WorldWideScience

Sample records for biological evolution

  1. Consciousness and biological evolution.

    Science.gov (United States)

    Lindahl, B I

    1997-08-21

    It has been suggested that if the preservation and development of consciousness in the biological evolution is a result of natural selection, it is plausible that consciousness not only has been influenced by neural processes, but has had a survival value itself; and it could only have had this, if it had also been efficacious. This argument for mind-brain interaction is examined, both as the argument has been developed by William James and Karl Popper and as it has been discussed by C.D. Broad. The problem of identifying mental phenomena with certain neural phenomena is also addressed. The main conclusion of the analysis is that an explanation of the evolution of consciousness in Darwinian terms of natural selection does not rule out that consciousness may have evolved as a mere causally inert effect of the evolution of the nervous system, or that mental phenomena are identical with certain neural phenomena. However, the interactionistic theory still seems, more plausible and more fruitful for other reasons brought up in the discussion.

  2. Evolution, Entropy, & Biological Information

    Science.gov (United States)

    Peterson, Jacob

    2014-01-01

    A logical question to be expected from students: "How could life develop, that is, change, evolve from simple, primitive organisms into the complex forms existing today, while at the same time there is a generally observed decline and disorganization--the second law of thermodynamics?" The explanations in biology textbooks relied upon by…

  3. Computational optimization and biological evolution.

    Science.gov (United States)

    Goryanin, Igor

    2010-10-01

    Modelling and optimization principles become a key concept in many biological areas, especially in biochemistry. Definitions of objective function, fitness and co-evolution, although they differ between biology and mathematics, are similar in a general sense. Although successful in fitting models to experimental data, and some biochemical predictions, optimization and evolutionary computations should be developed further to make more accurate real-life predictions, and deal not only with one organism in isolation, but also with communities of symbiotic and competing organisms. One of the future goals will be to explain and predict evolution not only for organisms in shake flasks or fermenters, but for real competitive multispecies environments.

  4. Student Teachers' Approaches to Teaching Biological Evolution

    Science.gov (United States)

    Borgerding, Lisa A.; Klein, Vanessa A.; Ghosh, Rajlakshmi; Eibel, Albert

    2015-01-01

    Evolution is fundamental to biology and scientific literacy, but teaching high school evolution is often difficult. Evolution teachers face several challenges including limited content knowledge, personal conflicts with evolution, expectations of resistance, concerns about students' conflicts with religion, and curricular constraints. Evolution…

  5. Africa and Precambrian biological evolution

    Directory of Open Access Journals (Sweden)

    A. H. Knoll

    1983-12-01

    Full Text Available African sedimentary rocks and their contained fossils have played a fundamental role in the unravelling of Precambrian biological history. Various lines of evidence including stromatolites, filamentous and coccoidal microfossils, stable isotope ratios, organic carbon distribution, and oxide facies iron formation suggest that a complex prokaryotic ecosystem fueled by photosynthesis, and perhaps including aerobic photoautotrophs, existed as early as 3 500 m.y. ago. The primary sources of data on early Archean life are rock sequences in southern Africa and Australia. The diversity of later Archean (ca. 2 700 m.y. communities is attested to by abundant and varied stromatolites found in Zimbabwe. The extensive growth and consolidation of continents that heralded the Proterozoic Eon had profound effects on the earth’s biota. Primary productivity must have increased substantially, resulting in the establishment of an 02-rich atmosphere, and, subsequently, the radiation of aerobic respirers. Southern African sequences provide critical evidence bearing on this crust/atmosphere/biota interaction; however, the best known microfossils of this age come from North America. Upper Proterozoic sedimentary rocks abound in Africa. Stromatolites from northwestern Africa have been well studied; however, microfossil occurrences remain but sketchily described. Contemporaneous sequences from Scandinavia and Australia document the initial radiation of eukaryotes in the planktonic realm, as well as a terminal Precambrian episode of extinction among plankters. Early heterotrophic protists are known from several continents. The Nama Group of South West Africa/Namibia contains important evidence of early invertebrates. In general, Precambrian evolution can be viewed as a series of increasingly elevated biological plateaus connected by steps marking relatively short periods of evolutionary innovation and radiation. With each step, communities have increased in complexity

  6. A comparison of biological and cultural evolution.

    Science.gov (United States)

    Portin, Petter

    2015-03-01

    This review begins with a definition of biological evolution and a description of its general principles. This is followed by a presentation of the biological basis of culture, specifically the concept of social selection. Further, conditions for cultural evolution are proposed, including a suggestion for language being the cultural replicator corresponding to the concept of the gene in biological evolution. Principles of cultural evolution are put forward and compared to the principles of biological evolution. Special emphasis is laid on the principle of selection in cultural evolution, including presentation of the concept of cultural fitness. The importance of language as a necessary condition for cultural evolution is stressed. Subsequently, prime differences between biological and cultural evolution are presented, followed by a discussion on interaction of our genome and our culture. The review aims at contributing to the present discussion concerning the modern development of the general theory of evolution, for example by giving a tentative formulation of the necessary and sufficient conditions for cultural evolution, and proposing that human creativity and mind reading or theory of mind are motors specific for it. The paper ends with the notion of the still ongoing coevolution of genes and culture.

  7. A comparison of biological and cultural evolution

    Indian Academy of Sciences (India)

    Petter Portin

    2015-03-01

    This review begins with a definition of biological evolution and a description of its general principles. This is followed by a presentation of the biological basis of culture, specifically the concept of social selection. Further, conditions for cultural evolution are proposed, including a suggestion for language being the cultural replicator corresponding to the concept of the gene in biological evolution. Principles of cultural evolution are put forward and compared to the principles of biological evolution. Special emphasis is laid on the principle of selection in cultural evolution, including presentation of the concept of cultural fitness. The importance of language as a necessary condition for cultural evolution is stressed. Subsequently, prime differences between biological and cultural evolution are presented, followed by a discussion on interaction of our genome and our culture. The review aims at contributing to the present discussion concerning the modern development of the general theory of evolution, for example by giving a tentative formulation of the necessary and sufficient conditions for cultural evolution, and proposing that human creativity and mind reading or theory of mind are motors specific for it. The paper ends with the notion of the still ongoing coevolution of genes and culture.

  8. Student Teachers' Approaches to Teaching Biological Evolution

    Science.gov (United States)

    Borgerding, Lisa A.; Klein, Vanessa A.; Ghosh, Rajlakshmi; Eibel, Albert

    2015-06-01

    Evolution is fundamental to biology and scientific literacy, but teaching high school evolution is often difficult. Evolution teachers face several challenges including limited content knowledge, personal conflicts with evolution, expectations of resistance, concerns about students' conflicts with religion, and curricular constraints. Evolution teaching can be particularly challenging for student teachers who are just beginning to gain pedagogical knowledge and pedagogical content knowledge related to evolution teaching and who seek approval from university supervisors and cooperating teachers. Science teacher educators need to know how to best support student teachers as they broach the sometimes daunting task of teaching evolution within student teaching placements. This multiple case study report documents how three student teachers approached evolution instruction and what influenced their approaches. Data sources included student teacher interviews, field note observations for 4-5 days of evolution instruction, and evolution instructional artifacts. Data were analyzed using grounded theory approaches to develop individual cases and a cross-case analysis. Seven influences (state exams and standards, cooperating teacher, ideas about teaching and learning, concerns about evolution controversy, personal commitment to evolution, knowledge and preparation for teaching evolution, and own evolution learning experiences) were identified and compared across cases. Implications for science teacher preparation and future research are provided.

  9. Dissipative Structures and Biological Evolution

    Science.gov (United States)

    Brändas, E. J.

    This contribution celebrates Prof. Manuel G. Velarde's exceptional accomplishments in the science of Complex Systems and Non-Linear Dynamics in connection with his seventieth anniversary and subsequent retirement from the Instituto Pluridisciplinar de la Universidad Complutense de Madrid (UCM). In this commemoration I will discuss my provisional yet unique association with Manuel over the years. Although viewing scientific problems from differing ends of the micro-macro spectrum I believe our relationship has been mutually beneficial. In this account I will, in a few words, describe recent developments in our program to attack complicated issues on the borderline between physics and biology. Concrete overlapping interests incorporate problems related to strongly correlated systems like superconductivity as well as currently disputed issues pertaining to biological concepts and the unity of physical theory. In summary we will give examples of such wide-ranging proposals comprising potential avenues providing feasible platforms for the future.

  10. Africa and Precambrian biological evolution

    OpenAIRE

    Knoll, A.H

    1983-01-01

    African sedimentary rocks and their contained fossils have played a fundamental role in the unravelling of Precambrian biological history. Various lines of evidence including stromatolites, filamentous and coccoidal microfossils, stable isotope ratios, organic carbon distribution, and oxide facies iron formation suggest that a complex prokaryotic ecosystem fueled by photosynthesis, and perhaps including aerobic photoautotrophs, existed as early as 3 500 m.y. ago. The primary sources of data o...

  11. Worldviews and evolution in the biology classroom

    NARCIS (Netherlands)

    Schilders, M.; Sloep, P.; Peled, E.; Boersma, K.T.

    2009-01-01

    This study examined what worldviews are present among Dutch students and teachers and how the students cope with scientific knowledge acquired in the biology classroom. Furthermore, we investigated what learning and teaching strategies teachers adopt when they teach about evolution and worldviews. F

  12. Biological evolution in a multidimensional fitness landscape.

    Science.gov (United States)

    Saakian, David B; Kirakosyan, Zara; Hu, Chin-Kun

    2012-09-01

    We considered a multiblock molecular model of biological evolution, in which fitness is a function of the mean types of alleles located at different parts (blocks) of the genome. We formulated an infinite population model with selection and mutation, and calculated the mean fitness. For the case of recombination, we formulated a model with a multidimensional fitness landscape (the dimension of the space is equal to the number of blocks) and derived a theorem about the dynamics of initially narrow distribution. We also considered the case of lethal mutations. We also formulated the finite population version of the model in the case of lethal mutations. Our models, derived for the virus evolution, are interesting also for the statistical mechanics and the Hamilton-Jacobi equation as well.

  13. [Around biological evolution. Reflections of a physicist].

    Science.gov (United States)

    Sanchez-Palencia, Evariste

    2016-01-01

    This text is the written version of a talk at the Société de Biologie on February 17, 2016. It contains reflections of a non-biologist scientist on general problems of biological evolution, including the kind of causality involved, the ideas emerging from it, in particular the constructive and structuring character of phenomena such as predation, the role of stability and attractors. This leads to a larger reflection on dialectics, the general framework of evolving processes, which overpasses formal logic and instantaneousness.

  14. Archaea: Evolution, Physiology, and Molecular Biology

    DEFF Research Database (Denmark)

    Introduced by Crafoord Prize winner Carl Woese, this volume combines reviews of the major developments in archaeal research over the past 10-15 years with more specialized articles dealing with important recent breakthroughs. Drawing on major themes presented at the June 2005 meeting held in Muni...... and technological context, and include accounts of cutting-edge research developments. The book spans archaeal evolution, physiology, and molecular and cellular biology and will be an essential reference for both graduate students and researchers....... to honor the archaea pioneers Wolfram Zillig and Karl O. Stetter, the book provides a thorough survey of the field from its controversial beginnings to its ongoing expansion to include aspects of eukaryotic biology. The editors have assembled articles from the premier researchers in this rapidly burgeoning...

  15. How does evolution tune biological noise ?

    Directory of Open Access Journals (Sweden)

    Magali eRichard

    2014-10-01

    Full Text Available Part of molecular and phenotypic differences between individual cells, between body parts, or between individuals can result from biological noise. This source of variation is becoming more and more apparent thanks to the recent advances in dynamic imaging and single-cell analysis. Some of these studies showed that the link between genotype and phenotype is not strictly deterministic. Mutations can change various statistical properties of a biochemical reaction, and thereby the probability of a trait outcome. The fact that they can modulate phenotypic noise brings up an intriguing question: how may selection act on these mutations? In this review, we approach this question by first covering the evidence that biological noise is under genetic control and therefore a substrate for evolution. We then sequentially inspect the possibilities of negative, neutral and positive selection for mutations increasing biological noise. Finally, we hypothesize on the specific case of H2A.Z, which was shown to both buffer phenotypic noise and modulate transcriptional efficiency.

  16. Modeling Co-evolution of Speech and Biology.

    Science.gov (United States)

    de Boer, Bart

    2016-04-01

    Two computer simulations are investigated that model interaction of cultural evolution of language and biological evolution of adaptations to language. Both are agent-based models in which a population of agents imitates each other using realistic vowels. The agents evolve under selective pressure for good imitation. In one model, the evolution of the vocal tract is modeled; in the other, a cognitive mechanism for perceiving speech accurately is modeled. In both cases, biological adaptations to using and learning speech evolve, even though the system of speech sounds itself changes at a more rapid time scale than biological evolution. However, the fact that the available acoustic space is used maximally (a self-organized result of cultural evolution) is constant, and therefore biological evolution does have a stable target. This work shows that when cultural and biological traits are continuous, their co-evolution may lead to cognitive adaptations that are strong enough to detect empirically.

  17. On the biology and evolution of fungi from soda soils

    NARCIS (Netherlands)

    Grum-Grzhimaylo, A.

    2015-01-01

    Summary to the thesis “On the biology and evolution of fungi from soda soils” Alexey Grum-Grzhimaylo The presented thesis addresses aspects of biology and evolution of fungi that were recovered from saline soda soils. The work highlights the fact that saline soda soils are populated by a

  18. Interactions between cultural, social and biological explanations for language evolution.

    Science.gov (United States)

    Steels, Luc

    2012-03-01

    This is a reply to commentaries on a target article in this volume reviewing models for the cultural evolution of language. Many commentaries amplify positions taken in this article but they also cover novel issues in social evolution and biological evolution, which are briefly addressed here.

  19. Biology teachers' attitudes toward and use of Indiana's evolution standards

    Science.gov (United States)

    Donnelly, Lisa A.; Boone, William J.

    2007-02-01

    This study examines the relationship between biology teachers' evolution teaching practices and their regard and use of Indiana state evolution standards. A survey developed by the authors contained five subscales: use of standards; attitude toward standards; attitude toward evolution standards; evolution teaching practices; and demographic information. This survey was administered to 229 Indiana biology teachers. Data were analyzed using the Rasch model to convert Likert rating scale data into ratio data used for parametric analyses. Correlation analysis revealed significant relationships between use of standards and attitude toward standards, attitude toward standards and evolution teaching practices, and attitude toward evolution standards and days teaching evolution. These findings suggest practical relationships between standards use, teachers' regard of standards, and evolution teaching practices.

  20. Mass Extinctions vs. Uniformitarianism in Biological Evolution

    OpenAIRE

    Bak, Per; Paczuski, Maya

    1996-01-01

    It is usually believed that Darwin's theory leads to a smooth gradual evolution, so that mass extinctions must be caused by external shocks. However, it has recently been argued that mass extinctions arise from the intrinsic dynamics of Darwinian evolution. Species become extinct when swept by intermittent avalanches propagating through the global ecology. These ideas are made concrete through studies of simple mathematical models of coevolving species. The models exhibit self-organized criti...

  1. Muslim Egyptian and Lebanese Students' Conceptions of Biological Evolution

    Science.gov (United States)

    BouJaoude, Saouma; Wiles, Jason R.; Asghar, Anila; Alters, Brian

    2011-01-01

    In this study, we investigated distinctions among the diversity of religious traditions represented by Lebanese and Egyptian Muslim high school students regarding their understanding and acceptance of biological evolution and how they relate the science to their religious beliefs. We explored secondary students' conceptions of evolution among…

  2. Entropy, biological evolution and the psychological arrow of time

    CERN Document Server

    Heinrich, Torsten; Päs, Heinrich

    2014-01-01

    We argue that in Universes where future and past differ only by the entropy content a psychological arrow of time pointing in the direction of entropy increase can arise from natural selection in biological evolution. We show that this effect can be demonstrated in very simple toy computer simulations of evolution in an entropy increasing or decreasing environment.

  3. Mass extinctions vs. uniformitarianism in biological evolution

    Energy Technology Data Exchange (ETDEWEB)

    Bak, P.; Paczuski, M.

    1995-12-31

    It is usually believed that Darwin`s theory leads to a smooth gradual evolution, so that mass extinctions must be caused by external shocks. However, it has recently been argued that mass extinctions arise from the intrinsic dynamics of Darwinian evolution. Species become extinct when swept by intermittent avalanches propagating through the global ecology. These ideas are made concrete through studies of simple mathematical models of co-evolving species. The models exhibit self-organized criticality and describe some general features of the extinction pattern in the fossil record.

  4. Selection platforms for directed evolution in synthetic biology.

    Science.gov (United States)

    Tizei, Pedro A G; Csibra, Eszter; Torres, Leticia; Pinheiro, Vitor B

    2016-08-15

    Life on Earth is incredibly diverse. Yet, underneath that diversity, there are a number of constants and highly conserved processes: all life is based on DNA and RNA; the genetic code is universal; biology is limited to a small subset of potential chemistries. A vast amount of knowledge has been accrued through describing and characterizing enzymes, biological processes and organisms. Nevertheless, much remains to be understood about the natural world. One of the goals in Synthetic Biology is to recapitulate biological complexity from simple systems made from biological molecules-gaining a deeper understanding of life in the process. Directed evolution is a powerful tool in Synthetic Biology, able to bypass gaps in knowledge and capable of engineering even the most highly conserved biological processes. It encompasses a range of methodologies to create variation in a population and to select individual variants with the desired function-be it a ligand, enzyme, pathway or even whole organisms. Here, we present some of the basic frameworks that underpin all evolution platforms and review some of the recent contributions from directed evolution to synthetic biology, in particular methods that have been used to engineer the Central Dogma and the genetic code.

  5. Collective evolution of biological and physical systems

    Science.gov (United States)

    Vetsigian, Kalin Horen

    I study the evolution of solidification fronts propagating in undercooled liquids, the evolution of microbial communities through diversification fronts propagating along microbial genomes, the evolution of the universality and optimality of the genetic code, and the emergence of genome biases. I present a phase-field model of solidification which allows efficient computations in the regime when interface kinetic effects dominate over capillary effects. I model the competition between homologous recombination and point mutation in microbial genomes, and present evidence for two distinct phases, one uniform and the other genetically diverse. I find that global sequence divergence can be mediated by fronts propagating along the genome, whose characteristic signature is elucidated, and apparently observed in closely related genomes from the Bacillus cereus group. Front propagation provides an emergent, generic mechanism for microbial "speciation," and suggests a classification of microorganisms on the basis of their propensity to support propagating fronts. I propose that selection on the speed, accuracy and energy efficiency of template-directed synthesis processes, such as translation, transcription and replication, can lead to the spontaneous emergence of genome biases. Selection on translation leads to codon usage bias; selection on transcription or replication leads to nucleotide composition biases such as the GC content. These biases result from the generic tradeoffs inherent to template-directed synthesis and occur even in the absence of biased mutation or direct selection on the nucleotide composition. Then, I show that the coevolution between tRNA expression levels and codon usage provides an efficient mechanism for optimization of genetic codes, even if, as the frozen accident theory assumes, every amino acid substitution is lethal at least at some genome sites. Finally, I investigate the proposition that genetic exchange dominating the early evolution of

  6. Human evolution. Evolution of early Homo: an integrated biological perspective.

    Science.gov (United States)

    Antón, Susan C; Potts, Richard; Aiello, Leslie C

    2014-07-04

    Integration of evidence over the past decade has revised understandings about the major adaptations underlying the origin and early evolution of the genus Homo. Many features associated with Homo sapiens, including our large linear bodies, elongated hind limbs, large energy-expensive brains, reduced sexual dimorphism, increased carnivory, and unique life history traits, were once thought to have evolved near the origin of the genus in response to heightened aridity and open habitats in Africa. However, recent analyses of fossil, archaeological, and environmental data indicate that such traits did not arise as a single package. Instead, some arose substantially earlier and some later than previously thought. From ~2.5 to 1.5 million years ago, three lineages of early Homo evolved in a context of habitat instability and fragmentation on seasonal, intergenerational, and evolutionary time scales. These contexts gave a selective advantage to traits, such as dietary flexibility and larger body size, that facilitated survival in shifting environments.

  7. Time rescaling and pattern formation in biological evolution.

    Science.gov (United States)

    Igamberdiev, Abir U

    2014-09-01

    Biological evolution is analyzed as a process of continuous measurement in which biosystems interpret themselves in the environment resulting in changes of both. This leads to rescaling of internal time (heterochrony) followed by spatial reconstructions of morphology (heterotopy). The logical precondition of evolution is the incompleteness of biosystem's internal description, while the physical precondition is the uncertainty of quantum measurement. The process of evolution is based on perpetual changes in interpretation of information in the changing world. In this interpretation the external biospheric gradients are used for establishment of new features of organization. It is concluded that biological evolution involves the anticipatory epigenetic changes in the interpretation of genetic symbolism which cannot generally be forecasted but can provide canalization of structural transformations defined by the existing organization and leading to predictable patterns of form generation.

  8. Review, Intelligence and Development of Rare Earths during Biological Evolution

    Institute of Scientific and Technical Information of China (English)

    Qiu Guanming; Li Wei; Zhang Ming; Li Zhe; Yan Changhao; Li Yourong; Ding Guohui

    2004-01-01

    The relationship between organism and rare earth elements (REE) viewed from evolution was discussed.Some metal ions play key roles in biological functions, however, as the illustration in this article shows, with powerful affinities for oxygen and similar radius, REE can display equally or even more important functions in terms of its biological functions. These attractive characteristics have called more public attention and lead to many applications in agriculture, medicine fields, etc. Furthermore, the article employed the concept of entropy to discuss the dosage effect of REE on organism and the possibility whether REE can become a portion of organism during the evolution.

  9. In search of biology. Reflections on evolution

    Directory of Open Access Journals (Sweden)

    Sandín, Máximo

    2009-12-01

    Full Text Available After 150 years conceiving and dealing with Nature in terms of competence, costs-benefits, exploitation of resources, strategies…, we have managed to make it enter into a «recession». This estrangement from reality and from natural phenomena, has seriously jeopardized the future of mankind on our planet and makes it necessary, even urgent, the search for a conception of biology based on scientific concepts and vocabulary that re-connects us with Nature before it is too late.

    Después de 150 años de concebir y tratar a la Naturaleza en términos de competencia, costebeneficio, explotación de recursos, estrategias…, hemos conseguido que ésta entre en «recesión». Este alejamiento de la realidad, de los fenómenos naturales, ha puesto en grave peligro el futuro de la Humanidad sobre nuestro planeta y hace necesaria, incluso urgente, la búsqueda de una concepción de la Biología basada en conceptos y vocabulario científicos que nos vuelva a conectar con la Naturaleza antes de que sea demasiado tarde.

  10. Quantum information and the problem of mechanisms of biological evolution.

    Science.gov (United States)

    Melkikh, Alexey V

    2014-01-01

    One of the most important conditions for replication in early evolution is the de facto elimination of the conformational degrees of freedom of the replicators, the mechanisms of which remain unclear. In addition, realistic evolutionary timescales can be established based only on partially directed evolution, further complicating this issue. A division of the various evolutionary theories into two classes has been proposed based on the presence or absence of a priori information about the evolving system. A priori information plays a key role in solving problems in evolution. Here, a model of partially directed evolution, based on the learning automata theory, which includes a priori information about the fitness space, is proposed. A potential repository of such prior information is the states of biologically important molecules. Thus, the need for extended evolutionary synthesis is discussed. Experiments to test the hypothesis of partially directed evolution are proposed.

  11. The modern theory of biological evolution: an expanded synthesis

    Science.gov (United States)

    Kutschera, Ulrich; Niklas, Karl J.

    In 1858, two naturalists, Charles Darwin and Alfred Russel Wallace, independently proposed natural selection as the basic mechanism responsible for the origin of new phenotypic variants and, ultimately, new species. A large body of evidence for this hypothesis was published in Darwin's Origin of Species one year later, the appearance of which provoked other leading scientists like August Weismann to adopt and amplify Darwin's perspective. Weismann's neo-Darwinian theory of evolution was further elaborated, most notably in a series of books by Theodosius Dobzhansky, Ernst Mayr, Julian Huxley and others. In this article we first summarize the history of life on Earth and provide recent evidence demonstrating that Darwin's dilemma (the apparent missing Precambrian record of life) has been resolved. Next, the historical development and structure of the ``modern synthesis'' is described within the context of the following topics: paleobiology and rates of evolution, mass extinctions and species selection, macroevolution and punctuated equilibrium, sexual reproduction and recombination, sexual selection and altruism, endosymbiosis and eukaryotic cell evolution, evolutionary developmental biology, phenotypic plasticity, epigenetic inheritance and molecular evolution, experimental bacterial evolution, and computer simulations (in silico evolution of digital organisms). In addition, we discuss the expansion of the modern synthesis, embracing all branches of scientific disciplines. It is concluded that the basic tenets of the synthetic theory have survived, but in modified form. These sub-theories require continued elaboration, particularly in light of molecular biology, to answer open-ended questions concerning the mechanisms of evolution in all five kingdoms of life.

