remains unknown how midbrain dopaminergic neurons are modulated by declarative-memory-based information. We recorded individual substantia nigra (SN) neurons and cortical field potentials in human patients performing a recognition memory task. We found that 25% of SN neurons were modulated by stimulus novelty. Extracellular waveform shape and anatomical location indicated that these memory-selective neurons were putatively dopaminergic. The responses of memory-selective neurons appeared 527 ms after stimulus onset, changed after a single trial, and were indicative of recognition accuracy. SN neurons phase locked to frontal cortical theta-frequency oscillations, and the extent of this coordination predicted successful memory formation. These data reveal that dopaminergic neurons in the human SN are modulated by memory signals and demonstrate a progression of information flow in the hippocampal-basal ganglia-frontal cortex loop for memory encoding. Copyright © 2018 The Author(s). Published by Elsevier Ltd.. All rights reserved.

Evolutionary Cell Biology of Proteins from Protists to Humans and Plants.

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Plattner, Helmut

2018-03-01

During evolution, the cell as a fine-tuned machine had to undergo permanent adjustments to match changes in its environment, while "closed for repair work" was not possible. Evolution from protists (protozoa and unicellular algae) to multicellular organisms may have occurred in basically two lineages, Unikonta and Bikonta, culminating in mammals and angiosperms (flowering plants), respectively. Unicellular models for unikont evolution are myxamoebae (Dictyostelium) and increasingly also choanoflagellates, whereas for bikonts, ciliates are preferred models. Information accumulating from combined molecular database search and experimental verification allows new insights into evolutionary diversification and maintenance of genes/proteins from protozoa on, eventually with orthologs in bacteria. However, proteins have rarely been followed up systematically for maintenance or change of function or intracellular localization, acquirement of new domains, partial deletion (e.g. of subunits), and refunctionalization, etc. These aspects are discussed in this review, envisaging "evolutionary cell biology." Protozoan heritage is found for most important cellular structures and functions up to humans and flowering plants. Examples discussed include refunctionalization of voltage-dependent Ca 2+ channels in cilia and replacement by other types during evolution. Altogether components serving Ca 2+ signaling are very flexible throughout evolution, calmodulin being a most conservative example, in contrast to calcineurin whose catalytic subunit is lost in plants, whereas both subunits are maintained up to mammals for complex functions (immune defense and learning). Domain structure of R-type SNAREs differs in mono- and bikonta, as do Ca 2+ -dependent protein kinases. Unprecedented selective expansion of the subunit a which connects multimeric base piece and head parts (V0, V1) of H + -ATPase/pump may well reflect the intriguing vesicle trafficking system in ciliates, specifically in

Life on a block of limestone: Evolutionary, ecological and geological dynamics of isolated malacofaunas on tropical karst

NARCIS (Netherlands)

Schilthuizen, M.

2011-01-01

The karst formations of southeast Asia are a wonderful evolutionary and ecological experiment, and a sad example of observable extinction (Clements et al., 2006). In this paper, I shall focus on those in Malaysia and, in particular, on the land snail faunas that they support.

Video of World Festivals as Novelties in Teaching Description Writing Using a Genre-Based Approach

Science.gov (United States)

Rajagopalan, Uma Maheswari

2017-01-01

In order to motivate ESL students and engage them in different tasks effectively, it is necessary to make the tasks novel to the students. As one possible way of introducing novelty in the course, films could be used advantageously. In this study, a writing course integrated with videos of movies and cultural festival of different regions of the…

Rule concerning sanitary protection against ionizing radiations: novelties

International Nuclear Information System (INIS)

Bercedo, A.; Carmena, P.; Prieto, J. A.; Rubio, G.; Sollet, E.; Sustacha, D.

2002-01-01

Last July the a new legal Rule concerning Sanitary Protection against Ionising Radiation was published, as a transposition of the EU Directive about the Basic Norms related to the sanitary protection of workers and population against the risks resultant of the ionising radiation. The origin of this legislation goes back to the revision of the protection doctrine by the International Commission of Radiation Protection (ICRP) en the year 1990. El scope of the revised Rule is the regulation of the protection of population and workers against ionising radiation, the establishment of the national protection system with its exposition and dose limits and the correspondent penalty regime. It also modifies the maximum radiation dose limits and reinforces the application of the optimisation principle in the use of ionising radiation. In this article, the novelties introduced by the new Rule are commented in detail, ordered by the Titles I to IX in which the Rule is divided. (Author)

Evolutionary novelty versus exaptation: oral kinematics in feeding versus climbing in the waterfall-climbing Hawaiian Goby Sicyopterus stimpsoni.

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Joshua A Cullen

behaviors. Such comparisons can provide insight into the evolutionary mechanisms facilitating exploitation of extreme habitats.

Evolutionary novelty versus exaptation: oral kinematics in feeding versus climbing in the waterfall-climbing Hawaiian Goby Sicyopterus stimpsoni.

Science.gov (United States)

Cullen, Joshua A; Maie, Takashi; Schoenfuss, Heiko L; Blob, Richard W

2013-01-01

comparisons can provide insight into the evolutionary mechanisms facilitating exploitation of extreme habitats.

Deep Rationality: The Evolutionary Economics of Decision Making.

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Kenrick, Douglas T; Griskevicius, Vladas; Sundie, Jill M; Li, Norman P; Li, Yexin Jessica; Neuberg, Steven L

2009-10-01

What is a "rational" decision? Economists traditionally viewed rationality as maximizing expected satisfaction. This view has been useful in modeling basic microeconomic concepts, but falls short in accounting for many everyday human decisions. It leaves unanswered why some things reliably make people more satisfied than others, and why people frequently act to make others happy at a cost to themselves. Drawing on an evolutionary perspective, we propose that people make decisions according to a set of principles that may not appear to make sense at the superficial level, but that demonstrate rationality at a deeper evolutionary level. By this, we mean that people use adaptive domain-specific decision-rules that, on average, would have resulted in fitness benefits. Using this framework, we re-examine several economic principles. We suggest that traditional psychological functions governing risk aversion, discounting of future benefits, and budget allocations to multiple goods, for example, vary in predictable ways as a function of the underlying motive of the decision-maker and individual differences linked to evolved life-history strategies. A deep rationality framework not only helps explain why people make the decisions they do, but also inspires multiple directions for future research.

Attractive evolutionary equilibria

OpenAIRE

Roorda, Berend; Joosten, Reinoud

2011-01-01

We present attractiveness, a refinement criterion for evolutionary equilibria. Equilibria surviving this criterion are robust to small perturbations of the underlying payoff system or the dynamics at hand. Furthermore, certain attractive equilibria are equivalent to others for certain evolutionary dynamics. For instance, each attractive evolutionarily stable strategy is an attractive evolutionarily stable equilibrium for certain barycentric ray-projection dynamics, and vice versa.

Animal evolution: stiff or squishy notochord origins?

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Hejnol, Andreas; Lowe, Christopher J

2014-12-01

The notochord is considered an evolutionary novelty and one of the defining characters of chordates. A new study of an annelid challenges this view and proposes an earlier evolutionary origin in the most recent common ancestor of chordates and annelids. Copyright © 2014 Elsevier Ltd. All rights reserved.

Strategies for measuring evolutionary conservation of RNA secondary structures

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Hofacker Ivo L

2008-02-01

Full Text Available Abstract Background Evolutionary conservation of RNA secondary structure is a typical feature of many functional non-coding RNAs. Since almost all of the available methods used for prediction and annotation of non-coding RNA genes rely on this evolutionary signature, accurate measures for structural conservation are essential. Results We systematically assessed the ability of various measures to detect conserved RNA structures in multiple sequence alignments. We tested three existing and eight novel strategies that are based on metrics of folding energies, metrics of single optimal structure predictions, and metrics of structure ensembles. We find that the folding energy based SCI score used in the RNAz program and a simple base-pair distance metric are by far the most accurate. The use of more complex metrics like for example tree editing does not improve performance. A variant of the SCI performed particularly well on highly conserved alignments and is thus a viable alternative when only little evolutionary information is available. Surprisingly, ensemble based methods that, in principle, could benefit from the additional information contained in sub-optimal structures, perform particularly poorly. As a general trend, we observed that methods that include a consensus structure prediction outperformed equivalent methods that only consider pairwise comparisons. Conclusion Structural conservation can be measured accurately with relatively simple and intuitive metrics. They have the potential to form the basis of future RNA gene finders, that face new challenges like finding lineage specific structures or detecting mis-aligned sequences.

Evolutionary Control of Infectious Disease: Prospects for Vectorborne and Waterborne Pathogens

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Paul W Ewald

1998-09-01

Full Text Available Evolutionary theory may contribute to practical solutions for control of disease by identifying interventions that may cause pathogens to evolve to reduced virulence. Theory predicts, for example, that pathogens transmitted by water or arthropod vectors should evolve to relatively high levels of virulence because such pathogens can gain the evolutionary benefits of relatively high levels of host exploitation while paying little price from host illness. The entrance of Vibrio cholerae into South America in 1991 has generated a natural experiment that allows testing of this idea by determining whether geographic and temporal variations in toxigenicity correspond to variation in the potential for waterborne transmission. Preliminary studies show such correspondences: toxigenicity is negatively associated with access to uncontaminated water in Brazil; and in Chile, where the potential for waterborne transmission is particularly low, toxigenicity of strains declined between 1991 and 1998. In theory vector-proofing of houses should be similarly associated with benignity of vectorborne pathogens, such as the agents of dengue, malaria, and Chagas' disease. These preliminary studies draw attention to the need for definitive prospective experiments to determine whether interventions such as provisioning of uncontaminated water and vector-proofing of houses cause evolutionary reductions in virulence

Sex-dependent novelty response in neurexin-1α mutant mice.

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Marijke C Laarakker

Full Text Available Neurexin-1 alpha (NRXN1α belongs to the family of cell adhesion molecules (CAMs, which are involved in the formation of neuronal networks and synapses. NRXN1α gene mutations have been identified in neuropsychiatric diseases including Schizophrenia (SCZ and Autism Spectrum Disorder (ASD. In order to get a better understanding of the pleiotropic behavioral manifestations caused by NRXN1α gene mutations, we performed a behavioral study of Nrxn1α heterozygous knock-out (+/- mice and observed increased responsiveness to novelty and accelerated habituation to novel environments compared to wild type (+/+ litter-mates. However, this effect was mainly observed in male mice, strongly suggesting that gender-specific mechanisms play an important role in Nrxn1α-induced phenotypes.

Algorithmic Mechanism Design of Evolutionary Computation.

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Pei, Yan

2015-01-01

We consider algorithmic design, enhancement, and improvement of evolutionary computation as a mechanism design problem. All individuals or several groups of individuals can be considered as self-interested agents. The individuals in evolutionary computation can manipulate parameter settings and operations by satisfying their own preferences, which are defined by an evolutionary computation algorithm designer, rather than by following a fixed algorithm rule. Evolutionary computation algorithm designers or self-adaptive methods should construct proper rules and mechanisms for all agents (individuals) to conduct their evolution behaviour correctly in order to definitely achieve the desired and preset objective(s). As a case study, we propose a formal framework on parameter setting, strategy selection, and algorithmic design of evolutionary computation by considering the Nash strategy equilibrium of a mechanism design in the search process. The evaluation results present the efficiency of the framework. This primary principle can be implemented in any evolutionary computation algorithm that needs to consider strategy selection issues in its optimization process. The final objective of our work is to solve evolutionary computation design as an algorithmic mechanism design problem and establish its fundamental aspect by taking this perspective. This paper is the first step towards achieving this objective by implementing a strategy equilibrium solution (such as Nash equilibrium) in evolutionary computation algorithm.

The role of novelty seeking as a predictor of substance use disorder outcomes in early adulthood.

Science.gov (United States)

Foulds, James A; Boden, Joseph M; Newton-Howes, Giles M; Mulder, Roger T; Horwood, L John

2017-09-01

There has been a great deal of evidence showing that high novelty seeking (NS) is a risk factor for the development of substance use disorders (SUDs). However, the possible causal role of NS in SUDs is unconfirmed. The aim of this study was to examine the associations between NS at age 16 and SUDs from ages 18 to 35 years, net of a series of covariate factors. Longitudinal study of a birth cohort. Christchurch, New Zealand. General community sample with sample sizes ranging from n = 1011 (age 21) to n = 962 (age 35). The Composite International Diagnostic Interview was used to derive DSM-IV diagnoses of alcohol, nicotine, cannabis and other illicit SUDs at four time intervals from ages 18 to 35. NS was measured at age 16 using the Tridimensional Personality Questionnaire. An increase in NS was associated with increases in the prevalence of all four SUDs at age 18-35. Following adjustment for a broad range of covariate factors, estimated effect sizes (odds ratios) were reducing in magnitude, but remained moderate to large. Adjusted odds ratios of SUDs for the highest NS quartile compared to with the lowest were 2.0 [95% confidence interval (CI) = 1.5, 2.7] for alcohol; 1.8 (95% CI = 1.3, 2.7) for nicotine; 3.6 (95% CI = 2.4, 5.6) for cannabis and 5.1 (95% CI = 2.9, 9.2) for other illicit substances. The association between high novelty seeking and substance use disorders is not explained by common underlying individual factors and environmental exposures. This is consistent with the view that novelty seeking may play a causal role in the development of substance use disorders. © 2017 Society for the Study of Addiction.

Evolutionary Explanations of Eating Disorders

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Igor Kardum

2008-12-01

Full Text Available This article reviews several most important evolutionary mechanisms that underlie eating disorders. The first part clarifies evolutionary foundations of mental disorders and various mechanisms leading to their development. In the second part selective pressures and evolved adaptations causing contemporary epidemic of obesity as well as differences in dietary regimes and life-style between modern humans and their ancestors are described. Concerning eating disorders, a number of current evolutionary explanations of anorexia nervosa are presented together with their main weaknesses. Evolutionary explanations of eating disorders based on the reproductive suppression hypothesis and its variants derived from kin selection theory and the model of parental manipulation were elaborated. The sexual competition hypothesis of eating disorder, adapted to flee famine hypothesis as well as explanation based on the concept of social attention holding power and the need to belonging were also explained. The importance of evolutionary theory in modern conceptualization and research of eating disorders is emphasized.

The citation field of evolutionary economics

NARCIS (Netherlands)

Dolfsma, Wilfred; Leydesdorff, Loet

2010-01-01

Evolutionary economics has developed into an academic field of its own, institutionalized around, amongst others, the Journal of Evolutionary Economics (JEE). This paper analyzes the way and extent to which evolutionary economics has become an interdisciplinary journal, as its aim was: a journal

Female novelty and the courtship behavior of male guinea pigs (Cavia porcellus

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Cohn D.W.H.

2004-01-01

Full Text Available In several rodent species, an increase or recovery of sexual behavior can be observed when sexually satiated males are placed in contact with a novel mate. In order to assess the influence of female novelty on the courtship behavior of guinea pigs (Cavia porcellus, four adult males were observed during four daily 15-min sessions while interacting with the same pregnant female (same-female sessions. A new female was presented during the fifth session (switched-female session. The duration of behavioral categories was obtained from videotape records using an observational software. From the first to the second session, all males decreased the time allocated to investigating (sniffing and licking, following, and mounting the female, and that response did not recover by the end of the same-female sessions. No similar decreasing tendencies were detected in the circling or rumba categories. A marked increase of investigating occurred in all males from the last same-female session (8.1, 11.9, 15.1 and 17.3 percent session time to the switched-female one (16.4, 18.4, 37.1 and 28.9 percent session time, respectively. Increases in following and circling were recorded in three of four males, and full-blown recovery of mounting in one male. No consistent changes in the females' responses to males (following or attacking were observed throughout testing. These results are consistent with the hypothesis that guinea pig males recognize individual females and that courtship responses may suffer a habituation/recovery process controlled by mate novelty.

Towards a mechanistic foundation of evolutionary theory.

Science.gov (United States)

Doebeli, Michael; Ispolatov, Yaroslav; Simon, Burt

2017-02-15

Most evolutionary thinking is based on the notion of fitness and related ideas such as fitness landscapes and evolutionary optima. Nevertheless, it is often unclear what fitness actually is, and its meaning often depends on the context. Here we argue that fitness should not be a basal ingredient in verbal or mathematical descriptions of evolution. Instead, we propose that evolutionary birth-death processes, in which individuals give birth and die at ever-changing rates, should be the basis of evolutionary theory, because such processes capture the fundamental events that generate evolutionary dynamics. In evolutionary birth-death processes, fitness is at best a derived quantity, and owing to the potential complexity of such processes, there is no guarantee that there is a simple scalar, such as fitness, that would describe long-term evolutionary outcomes. We discuss how evolutionary birth-death processes can provide useful perspectives on a number of central issues in evolution.

Evolutionary thinking: "A conversation with Carter Phipps about the role of evolutionary thinking in modern culture".

Science.gov (United States)

Hunt, Tam

2014-12-01

Evolution as an idea has a lengthy history, even though the idea of evolution is generally associated with Darwin today. Rebecca Stott provides an engaging and thoughtful overview of this history of evolutionary thinking in her 2013 book, Darwin's Ghosts: The Secret History of Evolution. Since Darwin, the debate over evolution-both how it takes place and, in a long war of words with religiously-oriented thinkers, whether it takes place-has been sustained and heated. A growing share of this debate is now devoted to examining how evolutionary thinking affects areas outside of biology. How do our lives change when we recognize that all is in flux? What can we learn about life more generally if we study change instead of stasis? Carter Phipps' book, Evolutionaries: Unlocking the Spiritual and Cultural Potential of Science's Greatest Idea, delves deep into this relatively new development. Phipps generally takes as a given the validity of the Modern Synthesis of evolutionary biology. His story takes us into, as the subtitle suggests, the spiritual and cultural implications of evolutionary thinking. Can religion and evolution be reconciled? Can evolutionary thinking lead to a new type of spirituality? Is our culture already being changed in ways that we don't realize by evolutionary thinking? These are all important questions and Phipps book is a great introduction to this discussion. Phipps is an author, journalist, and contributor to the emerging "integral" or "evolutionary" cultural movement that combines the insights of Integral Philosophy, evolutionary science, developmental psychology, and the social sciences. He has served as the Executive Editor of EnlightenNext magazine (no longer published) and more recently is the co-founder of the Institute for Cultural Evolution, a public policy think tank addressing the cultural roots of America's political challenges. What follows is an email interview with Phipps.

Where Evolutionary Psychology Meets Cognitive Neuroscience: A Précis to Evolutionary Cognitive Neuroscience1

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Austen L. Krill

2007-01-01

Full Text Available Cognitive neuroscience, the study of brain-behavior relationships, has long attempted to map the brain. The discipline is flourishing, with an increasing number of functional neuroimaging studies appearing in the scientific literature daily. Unlike biology and even psychology, the cognitive neurosciences have only recently begun to apply evolutionary meta-theory and methodological guidance. Approaching cognitive neuroscience from an evolutionary perspective allows scientists to apply biologically based theoretical guidance to their investigations and can be conducted in both humans and nonhuman animals. In fact, several investigations of this sort are underway in laboratories around the world. This paper and two new volumes (Platek, Keenan, and Shackelford [Eds.], 2007; Platek and Shackelford [Eds.], under contract represent the first formal attempts to document the burgeoning field of evolutionary cognitive neuroscience. Here, we briefly review the current state of the science of evolutionary cognitive neuroscience, the methods available to the evolutionary cognitive neuroscientist, and what we foresee as the future directions of the discipline.

Diet choice patterns in rodents depend on novelty of the diet, exercise, species, and sex.

Science.gov (United States)

Yang, Tiffany; Xu, Wei-Jie; York, Haley; Liang, Nu-Chu

2017-07-01

Prolonged consumption of a palatable, high fat (HF) diet paired with a lack of physical activity can exacerbate the development of obesity. Exercise can facilitate the maintenance of a healthy body weight, possibly though mediating changes in diet preference. Using a two-diet choice and wheel running (WR) paradigm, our laboratory previously demonstrated that WR induces HF diet avoidance with different persistency in male and female rats when HF diet and WR are introduced simultaneously. The aims of this study were to examine whether this behavior is species dependent and to what extent the novelty of the diet affects WR induced HF diet avoidance. Experiment 1 utilized male C57BL6 mice in a two-diet choice and WR paradigm. Results show that all mice preferred HF to chow diet regardless of exercise and the order in which exercise and HF diet were presented. Experiment 2A (diet novelty) utilized Sprague-Dawley rats that were first habituated to a 45% HF diet prior to the simultaneous introduction of WR and a novel high-carbohydrate, low-fat (DK) diet. All rats avoided the novel high-carbohydrate diet and neither male nor female wheel running rats exhibited reduction in HF diet intake or HF diet avoidance. After all rats were returned to a sedentary condition, female rats consumed significantly more of the DK diet than the male rats. In Experiment 2B (diet familiarity), rats remained sedentary and were re-habituated to the DK diet until intake stabilized. Subsequently, a 60% HF diet was introduced for all rats and for running rats, access to the running wheels were provided simultaneously. Consistent with our previous findings, HF diet intake and preference was significantly reduced in all wheel running rats. These data suggest that exercise induced HF diet avoidance is affected by species and the novelty of the diet. Copyright © 2017 Elsevier Inc. All rights reserved.

Essays on nonlinear evolutionary game dynamics

NARCIS (Netherlands)

Ochea, M.I.

2010-01-01

Evolutionary game theory has been viewed as an evolutionary repair of rational actor game theory in the hope that a population of boundedly rational players may attain convergence to classic rational solutions, such as the Nash Equilibrium, via some learning or evolutionary process. In this thesis

β-endorphin modulates the effect of stress on novelty-suppressed feeding

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Elizabeth T. Barfield

2013-03-01

Full Text Available Although stress is implicated in the pathophysiology of mood and anxiety disorders, not all individuals who suffer stressful life events develop psychopathology. Differential susceptibility to stress may be influenced by genetically-mediated differences in hypothalamic-pituitary-adrenal (HPA axis activity and moderation of the stress response by the opioid peptide β-endorphin (β-E. The present study investigated genetic contributions to coping behavior by examining anxious behavior of transgenic mice with varying capacities to synthesize β-E (B6.129S2-Pomctm1Low/J; regulated by insertion of a premature stop codon into one or both copies of the proopiomelanocortin gene, both under normal conditions and following 3 minutes of forced swim. Ten minutes after this stress exposure or a control manipulation, acutely food-deprived female and male transgenic mice were subjected to a novelty-suppressed feeding (NSF test, during which their interaction with an almond slice located in the center of an open field box was measured. There was an interaction between genotype and stress for latency to approach the almond and whether or not the almond was approached, such that mice with low or absent β-E displayed a stronger aversion to novelty-feeding after stress exposure than did mice with normal levels. These data provide evidence for a moderating effect of β-E on the behavioral response to stress. Genotypic differences in anxious behavior emerged when mice were stressed prior to behavioral assessment, suggesting that β-E plays a role in coping behavior. These findings indicate that genetic variability in sensitivity of the β-E system to stress may contribute, at least in part, to heritable differences in stress reactivity as well as vulnerability to stress-related psychopathology.

Evolutionary rates at codon sites may be used to align sequences and infer protein domain function

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Hazelhurst Scott

2010-03-01

Full Text Available Abstract Background Sequence alignments form part of many investigations in molecular biology, including the determination of phylogenetic relationships, the prediction of protein structure and function, and the measurement of evolutionary rates. However, to obtain meaningful results, a significant degree of sequence similarity is required to ensure that the alignments are accurate and the inferences correct. Limitations arise when sequence similarity is low, which is particularly problematic when working with fast-evolving genes, evolutionary distant taxa, genomes with nucleotide biases, and cases of convergent evolution. Results A novel approach was conceptualized to address the "low sequence similarity" alignment problem. We developed an alignment algorithm termed FIRE (Functional Inference using the Rates of Evolution, which aligns sequences using the evolutionary rate at codon sites, as measured by the dN/dS ratio, rather than nucleotide or amino acid residues. FIRE was used to test the hypotheses that evolutionary rates can be used to align sequences and that the alignments may be used to infer protein domain function. Using a range of test data, we found that aligning domains based on evolutionary rates was possible even when sequence similarity was very low (for example, antibody variable regions. Furthermore, the alignment has the potential to infer protein domain function, indicating that domains with similar functions are subject to similar evolutionary constraints. These data suggest that an evolutionary rate-based approach to sequence analysis (particularly when combined with structural data may be used to study cases of convergent evolution or when sequences have very low similarity. However, when aligning homologous gene sets with sequence similarity, FIRE did not perform as well as the best traditional alignment algorithms indicating that the conventional approach of aligning residues as opposed to evolutionary rates remains the

The role of non-genetic inheritance in evolutionary rescue: epigenetic buffering, heritable bet hedging and epigenetic traps.

Science.gov (United States)

O'Dea, Rose E; Noble, Daniel W A; Johnson, Sheri L; Hesselson, Daniel; Nakagawa, Shinichi

2016-01-01

Rapid environmental change is predicted to compromise population survival, and the resulting strong selective pressure can erode genetic variation, making evolutionary rescue unlikely. Non-genetic inheritance may provide a solution to this problem and help explain the current lack of fit between purely genetic evolutionary models and empirical data. We hypothesize that epigenetic modifications can facilitate evolutionary rescue through 'epigenetic buffering'. By facilitating the inheritance of novel phenotypic variants that are generated by environmental change-a strategy we call 'heritable bet hedging'-epigenetic modifications could maintain and increase the evolutionary potential of a population. This process may facilitate genetic adaptation by preserving existing genetic variation, releasing cryptic genetic variation and/or facilitating mutations in functional loci. Although we show that examples of non-genetic inheritance are often maladaptive in the short term, accounting for phenotypic variance and non-adaptive plasticity may reveal important evolutionary implications over longer time scales. We also discuss the possibility that maladaptive epigenetic responses may be due to 'epigenetic traps', whereby evolutionarily novel factors (e.g. endocrine disruptors) hack into the existing epigenetic machinery. We stress that more ecologically relevant work on transgenerational epigenetic inheritance is required. Researchers conducting studies on transgenerational environmental effects should report measures of phenotypic variance, so that the possibility of both bet hedging and heritable bet hedging can be assessed. Future empirical and theoretical work is required to assess the relative importance of genetic and epigenetic variation, and their interaction, for evolutionary rescue.

Integrating genomics into evolutionary medicine.

Science.gov (United States)

Rodríguez, Juan Antonio; Marigorta, Urko M; Navarro, Arcadi

2014-12-01

The application of the principles of evolutionary biology into medicine was suggested long ago and is already providing insight into the ultimate causes of disease. However, a full systematic integration of medical genomics and evolutionary medicine is still missing. Here, we briefly review some cases where the combination of the two fields has proven profitable and highlight two of the main issues hindering the development of evolutionary genomic medicine as a mature field, namely the dissociation between fitness and health and the still considerable difficulties in predicting phenotypes from genotypes. We use publicly available data to illustrate both problems and conclude that new approaches are needed for evolutionary genomic medicine to overcome these obstacles. Copyright © 2014 Elsevier Ltd. All rights reserved.

Form of an evolutionary tradeoff affects eco-evolutionary dynamics in a predator-prey system.