  12. The modern theory of biological evolution: an expanded synthesis.

    Science.gov (United States)

    Kutschera, Ulrich; Niklas, Karl J

    2004-06-01

    In 1858, two naturalists, Charles Darwin and Alfred Russel Wallace, independently proposed natural selection as the basic mechanism responsible for the origin of new phenotypic variants and, ultimately, new species. A large body of evidence for this hypothesis was published in Darwin's Origin of Species one year later, the appearance of which provoked other leading scientists like August Weismann to adopt and amplify Darwin's perspective. Weismann's neo-Darwinian theory of evolution was further elaborated, most notably in a series of books by Theodosius Dobzhansky, Ernst Mayr, Julian Huxley and others. In this article we first summarize the history of life on Earth and provide recent evidence demonstrating that Darwin's dilemma (the apparent missing Precambrian record of life) has been resolved. Next, the historical development and structure of the "modern synthesis" is described within the context of the following topics: paleobiology and rates of evolution, mass extinctions and species selection, macroevolution and punctuated equilibrium, sexual reproduction and recombination, sexual selection and altruism, endosymbiosis and eukaryotic cell evolution, evolutionary developmental biology, phenotypic plasticity, epigenetic inheritance and molecular evolution, experimental bacterial evolution, and computer simulations (in silico evolution of digital organisms). In addition, we discuss the expansion of the modern synthesis, embracing all branches of scientific disciplines. It is concluded that the basic tenets of the synthetic theory have survived, but in modified form. These sub-theories require continued elaboration, particularly in light of molecular biology, to answer open-ended questions concerning the mechanisms of evolution in all five kingdoms of life.

  13. [Neurophysins of Mammals: evolution and biological signification].

    Science.gov (United States)

    Chauvet, M T; Coffe, G; Chauvet, J; Acher, R

    1976-01-01

    Neurohypophysial hormone-Neurophysin complexes have been prepared from posterior pituitary glands of Artiodactyla (ox, sheep, pig), Perissodactyla (horse) and Cetacea (whale), by fractionated salt precipitation. The components have been separated by molecular sieving in 0.2 M acetic acid and neurophysins have been purified by ion-exchange chromatography on DEAE-Sephadex A-50. Two types of neurophysins, MSEL-neurophysins and VLDV-neurophysins, can be distinguished according to the amino acid residues in positions 2, 3, 6 and 7. MSEL-neurophysins of sheep, ox and pig have been characterized by the amino acid sequence. Ovine and bovine MSEL-neurophysins are nearly identical (one substitution out of 95 residues) and porcine MSEL-neurophysin is very similar (four substitutions and an apparent 3-residue C-terminal deletion). The biological function of neurophysins might be the carriage of neurohypophysial hormones but in this respect, each type of neurophysin is not clearly specific for a given hormone. On the other hand, each neurophysin might share a common precursor with a neurohypophysial hormone, the two parts remaining associated after cleavage. However, in the sheep posterior pituitary gland, the molar proportions of the two types of neurophysins, oxytocin and arginine vasopressin, are not equal, MSEL-neurophysin being more abundant than the other components. If a common precursor exists, neurophysins and neurohypophysial hormones are not merely produced by a simple cleavage mechanism.

  14. Restrictions on biological adaptation in language evolution.

    Science.gov (United States)

    Chater, Nick; Reali, Florencia; Christiansen, Morten H

    2009-01-27

    Language acquisition and processing are governed by genetic constraints. A crucial unresolved question is how far these genetic constraints have coevolved with language, perhaps resulting in a highly specialized and species-specific language "module," and how much language acquisition and processing redeploy preexisting cognitive machinery. In the present work, we explored the circumstances under which genes encoding language-specific properties could have coevolved with language itself. We present a theoretical model, implemented in computer simulations, of key aspects of the interaction of genes and language. Our results show that genes for language could have coevolved only with highly stable aspects of the linguistic environment; a rapidly changing linguistic environment does not provide a stable target for natural selection. Thus, a biological endowment could not coevolve with properties of language that began as learned cultural conventions, because cultural conventions change much more rapidly than genes. We argue that this rules out the possibility that arbitrary properties of language, including abstract syntactic principles governing phrase structure, case marking, and agreement, have been built into a "language module" by natural selection. The genetic basis of human language acquisition and processing did not coevolve with language, but primarily predates the emergence of language. As suggested by Darwin, the fit between language and its underlying mechanisms arose because language has evolved to fit the human brain, rather than the reverse.

  15. Corrections to chance fluctuations: quantum mind in biological evolution?

    Science.gov (United States)

    Damiani, Giuseppe

    2009-01-01

    According to neo-Darwinian theory, biological evolution is produced by natural selection of random hereditary variations. This assumption stems from the idea of a mechanical and deterministic world based on the laws of classic physics. However, the increased knowledge of relationships between metabolism, epigenetic systems, and editing of nucleic acids suggests the existence of self-organized processes of adaptive evolution in response to environmental stresses. Living organisms are open thermodynamic systems which use entropic decay of external source of electromagnetic energy to increase their internal dynamic order and to generate new genetic and epigenetic information with a high degree of coherency and teleonomic creativity. Sensing, information processing, and decision making of biological systems might be mainly quantum phenomena. Amplification of microscopic quantum events using the long-range correlation of fractal structures, at the borderline between deterministic order and unpredictable chaos, may be used to direct a reproducible transition of the biological systems towards a defined macroscopic state. The discoveries of many natural genetic engineering systems, the ability to choose the most effective solutions, and the emergence of complex forms of consciousness at different levels confirm the importance of mind-action directed processes in biological evolution, as suggested by Alfred Russel Wallace. Although the main Darwinian principles will remain a crucial component of our understanding of evolution, a radical rethinking of the conceptual structure of the neo-Darwinian theory is needed.

  16. The Effectiveness of an Online Curriculum on High School Students' Understanding of Biological Evolution

    Science.gov (United States)

    Marsteller, Robert B.; Bodzin, Alec M.

    2015-01-01

    An online curriculum about biological evolution was designed to promote increased student content knowledge and evidentiary reasoning. A feasibility study was conducted with 77 rural high school biology students who learned with the online biological evolution unit. Data sources included the Biological Evolution Assessment Measure (BEAM), an…

  17. Factors Potentially Influencing Student Acceptance of Biological Evolution

    Science.gov (United States)

    Wiles, Jason R.

    This investigation explored scientific, religious, and otherwise nonscientific factors that may influence student acceptance of biological evolution and related concepts, how students perceived these factors to have influenced their levels of acceptance of evolution and changes therein, and what patterns arose among students' articulations of how their levels of acceptance of evolution may have changed. This exploration also measured the extent to which students' levels of acceptance changed following a treatment designed to address factors identified as potentially affecting student acceptance of evolution. Acceptance of evolution was measured using the MATE instrument (Rutledge and Warden, 1999; Rutledge and Sadler, 2007) among participants enrolled in a secondary-level academic program during the summer prior to their final year of high school and as they transitioned to the post-secondary level. Student acceptance of evolution was measured to be significantly higher than pre-treatment levels both immediately following and slightly over one year after treatment. Qualitative data from informal questionnaires, from formal course evaluations, and from semi-structured interviews of students engaged in secondary level education and former students at various stages of post-secondary education confirmed that the suspected factors were perceived by participants to have influenced their levels of acceptance of evolution. Furthermore, participant reports provided insight regarding the relative effects they perceived these factors to have had on their evolution acceptance levels. Additionally, many participants reported that their science teachers in public schools had avoided, omitted, or denigrated evolution during instruction, and several of these students expressed frustration regarding what they perceived to have been a lack of education of an important scientific principle. Finally, no students expressed feelings of being offended by having been taught about

  18. Rapid biological speciation driven by tectonic evolution in New Zealand

    Science.gov (United States)

    Craw, Dave; Upton, Phaedra; Burridge, Christopher P.; Wallis, Graham P.; Waters, Jonathan M.

    2016-02-01

    Collisions between tectonic plates lead to the rise of new mountain ranges that can separate biological populations and ultimately result in new species. However, the identification of links between tectonic mountain-building and biological speciation is confounded by environmental and ecological factors. Thus, there are surprisingly few well-documented examples of direct tectonic controls on terrestrial biological speciation. Here we present examples from New Zealand, where the rapid evolution of 18 species of freshwater fishes has resulted from parallel tectonic landscape evolution. We use numerical models to reconstruct changes in the deep crustal structure and surface drainage catchments of the southern island of New Zealand over the past 25 million years. We show that the island and mountain topography evolved in six principal tectonic zones, which have distinct drainage catchments that separated fish populations. We use new and existing phylogenetic analyses of freshwater fish populations, based on over 1,000 specimens from more than 400 localities, to show that fish genomes can retain evidence of this tectonic landscape development, with a clear correlation between geologic age and extent of DNA sequence divergence. We conclude that landscape evolution has controlled on-going biological diversification over the past 25 million years.

  19. REVIEWS OF TOPICAL PROBLEMS: The essence of biological evolution

    Science.gov (United States)

    Vol'kenshteĭn, M. V.

    1984-07-01

    The current state of the theory of biological evolution is reviewed. Evolution is compared with the cosmological processes of structure formation. Both occur in dissipative systems and are governed by export of entropy. The objections to Darwin's theory are discussed and rejected. A sufficient material for evolution is indicated, as determined by the vast supply of variability of organisms. The reasons for this variability are described. The problems of speciation are discussed and its similarity to phase transitions is demonstrated. The phenomena of punctuated equilibrium and phyletic gradualism are described and examples of both are given. Special attention is paid to directional evolution. The views of L.S. Berg are examined in detail. Directionality is governed by natural selection, and also by the type of organism that has evolved and its possible variations. The link between individual and evolutionary development is studied. Wolpert's theory of positional information is presented and the concept of the model theory of morphogenesis is outlined. It is shown that a number of traits of organisms may have no adaptive value. The evolution of the visual organ is described. The molecular foundations of evolution and the neutralist theory, according to which the evolution of proteins and nucleic acids occurs to a considerable extent independently of natural selection, are studied in detail. Arguments in favor of this theory are presented and its physical meaning disclosed, which reduces to degeneracy in the correspondence between the primary structure of a protein and its biologic function. The results are presented of current studies that indicate the inconstancy of genomes, with various pathways of altering their structure and regulation. Various aspects of applications of information theory to problems of evolution are examined in detail. The evolutionary significance of the value of information, as defined as its nonredundancy, or irreplaceability, is stressed

  20. Life history evolution and comparative developmental biology of echinoderms.

    Science.gov (United States)

    Hart, Michael W

    2002-01-01

    Evolutionary biologists studying life history variation have used echinoderms in experimental, laboratory, and field studies of life history evolution. This focus on echinoderms grew originally from the tradition of comparative embryology, in which echinoderms were central. The tools for obtaining and manipulating echinoderm gametes and larvae were taken directly from comparative embryological research. In addition, the comparative embryologists employed a diverse array of echinoderms, not a few model species, and this diversity has led to a broad understanding of the development, function, and evolution of echinoderm larvae. As a result, this branch of life history evolution has deep roots in comparative developmental biology of echinoderms. Here two main aspects of this relationship are reviewed. The first is a broad range of studies of fertilization biology, dispersal, population genetics, functional morphology, and asexual reproduction in which developmental biologists might take a keen interest because of the historical origins of this research in echinoderm comparative embryology. The second is a similarly broad variety of topics in life history research in which evolutionary biologists require techniques or data from developmental biology in order to make progress on understanding patterns of life history variation among echinoderm species and higher taxa. Both sets of topics provide opportunities for interaction and collaboration.

  1. On the Conflicts Between Biological and Social Evolution and Between Psychology and Moral Tradition

    Science.gov (United States)

    Campbell, Donald T.

    1975-01-01

    Argues that human urban social complexity has been made possible by social evolution rather than biological evolution, and that this social evolution has had to counter individual selfish tendencies which biological evolution has continued to select as a result of the genetic competition among the cooperators. (Author/JM)

  2. Evolutionary Developmental Biology and Human Language Evolution: Constraints on Adaptation.

    Science.gov (United States)

    Fitch, W Tecumseh

    2012-12-01

    A tension has long existed between those biologists who emphasize the importance of adaptation by natural selection and those who highlight the role of phylogenetic and developmental constraints on organismal form and function. This contrast has been particularly noticeable in recent debates concerning the evolution of human language. Darwin himself acknowledged the existence and importance of both of these, and a long line of biologists have followed him in seeing, in the concept of "descent with modification", a framework naturally able to incorporate both adaptation and constraint. Today, the integrated perspective of modern evolutionary developmental biology ("evo-devo") allows a more subtle and pluralistic approach to these traditional questions, and has provided several examples where the traditional notion of "constraint" can be cashed out in specific, mechanistic terms. This integrated viewpoint is particularly relevant to the evolution of the multiple mechanisms underlying human language, because of the short time available for novel aspects of these mechanisms to evolve and be optimized. Comparative data indicate that many cognitive aspects of human language predate humans, suggesting that pre-adaptation and exaptation have played important roles in language evolution. Thus, substantial components of what many linguists call "Universal Grammar" predate language itself. However, at least some of these older mechanisms have been combined in ways that generate true novelty. I suggest that we can insightfully exploit major steps forward in our understanding of evolution and development, to gain a richer understanding of the principles that underlie human language evolution.

  3. Teaching biological evolution - internal and external evaluation of learning outcomes

    Directory of Open Access Journals (Sweden)

    Clas Olander

    2012-06-01

    Full Text Available This paper reports from a study where teachers and researchers collaborate on designing and validatingtopic-oriented teaching-learning sequences. In an iterative process, data about learning andteaching biological evolution are generated through continuous cycles of design, teaching, evaluation,and redesign. The study involved 180 Swedish students aged 11 – 16, and the overall learning aim was that the students should be able to use the theory of evolution as a tool when explaining the development of life on earth. The aim of this paper is to validate the students’ learning outcome, estimated as appropriation of scientific ways of reasoning in written answers. The students’ answers of questions are analysed before and after interventions (internal evaluation, and compared with the answers from a national sample (external evaluation. The students in the experimental group did develop their reasoning, and they attained the aim, to a greater extent than a national sample.

  4. Biological evolution and Brazilian students: knowledge and acceptance

    Directory of Open Access Journals (Sweden)

    Graciela da Silva Oliveira

    2015-08-01

    Full Text Available The aim of this study was to verify topics of the biological evolution theory Brazilian students affirm to know and their relation with variables such as sex, age, geographical localization, socioeconomical aspects, religion and science. 2.404 high school students (55.1% girls enrolled in 78 Brazilian schools took part of the research. The data was generated through a questionnaire and analyzed using the software Statistical Package for Social Science (SPSS version 18.0. The results point out that the knowledge of topics about evolution is low among students and influenced by the variables tested, the associations identified happened in a diversified way, and in lower or higher intensity according to the context studied.

  5. Approach of Complex-Systems Biology to Reproduction and Evolution

    Science.gov (United States)

    Kaneko, Kunihiko

    Two basic issues in biology - the origin of life and evolution of phenotypes - are discussed on the basis of statistical physics and dynamical systems. In section "A Bridge Between Catalytic Reaction Networks and Reproducing Cells", we survey recent developments in the origin of reproducing cells from an ensemble of catalytic reactions. After surveying several models of catalytic reaction networks briefly, we provide possible answers to the following three questions: (1) How are nonequilibrium states sustained in catalytic reaction dynamics? (2) How is recursive production of a cell maintaining composition of a variety of chemicals possible? (3) How does a specific molecule species carry information for heredity? In section "Evolution", general relationships between plasticity, robustness, and evolvability are presented in terms of phenotypic fluctuations. First, proportionality between evolution speed, phenotypic plasticity, and isogenic phenotypic fluctuation is proposed by extending the fluctuation-response relationship in physics. We then derive a general proportionality relationship between the phenotypic fluctuations of epigenetic and genetic origin: the former is the variance of phenotype due to noise in the developmental process, and the latter due to genetic mutation. The relationship also suggests a link between robustness to noise and to mutation. These relationships are confirmed in models of gene expression dynamics, as well as in laboratory experiments, and then are explained by a theory based on an evolutionary stability hypothesis For both sections "A Bridge Between Catalytic Reaction Networks and Reproducing Cells" and "Evolution", consistency between two levels of hierarchy (i.e., molecular and cellular, or genetic and phenotypic levels) is stressed as a principle for complex-systems biology.

  6. The Evolution of Biological Complexity in Digital Organisms

    Science.gov (United States)

    Ofria, Charles

    2013-03-01

    When Darwin first proposed his theory of evolution by natural selection, he realized that it had a problem explaining the origins of traits of ``extreme perfection and complication'' such as the vertebrate eye. Critics of Darwin's theory have latched onto this perceived flaw as a proof that Darwinian evolution is impossible. In anticipation of this issue, Darwin described the perfect data needed to understand this process, but lamented that such data are ``scarcely ever possible'' to obtain. In this talk, I will discuss research where we use populations of digital organisms (self-replicating and evolving computer programs) to elucidate the genetic and evolutionary processes by which new, highly-complex traits arise, drawing inspiration directly from Darwin's wistful thinking and hypotheses. During the process of evolution in these fully-transparent computational environments we can measure the incorporation of new information into the genome, a process akin to a natural Maxwell's Demon, and identify the original source of any such information. We show that, as Darwin predicted, much of the information used to encode a complex trait was already in the genome as part of simpler evolved traits, and that many routes must be possible for a new complex trait to have a high probability of successfully evolving. In even more extreme examples of the evolution of complexity, we are now using these same principles to examine the evolutionary dynamics the drive major transitions in evolution; that is transitions to higher-levels of organization, which are some of the most complex evolutionary events to occur in nature. Finally, I will explore some of the implications of this research to other aspects of evolutionary biology and as well as ways that these evolutionary principles can be applied toward solving computational and engineering problems.

  7. Without it no music: cognition, biology and evolution of musicality.

    Science.gov (United States)

    Honing, Henkjan; ten Cate, Carel; Peretz, Isabelle; Trehub, Sandra E

    2015-03-19

    Musicality can be defined as a natural, spontaneously developing trait based on and constrained by biology and cognition. Music, by contrast, can be defined as a social and cultural construct based on that very musicality. One critical challenge is to delineate the constituent elements of musicality. What biological and cognitive mechanisms are essential for perceiving, appreciating and making music? Progress in understanding the evolution of music cognition depends upon adequate characterization of the constituent mechanisms of musicality and the extent to which they are present in non-human species. We argue for the importance of identifying these mechanisms and delineating their functions and developmental course, as well as suggesting effective means of studying them in human and non-human animals. It is virtually impossible to underpin the evolutionary role of musicality as a whole, but a multicomponent perspective on musicality that emphasizes its constituent capacities, development and neural cognitive specificity is an excellent starting point for a research programme aimed at illuminating the origins and evolution of musical behaviour as an autonomous trait.

  8. Biological evolution of replicator systems: towards a quantitative approach.

    Science.gov (United States)

    Martin, Osmel; Horvath, J E

    2013-04-01

    The aim of this work is to study the features of a simple replicator chemical model of the relation between kinetic stability and entropy production under the action of external perturbations. We quantitatively explore the different paths leading to evolution in a toy model where two independent replicators compete for the same substrate. To do that, the same scenario described originally by Pross (J Phys Org Chem 17:312-316, 2004) is revised and new criteria to define the kinetic stability are proposed. Our results suggest that fast replicator populations are continually favored by the effects of strong stochastic environmental fluctuations capable to determine the global population, the former assumed to be the only acting evolution force. We demonstrate that the process is continually driven by strong perturbations only, and that population crashes may be useful proxies for these catastrophic environmental fluctuations. As expected, such behavior is particularly enhanced under very large scale perturbations, suggesting a likely dynamical footprint in the recovery patterns of new species after mass extinction events in the Earth's geological past. Furthermore, the hypothesis that natural selection always favors the faster processes may give theoretical support to different studies that claim the applicability of maximum principles like the Maximum Metabolic Flux (MMF) or Maximum Entropy Productions Principle (MEPP), seen as the main goal of biological evolution.

  9. Methods of information geometry in computational system biology (consistency between chemical and biological evolution).

    Science.gov (United States)

    Astakhov, Vadim

    2009-01-01

    Interest in simulation of large-scale metabolic networks, species development, and genesis of various diseases requires new simulation techniques to accommodate the high complexity of realistic biological networks. Information geometry and topological formalisms are proposed to analyze information processes. We analyze the complexity of large-scale biological networks as well as transition of the system functionality due to modification in the system architecture, system environment, and system components. The dynamic core model is developed. The term dynamic core is used to define a set of causally related network functions. Delocalization of dynamic core model provides a mathematical formalism to analyze migration of specific functions in biosystems which undergo structure transition induced by the environment. The term delocalization is used to describe these processes of migration. We constructed a holographic model with self-poetic dynamic cores which preserves functional properties under those transitions. Topological constraints such as Ricci flow and Pfaff dimension were found for statistical manifolds which represent biological networks. These constraints can provide insight on processes of degeneration and recovery which take place in large-scale networks. We would like to suggest that therapies which are able to effectively implement estimated constraints, will successfully adjust biological systems and recover altered functionality. Also, we mathematically formulate the hypothesis that there is a direct consistency between biological and chemical evolution. Any set of causal relations within a biological network has its dual reimplementation in the chemistry of the system environment.

  10. Quantum selfish gene (biological evolution in terms of quantum mechanics)

    CERN Document Server

    Ozhigov, Yuri I

    2014-01-01

    I propose to treat the biological evolution of genoms by means of quantum mechanical tools. We start with the concept of meta- gene, which specifies the "selfish gene" of R.Dawkins. Meta- gene encodes the abstract living unity, which can live relatively independently of the others, and can contain a few real creatures. Each population of living creatures we treat as the wave function on meta- genes, which module squared is the total number of creatures with the given meta-gene, and the phase is the sum of "aspirations" to change the classical states of meta- genes. Each individual life thus becomes one of possible outcomes of the virtual quantum measurement of this function. The evolution of genomes is described by the unitary operator in the space of psi-functions or by Kossovsky-Lindblad equation in the case of open biosystems. This operator contains all the information about specific conditions under which individuals are, and how "aspirations" of their meta- genes may be implemented at the biochemical lev...

  11. The evolution of fairness in a biological market.

    Science.gov (United States)

    André, Jean-Baptiste; Baumard, Nicolas

    2011-05-01

    Human beings universally express a concern for the fairness of social interactions, and it remains an open question that which ultimate factors led to the evolution of this preference. Here, we present a model accounting for the evolution of fairness on the basis of individual selection alone. We consider a simple social interaction based on the Dictator Game. Two individuals, a "proposer" and a "responder," have an opportunity to split a resource. When they have no choice but to interact together, the most powerful (here the proposer) reaps all the profits and fairness cannot evolve. Partner choice is the key lever to overcome this difficulty. Rather than just two individuals, we consider a population composed of two classes of individuals (either proposers or responders), and we allow the responders to choose their partner. In such a "biological market," fairness evolves as an "equilibrium price," resulting from an ecological equivalent of the law of supply and demand. If a class is disadvantaged by the chosen resource partition (i.e., if it frequently receives less than half of the resource), it is outcompeted by the other one, and automatically becomes rarer. This rarity grants it an advantage on the market, which yields in turn to the evolution of a more favorable partition. Splitting the resource into two identical halves, or more generally in a way that equalizes the payoffs of the two classes, is then the only evolutionarily stable outcome. Beyond human fairness, this mechanism also opens up new ways of explaining the distribution of benefits in many mutualistic interactions.

  12. The evolution of floral biology in basal angiosperms.

    Science.gov (United States)

    Endress, Peter K

    2010-02-12

    In basal angiosperms (including ANITA grade, magnoliids, Choranthaceae, Ceratophyllaceae) almost all bisexual flowers are dichogamous (with male and female functions more or less separated in time), and nearly 100 per cent of those are protogynous (with female function before male function). Movements of floral parts and differential early abscission of stamens in the male phase are variously associated with protogyny. Evolution of synchronous dichogamy based on the day/night rhythm and anthesis lasting 2 days is common. In a few clades in Magnoliales and Laurales heterodichogamy has also evolved. Beetles, flies and thrips are the major pollinators, with various degrees of specialization up to large beetles and special flies in some large-flowered Nymphaeaceae, Magnoliaceae, Annonaceae and Aristolochiaceae. Unusual structural specializations are involved in floral biological adaptations (calyptras, inner staminodes, synandria and food bodies, and secretory structures on tepals, stamens and staminodes). Numerous specializations that are common in monocots and eudicots are absent in basal angiosperms. Several families are poorly known in their floral biology.

  13. Evolution of bow-tie architectures in biology.

    Directory of Open Access Journals (Sweden)

    Tamar Friedlander

    2015-03-01

    Full Text Available Bow-tie or hourglass structure is a common architectural feature found in many biological systems. A bow-tie in a multi-layered structure occurs when intermediate layers have much fewer components than the input and output layers. Examples include metabolism where a handful of building blocks mediate between multiple input nutrients and multiple output biomass components, and signaling networks where information from numerous receptor types passes through a small set of signaling pathways to regulate multiple output genes. Little is known, however, about how bow-tie architectures evolve. Here, we address the evolution of bow-tie architectures using simulations of multi-layered systems evolving to fulfill a given input-output goal. We find that bow-ties spontaneously evolve when the information in the evolutionary goal can be compressed. Mathematically speaking, bow-ties evolve when the rank of the input-output matrix describing the evolutionary goal is deficient. The maximal compression possible (the rank of the goal determines the size of the narrowest part of the network-that is the bow-tie. A further requirement is that a process is active to reduce the number of links in the network, such as product-rule mutations, otherwise a non-bow-tie solution is found in the evolutionary simulations. This offers a mechanism to understand a common architectural principle of biological systems, and a way to quantitate the effective rank of the goals under which they evolved.

  14. The emergence and early evolution of biological carbon-fixation.

    Directory of Open Access Journals (Sweden)

    Rogier Braakman

    Full Text Available The fixation of CO₂ into living matter sustains all life on Earth, and embeds the biosphere within geochemistry. The six known chemical pathways used by extant organisms for this function are recognized to have overlaps, but their evolution is incompletely understood. Here we reconstruct the complete early evolutionary history of biological carbon-fixation, relating all modern pathways to a single ancestral form. We find that innovations in carbon-fixation were the foundation for most major early divergences in the tree of life. These findings are based on a novel method that fully integrates metabolic and phylogenetic constraints. Comparing gene-profiles across the metabolic cores of deep-branching organisms and requiring that they are capable of synthesizing all their biomass components leads to the surprising conclusion that the most common form for deep-branching autotrophic carbon-fixation combines two disconnected sub-networks, each supplying carbon to distinct biomass components. One of these is a linear folate-based pathway of CO₂ reduction previously only recognized as a fixation route in the complete Wood-Ljungdahl pathway, but which more generally may exclude the final step of synthesizing acetyl-CoA. Using metabolic constraints we then reconstruct a "phylometabolic" tree with a high degree of parsimony that traces the evolution of complete carbon-fixation pathways, and has a clear structure down to the root. This tree requires few instances of lateral gene transfer or convergence, and instead suggests a simple evolutionary dynamic in which all divergences have primary environmental causes. Energy optimization and oxygen toxicity are the two strongest forces of selection. The root of this tree combines the reductive citric acid cycle and the Wood-Ljungdahl pathway into a single connected network. This linked network lacks the selective optimization of modern fixation pathways but its redundancy leads to a more robust topology

  15. Biology Students' and Teachers' Religious Beliefs and Attitudes towards Theory of Evolution

    Science.gov (United States)

    Ozay Kose, Esra

    2010-01-01

    Evolution has not being well addressed in schools partly because it is a controversial topic in religious views. In the present study, it is explored to what extent Turkish secondary school biology teachers and students accommodate the theory of biological evolution with their religious beliefs. Two-hundred fifty secondary school students and…

  16. Taiwan High School Biology Teachers' Acceptance and Understanding of Evolution and the Nature of Science

    Science.gov (United States)

    Chen, Li-Hua

    2015-01-01

    Evolution is the cornerstone of biological sciences, but anti-evolution teaching has become a global controversy since the introduction of evolutionary ideas into the United States high school science curricula in 1914. It is suggested that teachers' attitude toward and acceptance of the theory of evolution will influence their effect of teaching…

  17. Conceptual change about evolution and origins of life throughout an undergraduate course of biological sciences

    OpenAIRE

    2014-01-01

    This research aimed to understand how students at different terms of a Biological Sciences course deal with the themes of evolution and the origin of life. The research instrument was a questionnaire developed within the European project BIOHEAD-CITIZEN applied in several countries aiming at analysing the views of students and teachers about health, environment and evolution. For this study only evolution questions were selected, which were answered by 56 students of the course of Biological ...

  18. [Thermodynamic theory of biological evolution and aging. Experimental verification of the theory].

    Science.gov (United States)

    Gladyshev, G P

    2000-01-01

    Experimental data confirming original thermodynamic theory of biological evolution and aging are presented. Biological evolution (phylogenesis) and ontogenesis can be easily described within the frames of equilibrium hierarchical thermodynamics on the basis of temporal hierarchies law and the second principle of thermodynamics. The theory explains many facts and suggests new practical proposals in medical and biological science, particularly, in dietology, gerontology, and geriatrics. Application of the temporal hierarchies model to studying living nature offers horizonless possibilities for its understanding.

  19. Learning bias, cultural evolution of language, and the biological evolution of the language faculty.

    Science.gov (United States)

    Smith, Kenny

    2011-04-01

    The biases of individual language learners act to determine the learnability and cultural stability of languages: learners come to the language learning task with biases which make certain linguistic systems easier to acquire than others. These biases are repeatedly applied during the process of language transmission, and consequently should effect the types of languages we see in human populations. Understanding the cultural evolutionary consequences of particular learning biases is therefore central to understanding the link between language learning in individuals and language universals, common structural properties shared by all the world’s languages. This paper reviews a range of models and experimental studies which show that weak biases in individual learners can have strong effects on the structure of socially learned systems such as language, suggesting that strong universal tendencies in language structure do not require us to postulate strong underlying biases or constraints on language learning. Furthermore, understanding the relationship between learner biases and language design has implications for theories of the evolution of those learning biases: models of gene-culture coevolution suggest that, in situations where a cultural dynamic mediates between properties of individual learners and properties of language in this way, biological evolution is unlikely to lead to the emergence of strong constraints on learning.

  20. Evolution and Personal Religious Belief: Christian University Biology-Related Majors' Search for Reconciliation

    Science.gov (United States)

    Winslow, Mark W.; Staver, John R.; Scharmann, Lawrence C.

    2011-01-01

    The goal of this study was to explore Christian biology-related majors' perceptions of conflicts between evolution and their religious beliefs. This naturalistic study utilized a case study design of 15 undergraduate biology-related majors at or recent biology-related graduates from a mid-western Christian university. The broad sources of data…

  1. Biology, genome organization, and evolution of parvoviruses in marine shrimp.

    Science.gov (United States)

    Dhar, Arun K; Robles-Sikisaka, Refugio; Saksmerprome, Vanvimon; Lakshman, Dilip K

    2014-01-01

    As shrimp aquaculture has evolved from a subsistent farming activity to an economically important global industry, viral diseases have also become a serious threat to the sustainable growth and productivity of this industry. Parvoviruses represent an economically important group of viruses that has greatly affected shrimp aquaculture. In the early 1980s, an outbreak of a shrimp parvovirus, infectious hypodermal and hematopoietic necrosis virus (IHHNV), led to the collapse of penaeid shrimp farming in the Americas. Since then, considerable progress has been made in characterizing the parvoviruses of shrimp and developing diagnostic methods aimed to preventing the spread of diseases caused by these viruses. To date, four parvoviruses are known that infect shrimp; these include IHHNV, hepatopancreatic parvovirus (HPV), spawner-isolated mortality virus (SMV), and lymphoid organ parvo-like virus. Due to the economic repercussions that IHHNV and HPV outbreaks have caused to shrimp farming over the years, studies have been focused mostly on these two pathogens, while information on SMV and LPV remains limited. IHHNV was the first shrimp virus to be sequenced and the first for which highly sensitive diagnostic methods were developed. IHHNV-resistant lines of shrimp were also developed to mitigate the losses caused by this virus. While the losses due to IHHNV have been largely contained in recent years, reports of HPV-induced mortalities in larval stages in hatchery and losses due to reduced growth have increased. This review presents a comprehensive account of the history and current knowledge on the biology, diagnostics methods, genomic features, mechanisms of evolution, and management strategies of shrimp parvoviruses. We also highlighted areas where research efforts should be focused in order to gain further insight on the mechanisms of parvoviral pathogenicity in shrimp that will help to prevent future losses caused by these viruses.

  2. Factors which influence Texas biology teachers' decisions to emphasize fundamental concepts of evolution

    Science.gov (United States)

    Bilica, Kimberly Lynn

    The teaching of biological evolution in public science classrooms has been mitigated by a lingering and historic climate of controversy (Skoog, 1984; Skoog, 1979). This controversy has successfully stalled attempts to bring authentic science literacy to the American public (Bybee, 1997). The first encouraging signs of the abatement of this controversy occurred during the early 1990s when several prominent science organizations promoted evolution to its appropriate status as a central and unifying concept in biology (National Science Teachers Association, 1992; National Research Council, 1996; American Association for the Advancement of Science, 1990, 1993). The organizations acknowledged that not only should biological evolution be taught, evolution should stand as one of a select group of essential concepts upon which biology curricula should be built. Bandura's Social Learning theory (Bandura, 1997; Lumpe, Haney, & Czerniak, 2000) and Helms' Model of Identity (Helms, 1998) provide the theoretical basis for this study. Both Bandura and Helms explain the actions of teachers by examining the beliefs and values that influence their decisions. The models distinguish between two types of belief systems: capacity beliefs and context beliefs (Lumpe, et al, 2000; Helms, 1998). Both belief types influence and are influenced by individual actions. In this study, the action to be described is the decision that teachers make about the degree of emphasis on evolution in the classroom. The capacity beliefs that will be examined are teachers' beliefs about their capability to teach evolution. The contextual beliefs in this study are perceptions about students' capabilities to learn evolution, the status of evolution in science, the place of evolution in the biology classroom, the influence of textbooks, time, and community/school values. This study contributes to and extends the knowledge base established by studies of evolution education by exploring the relative amount of

  3. Evolution Kills: A Web Resource for Instructors of Evolutionary Biology

    Science.gov (United States)

    Vondrasek, Joanna R.; Antonovics, Janis; Taylor, Douglas R.

    2004-01-01

    We have developed a laboratory course that demonstrates how evolution can be taught as a participatory, investigative science at the undergraduate college or advanced secondary high school level. The course emphasizes the applied importance of evolution to areas such as medicine and agriculture. Because many instructors face budgetary or other…

  4. Biology of the sauropod dinosaurs: the evolution of gigantism.

    Science.gov (United States)

    Sander, P Martin; Christian, Andreas; Clauss, Marcus; Fechner, Regina; Gee, Carole T; Griebeler, Eva-Maria; Gunga, Hanns-Christian; Hummel, Jürgen; Mallison, Heinrich; Perry, Steven F; Preuschoft, Holger; Rauhut, Oliver W M; Remes, Kristian; Tütken, Thomas; Wings, Oliver; Witzel, Ulrich

    2011-02-01

    The herbivorous sauropod dinosaurs of the Jurassic and Cretaceous periods were the largest terrestrial animals ever, surpassing the largest herbivorous mammals by an order of magnitude in body mass. Several evolutionary lineages among Sauropoda produced giants with body masses in excess of 50 metric tonnes by conservative estimates. With body mass increase driven by the selective advantages of large body size, animal lineages will increase in body size until they reach the limit determined by the interplay of bauplan, biology, and resource availability. There is no evidence, however, that resource availability and global physicochemical parameters were different enough in the Mesozoic to have led to sauropod gigantism. We review the biology of sauropod dinosaurs in detail and posit that sauropod gigantism was made possible by a specific combination of plesiomorphic characters (phylogenetic heritage) and evolutionary innovations at different levels which triggered a remarkable evolutionary cascade. Of these key innovations, the most important probably was the very long neck, the most conspicuous feature of the sauropod bauplan. Compared to other herbivores, the long neck allowed more efficient food uptake than in other large herbivores by covering a much larger feeding envelope and making food accessible that was out of the reach of other herbivores. Sauropods thus must have been able to take up more energy from their environment than other herbivores. The long neck, in turn, could only evolve because of the small head and the extensive pneumatization of the sauropod axial skeleton, lightening the neck. The small head was possible because food was ingested without mastication. Both mastication and a gastric mill would have limited food uptake rate. Scaling relationships between gastrointestinal tract size and basal metabolic rate (BMR) suggest that sauropods compensated for the lack of particle reduction with long retention times, even at high uptake rates. The

  5. Biology of the sauropod dinosaurs: the evolution of gigantism

    Science.gov (United States)

    Sander, P Martin; Christian, Andreas; Clauss, Marcus; Fechner, Regina; Gee, Carole T; Griebeler, Eva-Maria; Gunga, Hanns-Christian; Hummel, Jürgen; Mallison, Heinrich; Perry, Steven F; Preuschoft, Holger; Rauhut, Oliver W M; Remes, Kristian; Tütken, Thomas; Wings, Oliver; Witzel, Ulrich

    2011-01-01

    The herbivorous sauropod dinosaurs of the Jurassic and Cretaceous periods were the largest terrestrial animals ever, surpassing the largest herbivorous mammals by an order of magnitude in body mass. Several evolutionary lineages among Sauropoda produced giants with body masses in excess of 50 metric tonnes by conservative estimates. With body mass increase driven by the selective advantages of large body size, animal lineages will increase in body size until they reach the limit determined by the interplay of bauplan, biology, and resource availability. There is no evidence, however, that resource availability and global physicochemical parameters were different enough in the Mesozoic to have led to sauropod gigantism. We review the biology of sauropod dinosaurs in detail and posit that sauropod gigantism was made possible by a specific combination of plesiomorphic characters (phylogenetic heritage) and evolutionary innovations at different levels which triggered a remarkable evolutionary cascade. Of these key innovations, the most important probably was the very long neck, the most conspicuous feature of the sauropod bauplan. Compared to other herbivores, the long neck allowed more efficient food uptake than in other large herbivores by covering a much larger feeding envelope and making food accessible that was out of the reach of other herbivores. Sauropods thus must have been able to take up more energy from their environment than other herbivores. The long neck, in turn, could only evolve because of the small head and the extensive pneumatization of the sauropod axial skeleton, lightening the neck. The small head was possible because food was ingested without mastication. Both mastication and a gastric mill would have limited food uptake rate. Scaling relationships between gastrointestinal tract size and basal metabolic rate (BMR) suggest that sauropods compensated for the lack of particle reduction with long retention times, even at high uptake rates. The

  6. Does Life without Past have any Future? The Neglect of Evolution in Synthetic Biology

    Directory of Open Access Journals (Sweden)

    Laura Nuño De La Rosa

    2016-12-01

    Full Text Available Synthetic biology has a singular relation to evolutionary theory. On the one hand, synthetic biology is founded on an engineering interpretation of evolution. On the other hand, bioengineers aspire to free themselves from evolution by building organisms ‘from scratch’ that behave in a predictable way. In this article, I will examine the main properties of the synthetic characterisation of bioartifacts, namely their characterisation as (1 modular and (2 computable systems which are (3 the product of design. I will argue that synthetic biology is founded on a conception of organisms and their relation with their historical legacy which has been deeply challenged by contemporary evolutionary biology.

  7. A Powerful Toolkit for Synthetic Biology: Over 3.8 Billion Years of Evolution

    Science.gov (United States)

    Rothschild, Lynn J.

    2010-01-01

    The combination of evolutionary with engineering principles will enhance synthetic biology. Conversely, synthetic biology has the potential to enrich evolutionary biology by explaining why some adaptive space is empty, on Earth or elsewhere. Synthetic biology, the design and construction of artificial biological systems, substitutes bio-engineering for evolution, which is seen as an obstacle. But because evolution has produced the complexity and diversity of life, it provides a proven toolkit of genetic materials and principles available to synthetic biology. Evolution operates on the population level, with the populations composed of unique individuals that are historical entities. The source of genetic novelty includes mutation, gene regulation, sex, symbiosis, and interspecies gene transfer. At a phenotypic level, variation derives from regulatory control, replication and diversification of components, compartmentalization, sexual selection and speciation, among others. Variation is limited by physical constraints such as diffusion, and chemical constraints such as reaction rates and membrane fluidity. While some of these tools of evolution are currently in use in synthetic biology, all ought to be examined for utility. A hybrid approach of synthetic biology coupled with fine-tuning through evolution is suggested

  8. Discovering local patterns of co - evolution: computational aspects and biological examples

    Directory of Open Access Journals (Sweden)

    Tuller Tamir

    2010-01-01

    Full Text Available Abstract Background Co-evolution is the process in which two (or more sets of orthologs exhibit a similar or correlative pattern of evolution. Co-evolution is a powerful way to learn about the functional interdependencies between sets of genes and cellular functions and to predict physical interactions. More generally, it can be used for answering fundamental questions about the evolution of biological systems. Orthologs that exhibit a strong signal of co-evolution in a certain part of the evolutionary tree may show a mild signal of co-evolution in other branches of the tree. The major reasons for this phenomenon are noise in the biological input, genes that gain or lose functions, and the fact that some measures of co-evolution relate to rare events such as positive selection. Previous publications in the field dealt with the problem of finding sets of genes that co-evolved along an entire underlying phylogenetic tree, without considering the fact that often co-evolution is local. Results In this work, we describe a new set of biological problems that are related to finding patterns of local co-evolution. We discuss their computational complexity and design algorithms for solving them. These algorithms outperform other bi-clustering methods as they are designed specifically for solving the set of problems mentioned above. We use our approach to trace the co-evolution of fungal, eukaryotic, and mammalian genes at high resolution across the different parts of the corresponding phylogenetic trees. Specifically, we discover regions in the fungi tree that are enriched with positive evolution. We show that metabolic genes exhibit a remarkable level of co-evolution and different patterns of co-evolution in various biological datasets. In addition, we find that protein complexes that are related to gene expression exhibit non-homogenous levels of co-evolution across different parts of the fungi evolutionary line. In the case of mammalian evolution

  9. Autocatalysis as the Natural Philosophy Underlying Complexity and Biological Evolution

    Directory of Open Access Journals (Sweden)

    Güngör Gündüz

    2011-06-01

    Full Text Available The importance and different aspects of autocatalysis in evolution was analyzed. The behaviour of autocatalytic reactions mainly the Lotka-Volterra and the Schlögl equations were discussed in terms of phase change, entropy, and their oscillation frequency. The increase of complexity as the general direction of evolution was examined on some patterns in terms of both their entropy and information content. In addition, the relation between stability and functionality, stability and cohesion were discussed. It was concluded that evolution drifts in the direction of increasing complexity as a kind of natural philosophy to counteract the increase of entropy in the universe.

  10. Mathematical modeling of the evolution of a simple biological system

    Digital Repository Service at National Institute of Oceanography (India)

    Gonsalves, M.J.B.D.; Neetu, S.; Krishnan, K.P.; Attri, K.; LokaBharathi, P.A.

    Paula, Goa 403 004, India. Phone: +91 0832 2450624, Fax: +91 0832 2450606, e-mail: mjudith@nio.org Introduction In India, classroom education in biology does not generally include an exercise in which the data can be used to develop models.... This has hampered exposure to quantitative tools in biology, much to the disadvantage of students. The purpose of this note is to report an exercise we carried out to expose traditional biologists educated in India to mathematical modelling of biological...

  11. Mapping biological ideas: Concept maps as knowledge integration tools for evolution education

    OpenAIRE

    Schwendimann, Beat Adrian

    2011-01-01

    Many students leave school with a fragmented understanding of biology that does not allow them to connect their ideas to their everyday lives (Wandersee, 1989; Mintzes, Wandersee, & Novak, 1998; Mintzes, Wandersee, & Novak, 2000a). Understanding evolution ideas is seen as central to building an integrated knowledge of biology (Blackwell, Powell, & Dukes, 2003; Thagard & Findlay, 2010). However, the theory of evolution has been found difficult to understand as it incorporates a wide range of i...

  12. Between creation, evolution and genetic engineering: biology in need of a new bioethics?

    NARCIS (Netherlands)

    Gupta, J.A.

    2009-01-01

    Technological interventions into biological processes through genetic engineering in the twenty-fi rst century could speed up evolution at the velocity of light years in comparison with the millions of years it took for Homo sapiens to reach this stage of evolution until this new millennium. Will th

  13. Science for Survival: The Modern Synthesis of Evolution and the Biological Sciences Curriculum Study

    Science.gov (United States)

    Green, Lisa Anne

    2012-01-01

    In this historical dissertation, I examined the process of curriculum development in the Biological Sciences Curriculum Study (BSCS) in the United States during the period 1959-1963. The presentation of evolution in the high school texts was based on a more robust form of Darwinian evolution which developed during the 1930s and 1940s called…

  14. Evolution in health and medicine Sackler colloquium: 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

    2010-01-26

    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.

  15. The biology of human sexuality: evolution, ecology and physiology

    OpenAIRE

    PW Bateman; NC Bennett

    2006-01-01

    Many evolutionary biologists argue that human sexual behaviour can be studied in exactly the same way as that of other species. Many sociologists argue that social influences effectively obscure, and are more important than, a reductionist biological approach to human sexual behaviour. Here,we authors attempt to provide a broad introduction to human sexual behaviour from a biological standpoint and to indicate where the ambiguous areas are. We outline the evolutionary selective pressures that...

  16. WWW.cell Biology Education: Evolution Web Sites

    Science.gov (United States)

    Liu, Dennis

    2005-01-01

    The debate over teaching evolution has once again reached a fever pitch in the United States. Earnest nineteenth-century clashes between scientific and religious worldviews have given way to the politically charged arguments of creation science and now intelligent design. The Web site of the National Center for Science Education (NCSE;…

  17. Contributions of stochastic events to biological evolution and cancer

    Directory of Open Access Journals (Sweden)

    Anderson KM

    2015-10-01

    Full Text Available Stochastic genetic and epigenetic events have been fundamental in contributing to the development of manifold life-forms, past and present. The development of malignant cell clones and the role of stochasticity as a driving force in cancer cell evolution complements, in a perverse way evidence for the role of chance in normal cellular development and evolution. Stochastic events at multiple levels of cellular control and implementation represent a primary driving force and an ultimate filter through which evolutionary innovation occurs. Stochasticity provides the opportunity for a random assortment of disparate genetic and epigenetic events, in some instances resulting in altered metabolic and developmental capabilities of sufficient stability and uniqueness to contribute to deterministic sequelae that promote the viability and procreation of cells under stress. Cellular evolution has so far resulted in a “survival of a (sic fittest”, often dependent mechanistically on and determined by stochastic events. The implications of this are mirrored in the evolution of malignant change, to some extent as a variant of “reverse engineering” of dedifferentiation. Efforts to reduce the incidence of malignant change will have to take in to account its random nature and further the understanding of this feature.

  18. The Effectiveness of an Online Curriculum on High School Students' Understanding of Biological Evolution

    Science.gov (United States)

    Marsteller, Robert B.; Bodzin, Alec M.

    2015-12-01

    An online curriculum about biological evolution was designed to promote increased student content knowledge and evidentiary reasoning. A feasibility study was conducted with 77 rural high school biology students who learned with the online biological evolution unit. Data sources included the Biological Evolution Assessment Measure (BEAM), an analysis of discussion forum posts, and a post-implementation perceptions and attitudes questionnaire. BEAM posttest scores were significantly higher than the pretest scores. However, the findings revealed that the students required additional support to develop evidentiary reasoning. Many students perceived that the Web-based curriculum would have been enhanced by increased immediate interaction and feedback. Students required greater scaffolding to support complex, process-oriented tasks. Implications for designing Web-based science instruction with curriculum materials to support students' acquisition of content knowledge and science process skills in a Web-based setting are discussed.

  19. A comparison of Massachusetts and Texas high school biology teachers' attitudes towards the teaching of evolution

    Science.gov (United States)

    Howarth, Richard T.