Science.gov (United States)

Kasada, Minoru; Yamamichi, Masato; Yoshida, Takehito

2014-11-11

Evolution on a time scale similar to ecological dynamics has been increasingly recognized for the last three decades. Selection mediated by ecological interactions can change heritable phenotypic variation (i.e., evolution), and evolution of traits, in turn, can affect ecological interactions. Hence, ecological and evolutionary dynamics can be tightly linked and important to predict future dynamics, but our understanding of eco-evolutionary dynamics is still in its infancy and there is a significant gap between theoretical predictions and empirical tests. Empirical studies have demonstrated that the presence of genetic variation can dramatically change ecological dynamics, whereas theoretical studies predict that eco-evolutionary dynamics depend on the details of the genetic variation, such as the form of a tradeoff among genotypes, which can be more important than the presence or absence of the genetic variation. Using a predator-prey (rotifer-algal) experimental system in laboratory microcosms, we studied how different forms of a tradeoff between prey defense and growth affect eco-evolutionary dynamics. Our experimental results show for the first time to our knowledge that different forms of the tradeoff produce remarkably divergent eco-evolutionary dynamics, including near fixation, near extinction, and coexistence of algal genotypes, with quantitatively different population dynamics. A mathematical model, parameterized from completely independent experiments, explains the observed dynamics. The results suggest that knowing the details of heritable trait variation and covariation within a population is essential for understanding how evolution and ecology will interact and what form of eco-evolutionary dynamics will result.

Practical advantages of evolutionary computation

Science.gov (United States)

Fogel, David B.

1997-10-01

Evolutionary computation is becoming a common technique for solving difficult, real-world problems in industry, medicine, and defense. This paper reviews some of the practical advantages to using evolutionary algorithms as compared with classic methods of optimization or artificial intelligence. Specific advantages include the flexibility of the procedures, as well as their ability to self-adapt the search for optimum solutions on the fly. As desktop computers increase in speed, the application of evolutionary algorithms will become routine.

Steps towards an evolutionary physics

CERN Document Server

Tiezzi, E

2006-01-01

If thermodynamics is to physics as logic is to philosophy, recent theoretical advancements lend new coherence to the marvel and dynamism of life on Earth. Enzo Tiezzi's "Steps Towards an Evolutionary Physics" is a primer and guide, to those who would to stand on the shoulders of giants to attain this view: Heisenberg, Planck, Bateson, Varela, and Prigogine as well as notable contemporary scientists. The adventure of such a free and enquiring spirit thrives not so much on answers as on new questions. The book offers a new gestalt on the uncertainty principle and concept of probability. A wide range of examples, enigmas, and paradoxes lead one's imagination on an exquisite dance. Among the applications are: songs and shapes of nature, oscillatory reactions, orientors, goal functions and configurations of processes, and "dissipative structures and the city". Ecodynamics is a new science, which proposes a cross-fertilization between Charles Darwin and Ilya Prigogine. As an enigma in thermodynamics, Entropy forms ...

Deterministic network interdiction optimization via an evolutionary approach

International Nuclear Information System (INIS)

Rocco S, Claudio M.; Ramirez-Marquez, Jose Emmanuel

2009-01-01

This paper introduces an evolutionary optimization approach that can be readily applied to solve deterministic network interdiction problems. The network interdiction problem solved considers the minimization of the maximum flow that can be transmitted between a source node and a sink node for a fixed network design when there is a limited amount of resources available to interdict network links. Furthermore, the model assumes that the nominal capacity of each network link and the cost associated with their interdiction can change from link to link. For this problem, the solution approach developed is based on three steps that use: (1) Monte Carlo simulation, to generate potential network interdiction strategies, (2) Ford-Fulkerson algorithm for maximum s-t flow, to analyze strategies' maximum source-sink flow and, (3) an evolutionary optimization technique to define, in probabilistic terms, how likely a link is to appear in the final interdiction strategy. Examples for different sizes of networks and network behavior are used throughout the paper to illustrate the approach. In terms of computational effort, the results illustrate that solutions are obtained from a significantly restricted solution search space. Finally, the authors discuss the need for a reliability perspective to network interdiction, so that solutions developed address more realistic scenarios of such problem

Transgressive Hybrids as Hopeful Monsters.

Science.gov (United States)

Dittrich-Reed, Dylan R; Fitzpatrick, Benjamin M

2013-06-01

The origin of novelty is a critical subject for evolutionary biologists. Early geneticists speculated about the sudden appearance of new species via special macromutations, epitomized by Goldschmidt's infamous "hopeful monster". Although these ideas were easily dismissed by the insights of the Modern Synthesis, a lingering fascination with the possibility of sudden, dramatic change has persisted. Recent work on hybridization and gene exchange suggests an underappreciated mechanism for the sudden appearance of evolutionary novelty that is entirely consistent with the principles of modern population genetics. Genetic recombination in hybrids can produce transgressive phenotypes, "monstrous" phenotypes beyond the range of parental populations. Transgressive phenotypes can be products of epistatic interactions or additive effects of multiple recombined loci. We compare several epistatic and additive models of transgressive segregation in hybrids and find that they are special cases of a general, classic quantitative genetic model. The Dobzhansky-Muller model predicts "hopeless" monsters, sterile and inviable transgressive phenotypes. The Bateson model predicts "hopeful" monsters with fitness greater than either parental population. The complementation model predicts both. Transgressive segregation after hybridization can rapidly produce novel phenotypes by recombining multiple loci simultaneously. Admixed populations will also produce many similar recombinant phenotypes at the same time, increasing the probability that recombinant "hopeful monsters" will establish true-breeding evolutionary lineages. Recombination is not the only (or even most common) process generating evolutionary novelty, but might be the most credible mechanism for sudden appearance of new forms.

Hierarchical Self Organizing Map for Novelty Detection using Mobile Robot with Robust Sensor

International Nuclear Information System (INIS)

Sha'abani, M N A H; Miskon, M F; Sakidin, H

2013-01-01

This paper presents a novelty detection method based on Self Organizing Map neural network using a mobile robot. Based on hierarchical neural network, the network is divided into three networks; position, orientation and sensor measurement network. A simulation was done to demonstrate and validate the proposed method using MobileSim. Three cases of abnormal events; new, missing and shifted objects are employed for performance evaluation. The result of detection was then filtered for false positive detection. The result shows that the inspection produced less than 2% false positive detection at high sensitivity settings

A pronounced evolutionary shift of the pseudoautosomal region boundary in house mice

OpenAIRE

White, Michael A.; Ikeda, Akihiro; Payseur, Bret A.

2012-01-01

The pseudoautosomal region (PAR) is essential for the accurate pairing and segregation of the X and Y chromosomes during meiosis. Despite its functional significance, the PAR shows substantial evolutionary divergence in structure and sequence between mammalian species. An instructive example of PAR evolution is the house mouse Mus musculus domesticus (represented by the C57BL/6J strain), which has the smallest PAR among those that have been mapped. In C57BL/6J, the PAR boundary is located jus...

Calculating evolutionary dynamics in structured populations.

Directory of Open Access Journals (Sweden)

Charles G Nathanson

2009-12-01

Full Text Available Evolution is shaping the world around us. At the core of every evolutionary process is a population of reproducing individuals. The outcome of an evolutionary process depends on population structure. Here we provide a general formula for calculating evolutionary dynamics in a wide class of structured populations. This class includes the recently introduced "games in phenotype space" and "evolutionary set theory." There can be local interactions for determining the relative fitness of individuals, but we require global updating, which means all individuals compete uniformly for reproduction. We study the competition of two strategies in the context of an evolutionary game and determine which strategy is favored in the limit of weak selection. We derive an intuitive formula for the structure coefficient, sigma, and provide a method for efficient numerical calculation.

Asymmetric Evolutionary Games

Science.gov (United States)

McAvoy, Alex; Hauert, Christoph

2015-01-01

Evolutionary game theory is a powerful framework for studying evolution in populations of interacting individuals. A common assumption in evolutionary game theory is that interactions are symmetric, which means that the players are distinguished by only their strategies. In nature, however, the microscopic interactions between players are nearly always asymmetric due to environmental effects, differing baseline characteristics, and other possible sources of heterogeneity. To model these phenomena, we introduce into evolutionary game theory two broad classes of asymmetric interactions: ecological and genotypic. Ecological asymmetry results from variation in the environments of the players, while genotypic asymmetry is a consequence of the players having differing baseline genotypes. We develop a theory of these forms of asymmetry for games in structured populations and use the classical social dilemmas, the Prisoner’s Dilemma and the Snowdrift Game, for illustrations. Interestingly, asymmetric games reveal essential differences between models of genetic evolution based on reproduction and models of cultural evolution based on imitation that are not apparent in symmetric games. PMID:26308326

Towards a Population Dynamics Theory for Evolutionary Computing: Learning from Biological Population Dynamics in Nature

Science.gov (United States)

Ma, Zhanshan (Sam)

In evolutionary computing (EC), population size is one of the critical parameters that a researcher has to deal with. Hence, it was no surprise that the pioneers of EC, such as De Jong (1975) and Holland (1975), had already studied the population sizing from the very beginning of EC. What is perhaps surprising is that more than three decades later, we still largely depend on the experience or ad-hoc trial-and-error approach to set the population size. For example, in a recent monograph, Eiben and Smith (2003) indicated: "In almost all EC applications, the population size is constant and does not change during the evolutionary search." Despite enormous research on this issue in recent years, we still lack a well accepted theory for population sizing. In this paper, I propose to develop a population dynamics theory forEC with the inspiration from the population dynamics theory of biological populations in nature. Essentially, the EC population is considered as a dynamic system over time (generations) and space (search space or fitness landscape), similar to the spatial and temporal dynamics of biological populations in nature. With this conceptual mapping, I propose to 'transplant' the biological population dynamics theory to EC via three steps: (i) experimentally test the feasibility—whether or not emulating natural population dynamics improves the EC performance; (ii) comparatively study the underlying mechanisms—why there are improvements, primarily via statistical modeling analysis; (iii) conduct theoretical analysis with theoretical models such as percolation theory and extended evolutionary game theory that are generally applicable to both EC and natural populations. This article is a summary of a series of studies we have performed to achieve the general goal [27][30]-[32]. In the following, I start with an extremely brief introduction on the theory and models of natural population dynamics (Sections 1 & 2). In Sections 4 to 6, I briefly discuss three

Taxonomic and geographic novelties in the genus Plantago (Plantaginaceae) in Chile, including the description of a new species

DEFF Research Database (Denmark)

Hassemer, Gustavo; Shipunov, Alexey; Rønsted, Nina

2018-01-01

We present taxonomic and geographic novelties in the genus Plantago from Chile. More specifically, we describe P. nebularis, a new species endemic to Cerro Moreno, Antofagasta region, and propose P. zoellneriana, a new name for P. sericea subsp. araucana. We also lectotypify the name P. sericea, ...

Industrial Applications of Evolutionary Algorithms

CERN Document Server

Sanchez, Ernesto; Tonda, Alberto

2012-01-01

This book is intended as a reference both for experienced users of evolutionary algorithms and for researchers that are beginning to approach these fascinating optimization techniques. Experienced users will find interesting details of real-world problems, and advice on solving issues related to fitness computation, modeling and setting appropriate parameters to reach optimal solutions. Beginners will find a thorough introduction to evolutionary computation, and a complete presentation of all evolutionary algorithms exploited to solve different problems. The book could fill the gap between the

Phanerozoic changes in hardpart availability and utilization in benthic communities: evolutionary ecology or evolutionary stratigraphy

Energy Technology Data Exchange (ETDEWEB)

Kidwell, S.M.

1985-01-01

Published experiments on modern communities and quantitative data from Miocene assemblages indicate that the accumulation of dead hardparts can drive specific changes in the composition of benthic communities (taphonomic feedback). Both opportunities and pathways of taphonomic feedback have changed over the Phanerozoic, however, owing to the evolution and environmental expansion of hardpart producers, utilizers, and destroyers. These changes were tracked using semi-quantitative estimates of hardpart availability based on familial diversity of the most abundant taxa, scored according to preservation potential at or near the seafloor. The data suggest a dramatic increase in hardpart availability from the Cambrian into the later Paleozoic, with a decline through the Mesozoic and Cenozoic related to the loss or dramatic reduction in calcitic epifauna, recliners on soft substrata, and large shelled nekton/plankton. The reduction in opportunities for taphonomic feedback among epifauna was accompanied by an increase in levels of infaunal interactions in the Cenozoic, which is characterized by fully three-dimensional shell gravels. In addition to evolutionary change in body sizes of hardpart producers and biotically-driven declines in certain benthic life habits, the change in pathways of taphonomic feedback was also a consequence of the large-scale shift from predominantly carbonate sedimentation in the Paleozoic to predominantly terrigenous sedimentation in the Cenozoic. For example, the waning of epifauna-dominated communities is closely associated with the restriction of level-bottom carbonate environments through the late Mesozoic and Cenozoic. The global evolution of sedimentary environments and their relative representation is important not only in its consequences for sampling but as a driving mechanism of evolutionary ecology of marine benthos.

Core principles of evolutionary medicine: A Delphi study.

Science.gov (United States)

Grunspan, Daniel Z; Nesse, Randolph M; Barnes, M Elizabeth; Brownell, Sara E

2018-01-01

Evolutionary medicine is a rapidly growing field that uses the principles of evolutionary biology to better understand, prevent and treat disease, and that uses studies of disease to advance basic knowledge in evolutionary biology. Over-arching principles of evolutionary medicine have been described in publications, but our study is the first to systematically elicit core principles from a diverse panel of experts in evolutionary medicine. These principles should be useful to advance recent recommendations made by The Association of American Medical Colleges and the Howard Hughes Medical Institute to make evolutionary thinking a core competency for pre-medical education. The Delphi method was used to elicit and validate a list of core principles for evolutionary medicine. The study included four surveys administered in sequence to 56 expert panelists. The initial open-ended survey created a list of possible core principles; the three subsequent surveys winnowed the list and assessed the accuracy and importance of each principle. Fourteen core principles elicited at least 80% of the panelists to agree or strongly agree that they were important core principles for evolutionary medicine. These principles over-lapped with concepts discussed in other articles discussing key concepts in evolutionary medicine. This set of core principles will be helpful for researchers and instructors in evolutionary medicine. We recommend that evolutionary medicine instructors use the list of core principles to construct learning goals. Evolutionary medicine is a young field, so this list of core principles will likely change as the field develops further.

Conceptual Barriers to Progress Within Evolutionary Biology.

Science.gov (United States)

Laland, Kevin N; Odling-Smee, John; Feldman, Marcus W; Kendal, Jeremy

2009-08-01

In spite of its success, Neo-Darwinism is faced with major conceptual barriers to further progress, deriving directly from its metaphysical foundations. Most importantly, neo-Darwinism fails to recognize a fundamental cause of evolutionary change, "niche construction". This failure restricts the generality of evolutionary theory, and introduces inaccuracies. It also hinders the integration of evolutionary biology with neighbouring disciplines, including ecosystem ecology, developmental biology, and the human sciences. Ecology is forced to become a divided discipline, developmental biology is stubbornly difficult to reconcile with evolutionary theory, and the majority of biologists and social scientists are still unhappy with evolutionary accounts of human behaviour. The incorporation of niche construction as both a cause and a product of evolution removes these disciplinary boundaries while greatly generalizing the explanatory power of evolutionary theory.

Evolutionary Statistical Procedures

CERN Document Server

Baragona, Roberto; Poli, Irene

2011-01-01

This proposed text appears to be a good introduction to evolutionary computation for use in applied statistics research. The authors draw from a vast base of knowledge about the current literature in both the design of evolutionary algorithms and statistical techniques. Modern statistical research is on the threshold of solving increasingly complex problems in high dimensions, and the generalization of its methodology to parameters whose estimators do not follow mathematically simple distributions is underway. Many of these challenges involve optimizing functions for which analytic solutions a

Maternal Encouragement to Approach Novelty: A Curvilinear Relation to Change in Anxiety for Inhibited Toddlers.

Science.gov (United States)

Kiel, Elizabeth J; Premo, Julie E; Buss, Kristin A

2016-04-01

Various parenting behaviors (e.g., protection, intrusiveness, sensitivity) have been shown to impact young children's anxiety development, particularly for temperamentally inhibited children. These behaviors have sometimes predicted both increases and decreases in anxiety in inhibited children, suggesting that linear relations may not adequately model their influence. In the current study, we proposed the dimension of encouragement to approach novelty to characterize parenting behavior ranging from very little encouragement (i.e., protective behavior) to very strong encouragement (i.e., intrusiveness), with gentle encouragement residing in the middle. In a sample of 110 toddlers (48 female, 62 male) and their mothers, the linear and curvilinear effects of this parenting dimension were investigated in relation to change in child separation anxiety and shyness from age 2 to age 3. Inhibited temperament was also investigated as a moderator. Encouragement to approach novelty displayed the hypothesized curvilinear relation to change in separation anxiety, but not shyness, at extreme levels of inhibited temperament. Toddlers increased in separation anxiety when mothers' encouragement resided at either extreme end of the continuum, with lower child anxiety occurring when mothers displayed behavior closer to the middle of the continuum. Implications for the study of parenting outcomes for inhibited toddlers are discussed.

Inferring causation from cross-sectional data: Examination of the causal relationship between hyperactivity-impulsivity and novelty seeking

Directory of Open Access Journals (Sweden)

Alexis Caroline Wood

2011-03-01

Full Text Available Previous research suggests an association between hyperactivity-impulsivity – one of the two behavioural dimensions that form attention deficit hyperactivity disorder – and the temperament characteristic of novelty seeking. We aimed to examine etiological links underlying the co-occurrence between these behaviours using a general population sample of 668 twin pairs, ages 7-10, for whom we obtained parent ratings in middle childhood; and pilot longitudinal data on 76 children. Structural equation modelling confirmed a shared genetic etiology (genetic correlation, rD=.81; 95% confidence intervals [CI]= .34-1.00 and showed that much (64% of the covariation can be accounted for by shared genetic effects. In addition, causal paths were modelled between the two behaviours; 12% of the variance in novelty seeking at age 7 was accounted for by hyperactive-impulsive behaviors at the same age. The causal effects model fits with the current characterization of hyperactive-impulsive behaviors reflecting a heightened need for stimulation. This has important implications for the management of hyperactive-impulsive behaviors in clinical settings.

Part E: Evolutionary Computation

DEFF Research Database (Denmark)

2015-01-01

of Computational Intelligence. First, comprehensive surveys of genetic algorithms, genetic programming, evolution strategies, parallel evolutionary algorithms are presented, which are readable and constructive so that a large audience might find them useful and – to some extent – ready to use. Some more general...... kinds of evolutionary algorithms, have been prudently analyzed. This analysis was followed by a thorough analysis of various issues involved in stochastic local search algorithms. An interesting survey of various technological and industrial applications in mechanical engineering and design has been...... topics like the estimation of distribution algorithms, indicator-based selection, etc., are also discussed. An important problem, from a theoretical and practical point of view, of learning classifier systems is presented in depth. Multiobjective evolutionary algorithms, which constitute one of the most...

Contemporary issues in evolutionary biology

Indian Academy of Sciences (India)

These discussions included, among others, the possible consequences of nonDNA-based inheritance—epigenetics and cultural evolution, niche construction, and developmental mechanisms on our understanding of the evolutionary process, speciation, complexity in biology, and constructing a formal evolutionary theory.

Evolutionary dynamics of protein domain architecture in plants

Directory of Open Access Journals (Sweden)

Zhang Xue-Cheng

2012-01-01

Full Text Available Abstract Background Protein domains are the structural, functional and evolutionary units of the protein. Protein domain architectures are the linear arrangements of domain(s in individual proteins. Although the evolutionary history of protein domain architecture has been extensively studied in microorganisms, the evolutionary dynamics of domain architecture in the plant kingdom remains largely undefined. To address this question, we analyzed the lineage-based protein domain architecture content in 14 completed green plant genomes. Results Our analyses show that all 14 plant genomes maintain similar distributions of species-specific, single-domain, and multi-domain architectures. Approximately 65% of plant domain architectures are universally present in all plant lineages, while the remaining architectures are lineage-specific. Clear examples are seen of both the loss and gain of specific protein architectures in higher plants. There has been a dynamic, lineage-wise expansion of domain architectures during plant evolution. The data suggest that this expansion can be largely explained by changes in nuclear ploidy resulting from rounds of whole genome duplications. Indeed, there has been a decrease in the number of unique domain architectures when the genomes were normalized into a presumed ancestral genome that has not undergone whole genome duplications. Conclusions Our data show the conservation of universal domain architectures in all available plant genomes, indicating the presence of an evolutionarily conserved, core set of protein components. However, the occurrence of lineage-specific domain architectures indicates that domain architecture diversity has been maintained beyond these core components in plant genomes. Although several features of genome-wide domain architecture content are conserved in plants, the data clearly demonstrate lineage-wise, progressive changes and expansions of individual protein domain architectures, reinforcing

Large-Scale Phylogenomic Analysis Reveals the Complex Evolutionary History of Rabies Virus in Multiple Carnivore Hosts.

Directory of Open Access Journals (Sweden)

Cécile Troupin

2016-12-01

Full Text Available The natural evolution of rabies virus (RABV provides a potent example of multiple host shifts and an important opportunity to determine the mechanisms that underpin viral emergence. Using 321 genome sequences spanning an unprecedented diversity of RABV, we compared evolutionary rates and selection pressures in viruses sampled from multiple primary host shifts that occurred on various continents. Two major phylogenetic groups, bat-related RABV and dog-related RABV, experiencing markedly different evolutionary dynamics were identified. While no correlation between time and genetic divergence was found in bat-related RABV, the evolution of dog-related RABV followed a generally clock-like structure, although with a relatively low evolutionary rate. Subsequent molecular clock dating indicated that dog-related RABV likely underwent a rapid global spread following the intensification of intercontinental trade starting in the 15th century. Strikingly, although dog RABV has jumped to various wildlife species from the order Carnivora, we found no clear evidence that these host-jumping events involved adaptive evolution, with RABV instead characterized by strong purifying selection, suggesting that ecological processes also play an important role in shaping patterns of emergence. However, specific amino acid changes were associated with the parallel emergence of RABV in ferret-badgers in Asia, and some host shifts were associated with increases in evolutionary rate, particularly in the ferret-badger and mongoose, implying that changes in host species can have important impacts on evolutionary dynamics.

Evolutionary and Comparative Genomics to Drive Rational Drug Design, with Particular Focus on Neuropeptide Seven-Transmembrane Receptors.

Science.gov (United States)

Furlong, Michael; Seong, Jae Young

2017-01-01

Seven transmembrane receptors (7TMRs), also known as G protein-coupled receptors, are popular targets of drug development, particularly 7TMR systems that are activated by peptide ligands. Although many pharmaceutical drugs have been discovered via conventional bulk analysis techniques the increasing availability of structural and evolutionary data are facilitating change to rational, targeted drug design. This article discusses the appeal of neuropeptide-7TMR systems as drug targets and provides an overview of concepts in the evolution of vertebrate genomes and gene families. Subsequently, methods that use evolutionary concepts and comparative analysis techniques to aid in gene discovery, gene function identification, and novel drug design are provided along with case study examples.

Novelty-Induced Arousal Enhances Memory for Cued Classical Fear Conditioning: Interactions between Peripheral Adrenergic and Brainstem Glutamatergic Systems

Science.gov (United States)

King, Stanley O., II; Williams, Cedric L.

2009-01-01

Exposure to novel contexts produce heightened states of arousal and biochemical changes in the brain to consolidate memory. However, processes permitting simple exposure to unfamiliar contexts to elevate sympathetic output and to improve memory are poorly understood. This shortcoming was addressed by examining how novelty-induced changes in…

Novelty-induced activity-regulated cytoskeletal-associated protein (Arc) expression in frontal cortex requires serotonin 2A receptor activation

DEFF Research Database (Denmark)

Santini, Martin; Klein, A B; El-Sayed, M

2011-01-01

environment. As an output of FC activation we measured expression of activity-regulated cytoskeletal-associated protein (Arc). Novelty-exposure (open-field arena) robustly up-regulated FC Arc mRNA expression (∼160%) in mice compared to home-cage controls. This response was inhibited with the 5-HT(2A...

Novelty-induced activity-regulated cytoskeletal-associated protein (Arc) expression in frontal cortex requires serotonin 2A receptor activation

DEFF Research Database (Denmark)

Santini, Martin; Klein, A B; El-Sayed, M

2011-01-01

environment. As an output of FC activation we measured expression of activity-regulated cytoskeletal-associated protein (Arc). Novelty-exposure (open-field arena) robustly up-regulated FC Arc mRNA expression (~160%) in mice compared to home-cage controls. This response was inhibited with the 5-HT(2A...

Applications of evolutionary economic geography

NARCIS (Netherlands)

Boschma, R.A.; Frenken, K.; Puranam, Krishna Kishore; Ravi Kumar Jain B., xx

2008-01-01

This paper is written as the first chapter of an edited volume on evolutionary economics and economic geography (Frenken, K., editor, Applied Evolutionary Economics and Economic Geography, Cheltenham: Edward Elgar, expected publication date February 2007). The paper reviews empirical applications of

Selection of energy source and evolutionary stable strategies for power plants under financial intervention of government

Science.gov (United States)

Hafezalkotob, Ashkan; Mahmoudi, Reza

2017-09-01

Currently, many socially responsible governments adopt economic incentives and deterrents to manage environmental impacts of electricity suppliers. Considering the Stackelberg leadership of the government, the government's role in the competition of power plants in an electricity market is investigated. A one-population evolutionary game model of power plants is developed to study how their production strategy depends on tariffs levied by the government. We establish that a unique evolutionary stable strategy (ESS) for the population exists. Numerical examples demonstrate that revenue maximization and environment protection policies of the government significantly affect the production ESS of competitive power plants. The results reveal that the government can introduce a green energy source as an ESS of the competitive power plants by imposing appropriate tariffs.

A Multi Agent System for Flow-Based Intrusion Detection Using Reputation and Evolutionary Computation

Science.gov (United States)

2011-03-01

pertinent example of the application of Evolutionary Algorithms to pattern recognition comes from Radtke et al. [130]. The authors apply Multi- Objective...J., T. Zseby, and B. Claise. S. Zander,” Requirements for IP Flow Information Export (IPFIX). Technical report, RFC 3917, October 2004. [130] Radtke ...hal.inria.fr/inria-00104200/en/. [131] Radtke , P.V.W., T. Wong, and R. Sabourin. “A multi-objective memetic al- gorithm for intelligent feature extraction

Environmental novelty and illumination modify ethanol-induced open-field behavioral effects in mice.

Science.gov (United States)

Fukushiro, Daniela F; Benetti, Liliane F; Josino, Fabiana S; Oliveira, Gabriela P; Fernandes, Maiara deM; Saito, Luis P; Uehara, Regina A; Wuo-Silva, Raphael; Oliveira, Camila S; Frussa-Filho, Roberto

2010-03-01

Both spontaneous and drug-induced animal behaviors can be modified by exposure to novel stimuli or different levels of environmental illumination. However, research into how these factors specifically impact ethanol (ETH)-induced behavioral effects is currently lacking. We aimed to investigate the effects of these two factors, considered separately or in conjunction, on ETH-induced acute hyperlocomotor effect and its sensitization in adult male Swiss mice. Mice were placed in a novel or familiar open-field under normal light (200 lx) or low light (9 lx) immediately after receiving an ip injection of either 1.8 g/kg ETH or saline (SAL). After 7 days, all animals received an ip challenge injection of 1.8 g/kg ETH, and were placed in the open-field under the same light conditions described above. Novelty increased central locomotion and decreased grooming, while low light increased grooming. Acute ETH administration increased both total and peripheral locomotion and these effects were potentiated by low light. Both low light and novelty were able to facilitate ETH-induced locomotor sensitization, which was detected by the central locomotion parameter. However, there was no synergism between the effects of these two modulating factors on ETH-induced behavioral sensitization. We conclude that both the acute behavioral effects of ETH and behavioral sensitization induced by previous administration of this drug can be critically modified by environmental factors. In addition, our study stresses the importance of using different behavioral parameters to evaluate the interaction between environmental factors and ETH effects. (c) 2009 Elsevier Inc. All rights reserved.

Fast stochastic algorithm for simulating evolutionary population dynamics

Science.gov (United States)

Tsimring, Lev; Hasty, Jeff; Mather, William

2012-02-01

Evolution and co-evolution of ecological communities are stochastic processes often characterized by vastly different rates of reproduction and mutation and a coexistence of very large and very small sub-populations of co-evolving species. This creates serious difficulties for accurate statistical modeling of evolutionary dynamics. In this talk, we introduce a new exact algorithm for fast fully stochastic simulations of birth/death/mutation processes. It produces a significant speedup compared to the direct stochastic simulation algorithm in a typical case when the total population size is large and the mutation rates are much smaller than birth/death rates. We illustrate the performance of the algorithm on several representative examples: evolution on a smooth fitness landscape, NK model, and stochastic predator-prey system.

Phylogenetic uncertainty can bias the number of evolutionary transitions estimated from ancestral state reconstruction methods.

Science.gov (United States)

Duchêne, Sebastian; Lanfear, Robert

2015-09-01

Ancestral state reconstruction (ASR) is a popular method for exploring the evolutionary history of traits that leave little or no trace in the fossil record. For example, it has been used to test hypotheses about the number of evolutionary origins of key life-history traits such as oviparity, or key morphological structures such as wings. Many studies that use ASR have suggested that the number of evolutionary origins of such traits is higher than was previously thought. The scope of such inferences is increasing rapidly, facilitated by the construction of very large phylogenies and life-history databases. In this paper, we use simulations to show that the number of evolutionary origins of a trait tends to be overestimated when the phylogeny is not perfect. In some cases, the estimated number of transitions can be several fold higher than the true value. Furthermore, we show that the bias is not always corrected by standard approaches to account for phylogenetic uncertainty, such as repeating the analysis on a large collection of possible trees. These findings have important implications for studies that seek to estimate the number of origins of a trait, particularly those that use large phylogenies that are associated with considerable uncertainty. We discuss the implications of this bias, and methods to ameliorate it. © 2015 Wiley Periodicals, Inc.

Evolutionary disarmament in interspecific competition.

Science.gov (United States)

Kisdi, E; Geritz, S A

2001-12-22

Competitive asymmetry, which is the advantage of having a larger body or stronger weaponry than a contestant, drives spectacular evolutionary arms races in intraspecific competition. Similar asymmetries are well documented in interspecific competition, yet they seldom lead to exaggerated traits. Here we demonstrate that two species with substantially different size may undergo parallel coevolution towards a smaller size under the same ecological conditions where a single species would exhibit an evolutionary arms race. We show that disarmament occurs for a wide range of parameters in an ecologically explicit model of competition for a single shared resource; disarmament also occurs in a simple Lotka-Volterra competition model. A key property of both models is the interplay between evolutionary dynamics and population density. The mechanism does not rely on very specific features of the model. Thus, evolutionary disarmament may be widespread and may help to explain the lack of interspecific arms races.

Incorporating evolutionary principles into environmental management and policy

DEFF Research Database (Denmark)

Lankau, Richard; Jørgensen, Peter Søgaard; Harris, David J.

2011-01-01

As policymakers and managers work to mitigate the effects of rapid anthropogenic environmental changes, they need to consider organisms’ responses. In light of recent evidence that evolution can be quite rapid, this now includes evolutionary responses. Evolutionary principles have a long history...... in conservation biology, and the necessary next step for the field is to consider ways in which conservation policy makers and managers can proactively manipulate evolutionary processes to achieve their goals. In this review, we aim to illustrate the potential conservation benefits of an increased understanding...... of evolutionary history and prescriptive manipulation of three basic evolutionary factors: selection, variation, and gene flow. For each, we review and propose ways that policy makers and managers can use evolutionary thinking to preserve threatened species, combat pest species, or reduce undesirable evolutionary...

Ancient Origin of the Tryptophan Operon and the Dynamics of Evolutionary Change†

Science.gov (United States)

Xie, Gary; Keyhani, Nemat O.; Bonner; Jensen, Roy A.

2003-01-01

The seven conserved enzymatic domains required for tryptophan (Trp) biosynthesis are encoded in seven genetic regions that are organized differently (whole-pathway operons, multiple partial-pathway operons, and dispersed genes) in prokaryotes. A comparative bioinformatics evaluation of the conservation and organization of the genes of Trp biosynthesis in prokaryotic operons should serve as an excellent model for assessing the feasibility of predicting the evolutionary histories of genes and operons associated with other biochemical pathways. These comparisons should provide a better understanding of possible explanations for differences in operon organization in different organisms at a genomics level. These analyses may also permit identification of some of the prevailing forces that dictated specific gene rearrangements during the course of evolution. Operons concerned with Trp biosynthesis in prokaryotes have been in a dynamic state of flux. Analysis of closely related organisms among the Bacteria at various phylogenetic nodes reveals many examples of operon scission, gene dispersal, gene fusion, gene scrambling, and gene loss from which the direction of evolutionary events can be deduced. Two milestone evolutionary events have been mapped to the 16S rRNA tree of Bacteria, one splitting the operon in two, and the other rejoining it by gene fusion. The Archaea, though less resolved due to a lesser genome representation, appear to exhibit more gene scrambling than the Bacteria. The trp operon appears to have been an ancient innovation; it was already present in the common ancestor of Bacteria and Archaea. Although the operon has been subjected, even in recent times, to dynamic changes in gene rearrangement, the ancestral gene order can be deduced with confidence. The evolutionary history of the genes of the pathway is discernible in rough outline as a vertical line of descent, with events of lateral gene transfer or paralogy enriching the analysis as interesting

Ancient origin of the tryptophan operon and the dynamics of evolutionary change.

Science.gov (United States)

Xie, Gary; Keyhani, Nemat O; Bonner, Carol A; Jensen, Roy A

2003-09-01

The seven conserved enzymatic domains required for tryptophan (Trp) biosynthesis are encoded in seven genetic regions that are organized differently (whole-pathway operons, multiple partial-pathway operons, and dispersed genes) in prokaryotes. A comparative bioinformatics evaluation of the conservation and organization of the genes of Trp biosynthesis in prokaryotic operons should serve as an excellent model for assessing the feasibility of predicting the evolutionary histories of genes and operons associated with other biochemical pathways. These comparisons should provide a better understanding of possible explanations for differences in operon organization in different organisms at a genomics level. These analyses may also permit identification of some of the prevailing forces that dictated specific gene rearrangements during the course of evolution. Operons concerned with Trp biosynthesis in prokaryotes have been in a dynamic state of flux. Analysis of closely related organisms among the Bacteria at various phylogenetic nodes reveals many examples of operon scission, gene dispersal, gene fusion, gene scrambling, and gene loss from which the direction of evolutionary events can be deduced. Two milestone evolutionary events have been mapped to the 16S rRNA tree of Bacteria, one splitting the operon in two, and the other rejoining it by gene fusion. The Archaea, though less resolved due to a lesser genome representation, appear to exhibit more gene scrambling than the Bacteria. The trp operon appears to have been an ancient innovation; it was already present in the common ancestor of Bacteria and Archaea. Although the operon has been subjected, even in recent times, to dynamic changes in gene rearrangement, the ancestral gene order can be deduced with confidence. The evolutionary history of the genes of the pathway is discernible in rough outline as a vertical line of descent, with events of lateral gene transfer or paralogy enriching the analysis as interesting

Evolutionary economics and industry location

NARCIS (Netherlands)

Boschma, R.A.; Frenken, K.

2003-01-01

This paper aims to provide the outlines of an evolutionary economic geography of industry location. We discuss two evolutionary explanations of industry location, that is, one that concentrates on spin-offs, and one that focuses attention on knowledge and agglomeration economies. We claim that both

Probing the lifetimes of auditory novelty detection processes.

Science.gov (United States)

Pegado, Felipe; Bekinschtein, Tristan; Chausson, Nicolas; Dehaene, Stanislas; Cohen, Laurent; Naccache, Lionel

2010-08-01

Auditory novelty detection can be fractionated into multiple cognitive processes associated with their respective neurophysiological signatures. In the present study we used high-density scalp event-related potentials (ERPs) during an active version of the auditory oddball paradigm to explore the lifetimes of these processes by varying the stimulus onset asynchrony (SOA). We observed that early MMN (90-160 ms) decreased when the SOA increased, confirming the evanescence of this echoic memory system. Subsequent neural events including late MMN (160-220 ms) and P3a/P3b components of the P3 complex (240-500 ms) did not decay with SOA, but showed a systematic delay effect supporting a two-stage model of accumulation of evidence. On the basis of these observations, we propose a distinction within the MMN complex of two distinct events: (1) an early, pre-attentive and fast-decaying MMN associated with generators located within superior temporal gyri (STG) and frontal cortex, and (2) a late MMN more resistant to SOA, corresponding to the activation of a distributed cortical network including fronto-parietal regions. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

Evolutionary institutionalism.

Science.gov (United States)

Fürstenberg, Dr Kai

Institutions are hard to define and hard to study. Long prominent in political science have been two theories: Rational Choice Institutionalism (RCI) and Historical Institutionalism (HI). Arising from the life sciences is now a third: Evolutionary Institutionalism (EI). Comparative strengths and weaknesses of these three theories warrant review, and the value-to-be-added by expanding the third beyond Darwinian evolutionary theory deserves consideration. Should evolutionary institutionalism expand to accommodate new understanding in ecology, such as might apply to the emergence of stability, and in genetics, such as might apply to political behavior? Core arguments are reviewed for each theory with more detailed exposition of the third, EI. Particular attention is paid to EI's gene-institution analogy; to variation, selection, and retention of institutional traits; to endogeneity and exogeneity; to agency and structure; and to ecosystem effects, institutional stability, and empirical limitations in behavioral genetics. RCI, HI, and EI are distinct but complementary. Institutional change, while amenable to rational-choice analysis and, retrospectively, to criticaljuncture and path-dependency analysis, is also, and importantly, ecological. Stability, like change, is an emergent property of institutions, which tend to stabilize after change in a manner analogous to allopatric speciation. EI is more than metaphorically biological in that institutional behaviors are driven by human behaviors whose evolution long preceded the appearance of institutions themselves.

A pronounced evolutionary shift of the pseudoautosomal region boundary in house mice.

Science.gov (United States)

White, Michael A; Ikeda, Akihiro; Payseur, Bret A

2012-08-01

The pseudoautosomal region (PAR) is essential for the accurate pairing and segregation of the X and Y chromosomes during meiosis. Despite its functional significance, the PAR shows substantial evolutionary divergence in structure and sequence between mammalian species. An instructive example of PAR evolution is the house mouse Mus musculus domesticus (represented by the C57BL/6J strain), which has the smallest PAR among those that have been mapped. In C57BL/6J, the PAR boundary is located just ~700 kb from the distal end of the X chromosome, whereas the boundary is found at a more proximal position in Mus spretus, a species that diverged from house mice 2-4 million years ago. In this study we used a combination of genetic and physical mapping to document a pronounced shift in the PAR boundary in a second house mouse subspecies, Mus musculus castaneus (represented by the CAST/EiJ strain), ~430 kb proximal of the M. m. domesticus boundary. We demonstrate molecular evolutionary consequences of this shift, including a marked lineage-specific increase in sequence divergence within Mid1, a gene that resides entirely within the M. m. castaneus PAR but straddles the boundary in other subspecies. Our results extend observations of structural divergence in the PAR to closely related subspecies, pointing to major evolutionary changes in this functionally important genomic region over a short time period.

Evolutionary Turnover of Kinetochore Proteins: A Ship of Theseus?

Science.gov (United States)

Drinnenberg, Ines A; Henikoff, Steven; Malik, Harmit S

2016-07-01

The kinetochore is a multiprotein complex that mediates the attachment of a eukaryotic chromosome to the mitotic spindle. The protein composition of kinetochores is similar across species as divergent as yeast and human. However, recent findings have revealed an unexpected degree of compositional diversity in kinetochores. For example, kinetochore proteins that are essential in some species have been lost in others, whereas new kinetochore proteins have emerged in other lineages. Even in lineages with similar kinetochore composition, individual kinetochore proteins have functionally diverged to acquire either essential or redundant roles. Thus, despite functional conservation, the repertoire of kinetochore proteins has undergone recurrent evolutionary turnover. Copyright © 2016 Elsevier Ltd. All rights reserved.

Maternal Accuracy and Behavior in Anticipating Children's Responses to Novelty: Relations to Fearful Temperament and Implications for Anxiety Development

Science.gov (United States)

Kiel, Elizabeth J.; Buss, Kristin A.

2010-01-01

Previous research has suggested that mothers' behaviors may serve as a mechanism in the development from toddler fearful temperament to childhood anxiety. The current study examined the maternal characteristic of accuracy in predicting toddlers' distress reactions to novelty in relation to temperament, parenting, and anxiety development.…

Gender Inequality in Interaction--An Evolutionary Account

Science.gov (United States)

Hopcroft, Rosemary L.

2009-01-01

In this article I argue that evolutionary theorizing can help sociologists and feminists better understand gender inequality. Evolutionary theory explains why control of the sexuality of young women is a priority across most human societies both past and present. Evolutionary psychology has extended our understanding of male violence against…

Making evolutionary biology a basic science for medicine

Science.gov (United States)

Nesse, Randolph M.; Bergstrom, Carl T.; Ellison, Peter T.; Flier, Jeffrey S.; Gluckman, Peter; Govindaraju, Diddahally R.; Niethammer, Dietrich; Omenn, Gilbert S.; Perlman, Robert L.; Schwartz, Mark D.; Thomas, Mark G.; Stearns, Stephen C.; Valle, David

2010-01-01

New applications of evolutionary biology in medicine are being discovered at an accelerating rate, but few physicians have sufficient educational background to use them fully. This article summarizes suggestions from several groups that have considered how evolutionary biology can be useful in medicine, what physicians should learn about it, and when and how they should learn it. Our general conclusion is that evolutionary biology is a crucial basic science for medicine. In addition to looking at established evolutionary methods and topics, such as population genetics and pathogen evolution, we highlight questions about why natural selection leaves bodies vulnerable to disease. Knowledge about evolution provides physicians with an integrative framework that links otherwise disparate bits of knowledge. It replaces the prevalent view of bodies as machines with a biological view of bodies shaped by evolutionary processes. Like other basic sciences, evolutionary biology needs to be taught both before and during medical school. Most introductory biology courses are insufficient to establish competency in evolutionary biology. Premedical students need evolution courses, possibly ones that emphasize medically relevant aspects. In medical school, evolutionary biology should be taught as one of the basic medical sciences. This will require a course that reviews basic principles and specific medical applications, followed by an integrated presentation of evolutionary aspects that apply to each disease and organ system. Evolutionary biology is not just another topic vying for inclusion in the curriculum; it is an essential foundation for a biological understanding of health and disease. PMID:19918069

A sense of life: computational and experimental investigations with models of biochemical and evolutionary processes.

Science.gov (United States)

Mishra, Bud; Daruwala, Raoul-Sam; Zhou, Yi; Ugel, Nadia; Policriti, Alberto; Antoniotti, Marco; Paxia, Salvatore; Rejali, Marc; Rudra, Archisman; Cherepinsky, Vera; Silver, Naomi; Casey, William; Piazza, Carla; Simeoni, Marta; Barbano, Paolo; Spivak, Marina; Feng, Jiawu; Gill, Ofer; Venkatesh, Mysore; Cheng, Fang; Sun, Bing; Ioniata, Iuliana; Anantharaman, Thomas; Hubbard, E Jane Albert; Pnueli, Amir; Harel, David; Chandru, Vijay; Hariharan, Ramesh; Wigler, Michael; Park, Frank; Lin, Shih-Chieh; Lazebnik, Yuri; Winkler, Franz; Cantor, Charles R; Carbone, Alessandra; Gromov, Mikhael

2003-01-01

We collaborate in a research program aimed at creating a rigorous framework, experimental infrastructure, and computational environment for understanding, experimenting with, manipulating, and modifying a diverse set of fundamental biological processes at multiple scales and spatio-temporal modes. The novelty of our research is based on an approach that (i) requires coevolution of experimental science and theoretical techniques and (ii) exploits a certain universality in biology guided by a parsimonious model of evolutionary mechanisms operating at the genomic level and manifesting at the proteomic, transcriptomic, phylogenic, and other higher levels. Our current program in "systems biology" endeavors to marry large-scale biological experiments with the tools to ponder and reason about large, complex, and subtle natural systems. To achieve this ambitious goal, ideas and concepts are combined from many different fields: biological experimentation, applied mathematical modeling, computational reasoning schemes, and large-scale numerical and symbolic simulations. From a biological viewpoint, the basic issues are many: (i) understanding common and shared structural motifs among biological processes; (ii) modeling biological noise due to interactions among a small number of key molecules or loss of synchrony; (iii) explaining the robustness of these systems in spite of such noise; and (iv) cataloging multistatic behavior and adaptation exhibited by many biological processes.

The hormetic zone: an ecological and evolutionary perspective based upon habitat characteristics and fitness selection.

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Parsons, P A

2001-12-01

Fitness varies nonlinearly with environmental variables such as temperature, water availability, and nutrition, with maximum fitness at intermediate levels between more stressful extremes. For environmental agents that are highly toxic at exposures that substantially exceed background levels, fitness is maximized at concentrations near zero--a phenomenon often referred to as hormesis. Two main components are suggested: (1) background hormesis, which derives from the direct adaptation of organisms to their habitats; and (2) stress-derived hormonesis, which derives from metabolic reserves that are maintained as an adaptation to environmental stresses through evolutionary time. These reserves provide protection from lesser correlated stresses. This article discusses illustrative examples, including ethanol and ionizing radiation, aimed at placing hormesis into an ecological and evolutionary context. A unifying approach comes from fitness-stress continua that underlie responses to abiotic variables, whereby selection for maximum metabolic efficiency and hence fitness in adaptation to habitats in nature underlies hormetic zones. Within this reductionist model, more specific metabolic mechanisms to explain hormesis are beginning to emerge, depending upon the agent and the taxon in question. Some limited research possibilities based upon this evolutionary perspective are indicated.

Contemporary issues in evolutionary biology

Indian Academy of Sciences (India)

We are delighted to bring to the readers, a set of peer-reviewed papers on evolutionary biology, published as a special issue of the Journal of Genetics. These papers emanated from ruminations upon and discussions at the Foundations of. Evolutionary Theory: the Ongoing Synthesis meeting at Coorg, India, in February ...

Evolutionary global optimization, manifolds and applications

CERN Document Server

Aguiar e Oliveira Junior, Hime

2016-01-01

This book presents powerful techniques for solving global optimization problems on manifolds by means of evolutionary algorithms, and shows in practice how these techniques can be applied to solve real-world problems. It describes recent findings and well-known key facts in general and differential topology, revisiting them all in the context of application to current optimization problems. Special emphasis is put on game theory problems. Here, these problems are reformulated as constrained global optimization tasks and solved with the help of Fuzzy ASA. In addition, more abstract examples, including minimizations of well-known functions, are also included. Although the Fuzzy ASA approach has been chosen as the main optimizing paradigm, the book suggests that other metaheuristic methods could be used as well. Some of them are introduced, together with their advantages and disadvantages. Readers should possess some knowledge of linear algebra, and of basic concepts of numerical analysis and probability theory....

Archaeogenetics in evolutionary medicine.

Science.gov (United States)

Bouwman, Abigail; Rühli, Frank

2016-09-01

Archaeogenetics is the study of exploration of ancient DNA (aDNA) of more than 70 years old. It is an important part of the wider studies of many different areas of our past, including animal, plant and pathogen evolution and domestication events. Hereby, we address specifically the impact of research in archaeogenetics in the broader field of evolutionary medicine. Studies on ancient hominid genomes help to understand even modern health patterns. Human genetic microevolution, e.g. related to abilities of post-weaning milk consumption, and specifically genetic adaptation in disease susceptibility, e.g. towards malaria and other infectious diseases, are of the upmost importance in contributions of archeogenetics on the evolutionary understanding of human health and disease. With the increase in both the understanding of modern medical genetics and the ability to deep sequence ancient genetic information, the field of archaeogenetic evolutionary medicine is blossoming.

MEGA5: Molecular Evolutionary Genetics Analysis Using Maximum Likelihood, Evolutionary Distance, and Maximum Parsimony Methods

Science.gov (United States)

Tamura, Koichiro; Peterson, Daniel; Peterson, Nicholas; Stecher, Glen; Nei, Masatoshi; Kumar, Sudhir

2011-01-01

Comparative analysis of molecular sequence data is essential for reconstructing the evolutionary histories of species and inferring the nature and extent of selective forces shaping the evolution of genes and species. Here, we announce the release of Molecular Evolutionary Genetics Analysis version 5 (MEGA5), which is a user-friendly software for mining online databases, building sequence alignments and phylogenetic trees, and using methods of evolutionary bioinformatics in basic biology, biomedicine, and evolution. The newest addition in MEGA5 is a collection of maximum likelihood (ML) analyses for inferring evolutionary trees, selecting best-fit substitution models (nucleotide or amino acid), inferring ancestral states and sequences (along with probabilities), and estimating evolutionary rates site-by-site. In computer simulation analyses, ML tree inference algorithms in MEGA5 compared favorably with other software packages in terms of computational efficiency and the accuracy of the estimates of phylogenetic trees, substitution parameters, and rate variation among sites. The MEGA user interface has now been enhanced to be activity driven to make it easier for the use of both beginners and experienced scientists. This version of MEGA is intended for the Windows platform, and it has been configured for effective use on Mac OS X and Linux desktops. It is available free of charge from http://www.megasoftware.net. PMID:21546353

Viewing the Personality Traits Through a Cerebellar Lens: a Focus on the Constructs of Novelty Seeking, Harm Avoidance, and Alexithymia.

Science.gov (United States)

Petrosini, Laura; Cutuli, Debora; Picerni, Eleonora; Laricchiuta, Daniela

2017-02-01

The variance in the range of personality trait expression appears to be linked to structural variance in specific brain regions. In evidencing associations between personality factors and neurobiological measures, it seems evident that the cerebellum has not been up to now thought as having a key role in personality. This paper will review the most recent structural and functional neuroimaging literature that engages the cerebellum in personality traits, as novelty seeking and harm avoidance, and it will discuss the findings in the context of contemporary theories of affective and cognitive cerebellar function. By using region of interest (ROI)- and voxel-based approaches, we recently evidenced that the cerebellar volumes correlate positively with novelty seeking scores and negatively with harm avoidance scores. Subjects who search for new situations as a novelty seeker does (and a harm avoiding does not do) show a different engagement of their cerebellar circuitries in order to rapidly adapt to changing environments. The emerging model of cerebellar functionality may explain how the cerebellar abilities in planning, controlling, and putting into action the behavior are associated to normal or abnormal personality constructs. In this framework, it is worth reporting that increased cerebellar volumes are even associated with high scores in alexithymia, construct of personality characterized by impairment in cognitive, emotional, and affective processing. On such a basis, it seems necessary to go over the traditional cortico-centric view of personality constructs and to address the function of the cerebellar system in sustaining aspects of motivational network that characterizes the different temperamental traits.

Evolutionary relevance facilitates visual information processing.

Science.gov (United States)

Jackson, Russell E; Calvillo, Dusti P

2013-11-03

Visual search of the environment is a fundamental human behavior that perceptual load affects powerfully. Previously investigated means for overcoming the inhibitions of high perceptual load, however, generalize poorly to real-world human behavior. We hypothesized that humans would process evolutionarily relevant stimuli more efficiently than evolutionarily novel stimuli, and evolutionary relevance would mitigate the repercussions of high perceptual load during visual search. Animacy is a significant component to evolutionary relevance of visual stimuli because perceiving animate entities is time-sensitive in ways that pose significant evolutionary consequences. Participants completing a visual search task located evolutionarily relevant and animate objects fastest and with the least impact of high perceptual load. Evolutionarily novel and inanimate objects were located slowest and with the highest impact of perceptual load. Evolutionary relevance may importantly affect everyday visual information processing.

Mean-Potential Law in Evolutionary Games

Science.gov (United States)

Nałecz-Jawecki, Paweł; Miekisz, Jacek

2018-01-01

The Letter presents a novel way to connect random walks, stochastic differential equations, and evolutionary game theory. We introduce a new concept of a potential function for discrete-space stochastic systems. It is based on a correspondence between one-dimensional stochastic differential equations and random walks, which may be exact not only in the continuous limit but also in finite-state spaces. Our method is useful for computation of fixation probabilities in discrete stochastic dynamical systems with two absorbing states. We apply it to evolutionary games, formulating two simple and intuitive criteria for evolutionary stability of pure Nash equilibria in finite populations. In particular, we show that the 1 /3 law of evolutionary games, introduced by Nowak et al. [Nature, 2004], follows from a more general mean-potential law.

Is evolutionary psychology a metatheory for psychology? A discussion of four major issues in psychology from an evolutionary developmental perspective

NARCIS (Netherlands)

Ploeger, A.; van der Maas, H.L.J.; Raijmakers, M.E.J.

2008-01-01

Evolutionary psychology has been proposed as a metatheoretical framework for psychology. We argue that evolutionary psychology should be expanded if it is to offer new insights regarding the major issues in psychology. Evolutionary developmental biology can provide valuable new insights into issues

Comparison of evolutionary computation algorithms for solving bi ...

Indian Academy of Sciences (India)

failure probability. Multiobjective Evolutionary Computation algorithms (MOEAs) are well-suited for Multiobjective task scheduling on heterogeneous environment. The two Multi-Objective Evolutionary Algorithms such as Multiobjective Genetic. Algorithm (MOGA) and Multiobjective Evolutionary Programming (MOEP) with.

Species co-evolutionary algorithm: a novel evolutionary algorithm based on the ecology and environments for optimization

DEFF Research Database (Denmark)

Li, Wuzhao; Wang, Lei; Cai, Xingjuan

2015-01-01

and affect each other in many ways. The relationships include competition, predation, parasitism, mutualism and pythogenesis. In this paper, we consider the five relationships between solutions to propose a co-evolutionary algorithm termed species co-evolutionary algorithm (SCEA). In SCEA, five operators...

Evolutionary Genomics of Life in (and from) the Sea

Energy Technology Data Exchange (ETDEWEB)

Boore, Jeffrey L.; Dehal, Paramvir; Fuerstenberg, Susan I.