    Darwin's theory of evolution by natural selection is considered to be the unifying theory for all life sciences (American Association for the Advancement of Science, AAAS, 1990; National Academy of Sciences, 1998; National Research Council, NRC, 1996; National Science Teachers Association, NSTA, 2010a) and as such, the biology topic has been established as a central learning standard by the National Science Education Science Standards (NSES, 2005). The purpose of this study was to compare how Massachusetts and Texas high school biology teachers' attitudes toward the teaching of evolution differ as compared to other biology topics. Texas and Massachusetts are two states that exemplify standards based education yet differ dramatically in their histories surrounding the topic of evolution. A survey was conducted among 217 Massachusetts and 139 Texas in-service high school biology teachers to help provide a sense of the phenomena surrounding biology teachers in respect to how their attitudes towards the teaching of evolution are shaped. Additionally, an open-ended question was asked to help contextualize the results of the survey between teachers of these two states. The findings in this study suggest that community appears to be a powerful persuasive message and socialization experience that shapes the development of attitudes towards evolution for some educators, especially when it is highly intertwined with religion. For biology teachers in the state of Texas, the synergistic result of this relationship has resulted in statistically significant differences in regards to attitudes towards evolution as compared to teachers in Massachusetts. These findings yield implications regarding scientific literacy, student learning, assessment, the quality of science instruction, curriculum, undergraduate biology programs, and the needs of biology teachers in terms of professional development.

  20. Women in evolution - highlighting the changing face of evolutionary biology.

    Science.gov (United States)

    Wellenreuther, Maren; Otto, Sarah

    2016-01-01

    The face of science has changed. Women now feature alongside men at the forefront of many fields, and this is particularly true in evolutionary biology. This special issue celebrates the outstanding achievements and contributions of women in evolutionary biology, by highlighting a sample of their research and accomplishments. In addition to original research contributions, this collection of articles contains personal reflections to provide perspective and advice on succeeding as a woman in science. By showcasing the diversity and research excellence of women and drawing on their experiences, we wish to enhance the visibility of female scientists and provide inspiration as well as role models. These are exciting times for evolutionary biology, and the field is richer and stronger for the diversity of voices contributing to the field.

  1. Darwin's legacy: why biology is not physics, or why evolution has not become a common sense.

    Science.gov (United States)

    Singh, Rama S

    2011-10-01

    Cosmology and evolution together have enabled us to look deep into the past and comprehend evolution-from the big bang to the cosmos, from molecules to humans. Here, I compare the nature of theories in biology and physics and ask why physical theories get accepted by the public without necessarily comprehending them but biological theories do not. Darwin's theory of natural selection, utterly simple in its premises but profound in its consequences, is not accepted widely. Organized religions, and creationists in particularly, have been the major critic of evolution, but not all opposition to evolution comes from organized religions. A great many people, between evolutionary biologists on one hand and creationists on the other, many academics included, who may not be logically opposed to evolution nevertheless do not accept it. This is because the process of and the evidence for evolution are invisible to a nonspecialist, or the theory may look too simple to explain complex traits to some, or because people compare evolution against God and find evolutionary explanations threatening to their beliefs. Considering how evolution affects our lives, including health and the environment to give just two examples, a basic course in evolution should become a required component of all our college and university educational systems.

  2. EVOLUTION OF BOTULISM. I. BIOLOGICAL SIGNIFICANCE OF PATHOGENICITY,

    Science.gov (United States)

    nutritional conditions and as a result give rise to the formation of a pathogenic species. The occurrence of this character might have enabled the ancestors of ...sphere of existence. The decomposing carcass of an animal becomes a medium for multiplication and toxin formation and a source for the further... evolution toward the natural selection of forms possessing more pathogenic properties and different methods of adaptation suitable to the new way of life. (Author)

  3. Biology, genome organization and evolution of parvoviruses in marine shrimp

    Science.gov (United States)

    A number of parvoviruses are now know to infect marine shrimp, and these viruses alone or in combination with other viruses have the potential to cause major losses in shrimp aquaculture globally. This review provides a comprehensive overview of the biology, genome organization, gene expression, and...

  4. Without it no music: Cognition, biology, and evolution of musicality

    NARCIS (Netherlands)

    Honing, H.; ten Cate, C.; Peretz, I.; Trehub, S.E.

    2015-01-01

    Musicality can be defined as a natural, spontaneously developing trait based on and constrained by biology and cognition. Music, by contrast, can be defined as a social and cultural construct based on that very musicality. One critical challenge is to delineate the constituent elements of musicality

  5. Optimality in evolution: new insights from synthetic biology.

    Science.gov (United States)

    de Vos, Marjon G J; Poelwijk, Frank J; Tans, Sander J

    2013-08-01

    Whether organisms evolve to perform tasks optimally has intrigued biologists since Lamarck and Darwin. Optimality models have been used to study diverse properties such as shape, locomotion, and behavior. However, without access to the genetic underpinnings or the ability to manipulate biological functions, it has been difficult to understand an organism's intrinsic potential and limitations. Now, novel experiments are overcoming these technical obstacles and have begun to test optimality in more quantitative terms. With the use of simple model systems, genetic engineering, and mathematical modeling, one can independently quantify the prevailing selective pressures and optimal phenotypes. These studies have given an exciting view into the evolutionary potential and constraints of biological systems, and hold the promise to further test the limits of predicting future evolutionary change.

  6. Systematics, evolution, and biology of scelionid and platygastrid wasps.

    Science.gov (United States)

    Austin, A D; Johnson, N F; Dowton, M

    2005-01-01

    The Platygastroidea comprises two families of parasitoids, Scelionidae and Platygastridae, and nearly 4500 described species. They parasitize a diverse array of insects as well as spiders. Idiobiont endoparasitism of eggs is the putative ground plan biology, as reflected by all scelionids, but most Platygastridae are koinobiont endoparasitoids of immature Auchenorrhyncha, Sternorrhyncha, and Cecidomyiidae. The superfamily is demonstrably monophyletic but its phylogenetic position remains uncertain. Relationships within the Platygastroidea are also poorly known and the group is in need of comprehensive phylogenetic study. Significant information is available on host relationships and biology, although much of this is biased to a few genera of Telenominae that are employed as biocontrol agents. Hosts for many genera are unknown, in particular those that inhabit leaf litter or parasitize solitary host eggs. The Trissolcus basalis-Nezara viridula parasitoid-host association has become a favored model system in ecological, behavioral, and physiological research on insects.

  7. The biology of human sexuality: evolution, ecology and physiology

    Directory of Open Access Journals (Sweden)

    PW Bateman

    2006-09-01

    Full Text Available Many evolutionary biologists argue that human sexual behaviour can be studied in exactly the same way as that of other species. Many sociologists argue that social influences effectively obscure, and are more important than, a reductionist biological approach to human sexual behaviour. Here,we authors attempt to provide a broad introduction to human sexual behaviour from a biological standpoint and to indicate where the ambiguous areas are. We outline the evolutionary selective pressures that are likely to have influenced human behaviour and mate choice in the past and in the present; ecological features that influence such things as degree of parental care and polygamy; and the associated physiology of human sexuality. Then they end with a discussion of �abnormal� sexuality.

  8. Synthetic Biology: Engineering, Evolution and Design (SEED) Conference 2014

    Energy Technology Data Exchange (ETDEWEB)

    Voigt, Christopher [Massachusetts Institute of Technology

    2014-07-01

    SEED2014 focused on advances in the science and technology emerging from the field of synthetic biology. We broadly define this as technologies that accelerate the process of genetic engineering. It highlighted new tool development, as well as the application of these tools to diverse problems in biotechnology, including therapeutics, industrial chemicals and fuels, natural products, and agriculture. Systems spanned from in vitro experiments and viruses, through diverse bacteria, to eukaryotes (yeast, mammalian cells, plants).

  9. [Modern evolutional developmental biology: mechanical and molecular genetic or phenotypic approaches?].

    Science.gov (United States)

    Vorob'eva, É I

    2010-01-01

    Heightened interest in the evolutionary problems of developmental biology in the 1980s was due to the success of molecular genetics and disappointment in the synthetic theory of evolution, where the chapters of embryology and developmental biology seem to have been left out. Modern evo-devo, which turned out to be antipodean to the methodology of the synthetic theory of evolution, propagandized in the development of evolutionary problems only the mechanical and molecular genetic approach to the evolution of ontogenesis, based on cellular and intercellular interactions. The phonotypical approach to the evaluation of evolutionary occurrences in ontogenesis, which aids in the joining of the genetic and epigenetic levels of research, the theory of natural selection, the nomogenetic conception, and the problem of the wholeness of the organism in onto- and phylogenesis may be against this. The phenotypic approach to ontogenesis is methodologically the most perspective for evolutionary developmental biology.

  10. The Biological Significance of Evolution in Autoimmune Phenomena

    Directory of Open Access Journals (Sweden)

    Carlos A. Cañas

    2012-01-01

    Full Text Available It is an inherent part of living to be in constant modification, which are due to answers resulting from environmental changes. The different systems make adaptations based on natural selection. With respect to the immune system of mammals, these changes have a lot to do with the interactions that occur continuously with other living species, especially microorganisms. The immune system is primarily designed to defend from germs and this response triggers inflammatory reactions which must be regulated in order not to generate damage to healthy tissue. The regulatory processes were added over time to prevent such damage. Through evolution the species have stored “an immunological experience,” which provides information that is important for developing effective responses in the future. The human species, which is at a high level of evolutionary immunological accumulation, have multiple immune defense strategies which, in turn, are highly regulated. Imbalances in these can result in autoimmunity.

  11. Quantitative Link Between Biological Evolution and Statistical Mechanics

    Science.gov (United States)

    Ray, Tane S.

    A model of evolution called the modified Wright-Fisher model (MWF) is introduced. It is shown to exhibit a second order phase transition, and a quantitative mapping is established between the mean field Ising model and itself. An equation of state and scaling function are derived for the MWF from the steady state solution of the governing quasispecies equations. The critical exponents are identical to those of the mean-field Ising model. Simulation data for the MWF on a two-dimensional square lattice show good evidence for a critical point. The susceptibility exponent is estimated and is found, within the uncertainty of the simulation data, to be equal to that of the two-dimensional Ising model, suggesting that the two models are in the same universality class.

  12. Life’s a Gas: A Thermodynamic Theory of Biological Evolution

    OpenAIRE

    2015-01-01

    This paper outlines a thermodynamic theory of biological evolution. Beginning with a brief summary of the parallel histories of the modern evolutionary synthesis and thermodynamics, we use four physical laws and processes (the first and second laws of thermodynamics, diffusion and the maximum entropy production principle) to frame the theory. Given that open systems such as ecosystems will move towards maximizing dispersal of energy, we expect biological diversity to increase towards a level,...

  13. Art and brain: insights from neuropsychology, biology and evolution.

    Science.gov (United States)

    Zaidel, Dahlia W

    2010-02-01

    Art is a uniquely human activity associated fundamentally with symbolic and abstract cognition. Its practice in human societies throughout the world, coupled with seeming non-functionality, has led to three major brain theories of art. (1) The localized brain regions and pathways theory links art to multiple neural regions. (2) The display of art and its aesthetics theory is tied to the biological motivation of courtship signals and mate selection strategies in animals. (3) The evolutionary theory links the symbolic nature of art to critical pivotal brain changes in Homo sapiens supporting increased development of language and hierarchical social grouping. Collectively, these theories point to art as a multi-process cognition dependent on diverse brain regions and on redundancy in art-related functional representation.

  14. Three Southern high school biology teachers' perspectives on teaching evolution: Sociocultural influences

    Science.gov (United States)

    Kyzer, Peggy Mckewen

    Organizations in science and science education call for students to have a thorough understanding of the theory of evolution. Yet many high school biology teachers do not teach evolution and/or include creationism in their instruction (National Academy of Science, 1998). Historically, the controversy surrounding evolution has created tension for teachers. This case study explored the sociocultural influences related to teaching evolution in three Southern 10th-grade public high school biology classrooms. It also explored the socially and culturally embedded influences on teachers' instructional goals and personal perspectives toward evolution as well as modification of instruction when evolution is taught. Theoretically framed using symbolic interactionism and sociocultural theory, data were collected between October 2003 and April 2004 and included classroom observations two to three times per week, artifacts, and in-depth interviews of the participating teachers, their science department chairpersons, their students, and a Protestant minister. The classroom teachers were unaware of the focus of the study until after evolution was taught. The analysis used in this study was an inductive, interpretative approach that allowed exploration of the sociocultural influences that affect how teachers teach evolution. The sociocultural influences and the lived experiences of each teacher created a continuum for teaching evolution. One of the participating teachers who was heavily involved in the community and one of its fundamentalist churches elected to avoid teaching evolution. Another participating teacher at the same school integrated the theory of evolution in every unit. The third teacher who taught in another school elected to teach evolution in a superficial manner to avoid conflict. The data revealed that the participating teachers' sociocultural situatedness influenced their decisions and instruction on evolution. The influence of strong religious beliefs within

  15. Contingency, convergence and hyper-astronomical numbers in biological evolution.

    Science.gov (United States)

    Louis, Ard A

    2016-08-01

    Counterfactual questions such as "what would happen if you re-run the tape of life?" turn on the nature of the landscape of biological possibilities. Since the number of potential sequences that store genetic information grows exponentially with length, genetic possibility spaces can be so unimaginably vast that commentators frequently reach of hyper-astronomical metaphors that compare their size to that of the universe. Re-run the tape of life and the likelihood of encountering the same sequences in such hyper-astronomically large spaces is infinitesimally small, suggesting that evolutionary outcomes are highly contingent. On the other hand, the wide-spread occurrence of evolutionary convergence implies that similar phenotypes can be found again with relative ease. How can this be? Part of the solution to this conundrum must lie in the manner that genotypes map to phenotypes. By studying simple genotype-phenotype maps, where the counterfactual space of all possible phenotypes can be enumerated, it is shown that strong bias in the arrival of variation may explain why certain phenotypes are (repeatedly) observed in nature, while others never appear. This biased variation provides a non-selective cause for certain types of convergence. It illustrates how the role of randomness and contingency may differ significantly between genetic and phenotype spaces.

  16. gcodeml: A Grid-enabled Tool for Detecting Positive Selection in Biological Evolution

    CERN Document Server

    Moretti, Sébastien; Maffioletti, Sergio; Kuzniar, Arnold; Castella, Briséïs; Salamin, Nicolas; Robinson-Rechavi, Marc; Stockinger, Heinz

    2012-01-01

    One of the important questions in biological evolution is to know if certain changes along protein coding genes have contributed to the adaptation of species. This problem is known to be biologically complex and computationally very expensive. It, therefore, requires efficient Grid or cluster solutions to overcome the computational challenge. We have developed a Grid-enabled tool (gcodeml) that relies on the PAML (codeml) package to help analyse large phylogenetic datasets on both Grids and computational clusters. Although we report on results for gcodeml, our approach is applicable and customisable to related problems in biology or other scientific domains.

  17. The search for life's origins: Progress and future directions in planetary biology and chemical evolution

    Science.gov (United States)

    1990-01-01

    The current state is reviewed of the study of chemical evolution and planetary biology and the probable future is discussed of the field, at least for the near term. To this end, the report lists the goals and objectives of future research and makes detailed, comprehensive recommendations for accomplishing them, emphasizing those issues that were inadequately discussed in earlier Space Studies Board reports.

  18. Use of the "Tree" Analogy in Evolution Teaching by Biology Teachers

    Science.gov (United States)

    Marcelos, Maria Fatima; Nagem, Ronaldo Luiz

    2012-01-01

    This work discusses the use of Darwin's "Tree of Life" as a didactic analogy and metaphor in teaching evolution. It investigates whether biology teachers of pupils from 17 to 18 years old know Darwin's text "Tree of Life". In addition, it examines whether those teachers systematically employ either the analogies present in that…

  19. Nothing in Biology Makes Sense Except in the Light of Evolution

    Science.gov (United States)

    Dobzhansky, Theodosius

    1973-01-01

    Theory of evolution is not fact but is a scientific theory based on numerous pieces of concrete evidence. The only way to disprove this theory is to show evidence against it. The creationist view cannot be accepted in the light of new knowledge in molecular biology and other fields. (PS)

  20. Science for Survival: The Modern Synthesis of Evolution and The Biological Sciences Curriculum Study

    Science.gov (United States)

    Green, Lisa Anne

    In this historical dissertation, I examined the process of curriculum development in the Biological Sciences Curriculum Study (BSCS) in the United States during the period 1959-1963. The presentation of evolution in the high school texts was based on a more robust form of Darwinian evolution which developed during the 1930s and 1940s called "the modern synthesis of evolution." Building primarily on the work of historians Vassiliki Smocovitis and John L. Rudolph, I used the archival papers and published writings of the four architects of the modern synthesis and the four most influential leaders of the BSCS in regards to evolution to investigate how the modern synthetic theory of evolution shaped the BSCS curriculum. The central question was "Why was evolution so important to the BSCS to make it the central theme of the texts?" Important answers to this question had already been offered in the historiography, but it was still not clear why every citizen in the world needed to understand evolution. I found that the emphasis on natural selection in the modern synthesis shifted the focus away from humans as passive participants to the recognition that humans are active agents in their own cultural and biological evolution. This required re-education of the world citizenry, which was accomplished in part by the BSCS textbooks. I also found that BSCS leaders Grobman, Glass, and Muller had serious concerns regarding the effects of nuclear radiation on the human gene pool, and were actively involved in informing th public. Lastly, I found that concerns of 1950s reform eugenicists were addressed in the BSCS textbooks, without mentioning eugenics by name. I suggest that the leaders of the BSCS, especially Bentley Glass and Hermann J. Muller, thought that students needed to understand genetics and evolution to be able to make some of the tough choices they might be called on to make as the dominant species on earth and the next reproductive generation in the nuclear age. This

  1. Evolution in the Caribbean Classroom: A critical analysis of the role of biology teachers and science standards in shaping evolution instruction in Belize

    Science.gov (United States)

    Nunez, Elvis Enrique; Pringle, Rose M.; Showalter, Kevin Tyler

    2012-10-01

    A survey of the literature on evolution instruction provides evidence that teachers' personal views and understandings can shape instructional approaches and content delivered in science classrooms regardless of established science standards. This study is the first to quantify evolutionary worldviews of in-service teachers in the Caribbean, specifically in Belize, an English-speaking nation with a high school system guided by a regional biology syllabus and strict standardized tests. Using the Measure of Acceptance of the Theory of Evolution (MATE) instrument and knowledge test, we investigated (1) the current level of acceptance and understanding of evolution as given by 97% of high school biology teachers in Belize; (2) the factors associated with acceptance and understanding of evolutionary theory. With an average MATE score of 64.4 and a mean knowledge score of 47.9%, Belizean teachers were classified as having both 'Low Acceptance' and 'Low Understanding' of evolutionary theory. A positive correlation was found between teacher acceptance and understanding of evolution. A review of the Caribbean Secondary Examination Certificate biology syllabus suggests that evolution plays a minimal role in the high school biology classroom. We believe that Belize presents a unique opening for future training on evolution instruction since 57% of the biology teachers self-proclaim to be unprepared to teach evolution. The results of this study have implications for policy, practice and research with teachers' acceptance, understanding and confidence in teaching evolution serving as important predictors for instructional approaches used in the biology classroom.

  2. Punctuated equilibrium and shock waves in molecular models of biological evolution.

    Science.gov (United States)

    Saakian, David B; Ghazaryan, Makar H; Hu, Chin-Kun

    2014-08-01

    We consider the dynamics in infinite population evolution models with a general symmetric fitness landscape. We find shock waves, i.e., discontinuous transitions in the mean fitness, in evolution dynamics even with smooth fitness landscapes, which means that the search for the optimal evolution trajectory is more complicated. These shock waves appear in the case of positive epistasis and can be used to represent punctuated equilibria in biological evolution during long geological time scales. We find exact analytical solutions for discontinuous dynamics at the large-genome-length limit and derive optimal mutation rates for a fixed fitness landscape to send the population from the initial configuration to some final configuration in the fastest way.

  3. Markov Chain-Like Quantum Biological Modeling of Mutations, Aging, and Evolution

    Directory of Open Access Journals (Sweden)

    Ivan B. Djordjevic

    2015-08-01

    Full Text Available Recent evidence suggests that quantum mechanics is relevant in photosynthesis, magnetoreception, enzymatic catalytic reactions, olfactory reception, photoreception, genetics, electron-transfer in proteins, and evolution; to mention few. In our recent paper published in Life, we have derived the operator-sum representation of a biological channel based on codon basekets, and determined the quantum channel model suitable for study of the quantum biological channel capacity. However, this model is essentially memoryless and it is not able to properly model the propagation of mutation errors in time, the process of aging, and evolution of genetic information through generations. To solve for these problems, we propose novel quantum mechanical models to accurately describe the process of creation spontaneous, induced, and adaptive mutations and their propagation in time. Different biological channel models with memory, proposed in this paper, include: (i Markovian classical model, (ii Markovian-like quantum model, and (iii hybrid quantum-classical model. We then apply these models in a study of aging and evolution of quantum biological channel capacity through generations. We also discuss key differences of these models with respect to a multilevel symmetric channel-based Markovian model and a Kimura model-based Markovian process. These models are quite general and applicable to many open problems in biology, not only biological channel capacity, which is the main focus of the paper. We will show that the famous quantum Master equation approach, commonly used to describe different biological processes, is just the first-order approximation of the proposed quantum Markov chain-like model, when the observation interval tends to zero. One of the important implications of this model is that the aging phenotype becomes determined by different underlying transition probabilities in both programmed and random (damage Markov chain-like models of aging, which

  4. Markov Chain-Like Quantum Biological Modeling of Mutations, Aging, and Evolution.

    Science.gov (United States)

    Djordjevic, Ivan B

    2015-08-24

    Recent evidence suggests that quantum mechanics is relevant in photosynthesis, magnetoreception, enzymatic catalytic reactions, olfactory reception, photoreception, genetics, electron-transfer in proteins, and evolution; to mention few. In our recent paper published in Life, we have derived the operator-sum representation of a biological channel based on codon basekets, and determined the quantum channel model suitable for study of the quantum biological channel capacity. However, this model is essentially memoryless and it is not able to properly model the propagation of mutation errors in time, the process of aging, and evolution of genetic information through generations. To solve for these problems, we propose novel quantum mechanical models to accurately describe the process of creation spontaneous, induced, and adaptive mutations and their propagation in time. Different biological channel models with memory, proposed in this paper, include: (i) Markovian classical model, (ii) Markovian-like quantum model, and (iii) hybrid quantum-classical model. We then apply these models in a study of aging and evolution of quantum biological channel capacity through generations. We also discuss key differences of these models with respect to a multilevel symmetric channel-based Markovian model and a Kimura model-based Markovian process. These models are quite general and applicable to many open problems in biology, not only biological channel capacity, which is the main focus of the paper. We will show that the famous quantum Master equation approach, commonly used to describe different biological processes, is just the first-order approximation of the proposed quantum Markov chain-like model, when the observation interval tends to zero. One of the important implications of this model is that the aging phenotype becomes determined by different underlying transition probabilities in both programmed and random (damage) Markov chain-like models of aging, which are mutually

  5. Unbounded growth patterns of reproducing, competing polymers—similarities to biological evolution

    Science.gov (United States)

    Gregor Worst, Emanuel; Zimmer, Philipp; Wollrab, Eva; Kruse, Karsten; Ott, Albrecht

    2016-10-01

    Since the origin of life the interplay between reproduction, variation, and selection has been driving the emergence of new species. The evolution of the Earth’s biosphere appears to innovate unceasingly instead of coming to a stall. Here, we introduce a model system of linear molecules where new polymers appear by spontaneous ligation. The polymers proliferate following a template-based mechanism. Our combined experimental and theoretical study shows that for sufficiently rapid autocatalysis the reproduction process selects particular lengths—while ever longer polymers emerge. We suggest similarities to biological evolution.

  6. Human evolution, life history theory, and the end of biological reproduction.

    Science.gov (United States)

    Last, Cadell

    2014-01-01

    Throughout primate history there have been three major life history transitions towards increasingly delayed sexual maturation and biological reproduction, as well as towards extended life expectancy. Monkeys reproduce later and live longer than do prosimians, apes reproduce later and live longer than do monkeys, and humans reproduce later and live longer than do apes. These life history transitions are connected to increased encephalization. During the last life history transition from apes to humans, increased encephalization co-evolved with increased dependence on cultural knowledge for energy acquisition. This led to a dramatic pressure for more energy investment in growth over current biological reproduction. Since the industrial revolution socioeconomic development has led to even more energy being devoted to growth over current biological reproduction. I propose that this is the beginning of an ongoing fourth major primate life history transition towards completely delayed biological reproduction and an extension of the evolved human life expectancy. I argue that the only fundamental difference between this primate life history transition and previous life history transitions is that this transition is being driven solely by cultural evolution, which may suggest some deeper evolutionary transition away from biological evolution is already in the process of occurring.