2006-01-09

High throughput genome sequencing centers that were originally built for the Human Genome Project (Lander et al., 2001; Venter et al., 2001) have now become an engine for comparative genomics. The six largest centers alone are now producing over 150 billion nucleotides per year, more than 50 times the amount of DNA in the human genome, and nearly all of this is directed at projects that promise great insights into the pattern and processes of evolution. Unfortunately, this data is being produced at a pace far exceeding the capacity of the scientific community to provide insightful analysis, and few scientists with training and experience in evolutionary biology have played prominent roles to date. One of the consequences is that poor quality analyses are typical; for example, orthology among genes is generally determined by simple measures of sequence similarity, when this has been discredited by molecular evolutionary biologists decades ago. Here we discuss the how genomes are chosen for sequencing and how the scientific community can have input. We describe the PhIGs database and web tools (Dehal and Boore 2005a; http://PhIGs.org), which provide phylogenetic analysis of all gene families for all completely sequenced genomes and the associated 'Synteny Viewer', which allows comparisons of the relative positions of orthologous genes. This is the best tool available for inferring gene function across multiple genomes. We also describe how we have used the PhIGs methods with the whole genome sequences of a tunicate, fish, mouse, and human to conclusively demonstrate that two rounds of whole genome duplication occurred at the base of vertebrates (Dehal and Boore 2005b). This evidence is found in the large scale structure of the positions of paralogous genes that arose from duplications inferred by evolutionary analysis to have occurred at the base of vertebrates.

Novelties in the judges's selection

Directory of Open Access Journals (Sweden)

Anna-Maria Getoš

2013-01-01

Full Text Available The authors analyze the legal position of the judiciary in the separation of powers in the Republic of Croatia, as well as the procedure for the election of members of the State Judicial Council and its President, its scope and operation. The analysis covers the principle, as well as the practical and normative level, hereby especially focusing on the provisions of the ‘State Judicial Council Act’ from 2010 (ZDSV, which introduced significant novelties to the appointment procedure of judges. This is due to the fact that, according to the authors, the role of judges, appointed by the State Judicial Council, in the way of the Croatian accession to the European Union is quite significant, since the judges with their work, and how the interpretation of applicable regulations in the spirit of EU law, provide the essential convergence judiciary in Croatia with the acquis and the highest standards of the European Union. It gives a special and comprehensive view of general and special conditions in the appointment of judges for the period before and after 31 December 2012, and a comparative view on conditions of appointment of judges in continental European countries, the circle of countries, where Croatia belongs to, with special reference to legal status, scope, operation and role of the State School for the judicial officers in the process of appointing judges. Performs the analysis and outlines the procedure for appointment of judges, with special emphasis on each stage: the stage of calling the ads and collecting applications, testing stage of candidates for judges and candidates who are not judges and the decision stage on the appointment, with special emphasis on the criteria and evaluation of candidates who have been determined for the appointment, in the normative sense and practical action, which is a standardized procedure, the legal level and in essence, ZDSV, along with suggestions de lege ferenda.

The novel cytochrome c6 of chloroplasts: a case of evolutionary bricolage?

Science.gov (United States)

Howe, Christopher J; Schlarb-Ridley, Beatrix G; Wastl, Juergen; Purton, Saul; Bendall, Derek S

2006-01-01

Cytochrome c6 has long been known as a redox carrier of the thylakoid lumen of cyanobacteria and some eukaryotic algae that can substitute for plastocyanin in electron transfer. Until recently, it was widely accepted that land plants lack a cytochrome c6. However, a homologue of the protein has now been identified in several plant species together with an additional isoform in the green alga Chlamydomonas reinhardtii. This form of the protein, designated cytochrome c6A, differs from the 'conventional' cytochrome c6 in possessing a conserved insertion of 12 amino acids that includes two absolutely conserved cysteine residues. There are conflicting reports of whether cytochrome c6A can substitute for plastocyanin in photosynthetic electron transfer. The evidence for and against this is reviewed and the likely evolutionary history of cytochrome c6A is discussed. It is suggested that it has been converted from a primary role in electron transfer to one in regulation within the chloroplast, and is an example of evolutionary 'bricolage'.

Fixation Time for Evolutionary Graphs

Science.gov (United States)

Nie, Pu-Yan; Zhang, Pei-Ai

Evolutionary graph theory (EGT) is recently proposed by Lieberman et al. in 2005. EGT is successful for explaining biological evolution and some social phenomena. It is extremely important to consider the time of fixation for EGT in many practical problems, including evolutionary theory and the evolution of cooperation. This study characterizes the time to asymptotically reach fixation.

Evolutionary accounts of human behavioural diversity

Science.gov (United States)

Brown, Gillian R.; Dickins, Thomas E.; Sear, Rebecca; Laland, Kevin N.

2011-01-01

Human beings persist in an extraordinary range of ecological settings, in the process exhibiting enormous behavioural diversity, both within and between populations. People vary in their social, mating and parental behaviour and have diverse and elaborate beliefs, traditions, norms and institutions. The aim of this theme issue is to ask whether, and how, evolutionary theory can help us to understand this diversity. In this introductory article, we provide a background to the debate surrounding how best to understand behavioural diversity using evolutionary models of human behaviour. In particular, we examine how diversity has been viewed by the main subdisciplines within the human evolutionary behavioural sciences, focusing in particular on the human behavioural ecology, evolutionary psychology and cultural evolution approaches. In addition to differences in focus and methodology, these subdisciplines have traditionally varied in the emphasis placed on human universals, ecological factors and socially learned behaviour, and on how they have addressed the issue of genetic variation. We reaffirm that evolutionary theory provides an essential framework for understanding behavioural diversity within and between human populations, but argue that greater integration between the subfields is critical to developing a satisfactory understanding of diversity. PMID:21199836

Blue Tigers, Black Tapirs, & the Pied Raven of the Faroe Islands: Teaching Genetic Drift Using Real-Life Animal Examples

Science.gov (United States)

Robischon, Marcel

2015-01-01

Genetic drift is a concept of population genetics that is central to understanding evolutionary processes and aspects of conservation biology. It is frequently taught using rather abstract representations. I introduce three real-life zoological examples, based on historical and recent color morphs of tigers, tapirs, and ravens, that can complement…

Evolutionary Relevance Facilitates Visual Information Processing

Directory of Open Access Journals (Sweden)

Russell E. Jackson

2013-07-01

Full Text Available Visual search of the environment is a fundamental human behavior that perceptual load affects powerfully. Previously investigated means for overcoming the inhibitions of high perceptual load, however, generalize poorly to real-world human behavior. We hypothesized that humans would process evolutionarily relevant stimuli more efficiently than evolutionarily novel stimuli, and evolutionary relevance would mitigate the repercussions of high perceptual load during visual search. Animacy is a significant component to evolutionary relevance of visual stimuli because perceiving animate entities is time-sensitive in ways that pose significant evolutionary consequences. Participants completing a visual search task located evolutionarily relevant and animate objects fastest and with the least impact of high perceptual load. Evolutionarily novel and inanimate objects were located slowest and with the highest impact of perceptual load. Evolutionary relevance may importantly affect everyday visual information processing.

Evolutionary games on graphs

Science.gov (United States)

Szabó, György; Fáth, Gábor

2007-07-01

Game theory is one of the key paradigms behind many scientific disciplines from biology to behavioral sciences to economics. In its evolutionary form and especially when the interacting agents are linked in a specific social network the underlying solution concepts and methods are very similar to those applied in non-equilibrium statistical physics. This review gives a tutorial-type overview of the field for physicists. The first four sections introduce the necessary background in classical and evolutionary game theory from the basic definitions to the most important results. The fifth section surveys the topological complications implied by non-mean-field-type social network structures in general. The next three sections discuss in detail the dynamic behavior of three prominent classes of models: the Prisoner's Dilemma, the Rock-Scissors-Paper game, and Competing Associations. The major theme of the review is in what sense and how the graph structure of interactions can modify and enrich the picture of long term behavioral patterns emerging in evolutionary games.

Novelties on amoebiasis: A neglected tropical disease

Directory of Open Access Journals (Sweden)

Cecilia Ximénez

2011-01-01

Full Text Available In accordance with the 1997 documents of the World Health Organization (WHO, amoebiasis is defined as the infection by the protozoan parasite Entamoeba histolytica with or without clinical manifestations. The only known natural host of E. histolytica is the human with the large intestine as major target organ. This parasite has a very simple life cycle in which the infective form is the cyst, considered a resistant form of parasite: The asymptomatic cyst passers and the intestinal amoebiasis patients are the transmitters; they excrete cysts in their feces, which can contaminate food and water sources. E. histolytica sensu stricto is the potentially pathogenic species and E. dispar is a commensal non-pathogenic Entamoeba. Both species are biochemical, immunological and genetically distinct. The knowledge of both species with different pathogenic phenotypes comes from a large scientific debate during the second half of the 20 th century, which gave place to the rapid development of diagnostics technology based on molecular and immunological strategies. During the last ten years, knowledge of the new epidemiology of amoebiasis in different geographic endemic and non-endemic areas has been obtained by applying mostly molecular techniques. In the present work we highlight novelties on human infection and the disease that can help the general physician from both endemic and non-endemic countries in their medical practice, particularly, now that emigration is undoubtedly a global phenomenon that is modifying the previous geography of infectious diseases worldwide.

A Note on Evolutionary Algorithms and Its Applications

Science.gov (United States)

Bhargava, Shifali

2013-01-01

This paper introduces evolutionary algorithms with its applications in multi-objective optimization. Here elitist and non-elitist multiobjective evolutionary algorithms are discussed with their advantages and disadvantages. We also discuss constrained multiobjective evolutionary algorithms and their applications in various areas.

Some Analytical Properties of the Model for Stochastic Evolutionary Games in Finite Populations with Non-uniform Interaction Rate

International Nuclear Information System (INIS)

Quan Ji; Wang Xianjia

2013-01-01

Traditional evolutionary games assume uniform interaction rate, which means that the rate at which individuals meet and interact is independent of their strategies. But in some systems, especially biological systems, the players interact with each other discriminately. Taylor and Nowak (2006) were the first to establish the corresponding non-uniform interaction rate model by allowing the interaction rates to depend on strategies. Their model is based on replicator dynamics which assumes an infinite size population. But in reality, the number of individuals in the population is always finite, and there will be some random interference in the individuals' strategy selection process. Therefore, it is more practical to establish the corresponding stochastic evolutionary model in finite populations. In fact, the analysis of evolutionary games in a finite size population is more difficult. Just as Taylor and Nowak said in the outlook section of their paper, ''The analysis of non-uniform interaction rates should be extended to stochastic game dynamics of finite populations''. In this paper, we are exactly doing this work. We extend Taylor and Nowak's model from infinite to finite case, especially focusing on the infiuence of non-uniform connection characteristics on the evolutionary stable state of the system. We model the strategy evolutionary process of the population by a continuous ergodic Markov process. Based on the limit distribution of the process, we can give the evolutionary stable state of the system. We make a complete classification of the symmetric 2 × 2 games. For each case game, the corresponding limit distribution of the Markov-based process is given when noise intensity is small enough. In contrast with most literatures in evolutionary games using the simulation method, all our results obtained are analytical. Especially, in the dominant-case game, coexistence of the two strategies may become evolutionary stable states in our model. This result can be

A Test of Evolutionary Policing Theory with Data from Human Societies

Science.gov (United States)

Kümmerli, Rolf

2011-01-01

In social groups where relatedness among interacting individuals is low, cooperation can often only be maintained through mechanisms that repress competition among group members. Repression-of-competition mechanisms, such as policing and punishment, seem to be of particular importance in human societies, where cooperative interactions often occur among unrelated individuals. In line with this view, economic games have shown that the ability to punish defectors enforces cooperation among humans. Here, I examine a real-world example of a repression-of-competition system, the police institutions common to modern human societies. Specifically, I test evolutionary policing theory by comparing data on policing effort, per capita crime rate, and similarity (used as a proxy for genetic relatedness) among citizens across the 26 cantons of Switzerland. This comparison revealed full support for all three predictions of evolutionary policing theory. First, when controlling for policing efforts, crime rate correlated negatively with the similarity among citizens. This is in line with the prediction that high similarity results in higher levels of cooperative self-restraint (i.e. lower crime rates) because it aligns the interests of individuals. Second, policing effort correlated negatively with the similarity among citizens, supporting the prediction that more policing is required to enforce cooperation in low-similarity societies, where individuals' interests diverge most. Third, increased policing efforts were associated with reductions in crime rates, indicating that policing indeed enforces cooperation. These analyses strongly indicate that humans respond to cues of their social environment and adjust cheating and policing behaviour as predicted by evolutionary policing theory. PMID:21909429

A test of evolutionary policing theory with data from human societies.

Science.gov (United States)

Kümmerli, Rolf

2011-01-01

In social groups where relatedness among interacting individuals is low, cooperation can often only be maintained through mechanisms that repress competition among group members. Repression-of-competition mechanisms, such as policing and punishment, seem to be of particular importance in human societies, where cooperative interactions often occur among unrelated individuals. In line with this view, economic games have shown that the ability to punish defectors enforces cooperation among humans. Here, I examine a real-world example of a repression-of-competition system, the police institutions common to modern human societies. Specifically, I test evolutionary policing theory by comparing data on policing effort, per capita crime rate, and similarity (used as a proxy for genetic relatedness) among citizens across the 26 cantons of Switzerland. This comparison revealed full support for all three predictions of evolutionary policing theory. First, when controlling for policing efforts, crime rate correlated negatively with the similarity among citizens. This is in line with the prediction that high similarity results in higher levels of cooperative self-restraint (i.e. lower crime rates) because it aligns the interests of individuals. Second, policing effort correlated negatively with the similarity among citizens, supporting the prediction that more policing is required to enforce cooperation in low-similarity societies, where individuals' interests diverge most. Third, increased policing efforts were associated with reductions in crime rates, indicating that policing indeed enforces cooperation. These analyses strongly indicate that humans respond to cues of their social environment and adjust cheating and policing behaviour as predicted by evolutionary policing theory.

A test of evolutionary policing theory with data from human societies.

Directory of Open Access Journals (Sweden)

Rolf Kümmerli

Full Text Available In social groups where relatedness among interacting individuals is low, cooperation can often only be maintained through mechanisms that repress competition among group members. Repression-of-competition mechanisms, such as policing and punishment, seem to be of particular importance in human societies, where cooperative interactions often occur among unrelated individuals. In line with this view, economic games have shown that the ability to punish defectors enforces cooperation among humans. Here, I examine a real-world example of a repression-of-competition system, the police institutions common to modern human societies. Specifically, I test evolutionary policing theory by comparing data on policing effort, per capita crime rate, and similarity (used as a proxy for genetic relatedness among citizens across the 26 cantons of Switzerland. This comparison revealed full support for all three predictions of evolutionary policing theory. First, when controlling for policing efforts, crime rate correlated negatively with the similarity among citizens. This is in line with the prediction that high similarity results in higher levels of cooperative self-restraint (i.e. lower crime rates because it aligns the interests of individuals. Second, policing effort correlated negatively with the similarity among citizens, supporting the prediction that more policing is required to enforce cooperation in low-similarity societies, where individuals' interests diverge most. Third, increased policing efforts were associated with reductions in crime rates, indicating that policing indeed enforces cooperation. These analyses strongly indicate that humans respond to cues of their social environment and adjust cheating and policing behaviour as predicted by evolutionary policing theory.

Applied evolutionary economics and economic geography

NARCIS (Netherlands)

Frenken, K.

2007-01-01

Applied Evolutionary Economics and Economic Geography" aims to further advance empirical methodologies in evolutionary economics, with a special emphasis on geography and firm location. It does so by bringing together a select group of leading scholars including economists, geographers and

A deep learning and novelty detection framework for rapid phenotyping in high-content screening

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Sommer, Christoph; Hoefler, Rudolf; Samwer, Matthias; Gerlich, Daniel W.

2017-01-01

Supervised machine learning is a powerful and widely used method for analyzing high-content screening data. Despite its accuracy, efficiency, and versatility, supervised machine learning has drawbacks, most notably its dependence on a priori knowledge of expected phenotypes and time-consuming classifier training. We provide a solution to these limitations with CellCognition Explorer, a generic novelty detection and deep learning framework. Application to several large-scale screening data sets on nuclear and mitotic cell morphologies demonstrates that CellCognition Explorer enables discovery of rare phenotypes without user training, which has broad implications for improved assay development in high-content screening. PMID:28954863

Numerical Simulation of Entropy Growth for a Nonlinear Evolutionary Model of Random Markets

Directory of Open Access Journals (Sweden)

Mahdi Keshtkar

2016-01-01

Full Text Available In this communication, the generalized continuous economic model for random markets is revisited. In this model for random markets, agents trade by pairs and exchange their money in a random and conservative way. They display the exponential wealth distribution as asymptotic equilibrium, independently of the effectiveness of the transactions and of the limitation of the total wealth. In the current work, entropy of mentioned model is defined and then some theorems on entropy growth of this evolutionary problem are given. Furthermore, the entropy increasing by simulation on some numerical examples is verified.

Approaches to Macroevolution: 1. General Concepts and Origin of Variation.

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Jablonski, David

2017-01-01

Approaches to macroevolution require integration of its two fundamental components, i.e. the origin and the sorting of variation, in a hierarchical framework. Macroevolution occurs in multiple currencies that are only loosely correlated, notably taxonomic diversity, morphological disparity, and functional variety. The origin of variation within this conceptual framework is increasingly understood in developmental terms, with the semi-hierarchical structure of gene regulatory networks (GRNs, used here in a broad sense incorporating not just the genetic circuitry per se but the factors controlling the timing and location of gene expression and repression), the non-linear relation between magnitude of genetic change and the phenotypic results, the evolutionary potential of co-opting existing GRNs, and developmental responsiveness to nongenetic signals (i.e. epigenetics and plasticity), all requiring modification of standard microevolutionary models, and rendering difficult any simple definition of evolutionary novelty. The developmental factors underlying macroevolution create anisotropic probabilities-i.e., an uneven density distribution-of evolutionary change around any given phenotypic starting point, and the potential for coordinated changes among traits that can accommodate change via epigenetic mechanisms. From this standpoint, "punctuated equilibrium" and "phyletic gradualism" simply represent two cells in a matrix of evolutionary models of phenotypic change, and the origin of trends and evolutionary novelty are not simply functions of ecological opportunity. Over long timescales, contingency becomes especially important, and can be viewed in terms of macroevolutionary lags (the temporal separation between the origin of a trait or clade and subsequent diversification); such lags can arise by several mechanisms: as geological or phylogenetic artifacts, or when diversifications require synergistic interactions among traits, or between traits and external events

Diversity-Guided Evolutionary Algorithms

DEFF Research Database (Denmark)

Ursem, Rasmus Kjær

2002-01-01

Population diversity is undoubtably a key issue in the performance of evolutionary algorithms. A common hypothesis is that high diversity is important to avoid premature convergence and to escape local optima. Various diversity measures have been used to analyze algorithms, but so far few...... algorithms have used a measure to guide the search. The diversity-guided evolutionary algorithm (DGEA) uses the wellknown distance-to-average-point measure to alternate between phases of exploration (mutation) and phases of exploitation (recombination and selection). The DGEA showed remarkable results...

Phylogenetic inference with weighted codon evolutionary distances.

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Criscuolo, Alexis; Michel, Christian J

2009-04-01

We develop a new approach to estimate a matrix of pairwise evolutionary distances from a codon-based alignment based on a codon evolutionary model. The method first computes a standard distance matrix for each of the three codon positions. Then these three distance matrices are weighted according to an estimate of the global evolutionary rate of each codon position and averaged into a unique distance matrix. Using a large set of both real and simulated codon-based alignments of nucleotide sequences, we show that this approach leads to distance matrices that have a significantly better treelikeness compared to those obtained by standard nucleotide evolutionary distances. We also propose an alternative weighting to eliminate the part of the noise often associated with some codon positions, particularly the third position, which is known to induce a fast evolutionary rate. Simulation results show that fast distance-based tree reconstruction algorithms on distance matrices based on this codon position weighting can lead to phylogenetic trees that are at least as accurate as, if not better, than those inferred by maximum likelihood. Finally, a well-known multigene dataset composed of eight yeast species and 106 codon-based alignments is reanalyzed and shows that our codon evolutionary distances allow building a phylogenetic tree which is similar to those obtained by non-distance-based methods (e.g., maximum parsimony and maximum likelihood) and also significantly improved compared to standard nucleotide evolutionary distance estimates.

MMN and novelty P3 in coma and other altered states of consciousness: a review.

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Morlet, Dominique; Fischer, Catherine

2014-07-01

In recent decades, there has been a growing interest in the assessment of patients in altered states of consciousness. There is a need for accurate and early prediction of awakening and recovery from coma. Neurophysiological assessment of coma was once restricted to brainstem auditory and primary cortex somatosensory evoked potentials elicited in the 30 ms range, which have both shown good predictive value for poor coma outcome only. In this paper, we review how passive auditory oddball paradigms including deviant and novel sounds have proved their efficiency in assessing brain function at a higher level, without requiring the patient's active involvement, thus providing an enhanced tool for the prediction of coma outcome. The presence of an MMN in response to deviant stimuli highlights preserved automatic sensory memory processes. Recorded during coma, MMN has shown high specificity as a predictor of recovery of consciousness. The presence of a novelty P3 in response to the subject's own first name presented as a novel (rare) stimulus has shown a good correlation with coma awakening. There is now a growing interest in the search for markers of consciousness, if there are any, in unresponsive patients (chronic vegetative or minimally conscious states). We discuss the different ERP patterns observed in these patients. The presence of novelty P3, including parietal components and possibly followed by a late parietal positivity, raises the possibility that some awareness processes are at work in these unresponsive patients.

Evolutionary Dynamics of Collective Action in Structured Populations

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Santos, Marta Daniela de Almeida

The pervasiveness of cooperation in Nature is not easily explained. If evolution is characterized by competition and survival of the fittest, why should selfish individuals cooperate with each other? Evolutionary Game Theory (EGT) provides a suitable mathematical framework to study this problem, central to many areas of science. Conventionally, interactions between individuals are modeled in terms of one-shot, symmetric 2-Person Dilemmas of Cooperation, but many real-life situations involve decisions within groups with more than 2 individuals, which are best-dealt in the framework of N-Person games. In this Thesis, we investigate the evolutionary dynamics of two paradigmatic collective social dilemmas - the N-Person Prisoner's Dilemma (NPD) and the N-Person Snowdrift Game (NSG) on structured populations, modeled by networks with diverse topological properties. Cooperative strategies are just one example of the many traits that can be transmitted on social networks. Several recent studies based on empirical evidence from a medical database have suggested the existence of a 3 degrees of influence rule, according to which not only our "friends", but also our friends' friends, and our friends' friends' friends, have a non-trivial influence on our decisions. We investigate the degree of peer influence that emerges from the spread of cooperative strategies, opinions and diseases on populations with distinct underlying networks of contacts. Our results show that networks naturally entangle individuals into interactions of many-body nature and that for each network class considered different processes lead to identical degrees of influence. None

Lengths of Orthologous Prokaryotic Proteins Are Affected by Evolutionary Factors

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Tatiana Tatarinova

2015-01-01

Full Text Available Proteins of the same functional family (for example, kinases may have significantly different lengths. It is an open question whether such variation in length is random or it appears as a response to some unknown evolutionary driving factors. The main purpose of this paper is to demonstrate existence of factors affecting prokaryotic gene lengths. We believe that the ranking of genomes according to lengths of their genes, followed by the calculation of coefficients of association between genome rank and genome property, is a reasonable approach in revealing such evolutionary driving factors. As we demonstrated earlier, our chosen approach, Bubble-sort, combines stability, accuracy, and computational efficiency as compared to other ranking methods. Application of Bubble Sort to the set of 1390 prokaryotic genomes confirmed that genes of Archaeal species are generally shorter than Bacterial ones. We observed that gene lengths are affected by various factors: within each domain, different phyla have preferences for short or long genes; thermophiles tend to have shorter genes than the soil-dwellers; halophiles tend to have longer genes. We also found that species with overrepresentation of cytosines and guanines in the third position of the codon (GC3 content tend to have longer genes than species with low GC3 content.

Lengths of Orthologous Prokaryotic Proteins Are Affected by Evolutionary Factors.

Science.gov (United States)

Tatarinova, Tatiana; Salih, Bilal; Dien Bard, Jennifer; Cohen, Irit; Bolshoy, Alexander

2015-01-01

Proteins of the same functional family (for example, kinases) may have significantly different lengths. It is an open question whether such variation in length is random or it appears as a response to some unknown evolutionary driving factors. The main purpose of this paper is to demonstrate existence of factors affecting prokaryotic gene lengths. We believe that the ranking of genomes according to lengths of their genes, followed by the calculation of coefficients of association between genome rank and genome property, is a reasonable approach in revealing such evolutionary driving factors. As we demonstrated earlier, our chosen approach, Bubble-sort, combines stability, accuracy, and computational efficiency as compared to other ranking methods. Application of Bubble Sort to the set of 1390 prokaryotic genomes confirmed that genes of Archaeal species are generally shorter than Bacterial ones. We observed that gene lengths are affected by various factors: within each domain, different phyla have preferences for short or long genes; thermophiles tend to have shorter genes than the soil-dwellers; halophiles tend to have longer genes. We also found that species with overrepresentation of cytosines and guanines in the third position of the codon (GC3 content) tend to have longer genes than species with low GC3 content.

Evolutionary perspectives on ageing.

Science.gov (United States)

Reichard, Martin

2017-10-01

From an evolutionary perspective, ageing is a decrease in fitness with chronological age - expressed by an increase in mortality risk and/or decline in reproductive success and mediated by deterioration of functional performance. While this makes ageing intuitively paradoxical - detrimental to individual fitness - evolutionary theory offers answers as to why ageing has evolved. In this review, I first briefly examine the classic evolutionary theories of ageing and their empirical tests, and highlight recent findings that have advanced our understanding of the evolution of ageing (condition-dependent survival, positive pleiotropy). I then provide an overview of recent theoretical extensions and modifications that accommodate those new discoveries. I discuss the role of indeterminate (asymptotic) growth for lifetime increases in fecundity and ageing trajectories. I outline alternative views that challenge a universal existence of senescence - namely the lack of a germ-soma distinction and the ability of tissue replacement and retrogression to younger developmental stages in modular organisms. I argue that rejuvenation at the organismal level is plausible, but includes a return to a simple developmental stage. This may exempt a particular genotype from somatic defects but, correspondingly, removes any information acquired during development. A resolution of the question of whether a rejuvenated individual is the same entity is central to the recognition of whether current evolutionary theories of ageing, with their extensions and modifications, can explain the patterns of ageing across the Tree of Life. Copyright © 2017 Elsevier Ltd. All rights reserved.

Interpreting Evolutionary Diagrams: When Topology and Process Conflict

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Catley, Kefyn M.; Novick, Laura R.; Shade, Courtney K.

2010-01-01

The authors argue that some diagrams in biology textbooks and the popular press presented as depicting evolutionary relationships suggest an inappropriate (anagenic) conception of evolutionary history. The goal of this research was to provide baseline data that begin to document how college students conceptualize the evolutionary relationships…

Using Evolutionary Theory to Guide Mental Health Research.

Science.gov (United States)

Durisko, Zachary; Mulsant, Benoit H; McKenzie, Kwame; Andrews, Paul W

2016-03-01

Evolutionary approaches to medicine can shed light on the origins and etiology of disease. Such an approach may be especially useful in psychiatry, which frequently addresses conditions with heterogeneous presentation and unknown causes. We review several previous applications of evolutionary theory that highlight the ways in which psychiatric conditions may persist despite and because of natural selection. One lesson from the evolutionary approach is that some conditions currently classified as disorders (because they cause distress and impairment) may actually be caused by functioning adaptations operating "normally" (as designed by natural selection). Such conditions suggest an alternative illness model that may generate alternative intervention strategies. Thus, the evolutionary approach suggests that psychiatry should sometimes think differently about distress and impairment. The complexity of the human brain, including normal functioning and potential for dysfunctions, has developed over evolutionary time and has been shaped by natural selection. Understanding the evolutionary origins of psychiatric conditions is therefore a crucial component to a complete understanding of etiology. © The Author(s) 2016.

Evolutionary engineering of industrial microorganisms-strategies and applications.

Science.gov (United States)

Zhu, Zhengming; Zhang, Juan; Ji, Xiaomei; Fang, Zhen; Wu, Zhimeng; Chen, Jian; Du, Guocheng

2018-06-01

Microbial cells have been widely used in the industry to obtain various biochemical products, and evolutionary engineering is a common method in biological research to improve their traits, such as high environmental tolerance and improvement of product yield. To obtain better integrate functions of microbial cells, evolutionary engineering combined with other biotechnologies have attracted more attention in recent years. Classical laboratory evolution has been proven effective to letting more beneficial mutations occur in different genes but also has some inherent limitations such as a long evolutionary period and uncontrolled mutation frequencies. However, recent studies showed that some new strategies may gradually overcome these limitations. In this review, we summarize the evolutionary strategies commonly used in industrial microorganisms and discuss the combination of evolutionary engineering with other biotechnologies such as systems biology and inverse metabolic engineering. Finally, we prospect the importance and application prospect of evolutionary engineering as a powerful tool especially in optimization of industrial microbial cell factories.

Democratizing evolutionary biology, lessons from insects

DEFF Research Database (Denmark)

Dunn, Robert Roberdeau; Beasley, DeAnna E.

2016-01-01

The engagement of the public in the scientific process is an old practice. Yet with recent advances in technology, the role of the citizen scientist in studying evolutionary processes has increased. Insects provide ideal models for understanding these evolutionary processes at large scales. This ...

Evolutionary theory and the naturalist fallacy

DEFF Research Database (Denmark)

Grodal, Torben Kragh

2008-01-01

that great work of art are also automatically fitness-enhancing in the present day environment, at that there are simple correllations between whether a work of art has a high aesthetic value and whether it is fitness-enhancing or not.  Keywords :  Evolutionary aesthetics, film theory, literary theory......The article is an invited response to a target article by Joseph Carroll entitled "An evolutionary paradigm for literary study". It argues that the target article  misuse the fact that works of art are based on adaptations that were fitness-enhancing in the era of evolutionary adaptations to claim...

Mapping of Technological Opportunities-Labyrinth Seal Example

Science.gov (United States)

Clarke, Dana W., Sr.

2006-01-01

All technological systems evolve based on evolutionary sequences that have repeated throughout history and can be abstracted from the history of technology and patents. These evolutionary sequences represent objective patterns and provide considerable insights that can be used to proactively model future seal concepts. This presentation provides an overview of how to map seal technology into the future using a labyrinth seal example. The mapping process delivers functional descriptions of sequential changes in market/consumer demand, from today s current paradigm to the next major paradigm shift. The future paradigm is developed according to a simple formula: the future paradigm is free of all flaws associated with the current paradigm; it is as far into the future as we can see. Although revolutionary, the vision of the future paradigm is typically not immediately or completely realizable nor is it normally seen as practical. There are several reasons that prevent immediate and complete practical application, such as: 1) Some of the required technological or business resources and knowledge not being available; 2) Availability of other technological or business resources are limited; and/or 3) Some necessary knowledge has not been completely developed. These factors tend to drive the Total Cost of Ownership or Utilization out of an acceptable range and revealing the reasons for the high Total Cost of Ownership or Utilization which provides a clear understanding of research opportunities essential for future developments and defines the current limits of the immediately achievable improvements. The typical roots of high Total Cost of Ownership or Utilization lie in the limited availability or even the absence of essential resources and knowledge necessary for its realization. In order to overcome this obstacle, step-by-step modification of the current paradigm is pursued to evolve from the current situation toward the ideal future, i.e., evolution rather than

Evolutionary public health: introducing the concept.

Science.gov (United States)

Wells, Jonathan C K; Nesse, Randolph M; Sear, Rebecca; Johnstone, Rufus A; Stearns, Stephen C

2017-07-29

The emerging discipline of evolutionary medicine is breaking new ground in understanding why people become ill. However, the value of evolutionary analyses of human physiology and behaviour is only beginning to be recognised in the field of public health. Core principles come from life history theory, which analyses the allocation of finite amounts of energy between four competing functions-maintenance, growth, reproduction, and defence. A central tenet of evolutionary theory is that organisms are selected to allocate energy and time to maximise reproductive success, rather than health or longevity. Ecological interactions that influence mortality risk, nutrient availability, and pathogen burden shape energy allocation strategies throughout the life course, thereby affecting diverse health outcomes. Public health interventions could improve their own effectiveness by incorporating an evolutionary perspective. In particular, evolutionary approaches offer new opportunities to address the complex challenges of global health, in which populations are differentially exposed to the metabolic consequences of poverty, high fertility, infectious diseases, and rapid changes in nutrition and lifestyle. The effect of specific interventions is predicted to depend on broader factors shaping life expectancy. Among the important tools in this approach are mathematical models, which can explore probable benefits and limitations of interventions in silico, before their implementation in human populations. Copyright © 2017 Elsevier Ltd. All rights reserved.

The evolutionary ecology of molecular replicators.

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Nee, Sean

2016-08-01

By reasonable criteria, life on the Earth consists mainly of molecular replicators. These include viruses, transposons, transpovirons, coviruses and many more, with continuous new discoveries like Sputnik Virophage. Their study is inherently multidisciplinary, spanning microbiology, genetics, immunology and evolutionary theory, and the current view is that taking a unified approach has great power and promise. We support this with a new, unified, model of their evolutionary ecology, using contemporary evolutionary theory coupling the Price equation with game theory, studying the consequences of the molecular replicators' promiscuous use of each others' gene products for their natural history and evolutionary ecology. Even at this simple expository level, we can make a firm prediction of a new class of replicators exploiting viruses such as lentiviruses like SIVs, a family which includes HIV: these have been explicitly stated in the primary literature to be non-existent. Closely connected to this departure is the view that multicellular organism immunology is more about the management of chronic infections rather than the elimination of acute ones and new understandings emerging are changing our view of the kind of theatre we ourselves provide for the evolutionary play of molecular replicators. This study adds molecular replicators to bacteria in the emerging field of sociomicrobiology.

Multiobjective Multifactorial Optimization in Evolutionary Multitasking.

Science.gov (United States)

Gupta, Abhishek; Ong, Yew-Soon; Feng, Liang; Tan, Kay Chen

2016-05-03

In recent decades, the field of multiobjective optimization has attracted considerable interest among evolutionary computation researchers. One of the main features that makes evolutionary methods particularly appealing for multiobjective problems is the implicit parallelism offered by a population, which enables simultaneous convergence toward the entire Pareto front. While a plethora of related algorithms have been proposed till date, a common attribute among them is that they focus on efficiently solving only a single optimization problem at a time. Despite the known power of implicit parallelism, seldom has an attempt been made to multitask, i.e., to solve multiple optimization problems simultaneously. It is contended that the notion of evolutionary multitasking leads to the possibility of automated transfer of information across different optimization exercises that may share underlying similarities, thereby facilitating improved convergence characteristics. In particular, the potential for automated transfer is deemed invaluable from the standpoint of engineering design exercises where manual knowledge adaptation and reuse are routine. Accordingly, in this paper, we present a realization of the evolutionary multitasking paradigm within the domain of multiobjective optimization. The efficacy of the associated evolutionary algorithm is demonstrated on some benchmark test functions as well as on a real-world manufacturing process design problem from the composites industry.

Evolutionary heritage influences Amazon tree ecology

Science.gov (United States)

Coelho de Souza, Fernanda; Dexter, Kyle G.; Phillips, Oliver L.; Brienen, Roel J. W.; Chave, Jerome; Galbraith, David R.; Lopez Gonzalez, Gabriela; Monteagudo Mendoza, Abel; Pennington, R. Toby; Poorter, Lourens; Alexiades, Miguel; Álvarez-Dávila, Esteban; Andrade, Ana; Aragão, Luis E. O. C.; Araujo-Murakami, Alejandro; Arets, Eric J. M. M.; Aymard C, Gerardo A.; Baraloto, Christopher; Barroso, Jorcely G.; Bonal, Damien; Boot, Rene G. A.; Camargo, José L. C.; Comiskey, James A.; Valverde, Fernando Cornejo; de Camargo, Plínio B.; Di Fiore, Anthony; Erwin, Terry L.; Feldpausch, Ted R.; Ferreira, Leandro; Fyllas, Nikolaos M.; Gloor, Emanuel; Herault, Bruno; Herrera, Rafael; Higuchi, Niro; Honorio Coronado, Eurídice N.; Killeen, Timothy J.; Laurance, William F.; Laurance, Susan; Lloyd, Jon; Lovejoy, Thomas E.; Malhi, Yadvinder; Maracahipes, Leandro; Marimon, Beatriz S.; Marimon-Junior, Ben H.; Mendoza, Casimiro; Morandi, Paulo; Neill, David A.; Vargas, Percy Núñez; Oliveira, Edmar A.; Lenza, Eddie; Palacios, Walter A.; Peñuela-Mora, Maria C.; Pipoly, John J.; Pitman, Nigel C. A.; Prieto, Adriana; Quesada, Carlos A.; Ramirez-Angulo, Hirma; Rudas, Agustin; Ruokolainen, Kalle; Salomão, Rafael P.; Silveira, Marcos; ter Steege, Hans; Thomas-Caesar, Raquel; van der Hout, Peter; van der Heijden, Geertje M. F.; van der Meer, Peter J.; Vasquez, Rodolfo V.; Vieira, Simone A.; Vilanova, Emilio; Vos, Vincent A.; Wang, Ophelia; Young, Kenneth R.; Zagt, Roderick J.; Baker, Timothy R.

2016-01-01

Lineages tend to retain ecological characteristics of their ancestors through time. However, for some traits, selection during evolutionary history may have also played a role in determining trait values. To address the relative importance of these processes requires large-scale quantification of traits and evolutionary relationships among species. The Amazonian tree flora comprises a high diversity of angiosperm lineages and species with widely differing life-history characteristics, providing an excellent system to investigate the combined influences of evolutionary heritage and selection in determining trait variation. We used trait data related to the major axes of life-history variation among tropical trees (e.g. growth and mortality rates) from 577 inventory plots in closed-canopy forest, mapped onto a phylogenetic hypothesis spanning more than 300 genera including all major angiosperm clades to test for evolutionary constraints on traits. We found significant phylogenetic signal (PS) for all traits, consistent with evolutionarily related genera having more similar characteristics than expected by chance. Although there is also evidence for repeated evolution of pioneer and shade tolerant life-history strategies within independent lineages, the existence of significant PS allows clearer predictions of the links between evolutionary diversity, ecosystem function and the response of tropical forests to global change. PMID:27974517

Evolutionary heritage influences Amazon tree ecology.

Science.gov (United States)

Coelho de Souza, Fernanda; Dexter, Kyle G; Phillips, Oliver L; Brienen, Roel J W; Chave, Jerome; Galbraith, David R; Lopez Gonzalez, Gabriela; Monteagudo Mendoza, Abel; Pennington, R Toby; Poorter, Lourens; Alexiades, Miguel; Álvarez-Dávila, Esteban; Andrade, Ana; Aragão, Luis E O C; Araujo-Murakami, Alejandro; Arets, Eric J M M; Aymard C, Gerardo A; Baraloto, Christopher; Barroso, Jorcely G; Bonal, Damien; Boot, Rene G A; Camargo, José L C; Comiskey, James A; Valverde, Fernando Cornejo; de Camargo, Plínio B; Di Fiore, Anthony; Elias, Fernando; Erwin, Terry L; Feldpausch, Ted R; Ferreira, Leandro; Fyllas, Nikolaos M; Gloor, Emanuel; Herault, Bruno; Herrera, Rafael; Higuchi, Niro; Honorio Coronado, Eurídice N; Killeen, Timothy J; Laurance, William F; Laurance, Susan; Lloyd, Jon; Lovejoy, Thomas E; Malhi, Yadvinder; Maracahipes, Leandro; Marimon, Beatriz S; Marimon-Junior, Ben H; Mendoza, Casimiro; Morandi, Paulo; Neill, David A; Vargas, Percy Núñez; Oliveira, Edmar A; Lenza, Eddie; Palacios, Walter A; Peñuela-Mora, Maria C; Pipoly, John J; Pitman, Nigel C A; Prieto, Adriana; Quesada, Carlos A; Ramirez-Angulo, Hirma; Rudas, Agustin; Ruokolainen, Kalle; Salomão, Rafael P; Silveira, Marcos; Stropp, Juliana; Ter Steege, Hans; Thomas-Caesar, Raquel; van der Hout, Peter; van der Heijden, Geertje M F; van der Meer, Peter J; Vasquez, Rodolfo V; Vieira, Simone A; Vilanova, Emilio; Vos, Vincent A; Wang, Ophelia; Young, Kenneth R; Zagt, Roderick J; Baker, Timothy R

2016-12-14

Lineages tend to retain ecological characteristics of their ancestors through time. However, for some traits, selection during evolutionary history may have also played a role in determining trait values. To address the relative importance of these processes requires large-scale quantification of traits and evolutionary relationships among species. The Amazonian tree flora comprises a high diversity of angiosperm lineages and species with widely differing life-history characteristics, providing an excellent system to investigate the combined influences of evolutionary heritage and selection in determining trait variation. We used trait data related to the major axes of life-history variation among tropical trees (e.g. growth and mortality rates) from 577 inventory plots in closed-canopy forest, mapped onto a phylogenetic hypothesis spanning more than 300 genera including all major angiosperm clades to test for evolutionary constraints on traits. We found significant phylogenetic signal (PS) for all traits, consistent with evolutionarily related genera having more similar characteristics than expected by chance. Although there is also evidence for repeated evolution of pioneer and shade tolerant life-history strategies within independent lineages, the existence of significant PS allows clearer predictions of the links between evolutionary diversity, ecosystem function and the response of tropical forests to global change. © 2016 The Authors.

Comprehensive behavioral analysis of RNG105 (Caprin1) heterozygous mice: Reduced social interaction and attenuated response to novelty

Science.gov (United States)

Ohashi, Rie; Takao, Keizo; Miyakawa, Tsuyoshi; Shiina, Nobuyuki

2016-01-01

RNG105 (also known as Caprin1) is a major RNA-binding protein in neuronal RNA granules, and is responsible for mRNA transport to dendrites and neuronal network formation. A recent study reported that a heterozygous mutation in the Rng105 gene was found in an autism spectrum disorder (ASD) patient, but it remains unclear whether there is a causal relation between RNG105 deficiency and ASD. Here, we subjected Rng105+/− mice to a comprehensive behavioral test battery, and revealed the influence of RNG105 deficiency on mouse behavior. Rng105+/− mice exhibited a reduced sociality in a home cage and a weak preference for social novelty. Consistently, the Rng105+/− mice also showed a weak preference for novel objects and novel place patterns. Furthermore, although the Rng105+/− mice exhibited normal memory acquisition, they tended to have relative difficulty in reversal learning in the spatial reference tasks. These findings suggest that the RNG105 heterozygous knockout leads to a reduction in sociality, response to novelty and flexibility in learning, which are implicated in ASD-like behavior. PMID:26865403

Evolutionary cell biology: two origins, one objective.

Science.gov (United States)

Lynch, Michael; Field, Mark C; Goodson, Holly V; Malik, Harmit S; Pereira-Leal, José B; Roos, David S; Turkewitz, Aaron P; Sazer, Shelley

2014-12-02

All aspects of biological diversification ultimately trace to evolutionary modifications at the cellular level. This central role of cells frames the basic questions as to how cells work and how cells come to be the way they are. Although these two lines of inquiry lie respectively within the traditional provenance of cell biology and evolutionary biology, a comprehensive synthesis of evolutionary and cell-biological thinking is lacking. We define evolutionary cell biology as the fusion of these two eponymous fields with the theoretical and quantitative branches of biochemistry, biophysics, and population genetics. The key goals are to develop a mechanistic understanding of general evolutionary processes, while specifically infusing cell biology with an evolutionary perspective. The full development of this interdisciplinary field has the potential to solve numerous problems in diverse areas of biology, including the degree to which selection, effectively neutral processes, historical contingencies, and/or constraints at the chemical and biophysical levels dictate patterns of variation for intracellular features. These problems can now be examined at both the within- and among-species levels, with single-cell methodologies even allowing quantification of variation within genotypes. Some results from this emerging field have already had a substantial impact on cell biology, and future findings will significantly influence applications in agriculture, medicine, environmental science, and synthetic biology.

How to Identify and Interpret Evolutionary Tree Diagrams

Science.gov (United States)

Kong, Yi; Anderson, Trevor; Pelaez, Nancy

2016-01-01

Evolutionary trees are key tools for modern biology and are commonly portrayed in textbooks to promote learning about biological evolution. However, many people have difficulty in understanding what evolutionary trees are meant to portray. In fact, some ideas that current professional biologists depict with evolutionary trees are neither clearly…

Evolutionary biology of bacterial and fungal pathogens

National Research Council Canada - National Science Library

Baquero, F

2008-01-01

... and Evolutionary Dynamics of Pathogens * 21 Keith A. Crandall and Marcos Pérez-Losada II. Evolutionary Genetics of Microbial Pathogens 4. Environmental and Social Influences on Infectious Disea...

An Educational Way of Dealing with Tunneling, Motivation to Novelties, and Creative Mindies in 13-16 Years of Age.

Science.gov (United States)

Laasonen, Raimo J.

The objective of this study was to inquire if tunneling of mind, motivation to novelties, and creative mindies in 4 age groups (13, 14, 15, and 16, years of age) have dynamic relationships. A creative mindy is a new organized mind shape not previously occurring. The subjects were 93 pupils of a secondary comprehensive school. Questionnaires were…

Regional systems of innovation: an evolutionary perspective

OpenAIRE

P Cooke; M G Uranga; G Etxebarria

1998-01-01

The authors develop the concept of regional systems of innovation and relate it to preexisting research on national systems of innovation. They argue that work conducted in the 'new regional science' field is complementary to systems of innovation approaches. They seek to link new regional work to evolutionary economics, and argue for the development of evolutionary regional science. Common elements of interest to evolutionary innovation research and new regional science are important in unde...

Developmental and evolutionary novelty in the serrated teeth of theropod dinosaurs.

Science.gov (United States)

Brink, K S; Reisz, R R; LeBlanc, A R H; Chang, R S; Lee, Y C; Chiang, C C; Huang, T; Evans, D C

2015-07-28

Tooth morphology and development can provide valuable insights into the feeding behaviour and evolution of extinct organisms. The teeth of Theropoda, the only clade of predominantly predatory dinosaurs, are characterized by ziphodonty, the presence of serrations (denticles) on their cutting edges. Known today only in varanid lizards, ziphodonty is much more pervasive in the fossil record. Here we present the first model for the development of ziphodont teeth in theropods through histological, SEM, and SR-FTIR analyses, revealing that structures previously hypothesized to prevent tooth breakage instead first evolved to shape and maintain the characteristic denticles through the life of the tooth. We show that this novel complex of dental morphology and tissues characterizes Theropoda, with the exception of species with modified feeding behaviours, suggesting that these characters are important for facilitating the hypercarnivorous diet of most theropods. This adaptation may have played an important role in the initial radiation and subsequent success of theropods as terrestrial apex predators.

Is there still room for novelty, in histochemical papers?

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Carlo Pellicciari

2016-12-01

Full Text Available Histochemistry continues to be widely applied in biomedical research, being nowadays mostly addressed to detect and locate single molecules or molecular complexes inside cells and tissues, and to relate structural organization and function at the high resolution of the more advanced microscopical techniques. In the attempt to see whether histochemical novelties may be found in the recent literature, the articles published in the European Journal of Histochemistry in the period 2014-2016 have been reviewed. In the majority of the published papers, standardized methods have been preferred by scientists to make their results reliably comparable with the data in the literature, but  many papers (approximately one fourth of the published articles described novel histochemical methods and procedures.  It is worth noting that there is a growing interest for minimally-invasive in vivo techniques (magnetic resonance imaging, autofluorescence spectroscopy which may parallel conventional  histochemical analyses to obtain information not only on the morphological features of living organs and tissues, but also on their functional, biophysical and molecular characteristics. Thanks to this unceasing methodological refinement, histochemistry will continue to provide innovative applications in the biomedical field.

Evolutionary robotics

Indian Academy of Sciences (India)

In evolutionary robotics, a suitable robot control system is developed automatically through evolution due to the interactions between the robot and its environment. It is a complicated task, as the robot and the environment constitute a highly dynamical system. Several methods have been tried by various investigators to ...

What serial homologs can tell us about the origin of insect wings [version 1; referees: 2 approved

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Yoshinori Tomoyasu

2017-03-01

Full Text Available Although the insect wing is a textbook example of morphological novelty, the origin of insect wings remains a mystery and is regarded as a chief conundrum in biology. Centuries of debates have culminated into two prominent hypotheses: the tergal origin hypothesis and the pleural origin hypothesis. However, between these two hypotheses, there is little consensus in regard to the origin tissue of the wing as well as the evolutionary route from the origin tissue to the functional flight device. Recent evolutionary developmental (evo-devo studies have shed new light on the origin of insect wings. A key concept in these studies is “serial homology”. In this review, we discuss how the wing serial homologs identified in recent evo-devo studies have provided a new angle through which this century-old conundrum can be explored. We also review what we have learned so far from wing serial homologs and discuss what we can do to go beyond simply identifying wing serial homologs and delve further into the developmental and genetic mechanisms that have facilitated the evolution of insect wings.

Evolutionary mysteries in meiosis.

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Lenormand, Thomas; Engelstädter, Jan; Johnston, Susan E; Wijnker, Erik; Haag, Christoph R

2016-10-19

Meiosis is a key event of sexual life cycles in eukaryotes. Its mechanistic details have been uncovered in several model organisms, and most of its essential features have received various and often contradictory evolutionary interpretations. In this perspective, we present an overview of these often 'weird' features. We discuss the origin of meiosis (origin of ploidy reduction and recombination, two-step meiosis), its secondary modifications (in polyploids or asexuals, inverted meiosis), its importance in punctuating life cycles (meiotic arrests, epigenetic resetting, meiotic asymmetry, meiotic fairness) and features associated with recombination (disjunction constraints, heterochiasmy, crossover interference and hotspots). We present the various evolutionary scenarios and selective pressures that have been proposed to account for these features, and we highlight that their evolutionary significance often remains largely mysterious. Resolving these mysteries will likely provide decisive steps towards understanding why sex and recombination are found in the majority of eukaryotes.This article is part of the themed issue 'Weird sex: the underappreciated diversity of sexual reproduction'. © 2016 The Author(s).

Application of artificial intelligence in Geodesy - A review of theoretical foundations and practical examples

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Reiterer, Alexander; Egly, Uwe; Vicovac, Tanja; Mai, Enrico; Moafipoor, Shahram; Grejner-Brzezinska, Dorota A.; Toth, Charles K.

2010-12-01

Artificial Intelligence (AI) is one of the key technologies in many of today's novel applications. It is used to add knowledge and reasoning to systems. This paper illustrates a review of AI methods including examples of their practical application in Geodesy like data analysis, deformation analysis, navigation, network adjustment, and optimization of complex measurement procedures. We focus on three examples, namely, a geo-risk assessment system supported by a knowledge-base, an intelligent dead reckoning personal navigator, and evolutionary strategies for the determination of Earth gravity field parameters. Some of the authors are members of IAG Sub-Commission 4.2 - Working Group 4.2.3, which has the main goal to study and report on the application of AI in Engineering Geodesy.

Evolutionary Computation Techniques for Predicting Atmospheric Corrosion

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Amine Marref

2013-01-01

Full Text Available Corrosion occurs in many engineering structures such as bridges, pipelines, and refineries and leads to the destruction of materials in a gradual manner and thus shortening their lifespan. It is therefore crucial to assess the structural integrity of engineering structures which are approaching or exceeding their designed lifespan in order to ensure their correct functioning, for example, carrying ability and safety. An understanding of corrosion and an ability to predict corrosion rate of a material in a particular environment plays a vital role in evaluating the residual life of the material. In this paper we investigate the use of genetic programming and genetic algorithms in the derivation of corrosion-rate expressions for steel and zinc. Genetic programming is used to automatically evolve corrosion-rate expressions while a genetic algorithm is used to evolve the parameters of an already engineered corrosion-rate expression. We show that both evolutionary techniques yield corrosion-rate expressions that have good accuracy.

Evolutionary squeaky wheel optimization: a new framework for analysis.

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Li, Jingpeng; Parkes, Andrew J; Burke, Edmund K

2011-01-01

Squeaky wheel optimization (SWO) is a relatively new metaheuristic that has been shown to be effective for many real-world problems. At each iteration SWO does a complete construction of a solution starting from the empty assignment. Although the construction uses information from previous iterations, the complete rebuilding does mean that SWO is generally effective at diversification but can suffer from a relatively weak intensification. Evolutionary SWO (ESWO) is a recent extension to SWO that is designed to improve the intensification by keeping the good components of solutions and only using SWO to reconstruct other poorer components of the solution. In such algorithms a standard challenge is to understand how the various parameters affect the search process. In order to support the future study of such issues, we propose a formal framework for the analysis of ESWO. The framework is based on Markov chains, and the main novelty arises because ESWO moves through the space of partial assignments. This makes it significantly different from the analyses used in local search (such as simulated annealing) which only move through complete assignments. Generally, the exact details of ESWO will depend on various heuristics; so we focus our approach on a case of ESWO that we call ESWO-II and that has probabilistic as opposed to heuristic selection and construction operators. For ESWO-II, we study a simple problem instance and explicitly compute the stationary distribution probability over the states of the search space. We find interesting properties of the distribution. In particular, we find that the probabilities of states generally, but not always, increase with their fitness. This nonmonotonocity is quite different from the monotonicity expected in algorithms such as simulated annealing.

Spatial Evolutionary Games of Interaction among Generic Cancer Cells

DEFF Research Database (Denmark)

Bach, Lars Arve; Sumpter, David J.T.; Alsner, Jan

2003-01-01

Evolutionary game models of cellular interactions have shown that heterogeneity in the cellular genotypic composition is maintained through evolution to stable coexistence of growth-promoting and non-promoting cell types. We generalise these mean-field models and relax the assumption of perfect...... mixing of cells by instead implementing an individual-based model that includes the stochastic and spatial effects likely to occur in tumours. The scope for coexistence of genotypic strategies changed with the inclusion of explicit space and stochasticity. The spatial models show some interesting...... deviations from their mean-field counterparts, for example the possibility of altruistic (paracrine) cell strategies to thrive. Such effects can however, be highly sensitive to model implementation and the more realistic models with semi-synchronous and stochastic updating do not show evolution of altruism...

Evolutionary impact assessment: accounting for evolutionary consequences of fishing in an ecosystem approach to fisheries management.