  7. The Biological Big Bang model for the major transitions in evolution

    Science.gov (United States)

    Koonin, Eugene V

    2007-01-01

    Background Major transitions in biological evolution show the same pattern of sudden emergence of diverse forms at a new level of complexity. The relationships between major groups within an emergent new class of biological entities are hard to decipher and do not seem to fit the tree pattern that, following Darwin's original proposal, remains the dominant description of biological evolution. The cases in point include the origin of complex RNA molecules and protein folds; major groups of viruses; archaea and bacteria, and the principal lineages within each of these prokaryotic domains; eukaryotic supergroups; and animal phyla. In each of these pivotal nexuses in life's history, the principal "types" seem to appear rapidly and fully equipped with the signature features of the respective new level of biological organization. No intermediate "grades" or intermediate forms between different types are detectable. Usually, this pattern is attributed to cladogenesis compressed in time, combined with the inevitable erosion of the phylogenetic signal. Hypothesis I propose that most or all major evolutionary transitions that show the "explosive" pattern of emergence of new types of biological entities correspond to a boundary between two qualitatively distinct evolutionary phases. The first, inflationary phase is characterized by extremely rapid evolution driven by various processes of genetic information exchange, such as horizontal gene transfer, recombination, fusion, fission, and spread of mobile elements. These processes give rise to a vast diversity of forms from which the main classes of entities at the new level of complexity emerge independently, through a sampling process. In the second phase, evolution dramatically slows down, the respective process of genetic information exchange tapers off, and multiple lineages of the new type of entities emerge, each of them evolving in a tree-like fashion from that point on. This biphasic model of evolution incorporates the

  8. The Biological Big Bang model for the major transitions in evolution

    Directory of Open Access Journals (Sweden)

    Koonin Eugene V

    2007-08-01

    Full Text Available Abstract Background Major transitions in biological evolution show the same pattern of sudden emergence of diverse forms at a new level of complexity. The relationships between major groups within an emergent new class of biological entities are hard to decipher and do not seem to fit the tree pattern that, following Darwin's original proposal, remains the dominant description of biological evolution. The cases in point include the origin of complex RNA molecules and protein folds; major groups of viruses; archaea and bacteria, and the principal lineages within each of these prokaryotic domains; eukaryotic supergroups; and animal phyla. In each of these pivotal nexuses in life's history, the principal "types" seem to appear rapidly and fully equipped with the signature features of the respective new level of biological organization. No intermediate "grades" or intermediate forms between different types are detectable. Usually, this pattern is attributed to cladogenesis compressed in time, combined with the inevitable erosion of the phylogenetic signal. Hypothesis I propose that most or all major evolutionary transitions that show the "explosive" pattern of emergence of new types of biological entities correspond to a boundary between two qualitatively distinct evolutionary phases. The first, inflationary phase is characterized by extremely rapid evolution driven by various processes of genetic information exchange, such as horizontal gene transfer, recombination, fusion, fission, and spread of mobile elements. These processes give rise to a vast diversity of forms from which the main classes of entities at the new level of complexity emerge independently, through a sampling process. In the second phase, evolution dramatically slows down, the respective process of genetic information exchange tapers off, and multiple lineages of the new type of entities emerge, each of them evolving in a tree-like fashion from that point on. This biphasic model

  9. THE EVOLUTION OF THE KREBS CYCLE: A PROMISING THEME FOR MEANINGFUL BIOCHEMISTRY LEARNING IN BIOLOGY

    OpenAIRE

    Costa, C; E. Galembeck

    2015-01-01

    INTRODUCTION: Evolution has been recognized as a key concept for biologists. In order to motivate biology undergraduates for contents of central energetic metabolism, we addressed the Krebs cycle structure and functions to an evolutionary view. To this end, we created a study guide which contextualizes the emergence of the cyclic pathway, in light of the prokaryotic influence since early Earth anaerobic condition to oxygen rise in atmosphere. OBJECTIVES: The main goal is to highlight the educ...

  10. A hypothesis on the biological origins and social evolution of music and dance

    OpenAIRE

    Tianyan eWang

    2015-01-01

    The origins of music and musical emotions is still an enigma, here I propose a comprehensive hypothesis on the origins and evolution of music, dance, and speech from a biological and sociological perspective. I suggest that every pitch interval between neighboring notes in music represents corresponding movement pattern through interpreting the Doppler effect of sound, which not only provides a possible explanation for the transposition invariance of music, but also integrates music and dance...

  11. Reconstructing Anaximander's biological model unveils a theory of evolution akin to Darwin's, though centuries before the birth of science.

    Science.gov (United States)

    Trevisanato, Siro Igino

    2016-08-01

    Anaximander's fragments on biology report a theory of evolution, which, unlike the development of other biological systems in the ancient Aegean, is naturalistic and is not based on metaphysics. According to Anaximander, evolution affected all living beings, including humans. The first biological systems formed in an aquatic environment, and were encased in a rugged and robust envelope. Evolution progressed with modifications that enabled the formation of more dynamic biological systems. For instance, after reaching land, the robust armors around aquatic beings dried up, and became brittle, This led to the loss of the armor and the development of more mobile life forms. Anaximander's theory combines observations of animals with speculations, and as such mirrors the more famous theory of evolution by Charles Darwin expressed 24 centuries later. The poor reception received by Anaximander's model in his time, illustrates a zeitgeist that would explain the contemporary lag phase in the development of biology and, as a result, medicine, in the ancient western world.

  12. Why flavins are not competitors of chlorophyll in the evolution of biological converters of solar energy.

    Science.gov (United States)

    Kritsky, Mikhail S; Telegina, Taisiya A; Vechtomova, Yulia L; Buglak, Andrey A

    2012-12-27

    Excited flavin molecules can photocatalyze reactions, leading to the accumulation of free energy in the products, and the data accumulated through biochemical experiments and by modeling prebiological processes suggest that flavins were available in the earliest stages of evolution. Furthermore, model experiments have shown that abiogenic flavin conjugated with a polyamino acid matrix, a pigment that photocatalyzes the phosphorylation of ADP to form ATP, could have been present in the prebiotic environment. Indeed, excited flavin molecules play key roles in many photoenzymes and regulatory photoreceptors, and the substantial structural differences between photoreceptor families indicate that evolution has repeatedly used flavins as chromophores for photoreceptor proteins. Some of these photoreceptors are equipped with a light-harvesting antenna, which transfers excitation energy to chemically reactive flavins in the reaction center. The sum of the available data suggests that evolution could have led to the formation of a flavin-based biological converter to convert light energy into energy in the form of ATP.

  13. Directed evolution combined with synthetic biology strategies expedite semi-rational engineering of genes and genomes.

    Science.gov (United States)

    Kang, Zhen; Zhang, Junli; Jin, Peng; Yang, Sen

    2015-01-01

    Owing to our limited understanding of the relationship between sequence and function and the interaction between intracellular pathways and regulatory systems, the rational design of enzyme-coding genes and de novo assembly of a brand-new artificial genome for a desired functionality or phenotype are difficult to achieve. As an alternative approach, directed evolution has been widely used to engineer genomes and enzyme-coding genes. In particular, significant developments toward DNA synthesis, DNA assembly (in vitro or in vivo), recombination-mediated genetic engineering, and high-throughput screening techniques in the field of synthetic biology have been matured and widely adopted, enabling rapid semi-rational genome engineering to generate variants with desired properties. In this commentary, these novel tools and their corresponding applications in the directed evolution of genomes and enzymes are discussed. Moreover, the strategies for genome engineering and rapid in vitro enzyme evolution are also proposed.

  14. MBEToolbox: a Matlab toolbox for sequence data analysis in molecular biology and evolution

    Directory of Open Access Journals (Sweden)

    Xia Xuhua

    2005-03-01

    Full Text Available Abstract Background MATLAB is a high-performance language for technical computing, integrating computation, visualization, and programming in an easy-to-use environment. It has been widely used in many areas, such as mathematics and computation, algorithm development, data acquisition, modeling, simulation, and scientific and engineering graphics. However, few functions are freely available in MATLAB to perform the sequence data analyses specifically required for molecular biology and evolution. Results We have developed a MATLAB toolbox, called MBEToolbox, aimed at filling this gap by offering efficient implementations of the most needed functions in molecular biology and evolution. It can be used to manipulate aligned sequences, calculate evolutionary distances, estimate synonymous and nonsynonymous substitution rates, and infer phylogenetic trees. Moreover, it provides an extensible, functional framework for users with more specialized requirements to explore and analyze aligned nucleotide or protein sequences from an evolutionary perspective. The full functions in the toolbox are accessible through the command-line for seasoned MATLAB users. A graphical user interface, that may be especially useful for non-specialist end users, is also provided. Conclusion MBEToolbox is a useful tool that can aid in the exploration, interpretation and visualization of data in molecular biology and evolution. The software is publicly available at http://web.hku.hk/~jamescai/mbetoolbox/ and http://bioinformatics.org/project/?group_id=454.

  15. Mapping biological ideas: Concept maps as knowledge integration tools for evolution education

    Science.gov (United States)

    Schwendimann, Beat Adrian

    Many students leave school with a fragmented understanding of biology that does not allow them to connect their ideas to their everyday lives (Wandersee, 1989; Mintzes, Wandersee, & Novak, 1998; Mintzes, Wandersee, & Novak, 2000a). Understanding evolution ideas is seen as central to building an integrated knowledge of biology (Blackwell, Powell, & Dukes, 2003; Thagard & Findlay, 2010). However, the theory of evolution has been found difficult to understand as it incorporates a wide range of ideas from different areas (Bahar et al., 1999; Tsui & Treagust, 2003) and multiple interacting levels (Wilensky & Resnick, 1999; Duncan & Reiser, 2007; Hmelo-Silver et al., 2007). Research suggests that learners can hold a rich repertoire of co-existing alternative ideas of evolution (for example, Bishop & Anderson, 1990; Demastes, Good, & Peebles, 1996; Evans, 2008), especially of human evolution (for example, Nelson, 1986; Sinatra et al., 2003; Poling & Evans, 2004). Evolution ideas are difficult to understand because they often contradict existing alternative ideas (Mayr, 1982; Wolpert, 1994; Evans, 2008). Research suggests that understanding human evolution is a key to evolution education (for example, Blackwell et al., 2003; Besterman & Baggott la Velle, 2007). This dissertation research investigates how different concept mapping forms embedded in a collaborative technology-enhanced learning environment can support students' integration of evolution ideas using case studies of human evolution. Knowledge Integration (KI) (Linn et al., 2000; Linn et al., 2004) is used as the operational framework to explore concept maps as knowledge integration tools to elicit, add, critically distinguish, group, connect, and sort out alternative evolution ideas. Concept maps are a form of node-link diagram for organizing and representing connections between ideas as a semantic network (Novak & Gowin, 1984). This dissertation research describes the iterative development of a novel biology

  16. Does the nature of science influence college students' learning of biological evolution?

    Science.gov (United States)

    Butler, Wilbert, Jr.

    This quasi-experimental, mixed-methods study assessed the influence of the nature of science (NOS) instruction on college students' learning of biological evolution. In this research, conducted in two introductory biology courses, in each course the same instruction was employed, with one important exception: in the experimental section students were involved in an explicit, reflective treatment of the nature of science (Explicit, reflective NOS), in the traditional treatment section, NOS was implicitly addressed (traditional treatment). In both sections, NOS aspects of science addressed included is tentative, empirically based, subjective, inferential, and based on relationship between scientific theories and laws. Students understanding of evolution, acceptance of evolution, and understanding of the nature of science were assessed before, during and after instruction. Data collection entailed qualitative and quantitative methods including Concept Inventory for Natural Selection (CINS), Measure of Acceptance of the Theory of Evolution (MATE) survey, Views of nature of Science (VNOS-B survey), as well as interviews, classroom observations, and journal writing to address understand students' views of science and understanding and acceptance of evolution. The quantitative data were analyzed via inferential statistics and the qualitative data were analyzed using grounded theory. The data analysis allowed for the construction and support for four assertions: Assertion 1: Students engaged in explicit and reflective NOS specific instruction significantly improved their understanding of the nature of science concepts. Alternatively, students engaged in instruction using an implicit approach to the nature of science did not improve their understanding of the nature of science to the same degree. The VNOS-B results indicated that students in the explicit, reflective NOS class showed the better understanding of the NOS after the course than students in the implicit NOS class

  17. Evolution of Marine Organisms under Climate Change at Different Levels of Biological Organisation

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    Ben P. Harvey

    2014-11-01

    Full Text Available Research to date has suggested that both individual marine species and ecological processes are expected to exhibit diverse responses to the environmental effects of climate change. Evolutionary responses can occur on rapid (ecological timescales, and yet studies typically do not consider the role that adaptive evolution will play in modulating biological responses to climate change. Investigations into such responses have typically been focused at particular biological levels (e.g., cellular, population, community, often lacking interactions among levels. Since all levels of biological organisation are sensitive to global climate change, there is a need to elucidate how different processes and hierarchical interactions will influence species fitness. Therefore, predicting the responses of communities and populations to global change will require multidisciplinary efforts across multiple levels of hierarchy, from the genetic and cellular to communities and ecosystems. Eventually, this may allow us to establish the role that acclimatisation and adaptation will play in determining marine community structures in future scenarios.

  18. A Novel Application of Synthetic Biology and Directed Evolution to Engineer Phage-based Antibiotics

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Meiye [Sandia National Lab. (SNL-CA), Livermore, CA (United States)

    2014-09-01

    The emergence of multiple drug resistant bacteria poses threats to human health, agriculture and food safety. Annually over 100,000 deaths and up to $20 billion loss to the U.S. economy are attributed to multiple drug resistant bacteria. With only four new chemical antibiotics in the drug development pipeline, we are in dire need of new solutions to address the emerging threat of multiple drug resistance. We propose a paradigm-changing approach to address the multi-drug resistant bacteria problem by utilizing Synthetic Biology (SynBio) methodologies to create and evolve “designer” bacteriophages or phages – viruses that specifically infect bacteria – to infect and kill newly emerging pathogenic bacterial strains WITHOUT the need for chemical antibiotics. A major advantage of using phage to combat pathogenic bacteria is that phages can co-evolve with their bacterial host, and Sandia can be the first in the world to establish an industrial scale Synthetic Biology pipeline for phage directed evolution for safe, targeted, customizable solution to bacterial drug resistance. Since there is no existing phage directed evolution effort within or outside of Sandia, this proposal is suitable as a high-risk LDRD effort to create the first pipeline for such an endeavor. The high potential reward nature of this proposal will be the immediate impact in decontamination and restoration of surfaces and infrastructure, with longer term impact in human or animal therapeutics. The synthetic biology and screening approaches will lead to fundamental knowledge of phage/bacteria co-evolution, making Sandia a world leader in directed evolution of bacteriophages.

  19. Biological adaptations for functional features of language in the face of cultural evolution.

    Science.gov (United States)

    Christiansen, Morten H; Reali, Florencia; Chater, Nick

    2011-04-01

    Although there may be no true language universals, it is nonetheless possible to discern several family resemblance patterns across the languages of the world. Recent work on the cultural evolution of language indicates the source of these patterns is unlikely to be an innate universal grammar evolved through biological adaptations for arbitrary linguistic features. Instead, it has been suggested that the patterns of resemblance emerge because language has been shaped by the brain, with individual languages representing different but partially overlapping solutions to the same set of nonlinguistic constraints. Here, we use computational simulations to investigate whether biological adaptation for functional features of language, deriving from cognitive and communicative constraints, may nonetheless be possible alongside rapid cultural evolution. Specifically, we focus on the Baldwin effect as an evolutionary mechanism by which previously learned linguistic features might become innate through natural selection across many generations of language users. The results indicate that cultural evolution of language does not necessarily prevent functional features of language from becoming genetically fixed, thus potentially providing a particularly informative source of constraints on cross-linguistic resemblance patterns.

  20. Use of the "Tree" Analogy in Evolution Teaching by Biology Teachers

    Science.gov (United States)

    Marcelos, Maria Fátima; Nagem, Ronaldo Luiz

    2012-04-01

    This work discusses the use of Darwin's `Tree of Life' as a didactic analogy and metaphor in teaching evolution. It investigates whether biology teachers of pupils from 17 to 18 years old know Darwin's text `Tree of Life'. In addition, it examines whether those teachers systematically employ either the analogies present in that text or other analogies between the tree and evolution, and whether they adopt a specific methodology for teaching with analogies and metaphors (A&M). The academic training of teachers regarding use of A&M is review briefly. A diagnostic study was carried out with biology teachers in a public school in the town of Contagem in the state of Minas Gerais in Brazil. The data were obtained through direct observation, questionnaires and a focus group. The teachers pointed out in the questionnaires that some details of Darwin's analogy are utilized as a resource. However, analysis of the data indicates that the `Tree of Life' text is not known or utilized in class. At the same time, the teachers state that they use aspects of the tree as a didactic resource to teach evolution and that its use facilitates the learning of content. The teachers have little knowledge of specific methodologies of teaching with analogies and metaphors, revealing that their training is incomplete in this area.

  1. Mobility as an emergent property of biological organization: Insights from experimental evolution.

    Science.gov (United States)

    Wallace, Ian J; Garland, Theodore

    2016-05-06

    Anthropologists accept that mobility is a critical dimension of human culture, one that links economy, technology, and social relations. Less often acknowledged is that mobility depends on complex and dynamic interactions between multiple levels of our biological organization, including anatomy, physiology, neurobiology, and genetics. Here, we describe a novel experimental approach to examining the biological foundations of mobility, using mice from a long-term artificial selection experiment for high levels of voluntary exercise on wheels. In this experiment, mice from selectively bred lines have evolved to run roughly three times as far per day as those from nonselected control lines. We consider three insights gleaned from this experiment as foundational principles for the study of mobility from the perspective of biological evolution. First, an evolutionary change in mobility will necessarily be associated with alterations in biological traits both directly and indirectly connected to mobility. Second, changing mobility will result in trade-offs and constraints among some of the affected traits. Third, multiple solutions exist to altering mobility, so that various combinations of adjustments to traits linked with mobility can achieve the same overall behavioral outcome. We suggest that anthropological knowledge of variation in human mobility might be improved by greater research attention to its biological dimensions.

  2. Controversy in Biology Classrooms-Citizen Science Approaches to Evolution and Applications to Climate Change Discussions.

    Science.gov (United States)

    Yoho, Rachel A; Vanmali, Binaben H

    2016-03-01

    The biological sciences encompass topics considered controversial by the American public, such as evolution and climate change. We believe that the development of climate change education in the biology classroom is better informed by an understanding of the history of the teaching of evolution. A common goal for science educators should be to engender a greater respect for and appreciation of science among students while teaching specific content knowledge. Citizen science has emerged as a viable yet underdeveloped method for engaging students of all ages in key scientific issues that impact society through authentic data-driven scientific research. Where successful, citizen science may open avenues of communication and engagement with the scientific process that would otherwise be more difficult to achieve. Citizen science projects demonstrate versatility in education and the ability to test hypotheses by collecting large amounts of often publishable data. We find a great possibility for science education research in the incorporation of citizen science projects in curriculum, especially with respect to "hot topics" of socioscientific debate based on our review of the findings of other authors. Journal of Microbiology & Biology Education.

  3. The evolution of the Faculty of Language from a Chomskyan perspective: bridging linguistics and biology.

    Science.gov (United States)

    Longa, Victor Manuel

    2013-01-01

    While language was traditionally considered a purely cultural trait, the advent of Noam Chomsky's Generative Grammar in the second half of the twentieth century dramatically challenged that view. According to that theory, language is an innate feature, part of the human biological endowment. If language is indeed innate, it had to biologically evolve. This review has two main objectives: firstly, it characterizes from a Chomskyan perspective the evolutionary processes by which language could have come into being. Secondly, it proposes a new method for interpreting the archaeological record that radically differs from the usual types of evidence Paleoanthropology has concentrated on when dealing with language evolution: while archaeological remains have usually been regarded from the view of the behavior they could be associated with, the paper will consider archaeological remains from the view of the computational processes and capabilities at work for their production. This computational approach, illustrated with a computational analysis of prehistoric geometric engravings, will be used to challenge the usual generative thinking on language evolution, based on the high specificity of language. The paper argues that the biological machinery of language is neither specifically linguistic nor specifically human, although language itself can still be considered a species-specific innate trait. From such a view, language would be one of the consequences of a slight modification operated on an ancestral architecture shared with vertebrates.

  4. Synthetic biology for the directed evolution of protein biocatalysts: navigating sequence space intelligently.

    Science.gov (United States)

    Currin, Andrew; Swainston, Neil; Day, Philip J; Kell, Douglas B

    2015-03-07

    The amino acid sequence of a protein affects both its structure and its function. Thus, the ability to modify the sequence, and hence the structure and activity, of individual proteins in a systematic way, opens up many opportunities, both scientifically and (as we focus on here) for exploitation in biocatalysis. Modern methods of synthetic biology, whereby increasingly large sequences of DNA can be synthesised de novo, allow an unprecedented ability to engineer proteins with novel functions. However, the number of possible proteins is far too large to test individually, so we need means for navigating the 'search space' of possible protein sequences efficiently and reliably in order to find desirable activities and other properties. Enzymologists distinguish binding (Kd) and catalytic (kcat) steps. In a similar way, judicious strategies have blended design (for binding, specificity and active site modelling) with the more empirical methods of classical directed evolution (DE) for improving kcat (where natural evolution rarely seeks the highest values), especially with regard to residues distant from the active site and where the functional linkages underpinning enzyme dynamics are both unknown and hard to predict. Epistasis (where the 'best' amino acid at one site depends on that or those at others) is a notable feature of directed evolution. The aim of this review is to highlight some of the approaches that are being developed to allow us to use directed evolution to improve enzyme properties, often dramatically. We note that directed evolution differs in a number of ways from natural evolution, including in particular the available mechanisms and the likely selection pressures. Thus, we stress the opportunities afforded by techniques that enable one to map sequence to (structure and) activity in silico, as an effective means of modelling and exploring protein landscapes. Because known landscapes may be assessed and reasoned about as a whole, simultaneously, this

  5. The Sensitivity of Earth's Climate History To Changes In The Rates of Biological And Geological Evolution

    Science.gov (United States)

    Waltham, D.