Science.gov (United States)

Laugen, Ane T; Engelhard, Georg H; Whitlock, Rebecca; Arlinghaus, Robert; Dankel, Dorothy J; Dunlop, Erin S; Eikeset, Anne M; Enberg, Katja; Jørgensen, Christian; Matsumura, Shuichi; Nusslé, Sébastien; Urbach, Davnah; Baulier, Loїc; Boukal, David S; Ernande, Bruno; Johnston, Fiona D; Mollet, Fabian; Pardoe, Heidi; Therkildsen, Nina O; Uusi-Heikkilä, Silva; Vainikka, Anssi; Heino, Mikko; Rijnsdorp, Adriaan D; Dieckmann, Ulf

2014-03-01

Managing fisheries resources to maintain healthy ecosystems is one of the main goals of the ecosystem approach to fisheries (EAF). While a number of international treaties call for the implementation of EAF, there are still gaps in the underlying methodology. One aspect that has received substantial scientific attention recently is fisheries-induced evolution (FIE). Increasing evidence indicates that intensive fishing has the potential to exert strong directional selection on life-history traits, behaviour, physiology, and morphology of exploited fish. Of particular concern is that reversing evolutionary responses to fishing can be much more difficult than reversing demographic or phenotypically plastic responses. Furthermore, like climate change, multiple agents cause FIE, with effects accumulating over time. Consequently, FIE may alter the utility derived from fish stocks, which in turn can modify the monetary value living aquatic resources provide to society. Quantifying and predicting the evolutionary effects of fishing is therefore important for both ecological and economic reasons. An important reason this is not happening is the lack of an appropriate assessment framework. We therefore describe the evolutionary impact assessment (EvoIA) as a structured approach for assessing the evolutionary consequences of fishing and evaluating the predicted evolutionary outcomes of alternative management options. EvoIA can contribute to EAF by clarifying how evolution may alter stock properties and ecological relations, support the precautionary approach to fisheries management by addressing a previously overlooked source of uncertainty and risk, and thus contribute to sustainable fisheries.

"The Snake Raised Its Head": Content Novelty Alters the Reading Performance of Students at Risk for Reading Disabilities and ADHD

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Beike, Suzanne M.; Zentall, Sydney S.

2012-01-01

The purpose of this study was to assess the effects of story novelty (active verbs, less familiar characters, vivid adjectives, and surprising story endings) on the reading comprehension of 48 seven- to 11-year-old boys without clinical diagnoses of learning disabilities. The optimal stimulation theory provided the basis of the study, predicting…

Morphological Variation in Anuran Limbs: Constraints and Novelties.

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Fabrezi, Marissa; Goldberg, Javier; Chuliver Pereyra, Mariana

2017-09-01

Anurans have three primary types of locomotion: walking, jumping, and swimming. Additionally, they may dig, climb, grasp, etc. All adult anurans have four limbs, with four fingers on the hands and five toes on the feet. We summarized and updated knowledge on the interspecific variation within anuran limbs, then discuss how developmental constraints (e.g., in size) and novelties may have influenced anuran diversification through the locomotion. We analyze morphological variation from limb bud stages up to the final limb form resulting from certain skeletal organization and growth. We find limited morphometric variations in the skeleton of different developmental modules (i.e., skull, trunk, urostyle, limbs) indicate that the anuran body shape is largely constrained. We identify specializations of the stylopodium, zeugopodium, and proximal carpals/tarsals that have evolved to facilitiate saltatorial locomotion. We show that the anuran prepollex and prehallux are not vestigial digits and that they have come to serve specialized function. Medial rotation of the manus in anurans appears to have evolved to help distribute the force of impact upon landing at the end of a jump. Additional skeletal elements in anuran limbs are intercalary elements and sesamoids. The intercalary elements appear within neobatrachians and are integrated with digital pads in lineages capable of locomotion on smooth vertical surfaces. They have allowed arboreal anurans to occupy a wide range of arboreal habitats. © 2017 Wiley Periodicals, Inc.

Freud: the first evolutionary psychologist?

Science.gov (United States)

LeCroy, D

2000-04-01

An evolutionary perspective on attachment theory and psychoanalytic theory brings these two fields together in interesting ways. Application of the evolutionary principle of parent-offspring conflict to attachment theory suggests that attachment styles represent context-sensitive, evolved (adaptive) behaviors. In addition, an emphasis on offspring counter-strategies to adult reproductive strategies leads to consideration of attachment styles as overt manifestations of psychodynamic mediating processes, including the defense mechanisms of repression and reaction formation.

APOL1 Nephropathy: A Population Genetics and Evolutionary Medicine Detective Story.

Science.gov (United States)

Kruzel-Davila, Etty; Wasser, Walter G; Skorecki, Karl

2017-11-01

Common DNA sequence variants rarely have a high-risk association with a common disease. When such associations do occur, evolutionary forces must be sought, such as in the association of apolipoprotein L1 (APOL1) gene risk variants with nondiabetic kidney diseases in populations of African ancestry. The variants originated in West Africa and provided pathogenic resistance in the heterozygous state that led to high allele frequencies owing to an adaptive evolutionary selective sweep. However, the homozygous state is disadvantageous and is associated with a markedly increased risk of a spectrum of kidney diseases encompassing hypertension-attributed kidney disease, focal segmental glomerulosclerosis, human immunodeficiency virus nephropathy, sickle cell nephropathy, and progressive lupus nephritis. This scientific success story emerged with the help of the tools developed over the past 2 decades in human genome sequencing and population genomic databases. In this introductory article to a timely issue dedicated to illuminating progress in this area, we describe this unique population genetics and evolutionary medicine detective story. We emphasize the paradox of the inheritance mode, the missing heritability, and unresolved associations, including cardiovascular risk and diabetic nephropathy. We also highlight how genetic epidemiology elucidates mechanisms and how the principles of evolution can be used to unravel conserved pathways affected by APOL1 that may lead to novel therapies. The APOL1 gene provides a compelling example of a common variant association with common forms of nondiabetic kidney disease occurring in a continental population isolate with subsequent global admixture. Scientific collaboration using multiple experimental model systems and approaches should further clarify pathomechanisms further, leading to novel therapies. Copyright © 2017 Elsevier Inc. All rights reserved.

Stability of auditory discrimination and novelty processing in physiological aging.

Science.gov (United States)

Raggi, Alberto; Tasca, Domenica; Rundo, Francesco; Ferri, Raffaele

2013-01-01

Complex higher-order cognitive functions and their possible changes with aging are mandatory objectives of cognitive neuroscience. Event-related potentials (ERPs) allow investigators to probe the earliest stages of information processing. N100, Mismatch negativity (MMN) and P3a are auditory ERP components that reflect automatic sensory discrimination. The aim of the present study was to determine if N100, MMN and P3a parameters are stable in healthy aged subjects, compared to those of normal young adults. Normal young adults and older participants were assessed using standardized cognitive functional instruments and their ERPs were obtained with an auditory stimulation at two different interstimulus intervals, during a passive paradigm. All individuals were within the normal range on cognitive tests. No significant differences were found for any ERP parameters obtained from the two age groups. This study shows that aging is characterized by a stability of the auditory discrimination and novelty processing. This is important for the arrangement of normative for the detection of subtle preclinical changes due to abnormal brain aging.

Gene/Environment Interaction in Atherosclerosis: An Example of Clinical Medicine as Seen from the Evolutionary Perspective

Directory of Open Access Journals (Sweden)

Gerhard Mertens

2010-01-01

The chronic multifactorial disease of atherosclerosis clearly illustrates the Darwinian paradigm. Recent research, combining the effects of genes and environment, has provided surprising clues to the pathogenesis of this major public health problem. This example makes a strong case for recognizing evolution biology as a basic science for medicine.

Automatic detection of breast lesions with MIBI-Tc99m scintimammography using a novelty filter

International Nuclear Information System (INIS)

Costa, M.; Moura, L.

1996-01-01

An automatic method for detecting breast lesion in scintimammography is described. It is reported that the proposed method not only detects lesions but also classifies them as benign or malignant. The detection method makes use of Kohonen's novelty filter and the classification method is obtained by the analysis of an identified lesion mean profile. The method was able to detect all lesions presented in the scintimammogram and to correctly classify 16 out of 17 malignant lesions and 15 out of 17 benign lesions. The sensitivity of the method was 94,12% and specificity was 88,24%

CDMetaPOP: An individual-based, eco-evolutionary model for spatially explicit simulation of landscape demogenetics

Science.gov (United States)

Landguth, Erin L; Bearlin, Andrew; Day, Casey; Dunham, Jason B.

2016-01-01

1. Combining landscape demographic and genetics models offers powerful methods for addressing questions for eco-evolutionary applications.2. Using two illustrative examples, we present Cost–Distance Meta-POPulation, a program to simulate changes in neutral and/or selection-driven genotypes through time as a function of individual-based movement, complex spatial population dynamics, and multiple and changing landscape drivers.3. Cost–Distance Meta-POPulation provides a novel tool for questions in landscape genetics by incorporating population viability analysis, while linking directly to conservation applications.

Evolutionary history of the recruitment of conserved developmental genes in association to the formation and diversification of a novel trait

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Shirai Leila T

2012-02-01

Full Text Available Abstract Background The origin and modification of novel traits are important aspects of biological diversification. Studies combining concepts and approaches of developmental genetics and evolutionary biology have uncovered many examples of the recruitment, or co-option, of genes conserved across lineages for the formation of novel, lineage-restricted traits. However, little is known about the evolutionary history of the recruitment of those genes, and of the relationship between them -for example, whether the co-option involves whole or parts of existing networks, or whether it occurs by redeployment of individual genes with de novo rewiring. We use a model novel trait, color pattern elements on butterfly wings called eyespots, to explore these questions. Eyespots have greatly diversified under natural and sexual selection, and their formation involves genetic circuitries shared across insects. Results We investigated the evolutionary history of the recruitment and co-recruitment of four conserved transcription regulators to the larval wing disc region where circular pattern elements develop. The co-localization of Antennapedia, Notch, Distal-less, and Spalt with presumptive (eyespot organizers was examined in 13 butterfly species, providing the largest comparative dataset available for the system. We found variation between families, between subfamilies, and between tribes. Phylogenetic reconstructions by parsimony and maximum likelihood methods revealed an unambiguous evolutionary history only for Antennapedia, with a resolved single origin of eyespot-associated expression, and many homoplastic events for Notch, Distal-less, and Spalt. The flexibility in the (co-recruitment of the targeted genes includes cases where different gene combinations are associated with morphologically similar eyespots, as well as cases where identical protein combinations are associated with very different phenotypes. Conclusions The evolutionary history of gene

A Hybrid Chaotic Quantum Evolutionary Algorithm

DEFF Research Database (Denmark)

Cai, Y.; Zhang, M.; Cai, H.

2010-01-01

A hybrid chaotic quantum evolutionary algorithm is proposed to reduce amount of computation, speed up convergence and restrain premature phenomena of quantum evolutionary algorithm. The proposed algorithm adopts the chaotic initialization method to generate initial population which will form a pe...... tests. The presented algorithm is applied to urban traffic signal timing optimization and the effect is satisfied....

Evolutionary psychology: new perspectives on cognition and motivation.

Science.gov (United States)

Cosmides, Leda; Tooby, John

2013-01-01

Evolutionary psychology is the second wave of the cognitive revolution. The first wave focused on computational processes that generate knowledge about the world: perception, attention, categorization, reasoning, learning, and memory. The second wave views the brain as composed of evolved computational systems, engineered by natural selection to use information to adaptively regulate physiology and behavior. This shift in focus--from knowledge acquisition to the adaptive regulation of behavior--provides new ways of thinking about every topic in psychology. It suggests a mind populated by a large number of adaptive specializations, each equipped with content-rich representations, concepts, inference systems, and regulatory variables, which are functionally organized to solve the complex problems of survival and reproduction encountered by the ancestral hunter-gatherers from whom we are descended. We present recent empirical examples that illustrate how this approach has been used to discover new features of attention, categorization, reasoning, learning, emotion, and motivation.

Evolutionary medicine: its scope, interest and potential.

Science.gov (United States)

Stearns, Stephen C

2012-11-07

This review is aimed at readers seeking an introductory overview, teaching courses and interested in visionary ideas. It first describes the range of topics covered by evolutionary medicine, which include human genetic variation, mismatches to modernity, reproductive medicine, degenerative disease, host-pathogen interactions and insights from comparisons with other species. It then discusses priorities for translational research, basic research and health management. Its conclusions are that evolutionary thinking should not displace other approaches to medical science, such as molecular medicine and cell and developmental biology, but that evolutionary insights can combine with and complement established approaches to reduce suffering and save lives. Because we are on the cusp of so much new research and innovative insights, it is hard to estimate how much impact evolutionary thinking will have on medicine, but it is already clear that its potential is enormous.

Temporal knowledge and autobiographical memory: an evolutionary perspective

OpenAIRE

Skowronski, John J.; Sedikides, Constantine

2007-01-01

Section I: Philosophical issues 1. Evolutionary pyschology in the round , Robin Dunbar & Louise Barrett 2. The power of culture , Henry Plotkin 3. Evolution and psychology in philosophical perspective , Matteo Mameli 4. Niche construction, human behavioural ecology and evolutionary psychology , Kevin N Laland 5. Group level evolutionary processes , David Sloan Wilson Section II: The comparative Approach 6. Homologizing the mind , Drew Rendall, Hugh Nottman & John ...

The ABCs of an evolutionary education science: The academic, behavioral, and cultural implications of an evolutionary approach to education theory and practice

Science.gov (United States)

Kauffman, Rick, Jr.

Calls for improving research-informed policy in education are everywhere. Yet, while there is an increasing trend towards science-based practice, there remains little agreement over which of the sciences to consult and how to organize a collective effort between them. What Education lacks is a general theoretical framework through which policies can be constructed, implemented, and assessed. This dissertation submits that evolutionary theory can provide a suitable framework for coordinating educational policies and practice, and can provide the entire field of education with a clearer sense of how to better manage the learning environment. This dissertation explores two broad paths that outline the conceptual foundations for an Evolutionary Education Science: "Teaching Evolution" and "Using Evolution to Teach." Chapter 1 introduces both of these themes. After describing why evolutionary science is best suited for organizing education research and practice, Chapter 1 proceeds to "teach" an overview of the "evolutionary toolkit"---the mechanisms and principles that underlie the modern evolutionary perspective. The chapter then employs the "toolkit" in examining education from an evolutionary perspective, outlining the evolutionary precepts that can guide theorizing and research in education, describing how educators can "use evolution to teach.". Chapters 2-4 expand on this second theme. Chapters 2 and 3 describe an education program for at-risk 9th and 10th grade students, the Regents Academy, designed entirely with evolutionary principles in mind. The program was rigorously assessed in a randomized control design and has demonstrated success at improving students' academic performance (Chapter 2) and social & behavioral development (Chapter 3). Chapter 4 examines current teaching strategies that underlie effective curriculum-instruction-assessment practices and proposes a framework for organizing successful, evidence-based strategies for neural

Plant traits and plant biogeography control the biotic resistance provided by generalist herbivores

NARCIS (Netherlands)

Grutters, B.M.C.; Roijendijk, Yvonne; Verberk, W.C.E.P.; Bakker, E.S.

2017-01-01

1.Globalization and climate change trigger species invasions and range shifts, which reshuffle communities at an exceptional rate and expose plant migrants to unfamiliar herbivores. Dominant hypotheses to predict plant success are based on evolutionary novelty: either herbivores are maladapted to

Evo-devo of novel traits : the genetic basis of butterfly colour patterns

NARCIS (Netherlands)

Saenko, Suzanne Viatcheslavovna

2010-01-01

The origin and diversification of novel morphological traits is a major research theme in evolutionary developmental biology, or evo-devo. Wing patterns of butterflies, in particular eyespots, are lineage-specific novelties crucial for visual communication. This thesis explores different aspects of

Evolutionary Game Theory: A Renaissance

Directory of Open Access Journals (Sweden)

Jonathan Newton

2018-05-01

Full Text Available Economic agents are not always rational or farsighted and can make decisions according to simple behavioral rules that vary according to situation and can be studied using the tools of evolutionary game theory. Furthermore, such behavioral rules are themselves subject to evolutionary forces. Paying particular attention to the work of young researchers, this essay surveys the progress made over the last decade towards understanding these phenomena, and discusses open research topics of importance to economics and the broader social sciences.

Evolutionary constrained optimization

CERN Document Server

Deb, Kalyanmoy

2015-01-01

This book makes available a self-contained collection of modern research addressing the general constrained optimization problems using evolutionary algorithms. Broadly the topics covered include constraint handling for single and multi-objective optimizations; penalty function based methodology; multi-objective based methodology; new constraint handling mechanism; hybrid methodology; scaling issues in constrained optimization; design of scalable test problems; parameter adaptation in constrained optimization; handling of integer, discrete and mix variables in addition to continuous variables; application of constraint handling techniques to real-world problems; and constrained optimization in dynamic environment. There is also a separate chapter on hybrid optimization, which is gaining lots of popularity nowadays due to its capability of bridging the gap between evolutionary and classical optimization. The material in the book is useful to researchers, novice, and experts alike. The book will also be useful...

The secondary loss of gyrencephaly as an example of evolutionary phenotypical reversal

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Iva eKelava

2013-06-01

Full Text Available Gyrencephaly (the folding of the surface of the neocortex is a mammalian-specific trait present in almost all mammalian orders. Despite the widespread appearance of the trait, little is known about the mechanism of its genesis or its adaptive significance. Still, most of the hypotheses proposed concentrated on the pattern of connectivity of mature neurons as main components of gyri formation. Recent work on embryonic neurogenesis in several species of mammals revealed different progenitor and stem cells and their neurogenic potential as having important roles in the process of gyrification. Studies in the field of comparative neurogenesis revealed that gyrencephaly is an evolutionarily labile trait, and that some species underwent a secondary loss of a convoluted brain surface and thus reverted to a more ancient form, a less folded brain surface (lissencephaly. This phenotypic reversion provides an excellent system for understanding the phenomenon of secondary loss. In this review, we will outline the theory behind secondary loss and, as specific examples, present species that have undergone this transition with respect to neocortical folding. We will also discuss different possible pathways for obtaining (or losing gyri. Finally, we will explore the potential adaptive consequence of gyrencephaly relative to lissencephaly and vice versa.

Evolutionary Computation and Its Applications in Neural and Fuzzy Systems

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Biaobiao Zhang

2011-01-01

Full Text Available Neural networks and fuzzy systems are two soft-computing paradigms for system modelling. Adapting a neural or fuzzy system requires to solve two optimization problems: structural optimization and parametric optimization. Structural optimization is a discrete optimization problem which is very hard to solve using conventional optimization techniques. Parametric optimization can be solved using conventional optimization techniques, but the solution may be easily trapped at a bad local optimum. Evolutionary computation is a general-purpose stochastic global optimization approach under the universally accepted neo-Darwinian paradigm, which is a combination of the classical Darwinian evolutionary theory, the selectionism of Weismann, and the genetics of Mendel. Evolutionary algorithms are a major approach to adaptation and optimization. In this paper, we first introduce evolutionary algorithms with emphasis on genetic algorithms and evolutionary strategies. Other evolutionary algorithms such as genetic programming, evolutionary programming, particle swarm optimization, immune algorithm, and ant colony optimization are also described. Some topics pertaining to evolutionary algorithms are also discussed, and a comparison between evolutionary algorithms and simulated annealing is made. Finally, the application of EAs to the learning of neural networks as well as to the structural and parametric adaptations of fuzzy systems is also detailed.

The integration of Darwinism and evolutionary morphology: Alexej Nikolajevich Sewertzoff (1866-1936) and the developmental basis of evolutionary change.

Science.gov (United States)

Levit, George S; Hossfeld, Uwe; Olsson, Lennart

2004-07-15

The growth of evolutionary morphology in the late 19th and early 20th centuries was inspired by the work of Carl Gegenbaur (1826-1903) and his protégé and friend Ernst Haeckel (1834-1919). However, neither of them succeeded in creating and applying a strictly Darwinian (selectionist) methodology. This task was left to the next generation of evolutionary morphologists. In this paper we present a relatively unknown researcher, Alexej Nikolajevich Sewertzoff (1866-1936) who made important contributions towards a synthesis of Darwinism and evolutionary morphology. Copyright 2004 Wiley-Liss, Inc.

Novelty, Stress, and Biological Roots in Human Market Behavior

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Alexey Sarapultsev

2014-02-01

Full Text Available Although studies examining the biological roots of human behavior have been conducted since the seminal work Kahneman and Tversky, crises and panics have not disappeared. The frequent occurrence of various types of crises has led some economists to the conviction that financial markets occasionally praise irrational judgments and that market crashes cannot be avoided a priori (Sornette 2009; Smith 2004. From a biological point of view, human behaviors are essentially the same during crises accompanied by stock market crashes and during bubble growth when share prices exceed historic highs. During those periods, most market participants see something new for themselves, and this inevitably induces a stress response in them with accompanying changes in their endocrine profiles and motivations. The result is quantitative and qualitative changes in behavior (Zhukov 2007. An underestimation of the role of novelty as a stressor is the primary shortcoming of current approaches for market research. When developing a mathematical market model, it is necessary to account for the biologically determined diphasisms of human behavior in everyday low-stress conditions and in response to stressors. This is the only type of approach that will enable forecasts of market dynamics and investor behaviors under normal conditions as well as during bubbles and panics.

Evolutionary dynamics with fluctuating population sizes and strong mutualism

Science.gov (United States)

Chotibut, Thiparat; Nelson, David R.

2015-08-01

Game theory ideas provide a useful framework for studying evolutionary dynamics in a well-mixed environment. This approach, however, typically enforces a strictly fixed overall population size, deemphasizing natural growth processes. We study a competitive Lotka-Volterra model, with number fluctuations, that accounts for natural population growth and encompasses interaction scenarios typical of evolutionary games. We show that, in an appropriate limit, the model describes standard evolutionary games with both genetic drift and overall population size fluctuations. However, there are also regimes where a varying population size can strongly influence the evolutionary dynamics. We focus on the strong mutualism scenario and demonstrate that standard evolutionary game theory fails to describe our simulation results. We then analytically and numerically determine fixation probabilities as well as mean fixation times using matched asymptotic expansions, taking into account the population size degree of freedom. These results elucidate the interplay between population dynamics and evolutionary dynamics in well-mixed systems.

Evolutionary dynamics with fluctuating population sizes and strong mutualism.

Science.gov (United States)

Chotibut, Thiparat; Nelson, David R

2015-08-01

Game theory ideas provide a useful framework for studying evolutionary dynamics in a well-mixed environment. This approach, however, typically enforces a strictly fixed overall population size, deemphasizing natural growth processes. We study a competitive Lotka-Volterra model, with number fluctuations, that accounts for natural population growth and encompasses interaction scenarios typical of evolutionary games. We show that, in an appropriate limit, the model describes standard evolutionary games with both genetic drift and overall population size fluctuations. However, there are also regimes where a varying population size can strongly influence the evolutionary dynamics. We focus on the strong mutualism scenario and demonstrate that standard evolutionary game theory fails to describe our simulation results. We then analytically and numerically determine fixation probabilities as well as mean fixation times using matched asymptotic expansions, taking into account the population size degree of freedom. These results elucidate the interplay between population dynamics and evolutionary dynamics in well-mixed systems.

Islamic medicine and evolutionary medicine: a comparative analysis.

Science.gov (United States)

Saniotis, Arthur

2012-01-01

The advent of evolutionary medicine in the last two decades has provided new insights into the causes of human disease and possible preventative strategies. One of the strengths of evolutionary medicine is that it follows a multi-disciplinary approach. Such an approach is vital to future biomedicine as it enables for the infiltration of new ideas. Although evolutionary medicine uses Darwinian evolution as a heuristic for understanding human beings' susceptibility to disease, this is not necessarily in conflict with Islamic medicine. It should be noted that current evolutionary theory was first expounded by various Muslim scientists such as al-Jāḥiẓ, al-Ṭūsī, Ibn Khaldūn and Ibn Maskawayh centuries before Darwin and Wallace. In this way, evolution should not be viewed as being totally antithetical to Islam. This article provides a comparative overview of Islamic medicine and Evolutionary medicine as well as drawing points of comparison between the two approaches which enables their possible future integration.

[Evolutionary perspective in precocious puberty].

Science.gov (United States)

Hochberg, Ze'ev

2014-10-01

Pubertal development is subject to substantial heritability, but much variation remains to be explained, including fast changes over the last 150 years, that cannot be explained by changes of gene frequency in the population. This article discusses the influence of environmental factors to adjust maturational tempo in the service of fitness goals. Utilizing evolutionary development thinking (evo-devo), the author examines adolescence as an evolutionary life-history stage in its developmental context. The transition from the preceding stage of juvenility entails adaptive plasticity in response to energy resources, social needs of adolescence and maturation toward youth and adulthood. Using Belsky's evolutionary theory of socialization, I show that familial psychosocial environment during the infancy-childhood and childhood-juvenility transitions foster a fast life-history and reproductive strategy rather than early maturation being just a risk factor for aggression and delinquency. The implications of the evo-devo framework for theory building, illuminates new directions in the understanding of precocious puberty other than a diagnosis of a disease.

Evolutionary engineering for industrial microbiology.

Science.gov (United States)

Vanee, Niti; Fisher, Adam B; Fong, Stephen S

2012-01-01

Superficially, evolutionary engineering is a paradoxical field that balances competing interests. In natural settings, evolution iteratively selects and enriches subpopulations that are best adapted to a particular ecological niche using random processes such as genetic mutation. In engineering desired approaches utilize rational prospective design to address targeted problems. When considering details of evolutionary and engineering processes, more commonality can be found. Engineering relies on detailed knowledge of the problem parameters and design properties in order to predict design outcomes that would be an optimized solution. When detailed knowledge of a system is lacking, engineers often employ algorithmic search strategies to identify empirical solutions. Evolution epitomizes this iterative optimization by continuously diversifying design options from a parental design, and then selecting the progeny designs that represent satisfactory solutions. In this chapter, the technique of applying the natural principles of evolution to engineer microbes for industrial applications is discussed to highlight the challenges and principles of evolutionary engineering.

Handbook of differential equations evolutionary equations

CERN Document Server

Dafermos, CM

2008-01-01

The material collected in this volume discusses the present as well as expected future directions of development of the field with particular emphasis on applications. The seven survey articles present different topics in Evolutionary PDE's, written by leading experts.- Review of new results in the area- Continuation of previous volumes in the handbook series covering Evolutionary PDEs- Written by leading experts

The non-random clustering of non-synonymous substitutions and its relationship to evolutionary rate

Directory of Open Access Journals (Sweden)

Stone Eric A

2011-08-01

Full Text Available Abstract Background Protein sequences are subject to a mosaic of constraint. Changes to functional domains and buried residues, for example, are more apt to disrupt protein structure and function than are changes to residues participating in loops or exposed to solvent. Regions of constraint on the tertiary structure of a protein often result in loose segmentation of its primary structure into stretches of slowly- and rapidly-evolving amino acids. This clustering can be exploited, and existing methods have done so by relying on local sequence conservation as a signature of selection to help identify functionally important regions within proteins. We invert this paradigm by leveraging the regional nature of protein structure and function to both illuminate and make use of genome-wide patterns of local sequence conservation. Results Our hypothesis is that the regional nature of structural and functional constraints will assert a positive autocorrelation on the evolutionary rates of neighboring sites, which, in a pairwise comparison of orthologous proteins, will manifest itself as the clustering of non-synonymous changes across the amino acid sequence. We introduce a dispersion ratio statistic to test this and related hypotheses. Using genome-wide interspecific comparisons of orthologous protein pairs, we reveal a strong log-linear relationship between the degree of clustering and the intensity of constraint. We further demonstrate how this relationship varies with the evolutionary distance between the species being compared. We provide some evidence that proteins with a history of positive selection deviate from genome-wide trends. Conclusions We find a significant association between the evolutionary rate of a protein and the degree to which non-synonymous changes cluster along its primary sequence. We show that clustering is a non-redundant predictor of evolutionary rate, and we speculate that conflicting signals of clustering and constraint may

Evolutionary algorithms for mobile ad hoc networks

CERN Document Server

Dorronsoro, Bernabé; Danoy, Grégoire; Pigné, Yoann; Bouvry, Pascal

2014-01-01

Describes how evolutionary algorithms (EAs) can be used to identify, model, and minimize day-to-day problems that arise for researchers in optimization and mobile networking. Mobile ad hoc networks (MANETs), vehicular networks (VANETs), sensor networks (SNs), and hybrid networks—each of these require a designer’s keen sense and knowledge of evolutionary algorithms in order to help with the common issues that plague professionals involved in optimization and mobile networking. This book introduces readers to both mobile ad hoc networks and evolutionary algorithms, presenting basic concepts as well as detailed descriptions of each. It demonstrates how metaheuristics and evolutionary algorithms (EAs) can be used to help provide low-cost operations in the optimization process—allowing designers to put some “intelligence” or sophistication into the design. It also offers efficient and accurate information on dissemination algorithms topology management, and mobility models to address challenges in the ...

Testing inferences in developmental evolution: the forensic evidence principle.

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Larsson, Hans C E; Wagner, Günter P

2012-09-01

Developmental evolution (DE) examines the influence of developmental mechanisms on biological evolution. Here we consider the question: "what is the evidence that allows us to decide whether a certain developmental scenario for an evolutionary change is in fact "correct" or at least falsifiable?" We argue that the comparative method linked with what we call the "forensic evidence principle" (FEP) is sufficient to conduct rigorous tests of DE scenarios. The FEP states that different genetically mediated developmental causes of an evolutionary transformation will leave different signatures in the development of the derived character. Although similar inference rules have been used in practically every empirical science, we expand this approach here in two ways: (1) we justify the validity of this principle with reference to a well-known result from mathematical physics, known as the symmetry principle, and (2) propose a specific form of the FEP for DE: given two or more developmental explanations for a certain evolutionary event, say an evolutionary novelty, then the evidence discriminating between these hypotheses will be found in the most proximal internal drivers of the derived character. Hence, a detailed description of the ancestral and derived states, and their most proximal developmental drivers are necessary to discriminate between various evolutionary developmental hypotheses. We discuss how this stepwise order of testing is necessary, establishes a formal test, and how skipping this order of examination may violate a more accurate examination of DE. We illustrate the approach with an example from avian digit evolution. © 2012 Wiley Periodicals, Inc.

Human genomic disease variants: a neutral evolutionary explanation.

Science.gov (United States)

Dudley, Joel T; Kim, Yuseob; Liu, Li; Markov, Glenn J; Gerold, Kristyn; Chen, Rong; Butte, Atul J; Kumar, Sudhir

2012-08-01

Many perspectives on the role of evolution in human health include nonempirical assumptions concerning the adaptive evolutionary origins of human diseases. Evolutionary analyses of the increasing wealth of clinical and population genomic data have begun to challenge these presumptions. In order to systematically evaluate such claims, the time has come to build a common framework for an empirical and intellectual unification of evolution and modern medicine. We review the emerging evidence and provide a supporting conceptual framework that establishes the classical neutral theory of molecular evolution (NTME) as the basis for evaluating disease- associated genomic variations in health and medicine. For over a decade, the NTME has already explained the origins and distribution of variants implicated in diseases and has illuminated the power of evolutionary thinking in genomic medicine. We suggest that a majority of disease variants in modern populations will have neutral evolutionary origins (previously neutral), with a relatively smaller fraction exhibiting adaptive evolutionary origins (previously adaptive). This pattern is expected to hold true for common as well as rare disease variants. Ultimately, a neutral evolutionary perspective will provide medicine with an informative and actionable framework that enables objective clinical assessment beyond convenient tendencies to invoke past adaptive events in human history as a root cause of human disease.

Comparing Evolutionary Strategies on a Biobjective Cultural Algorithm

Directory of Open Access Journals (Sweden)

Carolina Lagos

2014-01-01

Full Text Available Evolutionary algorithms have been widely used to solve large and complex optimisation problems. Cultural algorithms (CAs are evolutionary algorithms that have been used to solve both single and, to a less extent, multiobjective optimisation problems. In order to solve these optimisation problems, CAs make use of different strategies such as normative knowledge, historical knowledge, circumstantial knowledge, and among others. In this paper we present a comparison among CAs that make use of different evolutionary strategies; the first one implements a historical knowledge, the second one considers a circumstantial knowledge, and the third one implements a normative knowledge. These CAs are applied on a biobjective uncapacitated facility location problem (BOUFLP, the biobjective version of the well-known uncapacitated facility location problem. To the best of our knowledge, only few articles have applied evolutionary multiobjective algorithms on the BOUFLP and none of those has focused on the impact of the evolutionary strategy on the algorithm performance. Our biobjective cultural algorithm, called BOCA, obtains important improvements when compared to other well-known evolutionary biobjective optimisation algorithms such as PAES and NSGA-II. The conflicting objective functions considered in this study are cost minimisation and coverage maximisation. Solutions obtained by each algorithm are compared using a hypervolume S metric.

Optimum topology for radial networks by using evolutionary computer programming; Topologia optima de redes radiais utilizando programacao evolucionaria

Energy Technology Data Exchange (ETDEWEB)

Pinto, Joao Luis [Instituto de Engenhariade Sistemas e Computadores (INESC), Porto (Portugal). E-mail: jpinto@duque.inescn.pt; Proenca, Luis Miguel [Instituto Superior de Linguas e Administracao (ISLA), Gaia (Portugal). E-mail: lproenca@inescn.pt

1999-07-01

This paper describes the using of Evolutionary Programming techniques for determination of the radial electric network topology, considering investment costs and losses. The work aims to demonstrate the particular easiness of coding and implementation and the parallelism implicit to the method as well, giving outstanding performance levels. As test example, a 43 bars and 75 alternative lines network has been used by describing an implementation of the algorithm in an Object Oriented platform.

Automated novelty detection in the WISE survey with one-class support vector machines

Science.gov (United States)

Solarz, A.; Bilicki, M.; Gromadzki, M.; Pollo, A.; Durkalec, A.; Wypych, M.

2017-10-01

Wide-angle photometric surveys of previously uncharted sky areas or wavelength regimes will always bring in unexpected sources - novelties or even anomalies - whose existence and properties cannot be easily predicted from earlier observations. Such objects can be efficiently located with novelty detection algorithms. Here we present an application of such a method, called one-class support vector machines (OCSVM), to search for anomalous patterns among sources preselected from the mid-infrared AllWISE catalogue covering the whole sky. To create a model of expected data we train the algorithm on a set of objects with spectroscopic identifications from the SDSS DR13 database, present also in AllWISE. The OCSVM method detects as anomalous those sources whose patterns - WISE photometric measurements in this case - are inconsistent with the model. Among the detected anomalies we find artefacts, such as objects with spurious photometry due to blending, but more importantly also real sources of genuine astrophysical interest. Among the latter, OCSVM has identified a sample of heavily reddened AGN/quasar candidates distributed uniformly over the sky and in a large part absent from other WISE-based AGN catalogues. It also allowed us to find a specific group of sources of mixed types, mostly stars and compact galaxies. By combining the semi-supervised OCSVM algorithm with standard classification methods it will be possible to improve the latter by accounting for sources which are not present in the training sample, but are otherwise well-represented in the target set. Anomaly detection adds flexibility to automated source separation procedures and helps verify the reliability and representativeness of the training samples. It should be thus considered as an essential step in supervised classification schemes to ensure completeness and purity of produced catalogues. The catalogues of outlier data are only available at the CDS via anonymous ftp to http

An Evolutionary Psychology Approach to Consumer Choice

Directory of Open Access Journals (Sweden)

ZURINA BT MOHAIDIN

2013-07-01

Full Text Available Human behaviour can be explained not only through experience and environments but also by incorporating evolutionary explanation. Consumer behaviour could not be understood accurately without infusing Darwinian evolutionary theory which has contributed in the knowledge of human nature. Evolutionary psychology revolves around the human’s evolved mental and the impact on human’s traits and behaviour where the influence of the environment to our genes would determine our individual behaviour and traits, resulting in variation among us. Foraging which is a part of behavioural ecology involves many sequences or repetitions of animals’ activities and decision making which is useful to relate these patterns of activities to the decisions made in human consumption. The aim of this research is to investigate the similarities of human consumption and ecological behaviour by employing interpretative and comparative approach. It is hoped that by applying the evolutionary theory in explaining consumer choice, this study is able to contribute to the development of behavioural ecology in human consumption. The analysis of the data is done aggregately for 200 consumers and individually for 20 consumers, who have purchased four product categories over a year. This study concludes that the theories of evolutionary psychology can fit to the consumers’ buying behaviour implicating its usefulness in explaining the consumers’ choice.

Effects of Cannabinoid Exposure during Adolescence on the Conditioned Rewarding Effects of WIN 55212-2 and Cocaine in Mice: Influence of the Novelty-Seeking Trait

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M. Rodríguez-Arias

2016-01-01

Full Text Available Adolescent exposure to cannabinoids enhances the behavioural effects of cocaine, and high novelty-seeking trait predicts greater sensitivity to the conditioned place preference (CPP induced by this drug. Our aim was to evaluate the influence of novelty-seeking on the effects of adolescent cannabinoid exposure. Adolescent male mice were classified as high or low novelty seekers (HNS and LNS in the hole-board test. First, we evaluated the CPP induced by the cannabinoid agonist WIN 55212-2 (0.05 and 0.075 mg/kg, i.p. in HNS and LNS mice. Then, HNS and LNS mice were pretreated i.p. with vehicle, WIN 55212-2 (0.1 mg/kg, or cannabinoid antagonist rimonabant (1 mg/kg and were subsequently conditioned with WIN 55212-2 (0.05 mg/kg, i.p. or cocaine (1 or 6 mg/kg, i.p.. Only HNS mice conditioned with the 0.075 mg/kg dose acquired CPP with WIN 55212-2. Adolescent exposure to this cannabinoid agonist increased the rewarding effects of 1 mg/kg of cocaine in both HNS and LNS mice, and in HNS mice it also increased the reinstating effect of a low dose of cocaine. Our results endorse a role for individual differences such as a higher propensity for sensation-seeking in the development of addiction.

The four cornerstones of Evolutionary Toxicology.

Science.gov (United States)

Bickham, John W

2011-05-01

Evolutionary Toxicology is the study of the effects of chemical pollutants on the genetics of natural populations. Research in Evolutionary Toxicology uses experimental designs familiar to the ecotoxicologist with matched reference and contaminated sites and the selection of sentinel species. It uses the methods of molecular genetics and population genetics, and is based on the theories and concepts of evolutionary biology and conservation genetics. Although it is a relatively young field, interest is rapidly growing among ecotoxicologists and more and more field studies and even controlled laboratory experiments are appearing in the literature. A number of population genetic impacts have been observed in organisms exposed to pollutants which I refer to here as the four cornerstones of Evolutionary Toxicology. These include (1) genome-wide changes in genetic diversity, (2) changes in allelic or genotypic frequencies caused by contaminant-induced selection acting at survivorship loci, (3) changes in dispersal patterns or gene flow which alter the genetic relationships among populations, and (4) changes in allelic or genotypic frequencies caused by increased mutation rates. It is concluded that population genetic impacts of pollution exposure are emergent effects that are not necessarily predictable from the mode of toxicity of the pollutant. Thus, to attribute an effect to a particular contaminant requires a careful experimental design which includes selection of appropriate reference sites, detailed chemistry analyses of environmental samples and tissues, and the use of appropriate biomarkers to establish exposure and effect. This paper describes the field of Evolutionary Toxicology and discusses relevant field studies and their findings. © Springer Science+Business Media, LLC 2011

Applied evolutionary economics and economic geography

OpenAIRE

Peter Sunley

2008-01-01

Applied Evolutionary Economics and Economic Geography aims to further advance empirical methodologies in evolutionary economics, with a special emphasis on geography and firm location. It does so by bringing together a select group of leading scholars including economists, geographers and sociologists, all of whom share an interest in explaining the uneven distribution of economic activities in space and the historical processes that have produced these patterns.

Neural and environmental factors impacting maternal behavior differences in high- versus low-novelty-seeking rats.

Science.gov (United States)

Clinton, Sarah M; Bedrosian, Tracy A; Abraham, Antony D; Watson, Stanley J; Akil, Huda

2010-04-01

Selective breeding of rats exhibiting differences in novelty-induced locomotion revealed that this trait predicts several differences in emotional behavior. Bred High Responders (bHRs) show exaggerated novelty-induced locomotion, aggression, and psychostimulant self-administration, compared to bred Low Responders (bLRs), which are inhibited and prone to anxiety- and depression-like behavior. Our breeding studies highlight the heritability of the bHR/bLR phenotypes, although environmental factors like maternal care also shape some aspects of these traits. We previously reported that HR vs. LR mothers act differently, but it was unclear whether their behaviors were genetically driven or influenced by their pups. The present study (a) used cross-fostering to evaluate whether the bHR/bLR maternal styles are inherent to mothers and/or are modulated by pups; and (b) assessed oxytocin and oxytocin receptor mRNA expression to examine possible underpinnings of bHR/bLR maternal differences. While bHR dams exhibited less maternal behavior than bLRs during the dark/active phase, they were very attentive to pups during the light phase, spending greater time passive nursing and in contact with pups compared to bLRs. Cross-fostering only subtly changed bHR and bLR dams' behavior, suggesting that their distinct maternal styles are largely inherent to the mothers. We also found elevated oxytocin mRNA levels in the supraoptic nucleus of the hypothalamus in bHR versus bLR dams, which may play some role in driving their behavior differences. Overall these studies shed light on the interplay between the genetics of mothers and infants in driving differences in maternal style. Copyright 2010 Elsevier Inc. All rights reserved.

Stress during adolescence increases novelty seeking and risk taking behavior in male and female rats

Directory of Open Access Journals (Sweden)

Maria eToledo

2011-04-01

Full Text Available Adolescence is a period of major physical, hormonal and psychological change. It is also characterized by a significant increase in the incidence of psychopathologies and this increase is gender-specific. Likewise, stress during adolescence is associated with the development of psychiatric disorders later in life. Previously, using a rat model of psychogenic stress (exposure to predator odor followed by placement on an elevated platform during the pre-pubertal period (postnatal days 28-30, we reported sex-specific effects on auditory and contextual fear conditioning. Here, we study the short-term impact of psychogenic stress before and during puberty (postnatal days 28-42 on behavior (novelty seeking, risk taking, anxiety and depression and hypothalamus-pituitary-adrenocortical (HPA axis activation during late adolescence (postnatal days 45-51. Peri-pubertal stress decreased anxiety-like behavior and increased risk taking and novelty seeking behaviors during late adolescence (measured with the elevated plus maze, open field and exposure to novel object tests and intake of chocopop pellets before or immediate after stress. Finally neither depressive-like behavior (measured at the forced swim test nor HPA response to stress (blood corticosterone and glucose were affected by peri-pubertal stress. Nevertheless, when controlling for the basal anxiety of the mothers, animals exposed to peri-pubertal stress showed a significant decrease in corticosterone levels immediate after an acute stressor. The results from this study suggest that exposure to mild stressors during the peri-pubertal period induces a broad spectrum of behavioral changes in late adolescence, which may exacerbate the independence-building behaviors naturally happening during this transitional period (increase in curiosity, sensation-seeking and risk taking behaviors.

Tangled trios? Characterizing a hybrid zone in Castilleja (Orobanchaceae)

Science.gov (United States)

Erika l. Hersch-Green; Richard. Cronn

2009-01-01

Hybridization and polyploidization are exceedingly important processes because both influence the ecological envelope and evolutionary trajectory of land plants. These processes are frequently invoked for Castilleja (Indian paintbrushes) as contributors to morphological and genetic novelty and as complicating factors in species delimitations. Here...

On economic applications of evolutionary game theory

OpenAIRE

Daniel Friedman

1998-01-01

Evolutionary games have considerable unrealized potential for modeling substantive economic issues. They promise richer predictions than orthodox game models but often require more extensive specifications. This paper exposits the specification of evolutionary game models and classifies the possible asymptotic behavior for one and two dimensional models.

On the Evolutionary Stability of Bargaining Inefficiency

DEFF Research Database (Denmark)

Poulsen, Anders

This paper investigates whether 'tough' bargaining behavior, which gives rise to inefficiency, can be evolutionary stable. We show that in a two-stage Nash Demand Game tough behavior survives. Indeed, almost all the surplus may be wasted. We also study the Ultimatum Game. Here evolutionary select...

Evolutionary/advanced light water reactor data report

Energy Technology Data Exchange (ETDEWEB)

NONE

1996-02-09

The US DOE Office of Fissile Material Disposition is examining options for placing fissile materials that were produced for fabrication of weapons, and now are deemed to be surplus, into a condition that is substantially irreversible and makes its use in weapons inherently more difficult. The principal fissile materials subject to this disposition activity are plutonium and uranium containing substantial fractions of plutonium-239 uranium-235. The data in this report, prepared as technical input to the fissile material disposition Programmatic Environmental Impact Statement (PEIS) deal only with the disposition of plutonium that contains well over 80% plutonium-239. In fact, the data were developed on the basis of weapon-grade plutonium which contains, typically, 93.6% plutonium-239 and 5.9% plutonium-240 as the principal isotopes. One of the options for disposition of weapon-grade plutonium being considered is the power reactor alternative. Plutonium would be fabricated into mixed oxide (MOX) fuel and fissioned (``burned``) in a reactor to produce electric power. The MOX fuel will contain dioxides of uranium and plutonium with less than 7% weapon-grade plutonium and uranium that has about 0.2% uranium-235. The disposition mission could, for example, be carried out in existing power reactors, of which there are over 100 in the United States. Alternatively, new LWRs could be constructed especially for disposition of plutonium. These would be of the latest US design(s) incorporating numerous design simplifications and safety enhancements. These ``evolutionary`` or ``advanced`` designs would offer not only technological advances, but also flexibility in siting and the option of either government or private (e.g., utility) ownership. The new reactor designs can accommodate somewhat higher plutonium throughputs. This data report deals solely with the ``evolutionary`` LWR alternative.

Evolutionary/advanced light water reactor data report

International Nuclear Information System (INIS)

1996-01-01

The US DOE Office of Fissile Material Disposition is examining options for placing fissile materials that were produced for fabrication of weapons, and now are deemed to be surplus, into a condition that is substantially irreversible and makes its use in weapons inherently more difficult. The principal fissile materials subject to this disposition activity are plutonium and uranium containing substantial fractions of plutonium-239 uranium-235. The data in this report, prepared as technical input to the fissile material disposition Programmatic Environmental Impact Statement (PEIS) deal only with the disposition of plutonium that contains well over 80% plutonium-239. In fact, the data were developed on the basis of weapon-grade plutonium which contains, typically, 93.6% plutonium-239 and 5.9% plutonium-240 as the principal isotopes. One of the options for disposition of weapon-grade plutonium being considered is the power reactor alternative. Plutonium would be fabricated into mixed oxide (MOX) fuel and fissioned (''burned'') in a reactor to produce electric power. The MOX fuel will contain dioxides of uranium and plutonium with less than 7% weapon-grade plutonium and uranium that has about 0.2% uranium-235. The disposition mission could, for example, be carried out in existing power reactors, of which there are over 100 in the United States. Alternatively, new LWRs could be constructed especially for disposition of plutonium. These would be of the latest US design(s) incorporating numerous design simplifications and safety enhancements. These ''evolutionary'' or ''advanced'' designs would offer not only technological advances, but also flexibility in siting and the option of either government or private (e.g., utility) ownership. The new reactor designs can accommodate somewhat higher plutonium throughputs. This data report deals solely with the ''evolutionary'' LWR alternative

Evolutionary Robotics: What, Why, and Where to

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Stephane eDoncieux

2015-03-01

Full Text Available Evolutionary robotics applies the selection, variation, and heredity principles of natural evolution to the design of robots with embodied intelligence. It can be considered as a subfield of robotics that aims to create more robust and adaptive robots. A pivotal feature of the evolutionary approach is that it considers the whole robot at once, and enables the exploitation of robot features in a holistic manner. Evolutionary robotics can also be seen as an innovative approach to the study of evolution based on a new kind of experimentalism. The use of robots as a substrate can help address questions that are difficult, if not impossible, to investigate through computer simulations or biological studies. In this paper we consider the main achievements of evolutionary robotics, focusing particularly on its contributions to both engineering and biology. We briefly elaborate on methodological issues, review some of the most interesting findings, and discuss important open issues and promising avenues for future work.

Ecological and evolutionary influences on body size and shape in the Galápagos marine iguana (Amblyrhynchus cristatus).

Science.gov (United States)

Chiari, Ylenia; Glaberman, Scott; Tarroso, Pedro; Caccone, Adalgisa; Claude, Julien

2016-07-01

Oceanic islands are often inhabited by endemic species that have undergone substantial morphological evolutionary change due to processes of multiple colonizations from various source populations, dispersal, and local adaptation. Galápagos marine iguanas are an example of an island endemic exhibiting high morphological diversity, including substantial body size variation among populations and sexes, but the causes and magnitude of this variation are not well understood. We obtained morphological measurements from marine iguanas throughout their distribution range. These data were combined with genetic and local environmental data from each population to investigate the effects of evolutionary history and environmental conditions on body size and shape variation and sexual dimorphism. Our results indicate that body size and shape are highly variable among populations. Sea surface temperature and island perimeter, but not evolutionary history as depicted by phylogeographic patterns in this species, explain variation in body size among populations. Conversely, evolutionary history, but not environmental parameters or island size, was found to influence variation in body shape among populations. Finally, in all populations except one, we found strong sexual dimorphism in body size and shape in which males are larger, with higher heads than females, while females have longer heads than males. Differences among populations suggest that plasticity and/or genetic adaptation may shape body size and shape variation in marine iguanas. This study will help target future investigations to address the contribution of plasticity versus genetic adaptation on size and shape variation in marine iguanas.

Where is, in 2017, the evo in evo-devo (evolutionary developmental biology)?

Science.gov (United States)

Diogo, Rui

2018-01-01

After the inaugural Pan-American-Evo-Devo meeting (2015, Berkeley), I showed how major concerns about evo-devo (Evolutionary Developmental Biology) research were demonstrated by a simple, non-biased quantitative analysis of the titles/abstracts of that meeting's talks. Here, I apply the same methodology to the titles/abstracts of the recent Pan-American-Evo-Devo meeting (2017, Calgary). The aim is to evaluate if the concerns raised by me in that paper and by other authors have been addressed and/or if there are other types of differences between the two meetings that may reflect trends within the field of evo-devo. This analysis shows that the proportion of presentations referring to "morphology", "organism", "selection", "adaptive", "phylogeny", and their derivatives was higher in the 2017 meeting, which therefore had a more "organismal" feel. However, there was a decrease in the use of "evolution"/its derivatives and of macroevolutionary terms related to the tempo and mode of evolution in the 2017 meeting. Moreover, the disproportionately high use of genetic/genomic terms clearly shows that evo-devo continues to be mainly focused on devo, and particularly on "Geno", that is, on molecular/genetic studies. Furthermore, the vast majority of animal evo-devo studies are focused only on hard tissues, which are just a small fraction of the whole organism-for example, only 15% of the tissue mass of the human body. The lack of an integrative approach is also evidenced by the lack of studies addressing conceptual/long-standing broader questions, including the links between ecology and particularly behavior and developmental/evolutionary variability and between evo-devo and evolutionary medicine. © 2018 Wiley Periodicals, Inc.

Evolutionary ethics from Darwin to Moore.

Science.gov (United States)

Allhoff, Fritz

2003-01-01

Evolutionary ethics has a long history, dating all the way back to Charles Darwin. Almost immediately after the publication of the Origin, an immense interest arose in the moral implications of Darwinism and whether the truth of Darwinism would undermine traditional ethics. Though the biological thesis was certainly exciting, nobody suspected that the impact of the Origin would be confined to the scientific arena. As one historian wrote, 'whether or not ancient populations of armadillos were transformed into the species that currently inhabit the new world was certainly a topic about which zoologists could disagree. But it was in discussing the broader implications of the theory...that tempers flared and statements were made which could transform what otherwise would have been a quiet scholarly meeting into a social scandal' (Farber 1994, 22). Some resistance to the biological thesis of Darwinism sprung from the thought that it was incompatible with traditional morality and, since one of them had to go, many thought that Darwinism should be rejected. However, some people did realize that a secular ethics was possible so, even if Darwinism did undermine traditional religious beliefs, it need not have any effects on moral thought. Before I begin my discussion of evolutionary ethics from Darwin to Moore, I would like to make some more general remarks about its development. There are three key events during this history of evolutionary ethics. First, Charles Darwin published On the Origin of the Species (Darwin 1859). Since one did not have a fully developed theory of evolution until 1859, there exists little work on evolutionary ethics until then. Shortly thereafter, Herbert Spencer (1898) penned the first systematic theory of evolutionary ethics, which was promptly attacked by T.H. Huxley (Huxley 1894). Second, at about the turn of the century, moral philosophers entered the fray and attempted to demonstrate logical errors in Spencer's work; such errors were alluded

[Charles Darwin and the problem of evolutionary progress].

Science.gov (United States)

Iordanskiĭ, N N

2010-01-01

According to Ch. Darwin's evolutionary theory, evolutionary progress (interpreted as morpho-physiological progress or arogenesis in recent terminology) is one of logical results of natural selection. At the same time, natural selection does not hold any factors especially promoting evolutionary progress. Darwin emphasized that the pattern of evolutionary changes depends on organism nature more than on the pattern of environment changes. Arogenesis specificity is determined by organization of rigorous biological systems - integral organisms. Onward progressive development is determined by fundamental features of living organisms: metabolism and homeostasis. The concept of social Darwinism differs fundamentally from Darwin's ideas about the most important role of social instincts in progress of mankind. Competition and selection play secondary role in socio-cultural progress of human society.

Natural pedagogy as evolutionary adaptation.

Science.gov (United States)

Csibra, Gergely; Gergely, György

2011-04-12

We propose that the cognitive mechanisms that enable the transmission of cultural knowledge by communication between individuals constitute a system of 'natural pedagogy' in humans, and represent an evolutionary adaptation along the hominin lineage. We discuss three kinds of arguments that support this hypothesis. First, natural pedagogy is likely to be human-specific: while social learning and communication are both widespread in non-human animals, we know of no example of social learning by communication in any other species apart from humans. Second, natural pedagogy is universal: despite the huge variability in child-rearing practices, all human cultures rely on communication to transmit to novices a variety of different types of cultural knowledge, including information about artefact kinds, conventional behaviours, arbitrary referential symbols, cognitively opaque skills and know-how embedded in means-end actions. Third, the data available on early hominin technological culture are more compatible with the assumption that natural pedagogy was an independently selected adaptive cognitive system than considering it as a by-product of some other human-specific adaptation, such as language. By providing a qualitatively new type of social learning mechanism, natural pedagogy is not only the product but also one of the sources of the rich cultural heritage of our species.