    2014-12-01

    The faint young Sun paradox (early Earth had surface liquid water despite solar luminosity 70% of the modern value) implies that our planet's albedo has increased through time and/or greenhouse warming has fallen. The obvious explanation is that negative feedback processes stabilized temperatures. However, the limited temperature data available does not exhibit the expected residual temperature rise and, at least for the Phanerozoic, estimates of climate sensitivity exceed the Planck sensitivity (the zero net-feedback value). The alternate explanation is that biological and geological evolution have tended to cool Earth through time hence countering solar-driven warming. The coincidence that Earth-evolution has roughly cancelled Solar-evolution can then be explained as an emergent property of a complex system (the Gaia hypothesis) or the result of the unavoidable observational bias that Earth's climate history must be compatible with our existence (the anthropic principle). Here, I use a simple climate model to investigate the sensitivity of Earth's climate to changes in the rate of Earth-evolution. Earth-evolution is represented by an effective emissivity which has an intrinsic variation through time (due to continental growth, the evolution of cyanobacteria, orbital fluctuations etc) plus a linear feedback term which enhances emissivity variations. An important feature of this model is a predicted maximum in the radiated-flux versus temperature function. If the increasing solar flux through time had exceeded this value then runaway warming would have occurred. For the best-guess temperature history and climate sensitivity, the Earth has always been within a few percent of this maximum. There is no obvious Gaian explanation for this flux-coincidence but the anthropic principle naturally explains it: If the rate of biological/geological evolution is naturally slow then Earth is a fortunate outlier which evolved just fast enough to avoid solar-induced over

  6. The genome sequence of taurine cattle: a window to ruminant biology and evolution.

    Science.gov (United States)

    Elsik, Christine G; Tellam, Ross L; Worley, Kim C; Gibbs, Richard A; Muzny, Donna M; Weinstock, George M; Adelson, David L; Eichler, Evan E; Elnitski, Laura; Guigó, Roderic; Hamernik, Debora L; Kappes, Steve M; Lewin, Harris A; Lynn, David J; Nicholas, Frank W; Reymond, Alexandre; Rijnkels, Monique; Skow, Loren C; Zdobnov, Evgeny M; Schook, Lawrence; Womack, James; Alioto, Tyler; Antonarakis, Stylianos E; Astashyn, Alex; Chapple, Charles E; Chen, Hsiu-Chuan; Chrast, Jacqueline; Câmara, Francisco; Ermolaeva, Olga; Henrichsen, Charlotte N; Hlavina, Wratko; Kapustin, Yuri; Kiryutin, Boris; Kitts, Paul; Kokocinski, Felix; Landrum, Melissa; Maglott, Donna; Pruitt, Kim; Sapojnikov, Victor; Searle, Stephen M; Solovyev, Victor; Souvorov, Alexandre; Ucla, Catherine; Wyss, Carine; Anzola, Juan M; Gerlach, Daniel; Elhaik, Eran; Graur, Dan; Reese, Justin T; Edgar, Robert C; McEwan, John C; Payne, Gemma M; Raison, Joy M; Junier, Thomas; Kriventseva, Evgenia V; Eyras, Eduardo; Plass, Mireya; Donthu, Ravikiran; Larkin, Denis M; Reecy, James; Yang, Mary Q; Chen, Lin; Cheng, Ze; Chitko-McKown, Carol G; Liu, George E; Matukumalli, Lakshmi K; Song, Jiuzhou; Zhu, Bin; Bradley, Daniel G; Brinkman, Fiona S L; Lau, Lilian P L; Whiteside, Matthew D; Walker, Angela; Wheeler, Thomas T; Casey, Theresa; German, J Bruce; Lemay, Danielle G; Maqbool, Nauman J; Molenaar, Adrian J; Seo, Seongwon; Stothard, Paul; Baldwin, Cynthia L; Baxter, Rebecca; Brinkmeyer-Langford, Candice L; Brown, Wendy C; Childers, Christopher P; Connelley, Timothy; Ellis, Shirley A; Fritz, Krista; Glass, Elizabeth J; Herzig, Carolyn T A; Iivanainen, Antti; Lahmers, Kevin K; Bennett, Anna K; Dickens, C Michael; Gilbert, James G R; Hagen, Darren E; Salih, Hanni; Aerts, Jan; Caetano, Alexandre R; Dalrymple, Brian; Garcia, Jose Fernando; Gill, Clare A; Hiendleder, Stefan G; Memili, Erdogan; Spurlock, Diane; Williams, John L; Alexander, Lee; Brownstein, Michael J; Guan, Leluo; Holt, Robert A; Jones, Steven J M; Marra, Marco A; Moore, Richard; Moore, Stephen S; Roberts, Andy; Taniguchi, Masaaki; Waterman, Richard C; Chacko, Joseph; Chandrabose, Mimi M; Cree, Andy; Dao, Marvin Diep; Dinh, Huyen H; Gabisi, Ramatu Ayiesha; Hines, Sandra; Hume, Jennifer; Jhangiani, Shalini N; Joshi, Vandita; Kovar, Christie L; Lewis, Lora R; Liu, Yih-Shin; Lopez, John; Morgan, Margaret B; Nguyen, Ngoc Bich; Okwuonu, Geoffrey O; Ruiz, San Juana; Santibanez, Jireh; Wright, Rita A; Buhay, Christian; Ding, Yan; Dugan-Rocha, Shannon; Herdandez, Judith; Holder, Michael; Sabo, Aniko; Egan, Amy; Goodell, Jason; Wilczek-Boney, Katarzyna; Fowler, Gerald R; Hitchens, Matthew Edward; Lozado, Ryan J; Moen, Charles; Steffen, David; Warren, James T; Zhang, Jingkun; Chiu, Readman; Schein, Jacqueline E; Durbin, K James; Havlak, Paul; Jiang, Huaiyang; Liu, Yue; Qin, Xiang; Ren, Yanru; Shen, Yufeng; Song, Henry; Bell, Stephanie Nicole; Davis, Clay; Johnson, Angela Jolivet; Lee, Sandra; Nazareth, Lynne V; Patel, Bella Mayurkumar; Pu, Ling-Ling; Vattathil, Selina; Williams, Rex Lee; Curry, Stacey; Hamilton, Cerissa; Sodergren, Erica; Wheeler, David A; Barris, Wes; Bennett, Gary L; Eggen, André; Green, Ronnie D; Harhay, Gregory P; Hobbs, Matthew; Jann, Oliver; Keele, John W; Kent, Matthew P; Lien, Sigbjørn; McKay, Stephanie D; McWilliam, Sean; Ratnakumar, Abhirami; Schnabel, Robert D; Smith, Timothy; Snelling, Warren M; Sonstegard, Tad S; Stone, Roger T; Sugimoto, Yoshikazu; Takasuga, Akiko; Taylor, Jeremy F; Van Tassell, Curtis P; Macneil, Michael D; Abatepaulo, Antonio R R; Abbey, Colette A; Ahola, Virpi; Almeida, Iassudara G; Amadio, Ariel F; Anatriello, Elen; Bahadue, Suria M; Biase, Fernando H; Boldt, Clayton R; Carroll, Jeffery A; Carvalho, Wanessa A; Cervelatti, Eliane P; Chacko, Elsa; Chapin, Jennifer E; Cheng, Ye; Choi, Jungwoo; Colley, Adam J; de Campos, Tatiana A; De Donato, Marcos; Santos, Isabel K F de Miranda; de Oliveira, Carlo J F; Deobald, Heather; Devinoy, Eve; Donohue, Kaitlin E; Dovc, Peter; Eberlein, Annett; Fitzsimmons, Carolyn J; Franzin, Alessandra M; Garcia, Gustavo R; Genini, Sem; Gladney, Cody J; Grant, Jason R; Greaser, Marion L; Green, Jonathan A; Hadsell, Darryl L; Hakimov, Hatam A; Halgren, Rob; Harrow, Jennifer L; Hart, Elizabeth A; Hastings, Nicola; Hernandez, Marta; Hu, Zhi-Liang; Ingham, Aaron; Iso-Touru, Terhi; Jamis, Catherine; Jensen, Kirsty; Kapetis, Dimos; Kerr, Tovah; Khalil, Sari S; Khatib, Hasan; Kolbehdari, Davood; Kumar, Charu G; Kumar, Dinesh; Leach, Richard; Lee, Justin C-M; Li, Changxi; Logan, Krystin M; Malinverni, Roberto; Marques, Elisa; Martin, William F; Martins, Natalia F; Maruyama, Sandra R; Mazza, Raffaele; McLean, Kim L; Medrano, Juan F; Moreno, Barbara T; Moré, Daniela D; Muntean, Carl T; Nandakumar, Hari P; Nogueira, Marcelo F G; Olsaker, Ingrid; Pant, Sameer D; Panzitta, Francesca; Pastor, Rosemeire C P; Poli, Mario A; Poslusny, Nathan; Rachagani, Satyanarayana; Ranganathan, Shoba; Razpet, Andrej; Riggs, Penny K; Rincon, Gonzalo; Rodriguez-Osorio, Nelida; Rodriguez-Zas, Sandra L; Romero, Natasha E; Rosenwald, Anne; Sando, Lillian; Schmutz, Sheila M; Shen, Libing; Sherman, Laura; Southey, Bruce R; Lutzow, Ylva Strandberg; Sweedler, Jonathan V; Tammen, Imke; Telugu, Bhanu Prakash V L; Urbanski, Jennifer M; Utsunomiya, Yuri T; Verschoor, Chris P; Waardenberg, Ashley J; Wang, Zhiquan; Ward, Robert; Weikard, Rosemarie; Welsh, Thomas H; White, Stephen N; Wilming, Laurens G; Wunderlich, Kris R; Yang, Jianqi; Zhao, Feng-Qi

    2009-04-24

    To understand the biology and evolution of ruminants, the cattle genome was sequenced to about sevenfold coverage. The cattle genome contains a minimum of 22,000 genes, with a core set of 14,345 orthologs shared among seven mammalian species of which 1217 are absent or undetected in noneutherian (marsupial or monotreme) genomes. Cattle-specific evolutionary breakpoint regions in chromosomes have a higher density of segmental duplications, enrichment of repetitive elements, and species-specific variations in genes associated with lactation and immune responsiveness. Genes involved in metabolism are generally highly conserved, although five metabolic genes are deleted or extensively diverged from their human orthologs. The cattle genome sequence thus provides a resource for understanding mammalian evolution and accelerating livestock genetic improvement for milk and meat production.

  7. Systems Biology Investigations of Pseudomonas aeruginosa Evolution in Association with Human Airway Infections

    DEFF Research Database (Denmark)

    Pedersen, Søren Damkiær

    Most knowledge about evolutionary adaptation has been gained from experimental evolution studies, in which organisms have been allowed to evolve under simple, well-defined conditions in the laboratory. While these studies have provided novel insight into the fundamental processes of evolutionary...... environments. The model system used for these investigations has been long-term chronic airway infections in Cystic fibrosis (CF) patients caused by the opportunistic pathogen Pseudomonas aeruginosa. Using a systems biology approach, we have monitored the adaptive development of the clinically important P....... aeruginosa DK2 clone lineage during 200,000 generations of evolution in the CF airways from its entrance in the clinic in the 1970’ies until the end of 2010. Genetic analysis showed that the DK2 lineage between 1973 and 2007 accumulated mutations in a near-linear manner with an overall genomic signature...

  8. Proceedings of Synthetic Biology: Engineering, Evolution and Design (SEED) Conference 2015

    Energy Technology Data Exchange (ETDEWEB)

    Silver, Pamela [Harvard Univ., Cambridge, MA (United States); SEED 2015 Conference Chair; Flach, Evan [American Institute of Chemical Engineers; SEED 2015 Conference Organizer

    2016-10-27

    Synthetic Biology is an emerging discipline that seeks to accelerate the process of engineering biology. As such, the tools are broadly applicable to application areas, including chemicals and biofuels, materials, medicine and agriculture. A characteristic of the field is to look holistically at cellular design, from sensing and genetic circuitry to the manipulation of cellular processes and actuators, to controlling metabolism, to programming multicellular behaviors. Further, the types of cells that are manipulated are broad, from in vitro systems to microbes and fungi to mammalian and plant cells and living animals. Many of the projects in synthetic biology seek to move biochemical functions across organisms. The field is highly interdisciplinary with faculty and students spread across departments that focus on engineering (biological, chemical, electrical, mechanical, civil, computer science) and basic science (biology and systems biology, chemistry, physics). While there have been many one-off workshops and meeting on synthetic biology, the 2014 Synthetic Biology: Engineering, Evolution and Design (SEED) was the first of an annual conference series that serves as a reliable place to pull together the involved disciplines in order to organize and exchange advances in the science and technology in the field. Further, the SEED conferences have a strong focus on industry, with many companies represented and actively participating. A number of these companies have started major efforts in synthetic biology including large companies (e.g., Pfizer, Novartis, Dow, Dupont, BP, Total), smaller companies have recently gone public (e.g., Amyris, Gevo, Intrexon), and many start-ups (e.g., Teslagen, Refactored Materials, Pivot, Genomatica). There are a number of loosely affiliated Synthetic Biology Centers, including ones at MIT, Boston University, UCSD, UCSF, UC-Berkeley, Imperial College, Oxford, and ETH. SEED 2015 will serve as the primary meeting at which international

  9. THE EVOLUTION OF THE KREBS CYCLE: A PROMISING THEME FOR MEANINGFUL BIOCHEMISTRY LEARNING IN BIOLOGY

    Directory of Open Access Journals (Sweden)

    C. Costa

    2015-08-01

    Full Text Available INTRODUCTION: Evolution has been recognized as a key concept for biologists. In order to motivate biology undergraduates for contents of central energetic metabolism, we addressed the Krebs cycle structure and functions to an evolutionary view. To this end, we created a study guide which contextualizes the emergence of the cyclic pathway, in light of the prokaryotic influence since early Earth anaerobic condition to oxygen rise in atmosphere. OBJECTIVES: The main goal is to highlight the educational potential of the material whose subject is scarcely covered in biochemistry textbooks. MATERIALS AND METHODS: The study guide is composed by three interrelated sections, the problem (Section 1, designed to arouse curiosity, inform and motivate students; an introductory text (Section 2 about life evolution, including early micro-organisms and Krebs cycle emergence, and questions (Section 3 for debate. The activity consisted on a peer discussion session, with instructors tutoring. The questions were designed to foster exchange of ideas in an ever-increasing level of complexity, and cover subjects from early atmospheric conditions to organization of the metabolism along the subsequent geological ages. RESULTS AND DISCUSSION: We noticed that students were engaged and motivated by the task, especially during group discussion. Based on students’ feedbacks and class observations, we learned that the material raised curiosity and stimulated discussion among peers. It brought a historical and purposeful way of dealing with difficult biochemical concepts. CONCLUSIONS: The whole experience suggests that the study guide was a stimulus for broadening comprehension of the Krebs cycle, reinforcing the evolutionary stance as an important theme for biology and biochemistry understanding. On the other hand, we do not underestimate the fact that approaching Krebs cycle from an evolutionary standpoint is a quite complex discussion for the majority of students

  10. From the ultrasonic to the infrared: molecular evolution and the sensory biology of bats.

    Science.gov (United States)

    Jones, Gareth; Teeling, Emma C; Rossiter, Stephen J

    2013-01-01

    Great advances have been made recently in understanding the genetic basis of the sensory biology of bats. Research has focused on the molecular evolution of candidate sensory genes, genes with known functions [e.g., olfactory receptor (OR) genes] and genes identified from mutations associated with sensory deficits (e.g., blindness and deafness). For example, the FoxP2 gene, underpinning vocal behavior and sensorimotor coordination, has undergone diversification in bats, while several genes associated with audition show parallel amino acid substitutions in unrelated lineages of echolocating bats and, in some cases, in echolocating dolphins, representing a classic case of convergent molecular evolution. Vision genes encoding the photopigments rhodopsin and the long-wave sensitive opsin are functional in bats, while that encoding the short-wave sensitive opsin has lost functionality in rhinolophoid bats using high-duty cycle laryngeal echolocation, suggesting a sensory trade-off between investment in vision and echolocation. In terms of olfaction, bats appear to have a distinctive OR repertoire compared with other mammals, and a gene involved in signal transduction in the vomeronasal system has become non-functional in most bat species. Bitter taste receptors appear to have undergone a "birth-and death" evolution involving extensive gene duplication and loss, unlike genes coding for sweet and umami tastes that show conservation across most lineages but loss in vampire bats. Common vampire bats have also undergone adaptations for thermoperception, via alternative splicing resulting in the evolution of a novel heat-sensitive channel. The future for understanding the molecular basis of sensory biology is promising, with great potential for comparative genomic analyses, studies on gene regulation and expression, exploration of the role of alternative splicing in the generation of proteomic diversity, and linking genetic mechanisms to behavioral consequences.

  11. From the ultrasonic to the infrared: molecular evolution and the sensory biology of bats

    Directory of Open Access Journals (Sweden)

    Gareth eJones

    2013-05-01

    Full Text Available Great advances have been made recently in understanding the genetic basis of the sensory biology of bats. Research has focused on the molecular evolution of candidate sensory genes, genes with known functions (e.g. olfactory receptor genes and genes identified from mutations associated with sensory deficits (e.g. blindness and deafness. For example, the FoxP2 gene, underpinning vocal behaviour and sensorimotor coordination, has undergone diversification in bats, while several genes associated with audition show parallel amino acid substitutions in unrelated lineages of echolocating bats and, in some cases, in echolocating dolphins, representing a classic case of convergent molecular evolution. Vision genes encoding the photopigments rhodopsin and the long-wave sensitive opsin are functional in bats, while that encoding the short-wave sensitive opsin has lost functionality in rhinolophoid bats using high-duty cycle laryngeal echolocation, suggesting a sensory trade-off between investment in vision and echolocation. In terms of olfaction, bats appear to have a distinctive olfactory receptor repertoire compared with other mammals, and a gene involved in signal transduction in the vomeronasal system has become non-functional in most bat species. Bitter taste receptors appear to have undergone a ‘birth-and death’ evolution involving extensive gene duplication and loss, unlike genes coding for sweet and umami tastes that show conservation across most lineages but loss in vampire bats. Common vampire bats have also undergone adaptations for thermoperception, via alternative splicing resulting in the evolution of a novel heat-sensitive channel. The future for understanding the molecular basis of sensory biology is promising, with great potential for comparative genomic analyses, studies on gene regulation and expression, exploration of the role of alternative splicing in the generation of proteomic diversity, and linking genetic mechanisms to

  12. The role of biology in planetary evolution: cyanobacterial primary production in low‐oxygen Proterozoic oceans

    OpenAIRE

    Hamilton, Trinity L.; Donald A Bryant; Macalady, Jennifer L.

    2015-01-01

    Summary Understanding the role of biology in planetary evolution remains an outstanding challenge to geobiologists. Progress towards unravelling this puzzle for Earth is hindered by the scarcity of well‐preserved rocks from the Archean (4.0 to 2.5 Gyr ago) and Proterozoic (2.5 to 0.5 Gyr ago) Eons. In addition, the microscopic life that dominated Earth's biota for most of its history left a poor fossil record, consisting primarily of lithified microbial mats, rare microbial body fossils and m...

  13. Controversy in Biology Classrooms—Citizen Science Approaches to Evolution and Applications to Climate Change Discussions

    Directory of Open Access Journals (Sweden)

    Rachel A. Yoho

    2015-11-01

    Full Text Available The biological sciences encompass topics considered controversial by the American public, such as evolution and climate change. We believe that the development of climate change education in the biology classroom is better informed by an understanding of the history of the teaching of evolution. A common goal for science educators should be to engender a greater respect for and appreciation of science among students while teaching specific content knowledge. Citizen science has emerged as a viable yet underdeveloped method for engaging students of all ages in key scientific issues that impact society through authentic data-driven scientific research. Where successful, citizen science may open avenues of communication and engagement with the scientific process that would otherwise be more difficult to achieve. Citizen science projects demonstrate versatility in education and the ability to test hypotheses by collecting large amounts of often publishable data. We find a great possibility for science education research in the incorporation of citizen science projects in curriculum, especially with respect to “hot topics” of socioscientific debate based on our review of the findings of other authors.

  14. Life’s a Gas: A Thermodynamic Theory of Biological Evolution

    Directory of Open Access Journals (Sweden)

    Keith R. Skene

    2015-07-01

    Full Text Available This paper outlines a thermodynamic theory of biological evolution. Beginning with a brief summary of the parallel histories of the modern evolutionary synthesis and thermodynamics, we use four physical laws and processes (the first and second laws of thermodynamics, diffusion and the maximum entropy production principle to frame the theory. Given that open systems such as ecosystems will move towards maximizing dispersal of energy, we expect biological diversity to increase towards a level, Dmax, representing maximum entropic production (Smax. Based on this theory, we develop a mathematical model to predict diversity over the last 500 million years. This model combines diversification, post-extinction recovery and likelihood of discovery of the fossil record. We compare the output of this model with that of the observed fossil record. The model predicts that life diffuses into available energetic space (ecospace towards a dynamic equilibrium, driven by increasing entropy within the genetic material. This dynamic equilibrium is punctured by extinction events, which are followed by restoration of Dmax through diffusion into available ecospace. Finally we compare and contrast our thermodynamic theory with the MES in relation to a number of important characteristics of evolution (progress, evolutionary tempo, form versus function, biosphere architecture, competition and fitness.

  15. Why Flavins Are not Competitors of Chlorophyll in the Evolution of Biological Converters of Solar Energy

    Science.gov (United States)

    Kritsky, Mikhail S.; Telegina, Taisiya A.; Vechtomova, Yulia L.; Buglak, Andrey A.

    2013-01-01

    Excited flavin molecules can photocatalyze reactions, leading to the accumulation of free energy in the products, and the data accumulated through biochemical experiments and by modeling prebiological processes suggest that flavins were available in the earliest stages of evolution. Furthermore, model experiments have shown that abiogenic flavin conjugated with a polyamino acid matrix, a pigment that photocatalyzes the phosphorylation of ADP to form ATP, could have been present in the prebiotic environment. Indeed, excited flavin molecules play key roles in many photoenzymes and regulatory photoreceptors, and the substantial structural differences between photoreceptor families indicate that evolution has repeatedly used flavins as chromophores for photoreceptor proteins. Some of these photoreceptors are equipped with a light-harvesting antenna, which transfers excitation energy to chemically reactive flavins in the reaction center. The sum of the available data suggests that evolution could have led to the formation of a flavin-based biological converter to convert light energy into energy in the form of ATP. PMID:23271372

  16. Why Flavins Are not Competitors of Chlorophyll in the Evolution of Biological Converters of Solar Energy

    Directory of Open Access Journals (Sweden)

    Mikhail S. Kritsky

    2012-12-01

    Full Text Available Excited flavin molecules can photocatalyze reactions, leading to the accumulation of free energy in the products, and the data accumulated through biochemical experiments and by modeling prebiological processes suggest that flavins were available in the earliest stages of evolution. Furthermore, model experiments have shown that abiogenic flavin conjugated with a polyamino acid matrix, a pigment that photocatalyzes the phosphorylation of ADP to form ATP, could have been present in the prebiotic environment. Indeed, excited flavin molecules play key roles in many photoenzymes and regulatory photoreceptors, and the substantial structural differences between photoreceptor families indicate that evolution has repeatedly used flavins as chromophores for photoreceptor proteins. Some of these photoreceptors are equipped with a light-harvesting antenna, which transfers excitation energy to chemically reactive flavins in the reaction center. The sum of the available data suggests that evolution could have led to the formation of a flavin-based biological converter to convert light energy into energy in the form of ATP.

  17. The biological evolution of conscience – from parent-offspring conflict to morality

    Directory of Open Access Journals (Sweden)

    Voland Eckart

    2014-12-01

    Full Text Available In this paper, two theories regarding the biological evolution of morality with conscience as its central regulatory agency are compared and contrasted. One theory (“navigator theory” interprets conscience as a strategically operating agency for the optimum balance between selfish and altruistic behavioral tendencies to maximize gains in cooperation in view of social complexity. From this standpoint, conscience serves the evolved self-interest of the person having a conscience. In contrast hereto, the second theory (“helper theory” locates the evolutionary origins of conscience on the battlefield of the parent- offspring conflict through intrafamilial demands for altruism. Functions of conscience, and thus human morality in a narrower sense, evolved during the transition of hominines to cooperative breeding and the novel helper conflict emerging through this evolution. The “helper theory” of the evolution of conscience can resolve some of the theoretical and empirical inconsistencies of the conventional “navigator theory”, in particular, the contradiction between the consequentialistic regulation of altruistic behavior and the non-consequentialistic nature of the judgment of conscience. And in contrast to the “navigator theory”, it is compatible with the observation that behavior guided by a conscience is not infrequently disastrous for one’s own fitness outcome.

  18. A hypothesis on the biological origins and social evolution of music and dance.

    Science.gov (United States)

    Wang, Tianyan

    2015-01-01

    The origins of music and musical emotions is still an enigma, here I propose a comprehensive hypothesis on the origins and evolution of music, dance, and speech from a biological and sociological perspective. I suggest that every pitch interval between neighboring notes in music represents corresponding movement pattern through interpreting the Doppler effect of sound, which not only provides a possible explanation for the transposition invariance of music, but also integrates music and dance into a common form-rhythmic movements. Accordingly, investigating the origins of music poses the question: why do humans appreciate rhythmic movements? I suggest that human appreciation of rhythmic movements and rhythmic events developed from the natural selection of organisms adapting to the internal and external rhythmic environments. The perception and production of, as well as synchronization with external and internal rhythms are so vital for an organism's survival and reproduction, that animals have a rhythm-related reward and emotion (RRRE) system. The RRRE system enables the appreciation of rhythmic movements and events, and is integral to the origination of music, dance and speech. The first type of rewards and emotions (rhythm-related rewards and emotions, RRREs) are evoked by music and dance, and have biological and social functions, which in turn, promote the evolution of music, dance and speech. These functions also evoke a second type of rewards and emotions, which I name society-related rewards and emotions (SRREs). The neural circuits of RRREs and SRREs develop in species formation and personal growth, with congenital and acquired characteristics, respectively, namely music is the combination of nature and culture. This hypothesis provides probable selection pressures and outlines the evolution of music, dance, and speech. The links between the Doppler effect and the RRREs and SRREs can be empirically tested, making the current hypothesis scientifically

  19. A hypothesis on the biological origins and social evolution of music and dance

    Directory of Open Access Journals (Sweden)

    Tianyan eWang

    2015-02-01

    Full Text Available The origins of music and musical emotions is still an enigma, here I propose a comprehensive hypothesis on the origins and evolution of music, dance and speech from a biological and sociological perspective. I suggest that every pitch interval between neighboring notes in music represents corresponding movement pattern through interpreting the Doppler effect of sound, which not only provides a possible explanation to the transposition invariance of music, but also integrates music and dance into a common form—rhythmic movements. Accordingly, investigating the origins of music poses the question: why do humans appreciate rhythmic movements? I suggest that human appreciation of rhythmic movements and rhythmic events developed from the natural selection of organisms adapting to the internal and external rhythmic environments. The perception and production of, as well as synchronization with external and internal rhythms are so vital for an organism’s survival and reproduction, that animals have a rhythm-related reward and emotion (RRRE system. The RRRE system enables the appreciation of rhythmic movements and events, and is integral to the origination of music, dance and speech. The first type of rewards and emotions (rhythm-related rewards and emotions, RRREs are evoked by music and dance, and have biological and social functions, which in turn, promote the evolution of music, dance and speech. These functions also evoke a second type of rewards and emotions, which I name society-related rewards and emotions (SRREs. The neural circuits of RRREs and SRREs develop in species formation and personal growth, with congenital and acquired characteristics, respectively, namely music is the combination of nature and culture. This hypothesis provides probable selection pressures and outlines the evolution of music, dance and speech. The links between the Doppler effect and the RRREs and SRREs can be empirically tested, making the current hypothesis

  20. High school biology evolution learning experiences in a rural context: a case of and for cultural border crossing

    Science.gov (United States)

    Borgerding, Lisa A.

    2016-12-01

    Although the concept of "rural" is difficult to define, rural science education provides the possibility for learning centered upon a strong connection to the local community. Rural American adolescents tend to be more religious than their urban counterparts and less accepting of evolution than their non-rural peers. Because the status and perception of evolutionary theory may be very different within the students' lifeworlds and the subcultures of the science classroom and science itself, a cultural border crossing metaphor can be applied to evolution teaching and learning. This study examines how a teacher may serve as a cultural border crossing tour guide for students at a rural high school as they explore the concept of biological evolution in their high school biology class. Data collection entailed two formal teacher interviews, field note observations of two biology class periods each day for 16 days during the Evolution unit, individual interviews with 14 students, student evolution acceptance surveys, student evolution content tests, and classroom artifacts. The major findings center upon three themes regarding how this teacher and these students had largely positive evolution learning experiences even as some students continued to reject evolution. First, the teacher strategically positioned himself in two ways: using his unique "local" trusted position in the community and school and taking a position in which he did not personally represent science by instead consistently teaching evolution "according to scientists." Second, his instruction honored local "rural" funds of knowledge with respect to local knowledge of nature and by treating students' religious knowledge as a form of local expertise about one set of answers to questions also addressed by evolution. Third, the teacher served as a border crossing "tour guide" by helping students identify how the culture of science and the culture of their lifeworlds may differ with respect to evolutionary

  1. Evolution and personal religious belief: Christian biology-related majors' search for reconciliation at a Christian university

    Science.gov (United States)

    Winslow, Mark William

    The goal of this study was to explore how Christian biology-related majors at a Christian university perceive the apparent conflicts between their understanding of evolution and their religious beliefs, and how their faith, as a structural-developmental system for ordering and making meaning of the world, plays a role in the mediating process. This naturalistic study utilized a case study design of 15 participants specified as undergraduate biology-related majors or recent biology-related graduates from a midwestern Christian university who had completed an upper-level course on evolution. Data were collected through semi-structured interviews that investigated participants' faith and their views on creationism and evolution. Fowler's theory of faith development and Parks' model of college students' faith was extensively used. Additional data were collected through an Evolution Attitudes Survey and a position paper on evolution as an assignment in the evolution course. Data analysis revealed patterns that were organized into themes and sub-themes that were the major outcomes of the study. Most participants were raised to believe in creationism, but came to accept evolution through an extended process of evaluating the scientific evidence in support of evolution, negotiating the literalness of Genesis, recognizing evolution as a non-salvation issue, and observing professors as role models of Christians who accept evolution. Participants remained committed to their personal religious beliefs despite apprehension that accompanied the reconciliation process in accepting evolution. Most participants operated from the perspective that science and religion are separate and interacting domains. Faith played an important role in how participants reconciled their understanding of evolution and their personal religious beliefs. Participants who operated in conventional faith dismissed contentious issues or collapsed dichotomies in an effort to avoid ambiguity and perceived

  2. High school biology evolution learning experiences in a rural context: a case of and for cultural border crossing

    Science.gov (United States)

    Borgerding, Lisa A.

    2017-03-01

    Although the concept of "rural" is difficult to define, rural science education provides the possibility for learning centered upon a strong connection to the local community. Rural American adolescents tend to be more religious than their urban counterparts and less accepting of evolution than their non-rural peers. Because the status and perception of evolutionary theory may be very different within the students' lifeworlds and the subcultures of the science classroom and science itself, a cultural border crossing metaphor can be applied to evolution teaching and learning. This study examines how a teacher may serve as a cultural border crossing tour guide for students at a rural high school as they explore the concept of biological evolution in their high school biology class. Data collection entailed two formal teacher interviews, field note observations of two biology class periods each day for 16 days during the Evolution unit, individual interviews with 14 students, student evolution acceptance surveys, student evolution content tests, and classroom artifacts. The major findings center upon three themes regarding how this teacher and these students had largely positive evolution learning experiences even as some students continued to reject evolution. First, the teacher strategically positioned himself in two ways: using his unique "local" trusted position in the community and school and taking a position in which he did not personally represent science by instead consistently teaching evolution "according to scientists." Second, his instruction honored local "rural" funds of knowledge with respect to local knowledge of nature and by treating students' religious knowledge as a form of local expertise about one set of answers to questions also addressed by evolution. Third, the teacher served as a border crossing "tour guide" by helping students identify how the culture of science and the culture of their lifeworlds may differ with respect to evolutionary

  3. The role of biology in planetary evolution: cyanobacterial primary production in low-oxygen Proterozoic oceans.

    Science.gov (United States)

    Hamilton, Trinity L; Bryant, Donald A; Macalady, Jennifer L

    2016-02-01

    Understanding the role of biology in planetary evolution remains an outstanding challenge to geobiologists. Progress towards unravelling this puzzle for Earth is hindered by the scarcity of well-preserved rocks from the Archean (4.0 to 2.5 Gyr ago) and Proterozoic (2.5 to 0.5 Gyr ago) Eons. In addition, the microscopic life that dominated Earth's biota for most of its history left a poor fossil record, consisting primarily of lithified microbial mats, rare microbial body fossils and membrane-derived hydrocarbon molecules that are still challenging to interpret. However, it is clear from the sulfur isotope record and other geochemical proxies that the production of oxygen or oxidizing power radically changed Earth's surface and atmosphere during the Proterozoic Eon, pushing it away from the more reducing conditions prevalent during the Archean. In addition to ancient rocks, our reconstruction of Earth's redox evolution is informed by our knowledge of biogeochemical cycles catalysed by extant biota. The emergence of oxygenic photosynthesis in ancient cyanobacteria represents one of the most impressive microbial innovations in Earth's history, and oxygenic photosynthesis is the largest source of O2 in the atmosphere today. Thus the study of microbial metabolisms and evolution provides an important link between extant biota and the clues from the geologic record. Here, we consider the physiology of cyanobacteria (the only microorganisms capable of oxygenic photosynthesis), their co-occurrence with anoxygenic phototrophs in a variety of environments and their persistence in low-oxygen environments, including in water columns as well as mats, throughout much of Earth's history. We examine insights gained from both the rock record and cyanobacteria presently living in early Earth analogue ecosystems and synthesize current knowledge of these ancient microbial mediators in planetary redox evolution. Our analysis supports the hypothesis that anoxygenic photosynthesis

  4. The role of biology in planetary evolution: cyanobacterial primary production in low‐oxygen Proterozoic oceans

    Science.gov (United States)

    Bryant, Donald A.; Macalady, Jennifer L.

    2016-01-01

    Summary Understanding the role of biology in planetary evolution remains an outstanding challenge to geobiologists. Progress towards unravelling this puzzle for Earth is hindered by the scarcity of well‐preserved rocks from the Archean (4.0 to 2.5 Gyr ago) and Proterozoic (2.5 to 0.5 Gyr ago) Eons. In addition, the microscopic life that dominated Earth's biota for most of its history left a poor fossil record, consisting primarily of lithified microbial mats, rare microbial body fossils and membrane‐derived hydrocarbon molecules that are still challenging to interpret. However, it is clear from the sulfur isotope record and other geochemical proxies that the production of oxygen or oxidizing power radically changed Earth's surface and atmosphere during the Proterozoic Eon, pushing it away from the more reducing conditions prevalent during the Archean. In addition to ancient rocks, our reconstruction of Earth's redox evolution is informed by our knowledge of biogeochemical cycles catalysed by extant biota. The emergence of oxygenic photosynthesis in ancient cyanobacteria represents one of the most impressive microbial innovations in Earth's history, and oxygenic photosynthesis is the largest source of O 2 in the atmosphere today. Thus the study of microbial metabolisms and evolution provides an important link between extant biota and the clues from the geologic record. Here, we consider the physiology of cyanobacteria (the only microorganisms capable of oxygenic photosynthesis), their co‐occurrence with anoxygenic phototrophs in a variety of environments and their persistence in low‐oxygen environments, including in water columns as well as mats, throughout much of Earth's history. We examine insights gained from both the rock record and cyanobacteria presently living in early Earth analogue ecosystems and synthesize current knowledge of these ancient microbial mediators in planetary redox evolution. Our analysis supports the hypothesis that anoxygenic

  5. Archival Collections are Important in the Study of the Biology, Diversity, and Evolution of Arboviruses

    Science.gov (United States)

    Pyke, Alyssa T.; Warrilow, David

    2016-01-01

    Historically, classifications of arboviruses were based on serological techniques. Hence, collections of arbovirus isolates have been central to this process by providing the antigenic reagents for these methods. However, with increasing concern about biosafety and security, the introduction of molecular biology techniques has led to greater emphasis on the storage of nucleic acid sequence data over the maintenance of archival material. In this commentary, we provide examples of where archival collections provide an important source of genetic material to assist in confirming the authenticity of reference strains and vaccine stocks, to clarify taxonomic relationships particularly when isolates of the same virus species have been collected across a wide expanse of time and space, for future phenotypic analysis, to determine the historical diversity of strains, and to understand the mechanisms leading to changes in genome structure and virus evolution. PMID:27688704

  6. Neocortex expansion in development and evolution - from cell biology to single genes.

    Science.gov (United States)

    Wilsch-Bräuninger, Michaela; Florio, Marta; Huttner, Wieland B

    2016-08-01

    Neocortex expansion in development and evolution reflects an increased and prolonged activity of neural progenitor cells. Insight into key aspects of the underlying cell biology has recently been obtained. First, the restriction of apical progenitors to undergo mitosis at the ventricular surface is overcome by generation of basal progenitors, which are free to undergo mitosis at abventricular location, typically the subventricular zone. This process involves basolateral ciliogenesis, delamination from the apical adherens junction belt, and loss of apical cell polarity. Second, proliferative capacity of basal progenitors is supported by self-produced extracellular matrix constituents, which in turn promote growth factor signalling. Humans amplify these processes by characteristic alterations in expression of key regulatory genes (PAX6), and via human-specific genes (ARHGAP11B).

  7. A non-linear irreversible thermodynamic perspective on organic pigment proliferation and biological evolution

    CERN Document Server

    Michaelian, Karo

    2013-01-01

    The most important thermodynamic work performed by life today is the dissipation of the solar photon flux into heat through organic pigments in water. From this thermodynamic perspective, biological evolution is thus just the dispersal of organic pigments and water throughout Earth's surface, while adjusting the gases of Earth's atmosphere to allow the most intense part of the solar spectrum to penetrate the atmosphere and reach the surface to be intercepted by these pigments. The covalent bonding of atoms in organic pigments provides excited levels compatible with the energies of these photons. Internal conversion through vibrational relaxation to the ground state of these excited molecules when in water leads to rapid dissipation of the solar photons into heat, and this is the major source of entropy production on Earth. A non-linear irreversible thermodynamic analysis shows that the proliferation of organic pigments on Earth is a direct consequence of the pigments catalytic properties in dissipating the so...

  8. Archival Collections are Important in the Study of the Biology, Diversity, and Evolution of Arboviruses.

    Science.gov (United States)

    Pyke, Alyssa T; Warrilow, David

    2016-01-01

    Historically, classifications of arboviruses were based on serological techniques. Hence, collections of arbovirus isolates have been central to this process by providing the antigenic reagents for these methods. However, with increasing concern about biosafety and security, the introduction of molecular biology techniques has led to greater emphasis on the storage of nucleic acid sequence data over the maintenance of archival material. In this commentary, we provide examples of where archival collections provide an important source of genetic material to assist in confirming the authenticity of reference strains and vaccine stocks, to clarify taxonomic relationships particularly when isolates of the same virus species have been collected across a wide expanse of time and space, for future phenotypic analysis, to determine the historical diversity of strains, and to understand the mechanisms leading to changes in genome structure and virus evolution.

  9. A spectre haunts evolution: Haeckel, Heidegger, and the all-too-human history of biology.

    Science.gov (United States)

    Day, Matthew

    2010-01-01

    Since The Meaning of Evolution (1992), Robert J. Richards has argued that modern evolutionary theory is rooted in late 18th-century Romantic science. The publication of The Tragic Sense of Life (2009) provides a fitting occasion to evaluate how this perspective revises the standard history of biological thought. This essay focuses on three aspects of Richards's attempt to rehabilitate the reputation of German Naturphilosophie: (1) the identification of Romantic strains in Charles Darwin's portrait of evolutionary history; (2) the demonstration that any attempt to treat Ernst Haeckel as a "pseudo-Darwinian" inevitably renders Darwin himself a "pseudo-Darwinian"; and (3) the denial of Haeckel's alleged responsibility for the rise of Nazi racial hygiene. This article examines Richards's case for clearing Haeckel's name, as well as the subsequent (slanderous) charge from Daniel Gasman that Richards is guilty of whitewashing the Haeckelian roots of the Holocaust.

  10. Design in nature how the constructal law governs evolution in biology, physics, technology, and social organization

    CERN Document Server

    Bejan, Adrian

    2013-01-01

    In this groundbreaking book, Adrian Bejan takes the recurring patterns in nature—trees, tributaries, air passages, neural networks, and lightning bolts—and reveals how a single principle of physics, the constructal law, accounts for the evolution of these and many other designs in our world. Everything—from biological life to inanimate systems—generates shape and structure and evolves in a sequence of ever-improving designs in order to facilitate flow. River basins, cardiovascular systems, and bolts of lightning are very efficient flow systems to move a current—of water, blood, or electricity. Likewise, the more complex architecture of animals evolve to cover greater distance per unit of useful energy, or increase their flow across the land. Such designs also appear in human organizations, like the hierarchical “flowcharts” or reporting structures in corporations and political bodies. All are governed by the same principle, known as the constructal law, and configure and reconfigure themselves...

  11. Hydrogen, metals, bifurcating electrons, and proton gradients: the early evolution of biological energy conservation.

    Science.gov (United States)

    Martin, William F

    2012-03-09

    Life is a persistent, self-specified set of far from equilibrium chemical reactions. In modern microbes, core carbon and energy metabolism are what keep cells alive. In very early chemical evolution, the forerunners of carbon and energy metabolism were the processes of generating reduced carbon compounds from CO(2) and the mechanisms of harnessing energy as compounds capable of doing some chemical work. The process of serpentinization at alkaline hydrothermal vents holds promise as a model for the origin of early reducing power, because Fe(2+) in the Earth's crust reduces water to H(2) and inorganic carbon to methane. The overall geochemical process of serpentinization is similar to the biochemical process of methanogenesis, and methanogenesis is similar to acetogenesis in that both physiologies allow energy conservation from the reduction of CO(2) with electrons from H(2). Electron bifurcation is a newly recognized cytosolic process that anaerobes use generate low potential electrons, it plays an important role in some forms of methanogenesis and, via speculation, possibly in acetogenesis. Electron bifurcation likely figures into the early evolution of biological energy conservation.

  12. The Towuti Drilling Project: paleoenvironments, biological evolution, and geomicrobiology of a tropical Pacific lake

    Science.gov (United States)

    Russell, James M.; Bijaksana, Satria; Vogel, Hendrik; Melles, Martin; Kallmeyer, Jens; Ariztegui, Daniel; Crowe, Sean; Fajar, Silvia; Hafidz, Abdul; Haffner, Doug; Hasberg, Ascelina; Ivory, Sarah; Kelly, Christopher; King, John; Kirana, Kartika; Morlock, Marina; Noren, Anders; O'Grady, Ryan; Ordonez, Luis; Stevenson, Janelle; von Rintelen, Thomas; Vuillemin, Aurele; Watkinson, Ian; Wattrus, Nigel; Wicaksono, Satrio; Wonik, Thomas; Bauer, Kohen; Deino, Alan; Friese, André; Henny, Cynthia; Imran; Marwoto, Ristiyanti; Ode Ngkoimani, La; Nomosatryo, Sulung; Ode Safiuddin, La; Simister, Rachel; Tamuntuan, Gerald

    2016-07-01

    The Towuti Drilling Project (TDP) is an international research program, whose goal is to understand long-term environmental and climatic change in the tropical western Pacific, the impacts of geological and environmental changes on the biological evolution of aquatic taxa, and the geomicrobiology and biogeochemistry of metal-rich, ultramafic-hosted lake sediments through the scientific drilling of Lake Towuti, southern Sulawesi, Indonesia. Lake Towuti is a large tectonic lake at the downstream end of the Malili lake system, a chain of five highly biodiverse lakes that are among the oldest lakes in Southeast Asia. In 2015 we carried out a scientific drilling program on Lake Towuti using the International Continental Scientific Drilling Program (ICDP) Deep Lakes Drilling System (DLDS). We recovered a total of ˜ 1018 m of core from 11 drilling sites with water depths ranging from 156 to 200 m. Recovery averaged 91.7 %, and the maximum drilling depth was 175 m below the lake floor, penetrating the entire sedimentary infill of the basin. Initial data from core and borehole logging indicate that these cores record the evolution of a highly dynamic tectonic and limnological system, with clear indications of orbital-scale climate variability during the mid- to late Pleistocene.

  13. The common extremalities in biology and physics maximum energy dissipation principle in chemistry, biology, physics and evolution

    CERN Document Server

    Moroz, Adam

    2011-01-01

    This book is the first unified systemic description of dissipative phenomena, taking place in biology, and non-dissipative (conservative) phenomena, which is more relevant to physics. Fully updated and revised, this new edition extends our understanding of nonlinear phenomena in biology and physics from the extreme / optimal perspective. The first book to provide understanding of physical phenomena from a biological perspective and biological phenomena from a physical perspectiveDiscusses emerging fields and analysisProvides examples

  14. Anticipatory dynamics of biological systems: from molecular quantum states to evolution

    Science.gov (United States)

    Igamberdiev, Abir U.

    2015-08-01

    Living systems possess anticipatory behaviour that is based on the flexibility of internal models generated by the system's embedded description. The idea was suggested by Aristotle and is explicitly introduced to theoretical biology by Rosen. The possibility of holding the embedded internal model is grounded in the principle of stable non-equilibrium (Bauer). From the quantum mechanical view, this principle aims to minimize energy dissipation in expense of long relaxation times. The ideas of stable non-equilibrium were developed by Liberman who viewed living systems as subdivided into the quantum regulator and the molecular computer supporting coherence of the regulator's internal quantum state. The computational power of the cell molecular computer is based on the possibility of molecular rearrangements according to molecular addresses. In evolution, the anticipatory strategies are realized both as a precession of phylogenesis by ontogenesis (Berg) and as the anticipatory search of genetic fixation of adaptive changes that incorporates them into the internal model of genetic system. We discuss how the fundamental ideas of anticipation can be introduced into the basic foundations of theoretical biology.

  15. Theory of interface: category theory, directed networks and evolution of biological networks.

    Science.gov (United States)

    Haruna, Taichi

    2013-11-01

    Biological networks have two modes. The first mode is static: a network is a passage on which something flows. The second mode is dynamic: a network is a pattern constructed by gluing functions of entities constituting the network. In this paper, first we discuss that these two modes can be associated with the category theoretic duality (adjunction) and derive a natural network structure (a path notion) for each mode by appealing to the category theoretic universality. The path notion corresponding to the static mode is just the usual directed path. The path notion for the dynamic mode is called lateral path which is the alternating path considered on the set of arcs. Their general functionalities in a network are transport and coherence, respectively. Second, we introduce a betweenness centrality of arcs for each mode and see how the two modes are embedded in various real biological network data. We find that there is a trade-off relationship between the two centralities: if the value of one is large then the value of the other is small. This can be seen as a kind of division of labor in a network into transport on the network and coherence of the network. Finally, we propose an optimization model of networks based on a quality function involving intensities of the two modes in order to see how networks with the above trade-off relationship can emerge through evolution. We show that the trade-off relationship can be observed in the evolved networks only when the dynamic mode is dominant in the quality function by numerical simulations. We also show that the evolved networks have features qualitatively similar to real biological networks by standard complex network analysis.

  16. Three Decades of Anti-Evolution Campaign and Its Results: Turkish Undergraduates' Acceptance and Understanding of the Biological Evolution Theory

    Science.gov (United States)

    Peker, Deniz; Comert, Gulsum Gul; Kence, Aykut

    2010-01-01

    Even though in the early years of the Republic of Turkey Darwin's theory of evolution was treated as a scientific theory and taught fairly in schools, despite all the substantial evidence accumulated supporting the theory of evolution since then, Darwin and his ideas today have been scorned by curriculum and education policy makers. Furthermore,…

  17. A Comparison of Massachusetts and Texas High School Biology Teachers' Attitudes towards the Teaching of Evolution

    Science.gov (United States)

    Howarth, Richard T.

    2012-01-01

    Darwin's theory of evolution by natural selection is considered to be the unifying theory for all life sciences (American Association for the Advancement of Science, AAAS, 1990; National Academy of Sciences, 1998; National Research Council, NRC, 1996; National Science Teachers Association, NSTA, 2010a) and as such, the biology topic has been…

  18. Recent advances in alveolar biology: evolution and function of alveolar proteins.

    Science.gov (United States)

    Orgeig, Sandra; Hiemstra, Pieter S; Veldhuizen, Edwin J A; Casals, Cristina; Clark, Howard W; Haczku, Angela; Knudsen, Lars; Possmayer, Fred

    2010-08-31

    This review is focused on the evolution and function of alveolar proteins. The lung faces physical and environmental challenges, due to changing pressures/volumes and foreign pathogens, respectively. The pulmonary surfactant system is integral in protecting the lung from these challenges via two groups of surfactant proteins - the small molecular weight hydrophobic SPs, SP-B and -C, that regulate interfacial adsorption of the lipids, and the large hydrophilic SPs, SP-A and -D, which are surfactant collectins capable of inhibiting foreign pathogens. Further aiding pulmonary host defence are non-surfactant collectins and antimicrobial peptides that are expressed across the biological kingdoms. Linking to the first symposium session, which emphasised molecular structure and biophysical function of surfactant lipids and proteins, this review begins with a discussion of the role of temperature and hydrostatic pressure in shaping the evolution of SP-C in mammals. Transitioning to the role of the alveolus in innate host defence we discuss the structure, function and regulation of antimicrobial peptides, the defensins and cathelicidins. We describe the recent discovery of novel avian collectins and provide evidence for their role in preventing influenza infection. This is followed by discussions of the roles of SP-A and SP-D in mediating host defence at the alveolar surface and in mediating inflammation and the allergic response of the airways. Finally we discuss the use of animal models of lung disease including knockouts to develop an understanding of the role of these proteins in initiating and/or perpetuating disease with the aim of developing new therapeutic strategies.

  19. Once upon Multivariate Analyses: When They Tell Several Stories about Biological Evolution.

    Science.gov (United States)

    Renaud, Sabrina; Dufour, Anne-Béatrice; Hardouin, Emilie A; Ledevin, Ronan; Auffray, Jean-Christophe

    2015-01-01

    Geometric morphometrics aims to characterize of the geometry of complex traits. It is therefore by essence multivariate. The most popular methods to investigate patterns of differentiation in this context are (1) the Principal Component Analysis (PCA), which is an eigenvalue decomposition of the total variance-covariance matrix among all specimens; (2) the Canonical Variate Analysis (CVA, a.k.a. linear discriminant analysis (LDA) for more than two groups), which aims at separating the groups by maximizing the between-group to within-group variance ratio; (3) the between-group PCA (bgPCA) which investigates patterns of between-group variation, without standardizing by the within-group variance. Standardizing within-group variance, as performed in the CVA, distorts the relationships among groups, an effect that is particularly strong if the variance is similarly oriented in a comparable way in all groups. Such shared direction of main morphological variance may occur and have a biological meaning, for instance corresponding to the most frequent standing genetic variation in a population. Here we undertake a case study of the evolution of house mouse molar shape across various islands, based on the real dataset and simulations. We investigated how patterns of main variance influence the depiction of among-group differentiation according to the interpretation of the PCA, bgPCA and CVA. Without arguing about a method performing 'better' than another, it rather emerges that working on the total or between-group variance (PCA and bgPCA) will tend to put the focus on the role of direction of main variance as line of least resistance to evolution. Standardizing by the within-group variance (CVA), by dampening the expression of this line of least resistance, has the potential to reveal other relevant patterns of differentiation that may otherwise be blurred.