Natural pedagogy as evolutionary adaptation

Science.gov (United States)

Csibra, Gergely; Gergely, György

2011-01-01

We propose that the cognitive mechanisms that enable the transmission of cultural knowledge by communication between individuals constitute a system of ‘natural pedagogy’ in humans, and represent an evolutionary adaptation along the hominin lineage. We discuss three kinds of arguments that support this hypothesis. First, natural pedagogy is likely to be human-specific: while social learning and communication are both widespread in non-human animals, we know of no example of social learning by communication in any other species apart from humans. Second, natural pedagogy is universal: despite the huge variability in child-rearing practices, all human cultures rely on communication to transmit to novices a variety of different types of cultural knowledge, including information about artefact kinds, conventional behaviours, arbitrary referential symbols, cognitively opaque skills and know-how embedded in means-end actions. Third, the data available on early hominin technological culture are more compatible with the assumption that natural pedagogy was an independently selected adaptive cognitive system than considering it as a by-product of some other human-specific adaptation, such as language. By providing a qualitatively new type of social learning mechanism, natural pedagogy is not only the product but also one of the sources of the rich cultural heritage of our species. PMID:21357237

The evolutionary theory of asymmetry by V. Geodakyan

Science.gov (United States)

Geodakyan, Sergey V.

2015-08-01

For more than 150 years, all biological theories, including those of C. Darwin and Mendel, were based on the idea of synchronous evolution. They fit for unitary monomodal systems (asexual, symmetrical) but do not work for binary (dioecious, asymmetrical) ones. Examples of such binary conjugated differentiations are two sexes, DNA-proteins, autosomes-sex chromosomes, right and left brain hemispheres, and hands. For their understanding, "asynchronous" theories are needed. Such theories were proposed by Russian theoretical biologist Vigen A. Geodakyan for sexual, brain and body, and chromosomal differentiations. All theories are interconnected and are based on the principle of conjugated subsystems. This article covers the basic tenets of the evolutionary theory of asymmetry and answers the following questions: What benefits does lateralization provide? What logic, what principle is it based on? Why do brain hemispheres control the opposite sides of the body? Why laterality is closely related to sex? What are the biological prerequisites of terrorism?

Evolutionary Biology Today

Indian Academy of Sciences (India)

Hindi and English. Port 1. Resonance, Vo1.7 ... they use. Of course, many evolutionary biologists do work with fossils or DNA, or both, but there are also large numbers of ... The first major division that I like to make is between studies focussed ...

The evolutionary rate dynamically tracks changes in HIV-1 epidemics

Energy Technology Data Exchange (ETDEWEB)

Maljkovic-berry, Irina [Los Alamos National Laboratory; Athreya, Gayathri [Los Alamos National Laboratory; Daniels, Marcus [Los Alamos National Laboratory; Bruno, William [Los Alamos National Laboratory; Korber, Bette [Los Alamos National Laboratory; Kuiken, Carla [Los Alamos National Laboratory; Ribeiro, Ruy M [Los Alamos National Laboratory

2009-01-01

Large-sequence datasets provide an opportunity to investigate the dynamics of pathogen epidemics. Thus, a fast method to estimate the evolutionary rate from large and numerous phylogenetic trees becomes necessary. Based on minimizing tip height variances, we optimize the root in a given phylogenetic tree to estimate the most homogenous evolutionary rate between samples from at least two different time points. Simulations showed that the method had no bias in the estimation of evolutionary rates and that it was robust to tree rooting and topological errors. We show that the evolutionary rates of HIV-1 subtype B and C epidemics have changed over time, with the rate of evolution inversely correlated to the rate of virus spread. For subtype B, the evolutionary rate slowed down and tracked the start of the HAART era in 1996. Subtype C in Ethiopia showed an increase in the evolutionary rate when the prevalence increase markedly slowed down in 1995. Thus, we show that the evolutionary rate of HIV-1 on the population level dynamically tracks epidemic events.

The First Joke: Exploring the Evolutionary Origins of Humor

Directory of Open Access Journals (Sweden)

Joseph Polimeni

2006-01-01

Full Text Available Humor is a complex cognitive function which often leads to laughter. Contemporary humor theorists have begun to formulate hypotheses outlining the possible innate cognitive structures underlying humor. Humor's conspicuous presence in the behavioral repertoire of humankind invites adaptive explanations. This article explores the possible adaptive features of humor and ponders its evolutionary path through hominid history. Current humor theories and previous evolutionary ideas on humor are reviewed. In addition, scientific fields germane to the evolutionary study of humor are examined: animal models, genetics, children's humor, humor in pathological conditions, neurobiology, humor in traditional societies and cognitive archeology. Candidate selection pressures and associated evolutionary mechanisms are considered. The authors conclude that several evolutionary-related topics such as the origins of language, cognition underlying spiritual feelings, hominid group size, and primate teasing could have special relevance to the origins of humor.

Predicting loss of evolutionary history: Where are we?

Science.gov (United States)

Veron, Simon; Davies, T Jonathan; Cadotte, Marc W; Clergeau, Philippe; Pavoine, Sandrine

2017-02-01

The Earth's evolutionary history is threatened by species loss in the current sixth mass extinction event in Earth's history. Such extinction events not only eliminate species but also their unique evolutionary histories. Here we review the expected loss of Earth's evolutionary history quantified by phylogenetic diversity (PD) and evolutionary distinctiveness (ED) at risk. Due to the general paucity of data, global evolutionary history losses have been predicted for only a few groups, such as mammals, birds, amphibians, plants, corals and fishes. Among these groups, there is now empirical support that extinction threats are clustered on the phylogeny; however this is not always a sufficient condition to cause higher loss of phylogenetic diversity in comparison to a scenario of random extinctions. Extinctions of the most evolutionarily distinct species and the shape of phylogenetic trees are additional factors that can elevate losses of evolutionary history. Consequently, impacts of species extinctions differ among groups and regions, and even if global losses are low within large groups, losses can be high among subgroups or within some regions. Further, we show that PD and ED are poorly protected by current conservation practices. While evolutionary history can be indirectly protected by current conservation schemes, optimizing its preservation requires integrating phylogenetic indices with those that capture rarity and extinction risk. Measures based on PD and ED could bring solutions to conservation issues, however they are still rarely used in practice, probably because the reasons to protect evolutionary history are not clear for practitioners or due to a lack of data. However, important advances have been made in the availability of phylogenetic trees and methods for their construction, as well as assessments of extinction risk. Some challenges remain, and looking forward, research should prioritize the assessment of expected PD and ED loss for more taxonomic

How evolutionary principles improve the understanding of human health and disease.

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Gluckman, Peter D; Low, Felicia M; Buklijas, Tatjana; Hanson, Mark A; Beedle, Alan S

2011-03-01

An appreciation of the fundamental principles of evolutionary biology provides new insights into major diseases and enables an integrated understanding of human biology and medicine. However, there is a lack of awareness of their importance amongst physicians, medical researchers, and educators, all of whom tend to focus on the mechanistic (proximate) basis for disease, excluding consideration of evolutionary (ultimate) reasons. The key principles of evolutionary medicine are that selection acts on fitness, not health or longevity; that our evolutionary history does not cause disease, but rather impacts on our risk of disease in particular environments; and that we are now living in novel environments compared to those in which we evolved. We consider these evolutionary principles in conjunction with population genetics and describe several pathways by which evolutionary processes can affect disease risk. These perspectives provide a more cohesive framework for gaining insights into the determinants of health and disease. Coupled with complementary insights offered by advances in genomic, epigenetic, and developmental biology research, evolutionary perspectives offer an important addition to understanding disease. Further, there are a number of aspects of evolutionary medicine that can add considerably to studies in other domains of contemporary evolutionary studies.

Theoretical Approaches in Evolutionary Ecology: Environmental Feedback as a Unifying Perspective.

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Lion, Sébastien

2018-01-01

Evolutionary biology and ecology have a strong theoretical underpinning, and this has fostered a variety of modeling approaches. A major challenge of this theoretical work has been to unravel the tangled feedback loop between ecology and evolution. This has prompted the development of two main classes of models. While quantitative genetics models jointly consider the ecological and evolutionary dynamics of a focal population, a separation of timescales between ecology and evolution is assumed by evolutionary game theory, adaptive dynamics, and inclusive fitness theory. As a result, theoretical evolutionary ecology tends to be divided among different schools of thought, with different toolboxes and motivations. My aim in this synthesis is to highlight the connections between these different approaches and clarify the current state of theory in evolutionary ecology. Central to this approach is to make explicit the dependence on environmental dynamics of the population and evolutionary dynamics, thereby materializing the eco-evolutionary feedback loop. This perspective sheds light on the interplay between environmental feedback and the timescales of ecological and evolutionary processes. I conclude by discussing some potential extensions and challenges to our current theoretical understanding of eco-evolutionary dynamics.

What Is Sexual Orientation All About? Explaining an Evolutionary Paradox

OpenAIRE

Brad Bowins

2015-01-01

Numerous psychological, biological, and evolutionary theories have been proposed to explain sexual orientation. For a theory to be valid it must account for the evolutionary or Darwinian paradox of how homosexual behavior seemingly blocking evolutionary fitness could have evolved. Typically it is only evolutionary based theories that attempt to address this issue. All theories proposed to date have limitations, a major one being that they tend to be specific for male or female sexual orientat...

Impact of novelty and type of material on recognition in healthy older adults and persons with mild cognitive impairment.

Science.gov (United States)

Belleville, Sylvie; Ménard, Marie-Claude; Lepage, Emilie

2011-08-01

The goal of this study was to assess the effect of novelty on correct recognition (hit minus false alarms) and on recollection and familiarity processes in normal aging and amnestic mild cognitive impairment (MCI). Recognition tasks compared well-known and novel stimuli in the verbal domain (words vs. pseudowords) and in the musical domain (well-known vs. novel melodies). Results indicated that novel materials associated with lower correct recognition and lower recollection, an effect that can be related to its lower amenability to elaborative encoding in comparison with well-known items. Results also indicated that normal aging impairs recognition of well-known items, whereas MCI impairs recognition of novel items only. Healthy older adults showed impaired recollection and familiarity relative to younger controls and individuals with MCI showed impaired recollection relative to healthy older adults. The recollection deficit in healthy older adults and persons with MCI and their impaired recognition of well-known items is compatible with the difficulty both groups have in encoding information in an elaborate manner. In turn, familiarity deficit could be related to impaired frontal functioning. Therefore, novelty of material has a differential impact on recognition in persons with age-related memory disorders. Copyright © 2011 Elsevier Ltd. All rights reserved.

The evolutionary implications of epigenetic inheritance.

Science.gov (United States)

Jablonka, Eva

2017-10-06

The Modern Evolutionary Synthesis (MS) forged in the mid-twentieth century was built on a notion of heredity that excluded soft inheritance, the inheritance of the effects of developmental modifications. However, the discovery of molecular mechanisms that generate random and developmentally induced epigenetic variations is leading to a broadening of the notion of biological heredity that has consequences for ideas about evolution. After presenting some old challenges to the MS that were raised, among others, by Karl Popper, I discuss recent research on epigenetic inheritance, which provides experimental and theoretical support for these challenges. There is now good evidence that epigenetic inheritance is ubiquitous and is involved in adaptive evolution and macroevolution. I argue that the many evolutionary consequences of epigenetic inheritance open up new research areas and require the extension of the evolutionary synthesis beyond the current neo-Darwinian model.

Evolutionary Computing for Intelligent Power System Optimization and Control

DEFF Research Database (Denmark)

This new book focuses on how evolutionary computing techniques benefit engineering research and development tasks by converting practical problems of growing complexities into simple formulations, thus largely reducing development efforts. This book begins with an overview of the optimization the...... theory and modern evolutionary computing techniques, and goes on to cover specific applications of evolutionary computing to power system optimization and control problems....

Micro-evolutionary responses and adaptive costs of Caenorhabditis elegans populations exposed to environmental stress

International Nuclear Information System (INIS)

Dutilleul, M.

2013-01-01

The contemporary evolution of organisms is largely dependent on anthropogenic disturbances. In particular, pollution amplifies the intensity or the quantity of selection pressures on populations. However, these changes may have negative effects on the life, growth and reproduction of individuals, the demographics of the population, and its phenotypic and genetic characteristics over generations. Thus, micro-evolutionary changes are likely to occur in response to selection pressures. These phenomenon lead to collateral damages: adaptive costs. For example, a reduction of genetic diversity in a population entails a decrease in its potential to adapt to other stressors. Populations can be more susceptible to many environmental changes, especially with the increase of human activities. Hence in an ecological risk assessment, studying the mechanisms of action and immediate adverse effects of pollutants on organisms is no longer sufficient. It is also necessary to expand our knowledge on the evolution of populations in polluted environment. In this context, our study aims to determine the micro-evolutionary response of Caenorhabditis elegans populations exposed to environmental stressors, and to measure their costs of adaptation. Populations were experimentally exposed for 22 generations to a high concentration of uranium, sodium chloride or an alternation of both these pollutants. The analysis of phenotypic and genetic changes, observed through measures of life history traits, was accomplished using several quantitative genetics techniques. In particular, we confirmed the genetic differentiation between populations with an increase of resistance in populations exposed to different pollutions. The speed of evolutionary responses depended on the conditions of exposure and their effects on the expression of the genetic structure of traits (e.g. G matrix). Micro-evolutionary changes were linked to costs of adaptation, such as reduced fertility in stressful novel

The great opportunity: Evolutionary applications to medicine and public health.

Science.gov (United States)

Nesse, Randolph M; Stearns, Stephen C

2008-02-01

Evolutionary biology is an essential basic science for medicine, but few doctors and medical researchers are familiar with its most relevant principles. Most medical schools have geneticists who understand evolution, but few have even one evolutionary biologist to suggest other possible applications. The canyon between evolutionary biology and medicine is wide. The question is whether they offer each other enough to make bridge building worthwhile. What benefits could be expected if evolution were brought fully to bear on the problems of medicine? How would studying medical problems advance evolutionary research? Do doctors need to learn evolution, or is it valuable mainly for researchers? What practical steps will promote the application of evolutionary biology in the areas of medicine where it offers the most? To address these questions, we review current and potential applications of evolutionary biology to medicine and public health. Some evolutionary technologies, such as population genetics, serial transfer production of live vaccines, and phylogenetic analysis, have been widely applied. Other areas, such as infectious disease and aging research, illustrate the dramatic recent progress made possible by evolutionary insights. In still other areas, such as epidemiology, psychiatry, and understanding the regulation of bodily defenses, applying evolutionary principles remains an open opportunity. In addition to the utility of specific applications, an evolutionary perspective fundamentally challenges the prevalent but fundamentally incorrect metaphor of the body as a machine designed by an engineer. Bodies are vulnerable to disease - and remarkably resilient - precisely because they are not machines built from a plan. They are, instead, bundles of compromises shaped by natural selection in small increments to maximize reproduction, not health. Understanding the body as a product of natural selection, not design, offers new research questions and a framework for

Selectionist and evolutionary approaches to brain function: a critical appraisal

Directory of Open Access Journals (Sweden)

Chrisantha Thomas Fernando

2012-04-01

Full Text Available We consider approaches to brain dynamics and function that have been claimed to be Darwinian. These include Edelman’s theory of neuronal group selection, Changeux’s theory of synaptic selection and selective stabilization of pre-representations, Seung’s Darwinian synapse, Loewenstein’s synaptic melioration, Adam’s selfish synapse and Calvin’s replicating activity patterns. Except for the last two, the proposed mechanisms are selectionist but not truly Darwinian, because no replicators with information transfer to copies and hereditary variation can be identified in them. All of them fit, however, a generalized selectionist framework conforming to the picture of Price’s covariance formulation, which deliberately was not specific even to selection in biology, and therefore does not imply an algorithmic picture of biological evolution. Bayesian models and reinforcement learning are formally in agreement with selection dynamics. A classification of search algorithms is shown to include Darwinian replicators (evolutionary units with multiplication, heredity and variability as the most powerful mechanism in a sparsely occupied search space. Examples of why parallel competitive search with information transfer among the units is efficient are given. Finally, we review our recent attempts to construct and analyze simple models of true Darwinian evolutionary units in the brain in terms of connectivity and activity copying of neuronal groups. Although none of the proposed neuronal replicators include miraculous mechanisms, their identification remains a challenge but also a great promise.

EVOLUTIONARY THEORY AND THE MARKET COMPETITION

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SIRGHI Nicoleta

2014-12-01

Full Text Available Evolutionary theory study of processes that transform economy for firms, institutions, industries, employment, production, trade and growth within, through the actions of diverse agents from experience and interactions, using evolutionary methodology. Evolutionary theory analyses the unleashing of a process of technological and institutional innovation by generating and testing a diversity of ideas which discover and accumulate more survival value for the costs incurred than competing alternatives.This paper presents study the behavior of the firms on the market used the evolutionary theory.The paper is to present in full the developments that have led to the re-assessment of theories of firms starting from the criticism on Coase's theory based on the lack of testable hypotheses and on non-operative definition of transaction costs. In the literature in the field studies on firms were allotted a secondary place for a long period of time, to date the new theories of the firm hold a dominant place in the firms’ economic analysis. In an article, published in 1937, Ronald H. Coase identified the main sources of the cost of using the market mechanism. The firms theory represent a issue intensively studied in the literature in the field, regarding the survival, competitiveness and innovation of firm on the market. The research of Nelson and Winter, “An Evolutionary Theory of Economic Change” (1982 is the starting point for a modern literature in the field which considers the approach of the theory of the firm from an evolutionary perspective. Nelson and Winter have shown that the “orthodox” theory, is objectionable primarily by the fact that the hypothesis regarding profit maximization has a normative character and is not valid in any situation. Nelson and Winter reconsidered their microeconomic analysis showing that excessive attention should not be paid to market equilibrium but rather to dynamic processes resulting from irreversible

Wolbachia age-sex-specific density in Aedes albopictus: a host evolutionary response to cytoplasmic incompatibility?

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Pablo Tortosa

2010-03-01

Full Text Available Wolbachia bacteria have invaded many arthropod species by inducing Cytoplasmic Incompatibility (CI. These symbionts represent fascinating objects of study for evolutionary biologists, but also powerful potential biocontrol agents. Here, we assess the density dynamics of Wolbachia infections in males and females of the mosquito Aedes albopitcus, an important vector of human pathogens, and interpret the results within an evolutionary framework.Wolbachia densities were measured in natural populations and in age controlled mosquitoes using quantitative PCR. We show that the density dynamics of the wAlbA Wolbachia strain infecting Aedes albopictus drastically differ between males and females, with a very rapid decay of infection in males only.Theory predicts that Wolbachia and its hosts should cooperate to improve the transmission of infection to offspring, because only infected eggs are protected from the effects of CI. However, incompatible matings effectively lower the fertility of infected males, so that selection acting on the host genome should tend to reduce the expression of CI in males, for example, by reducing infection density in males before sexual maturation. The rapid decay of one Wolbachia infection in Aedes albopictus males, but not in females, is consistent with this prediction. We suggest that the commonly observed reduction in CI intensity with male age reflects a similar evolutionary process. Our results also highlight the importance of monitoring infection density dynamics in both males and females to assess the efficiency of Wolbachia-based control strategies.

Multifactorial determinants of target and novelty-evoked P300 amplitudes in children of addicted parents.

Directory of Open Access Journals (Sweden)

Anja S Euser

Full Text Available BACKGROUND: Although P300 amplitude reductions constitute a persistent finding in children of addicted parents, relatively little is known about the specificity of this finding. The major aim of this study was to investigate the association between parental rearing, adverse life events, stress-reactivity, substance use and psychopathology on the one hand, and P300 amplitude in response to both target and novel distracter stimuli on the other hand. Moreover, we assessed whether risk group status (i.e., having a parental history of Substance Use Disorders [SUD] uniquely contributed to P300 amplitude variation above and beyond these other variables. METHODS: Event-related potentials were recorded in high-risk adolescents with a parental history of SUD (HR;n=80 and normal-risk controls (NR;n=100 while performing a visual Novelty Oddball paradigm. Stress-evoked cortisol levels were assessed and parenting, life adversities, substance use and psychopathology were examined by using self-reports. RESULTS: HR adolescents displayed smaller P300 amplitudes in response to novel- and to target stimuli than NR controls, while the latter only approached significance. Interestingly, the effect of having a parental history of SUD on target-P300 disappeared when all other variables were taken into account. Externalizing problem behavior was a powerful predictor of target-P300. In contrast, risk group status uniquely predicted novelty-P300 amplitude reductions above and beyond all other factors. CONCLUSION: Overall, the present findings suggest that the P300 amplitude reduction to novel stimuli might be a more specific endophenotype for SUD than the target-P300 amplitude. This pattern of results underscores the importance of conducting multifactorial assessments when examining important cognitive processes in at-risk adolescents.

Evolutionary epistemology, rationality, and the sociology of knowledge

CERN Document Server

Bartley, W W

1993-01-01

This collection of essays in support of the theory of evolutionary epistemology includes articles by Karl Popper, Peter Munz and Gerhard Vollmer. This volume attempts to show how an evolutionary and non-justificational approach affects the sociology of knowledge.

Molluscan Evolutionary Development

DEFF Research Database (Denmark)

Wanninger, Andreas Wilhelm Georg; Koop, Damien; Moshel-Lynch, Sharon

2008-01-01

Brought together by Winston F. Ponder and David R. Lindberg, thirty-six experts on the evolution of the Mollusca provide an up-to-date review of its evolutionary history. The Mollusca are the second largest animal phylum and boast a fossil record of over 540 million years. They exhibit remarkable...

Evolutionary genomics and HIV restriction factors.

Science.gov (United States)

Pyndiah, Nitisha; Telenti, Amalio; Rausell, Antonio

2015-03-01

To provide updated insights into innate antiviral immunity and highlight prototypical evolutionary features of well characterized HIV restriction factors. Recently, a new HIV restriction factor, Myxovirus resistance 2, has been discovered and the region/residue responsible for its activity identified using an evolutionary approach. Furthermore, IFI16, an innate immunity protein known to sense several viruses, has been shown to contribute to the defense to HIV-1 by causing cell death upon sensing HIV-1 DNA. Restriction factors against HIV show characteristic signatures of positive selection. Different patterns of accelerated sequence evolution can distinguish antiviral strategies--offense or defence--as well as the level of specificity of the antiviral properties. Sequence analysis of primate orthologs of restriction factors serves to localize functional domains and sites responsible for antiviral action. We use recent discoveries to illustrate how evolutionary genomic analyses help identify new antiviral genes and their mechanisms of action.

Evolutionary rates of mitochondrial genomes correspond to diversification rates and to contemporary species richness in birds and reptiles

Science.gov (United States)

Eo, Soo Hyung; DeWoody, J. Andrew

2010-01-01

Rates of biological diversification should ultimately correspond to rates of genome evolution. Recent studies have compared diversification rates with phylogenetic branch lengths, but incomplete phylogenies hamper such analyses for many taxa. Herein, we use pairwise comparisons of confamilial sauropsid (bird and reptile) mitochondrial DNA (mtDNA) genome sequences to estimate substitution rates. These molecular evolutionary rates are considered in light of the age and species richness of each taxonomic family, using a random-walk speciation–extinction process to estimate rates of diversification. We find the molecular clock ticks at disparate rates in different families and at different genes. For example, evolutionary rates are relatively fast in snakes and lizards, intermediate in crocodilians and slow in turtles and birds. There was also rate variation across genes, where non-synonymous substitution rates were fastest at ATP8 and slowest at CO3. Family-by-gene interactions were significant, indicating that local clocks vary substantially among sauropsids. Most importantly, we find evidence that mitochondrial genome evolutionary rates are positively correlated with speciation rates and with contemporary species richness. Nuclear sequences are poorly represented among reptiles, but the correlation between rates of molecular evolution and species diversification also extends to 18 avian nuclear genes we tested. Thus, the nuclear data buttress our mtDNA findings. PMID:20610427

Observational and evolutionary aspects of Wolf-Rayet stars

International Nuclear Information System (INIS)

Vanbeveren, D.

1980-01-01

The author considers (i) the binary status of Wolf-Rayet stars, (ii) the evolutionary status of Wolf-Rayet stars, (iii) the chemical abundances of Wolf-Rayet stars and (iv) evolutionary models for some known Wolf-Rayet systems. (G.T.H.)

Ancestral assumptions and the clinical uncertainty of evolutionary medicine.

Science.gov (United States)

Cournoyea, Michael

2013-01-01

Evolutionary medicine is an emerging field of medical studies that uses evolutionary theory to explain the ultimate causes of health and disease. Educational tools, online courses, and medical school modules are being developed to help clinicians and students reconceptualize health and illness in light of our evolutionary past. Yet clinical guidelines based on our ancient life histories are epistemically weak, relying on the controversial assumptions of adaptationism and advocating a strictly biophysical account of health. To fulfill the interventionist goals of clinical practice, it seems that proximate explanations are all we need to develop successful diagnostic and therapeutic guidelines. Considering these epistemic concerns, this article argues that the clinical relevance of evolutionary medicine remains uncertain at best.

The human dark side: evolutionary psychology and original sin.

Science.gov (United States)

Lee, Joseph; Theol, M

2014-04-01

Human nature has a dark side, something important to religions. Evolutionary psychology has been used to illuminate the human shadow side, although as a discipline it has attracted criticism. This article seeks to examine the evolutionary psychology's understanding of human nature and to propose an unexpected dialog with an enduring account of human evil known as original sin. Two cases are briefly considered: murder and rape. To further the exchange, numerous theoretical and methodological criticisms and replies of evolutionary psychology are explored jointly with original sin. Evolutionary psychology can partner with original sin since they share some theoretical likenesses and together they offer insights into the nature of what it means to be human.

Animal egg as evolutionary innovation: a solution to the "embryonic hourglass" puzzle.

Science.gov (United States)

Newman, Stuart A

2011-11-15

The evolutionary origin of the egg stage of animal development presents several difficulties for conventional developmental and evolutionary narratives. If the egg's internal organization represents a template for key features of the developed organism, why can taxa within a given phylum exhibit very different egg types, pass through a common intermediate morphology (the so-called "phylotypic stage"), only to diverge again, thus exemplifying the embryonic "hourglass"? Moreover, if different egg types typically represent adaptations to different environmental conditions, why do birds and mammals, for example, have such vastly different eggs with respect to size, shape, and postfertilization dynamics, whereas all these features are more similar for ascidians and mammals? Here, I consider the possibility that different body plans had their origin in self-organizing physical processes in ancient clusters of cells, and suggest that eggs represented a set of independent evolutionary innovations subsequently inserted into the developmental trajectories of such aggregates. I first describe how "dynamical patterning modules" (DPMs) associations between components of the metazoan developmental-genetic toolkit and certain physical processes and effects may have organized primitive animal body plans independently of an egg stage. Next, I describe how adaptive specialization of cells released from such aggregates could have become "proto-eggs," which regenerated the parental cell clusters by cleavage, conserving the characteristic DPMs available to a lineage. Then, I show how known processes of cytoplasmic reorganization following fertilization are often based on spontaneous, self-organizing physical effects ("egg-patterning processes": EPPs). I suggest that rather than acting as developmental blueprints or prepatterns, the EPPs refine the phylotypic body plans determined by the DPMs by setting the boundary and initial conditions under which these multicellular patterning