  20. An Aristotelian Account of Evolution and the Contemporary Philosophy of Biology

    Directory of Open Access Journals (Sweden)

    Mariusz Tabaczek

    2015-05-01

    Full Text Available The anti-reductionist character of the recent philosophy of biology and the dynamic development of the science of emergent properties prove that the time is ripe to reintroduce the thought of Aristotle, the first advocate of a “top-down” approach in life-sciences, back into the science/philosophy debate. His philosophy of nature provides profound insights particularly in the context of the contemporary science of evolution, which is still struggling with the questions of form (species, teleology, and the role of chance in evolutionary processes. However, although Aristotle is referenced in the evolutionary debate, a thorough analysis of his theory of hylomorphism and the classical principle of causality which he proposes is still needed in this exchange. Such is the main concern of the first part of the present article which shows Aristotle’s metaphysics of substance as an open system, ready to incorporate new hypothesis of modern and contemporary science. The second part begins with the historical exploration of the trajectory from Darwin to Darwinism regarded as a metaphysical position. This exploration leads to an inquiry into the central topics of the present debate in the philosophy of evolutionary biology. It shows that Aristotle’s understanding of species, teleology, and chance – in the context of his fourfold notion of causality – has a considerable explanatory power which may enhance our understanding of the nature of evolutionary processes. This fact may inspire, in turn, a retrieval of the classical theology of divine action, based on Aristotelian metaphysics, in the science/theology dialogue. The aim of the present article is to prepare a philosophical ground for such project.

  1. The biological evolution of guilt, shame and anxiety: A new theory of negative legacy emotions.

    Science.gov (United States)

    Breggin, Peter R

    2015-07-01

    Human beings are the most social and the most violent creatures on Earth. The combination of cooperation and aggression enabled us to dominate our ecosystem. However, the existence of violent impulses would have made it difficult or impossible for humans to live in close-knit families and clans without destroying each other. Nature's answer was the development of guilt, shame and anxiety-internal emotional inhibitions or restraints specifically against aggressive self-assertion within the family and other close relationships. The theory of negative legacy emotions proposes the first unitary concept for the biopsychosocial function of guilt, shame and anxiety, and seeks their origin in biological evolution and natural selection. Natural selection favored individuals with built-in emotional restraints that reduced conflicts within their family and tribal unit, optimizing their capacity to survive and reproduce within the protection of their small, intimate societies, while maintaining their capacity for violence against outsiders. Unfortunately, these negative legacy emotions are rudimentary and often ineffective in their psychosocial and developmental function. As a result, they produce many unintended untoward effects, including the frequent breakdown of restraints in the family and the uninhibited unleashing of violence against outsiders.

  2. The virtue of innovation: innovation through the lenses of biological evolution.

    Science.gov (United States)

    Kell, Douglas B; Lurie-Luke, Elena

    2015-02-06

    We rehearse the processes of innovation and discovery in general terms, using as our main metaphor the biological concept of an evolutionary fitness landscape. Incremental and disruptive innovations are seen, respectively, as successful searches carried out locally or more widely. They may also be understood as reflecting evolution by mutation (incremental) versus recombination (disruptive). We also bring a platonic view, focusing on virtue and memory. We use 'virtue' as a measure of efforts, including the knowledge required to come up with disruptive and incremental innovations, and 'memory' as a measure of their lifespan, i.e. how long they are remembered. Fostering innovation, in the evolutionary metaphor, means providing the wherewithal to promote novelty, good objective functions that one is trying to optimize, and means to improve one's knowledge of, and ability to navigate, the landscape one is searching. Recombination necessarily implies multi- or inter-disciplinarity. These principles are generic to all kinds of creativity, novel ideas formation and the development of new products and technologies.

  3. Evolution of epithelial morphogenesis: phenotypic integration across multiple levels of biological organization

    Directory of Open Access Journals (Sweden)

    Thorsten eHorn

    2015-09-01

    Full Text Available Morphogenesis involves the dynamic reorganization of cell and tissue shapes to create the three-dimensional body. Intriguingly, different species have evolved different morphogenetic processes to achieve the same general outcomes during embryonic development. How are meaningful comparisons between species made, and where do the differences lie? In this Perspective, we argue that examining the evolution of embryonic morphogenesis requires the simultaneous consideration of different levels of biological organization: (1 genes, (2 cells, (3 tissues, and (4 the entire egg. To illustrate the importance of integrating these levels, we use the extraembryonic epithelia of insects – a lineage-specific innovation and evolutionary hotspot – as an exemplary case study. We discuss how recent functional data, primarily from RNAi experiments targeting the Hox3/ Zen and U-shaped group transcription factors, provide insights into developmental processes at all four levels. Comparisons of these data from several species both challenge and inform our understanding of homology, in assessing how the process of epithelial morphogenesis has itself evolved.

  4. Recasting developmental evolution in terms of genetic pathway and network evolution ... and the implications for comparative biology.

    Science.gov (United States)

    Wilkins, Adam S

    2005-09-15

    The morphological features of complex organisms are the outcomes of developmental processes. Developmental processes, in turn, reflect the genetic networks that underlie them. Differences in morphology must ultimately, therefore, reflect differences in the underlying genetic networks. A mutation that affects a developmental process does so by affecting either a gene whose product acts as an upstream controlling element, an intermediary connecting link, or as a downstream output of the network that governs the trait's development. Although the immense diversity of gene networks in the animal and plant kingdoms would seem to preclude any general "rules" of network evolution, the material discussed here suggests that the patterns of genetic pathway and network evolution actually fall into a number of discrete modes. The potential utility of this conceptual framework in reconstructing instances of developmental evolution and for comparative neurobiology will be discussed.

  5. Jupiter and Planet Earth. [planetary and biological evolution and natural satellites

    Science.gov (United States)

    1975-01-01

    The evolution of Jupiter and Earth are discussed along with their atmospheres, the radiation belts around both planets, natural satellites, the evolution of life, and the Pioneer 10. Educational study projects are also included.

  6. Nothing in Evolution Makes Sense Except in the Light of Genomics: Read-Write Genome Evolution as an Active Biological Process.

    Science.gov (United States)

    Shapiro, James A

    2016-06-08

    The 21st century genomics-based analysis of evolutionary variation reveals a number of novel features impossible to predict when Dobzhansky and other evolutionary biologists formulated the neo-Darwinian Modern Synthesis in the middle of the last century. These include three distinct realms of cell evolution; symbiogenetic fusions forming eukaryotic cells with multiple genome compartments; horizontal organelle, virus and DNA transfers; functional organization of proteins as systems of interacting domains subject to rapid evolution by exon shuffling and exonization; distributed genome networks integrated by mobile repetitive regulatory signals; and regulation of multicellular development by non-coding lncRNAs containing repetitive sequence components. Rather than single gene traits, all phenotypes involve coordinated activity by multiple interacting cell molecules. Genomes contain abundant and functional repetitive components in addition to the unique coding sequences envisaged in the early days of molecular biology. Combinatorial coding, plus the biochemical abilities cells possess to rearrange DNA molecules, constitute a powerful toolbox for adaptive genome rewriting. That is, cells possess "Read-Write Genomes" they alter by numerous biochemical processes capable of rapidly restructuring cellular DNA molecules. Rather than viewing genome evolution as a series of accidental modifications, we can now study it as a complex biological process of active self-modification.

  7. Nothing in Evolution Makes Sense Except in the Light of Genomics: Read–Write Genome Evolution as an Active Biological Process

    Directory of Open Access Journals (Sweden)

    James A. Shapiro

    2016-06-01

    Full Text Available The 21st century genomics-based analysis of evolutionary variation reveals a number of novel features impossible to predict when Dobzhansky and other evolutionary biologists formulated the neo-Darwinian Modern Synthesis in the middle of the last century. These include three distinct realms of cell evolution; symbiogenetic fusions forming eukaryotic cells with multiple genome compartments; horizontal organelle, virus and DNA transfers; functional organization of proteins as systems of interacting domains subject to rapid evolution by exon shuffling and exonization; distributed genome networks integrated by mobile repetitive regulatory signals; and regulation of multicellular development by non-coding lncRNAs containing repetitive sequence components. Rather than single gene traits, all phenotypes involve coordinated activity by multiple interacting cell molecules. Genomes contain abundant and functional repetitive components in addition to the unique coding sequences envisaged in the early days of molecular biology. Combinatorial coding, plus the biochemical abilities cells possess to rearrange DNA molecules, constitute a powerful toolbox for adaptive genome rewriting. That is, cells possess “Read–Write Genomes” they alter by numerous biochemical processes capable of rapidly restructuring cellular DNA molecules. Rather than viewing genome evolution as a series of accidental modifications, we can now study it as a complex biological process of active self-modification.

  8. The Coverage of Human Evolution in High School Biology Textbooks in the 20th Century and in Current State Science Standards

    Science.gov (United States)

    Skoog, Gerald

    Efforts to eliminate or neutralize the coverage of evolution in high school biology textbooks in the United States have persisted with varying degrees of intensity and success since the 1920s. In particular, the coverage of human evolution has been impacted by these efforts. Evidence of the success of these efforts can be chronicled by the emphasis given to human evolution in secondary biology textbooks historically and in the current state science standards. Prior to the 1960s, biology textbooks provided little emphasis to human evolution. In the 1970s and early 1980s textbooks reduced the coverage of human evolution. However, in the 1990s the coverage became quite comprehensive again. In 2004, the state science frameworks of only three states had standards concerned with human evolution.

  9. Structural calibration of the rates of amino acid evolution in a search for Darwin in drifting biological systems.

    Science.gov (United States)

    Toft, Christina; Fares, Mario A

    2010-10-01

    In the last two decades, many reports of proteins under positive selection have brought the neutral theory into question. However, the methods used to detect selection have ignored the evolvability of amino acids within proteins, which is fundamental to distinguishing positive selection from the relaxed constraints caused by genetic drift. Disentangling these two counterbalancing forces is essential to test the neutral theory. Here, we calibrate rates of amino acid divergence by using structural information from the full set of crystallized proteins in bacteria. In agreement with previous reports, we show that rates of amino acid evolution correlate negatively with the number of per-amino acid atomic interactions. Calibration of the rates of evolution allows identifying signatures of selection in biological systems that evolve under strong genetic drift, such as endosymbiotic bacteria. Application of this method identifies different rates and dynamics of evolution for highly connected amino acids in the structure compared with sparsely connected ones. We also unearth patterns of Darwinian selection in fundamental cellular proteins in endosymbiotic bacteria including the cochaperonin GroES, ribosomal proteins, proteins involved in cell cycle control, DNA-binding proteins, and proteins involved in DNA replication and repair. This is, to our knowledge, the first attempt to distinguish adaptive evolution from relaxed constraints in biological systems under genetic drift.

  10. Stochastic many-body problems in ecology, evolution, neuroscience, and systems biology

    Science.gov (United States)

    Butler, Thomas C.

    Using the tools of many-body theory, I analyze problems in four different areas of biology dominated by strong fluctuations: The evolutionary history of the genetic code, spatiotemporal pattern formation in ecology, spatiotemporal pattern formation in neuroscience and the robustness of a model circadian rhythm circuit in systems biology. In the first two research chapters, I demonstrate that the genetic code is extremely optimal (in the sense that it manages the effects of point mutations or mistranslations efficiently), more than an order of magnitude beyond what was previously thought. I further show that the structure of the genetic code implies that early proteins were probably only loosely defined. Both the nature of early proteins and the extreme optimality of the genetic code are interpreted in light of recent theory [1] as evidence that the evolution of the genetic code was driven by evolutionary dynamics that were dominated by horizontal gene transfer. I then explore the optimality of a proposed precursor to the genetic code. The results show that the precursor code has only limited optimality, which is interpreted as evidence that the precursor emerged prior to translation, or else never existed. In the next part of the dissertation, I introduce a many-body formalism for reaction-diffusion systems described at the mesoscopic scale with master equations. I first apply this formalism to spatially-extended predator-prey ecosystems, resulting in the prediction that many-body correlations and fluctuations drive population cycles in time, called quasicycles. Most of these results were previously known, but were derived using the system size expansion [2, 3]. I next apply the analytical techniques developed in the study of quasi-cycles to a simple model of Turing patterns in a predator-prey ecosystem. This analysis shows that fluctuations drive the formation of a new kind of spatiotemporal pattern formation that I name "quasi-patterns." These quasi

  11. 50 Years of JBE: The Evolution of Biology as a School Subject

    Science.gov (United States)

    Jenkins, Edgar

    2016-01-01

    When the "Journal of Biological Education" was first published in 1967, biology was still very much the Cinderella of the three school sciences in many countries. Most selective secondary school biology courses readily betrayed their origins as an unconvincing coalition of botany and zoology. In the non-selective secondary modern…

  12. Cold Spring Harbor symposia on quantitative biology: Volume 52, Evolution of catalytic function

    Energy Technology Data Exchange (ETDEWEB)

    1987-01-01

    This document contains 97 papers presented at the symposium. The primary topic was the evolution of the catalytic function. Speakers discussed the evolution of genetic apparatus, the primordial soup, the anatomy of RNA, RNA templates, protein assembly, protein structure, cofactors, ribosomes, exons, and introns. Individual papers were processed separately for the data base. (TEM)

  13. The Biological “Invariant of Motion” vs. “Struggle for Life”? On the Possible Quantum Mechanical Origin and Evolution of Semiotic Controls in Biology

    Directory of Open Access Journals (Sweden)

    András Balázs

    2013-10-01

    Full Text Available A novel, alternative and deeper view to the “selfish gene” paradigm is presented, describable as the “selfish code” frame. Introducing it, we put forth a quantum mechanical algorithm as a new description of the intracellular protein synthetizing machinery. The successive steps of the algorithm are, tentatively, semiotic constraints of the well-known quantum mechanical molecular “internal measurement” type. It is proposed that this molecular algorithm mediates a quantum mechanical time reversed dynamics with a primordial special version of this latter molecular measurement type (“mixed measurement” as its origin. It is furthermore suggested that this intracellular regressive algorithmical dynamics is a component of biological “motion”, the other, strongly coupled component being the macroscopic phenotypic motion. The biological “invariant of motion” of this hierarchically coupled overall generalized dynamics is suggested to be the evolutionally converged invariant genetic code vocabulary. It forms, possibly, the underlying internal “driving force” of evolution, as being “struggle for life”.

  14. The Coverage of Human Evolution in High School Biology Textbooks in the 20th Century and in Current State Science Standards

    Science.gov (United States)

    Skoog, Gerald

    2005-01-01

    Efforts to eliminate or neutralize the coverage of evolution in high school biology textbooks in the United States have persisted with varying degrees of intensity and success since the 1920s. In particular, the coverage of human evolution has been impacted by these efforts. Evidence of the success of these efforts can be chronicled by the…

  15. Evaluation of the biological role in the shore platform evolution. Development of specific methodology and first results.

    Science.gov (United States)

    Neves, Mario; Ramos-Pereira, Ana; Moura, Delminda; Trindade, Jorge; Gusmão, Francisca; Viegas, José; Santana, Paulo

    2010-05-01

    The formation and the evolution of shore platforms are dependent on several physical, chemical and biological processes. The weight of each of these processes is changeable not only from coast to coast but also within each shore platform. It depends on geographical, geomorphological, climatic and wave climate factors. In the lower intertidal zone of many rock coasts of the world, the biological cover of the surface is extremely high. This almost permanent wrap points out to a very strong biological influence on the downwearing rates and the erosive rhythm of these strips of the shore platforms. Yet, although there are several studies on the erosive ability of the individuals of each species that are found here, analyzed separately, research on the interactions among species with erosive and protective role in the present evolution of shore platforms are rare. The goal of the BISHOP Project - Bioprotection and bioerosion on shore platforms in the Algarve and Estremadura (Portugal South and West Coast) - is precisely to evaluate the bioprotective and bioerosive role of the communities of macro-organisms in the evolution of shore platforms cut in different type of rocks and in assorted environments. With that purpose, it was necessary to develop specific methodology. To quantify the downwearing of the shore platform, we used a TMEM (Traversing Micro-Erosion Meter) with an accuracy of 0,005mm, and capable of measuring 255 points in a 117 cm2 area. Four experimental places were chosen: two at calcarenite shore platforms of the Portuguese south coast, in a coastal zone exposed to the south and sheltered from the waves; and two in the Portuguese Estremadura, facing west on a well exposed coast to the North Atlantic energetic waves, on shore platforms cut in marly limestone. At each place, two pairs of monitoring areas were installed. For each pair, the same methodology was used. At the beginning, it was necessary to completely clean the biological cover of the two areas

  16. Evolution, Biology, and Society: A Conversation for the 21st-Century Sociology Classroom

    Science.gov (United States)

    Machalek, Richard; Martin, Michael W.

    2010-01-01

    Recently, a growing contingent of "evolutionary sociologists" has begun to integrate theoretical ideas and empirical findings derived from evolutionary biology, especially sociobiology, into a variety of sociological inquiries. Without capitulating to a naive version of either biological reductionism or genetic determinism, these researchers and…

  17. Analyzing Change in Students' Gene-to-Evolution Models in College-Level Introductory Biology

    Science.gov (United States)

    Dauer, Joseph T.; Momsen, Jennifer L.; Speth, Elena Bray; Makohon-Moore, Sasha C.; Long, Tammy M.

    2013-01-01

    Research in contemporary biology has become increasingly complex and organized around understanding biological processes in the context of systems. To better reflect the ways of thinking required for learning about systems, we developed and implemented a pedagogical approach using box-and-arrow models (similar to concept maps) as a foundational…

  18. Archeology, biology, anthropology: human evolution according to Gabriel de Mortillet and John Lubbock (France, England c. 1860-1870).

    Science.gov (United States)

    Richard, Nathalie

    2012-01-01

    This essay compares the first evolutionary syntheses on human prehistory formulated by John Lubbock (1865) in Britain and Gabriel de Mortillet (1869-1883) in France, which both brought the question of human evolution in multidisciplinary light by borrowing tools from archaeology and ethnology rather than from biology. This paper shows that these syntheses displayed similarities as well as differences, and intends to give a comparative assessment of some intellectual and social characteristics of British and French nineteenth-century prehistoric archaeology. Lubbock's and Mortillet's syntheses relied heavily on archaeological collections but these were of different content and status. They stressed progress but they were also organized in accordance to different visions of evolution. Both were articulated from political and religious standpoints, but these standpoints were different in their content and tone.

  19. Constructal law of design and evolution: Physics, biology, technology, and society

    Science.gov (United States)

    Bejan, Adrian; Lorente, Sylvie

    2013-04-01

    This is a review of the theoretical and applied progress made based on the Constructal law of design and evolution in nature, with emphasis on the last decade. The Constructal law is the law of physics that accounts for the natural tendency of all flow systems (animate and inanimate) to change into configurations that offer progressively greater flow access over time. The progress made with the Constructal law covers the broadest range of science, from heat and fluid flow and geophysics, to animal design, technology evolution, and social organization (economics, government). This review presents the state of this fast growing field, and draws attention to newly opened directions for original research. The Constructal law places the concepts of life, design, and evolution in physics.

  20. Toward the Language-Ready Brain: Biological Evolution and Primate Comparisons.

    Science.gov (United States)

    Arbib, Michael A

    2017-02-01

    The approach to language evolution suggested here focuses on three questions: How did the human brain evolve so that humans can develop, use, and acquire languages? How can the evolutionary quest be informed by studying brain, behavior, and social interaction in monkeys, apes, and humans? How can computational modeling advance these studies? I hypothesize that the brain is language ready in that the earliest humans had protolanguages but not languages (i.e., communication systems endowed with rich and open-ended lexicons and grammars supporting a compositional semantics), and that it took cultural evolution to yield societies (a cultural constructed niche) in which language-ready brains could become language-using brains. The mirror system hypothesis is a well-developed example of this approach, but I offer it here not as a closed theory but as an evolving framework for the development and analysis of conflicting subhypotheses in the hope of their eventual integration. I also stress that computational modeling helps us understand the evolving role of mirror neurons, not in and of themselves, but only in their interaction with systems "beyond the mirror." Because a theory of evolution needs a clear characterization of what it is that evolved, I also outline ideas for research in neurolinguistics to complement studies of the evolution of the language-ready brain. A clear challenge is to go beyond models of speech comprehension to include sign language and models of production, and to link language to visuomotor interaction with the physical and social world.

  1. Recent advances in alveolar biology: Evolution and function of alveolar proteins

    NARCIS (Netherlands)

    Orgeig, S.; Hiemstra, P.S.; Veldhuizen, E.J.A.; Casals, C.; Clark, H.W.; Hackzu, A.; Knudsen, L.; Possmayer, F.

    2010-01-01

    This review is focused on the evolution and function of alveolar proteins. The lung faces physical and environmental challenges, due to changing pressures/volumes and foreign pathogens, respectively. The pulmonary surfactant system is integral in protecting the lung from these challenges via two gro

  2. Alfred Russel Wallace (1823-1913): the forgotten co-founder of the Neo-Darwinian theory of biological evolution.

    Science.gov (United States)

    Kutschera, Ulrich; Hossfeld, Uwe

    2013-12-01

    The British naturalist Alfred Russel Wallace (1823-1913), who had to leave school aged 14 and never attended university, did extensive fieldwork, first in the Amazon River basin (1848-1852) and then in Southeast Asia (1854-1862). Based on this experience, and after reading the corresponding scientific literature, Wallace postulated that species were not created, but are modified descendants of pre-existing varieties (Sarawak Law paper, 1855). Evolution is brought about by a struggle for existence via natural selection, which results in the adaptation of those individuals in variable populations who survive and reproduce (Ternate essay, 1858). In his monograph Darwinism (1889), and in subsequent publications, Wallace extended the contents of Darwin's Origin of Species (1859) into the Neo-Darwinian theory of biological evolution, with reference to the work of August Weismann (1834-1914). Wallace also became the (co)-founder of biogeography, biodiversity research, astrobiology and evolutionary anthropology. Moreover, he envisioned what was later called the anthropocene (i.e., the age of human environmental destructiveness). However, since Wallace believed in atheistic spiritualism and mixed up scientific facts and supernatural speculations in some of his writings, he remains a controversial figure in the history of biology.

  3. The inception and evolution of a unique masters program in cancer biology, prevention and control.

    Science.gov (United States)

    Cousin, Carolyn; Blancato, Jan

    2010-09-01

    The University of the District of Columbia (UDC) and the Lombardi Comprehensive Cancer Center (LCCC), Georgetown University Medical Center established a Masters Degree Program in Cancer Biology, Prevention and Control at UDC that is jointly administered and taught by UDC and LCCC faculty. The goal of the Masters Degree Program is to educate students as master-level cancer professionals capable of conducting research and service in cancer biology, prevention, and control or to further advance the education of students to pursue doctoral studies. The Program's unique nature is reflected in its philosophy "the best cancer prevention and control researchers are those with a sound understanding of cancer biology". This program is a full-time, 2-year, 36-credit degree in which students take half of their coursework at UDC and half of their coursework at LCCC. During the second year, students are required to conduct research either at LCCC or UDC. Unlike most cancer biology programs, this unique Program emphasizes both cancer biology and cancer outreach training.

  4. [An increase in efficiency of adaptations and a weakening of organism protective reactions in the process of biological evolution].

    Science.gov (United States)

    Ivanov, K P

    2014-01-01

    The main direction of evolution of living organisms is development of the central nervous system and sense organ, an increase of energy exchange development of homoiothermia, development of the more and more complex forms of behavior, an increase in energy expenditure in connection with an increase of the organism activity, and development of adaptation to the habitat. Such fundamental processes were subjected and have been subjected to numerous studies and discussions. However, in different animals there exist different species peculiarities of evolution of physiological functions, from which finally formed are fundamental evolutionary processes. We studied some of these specific processes by dividing them into two categories. The first category is "Increase of efficiency of adaptation" in development of biological evolution. By this term we mean development of amazing by perfection specific physiological mechanisms of adaptive character. The second category is "Weakening of protective organism reactions". By this we understand disturbance of protective mechanisms of the organism immune system, discoordination of movement of leukocytes along microvessels, the absence of efficient collateral circulation in brain and in heart, etc.

  5. The development and validation of a scientific attitudes and attitudes toward evolution and creation instrument for Christian college biology students

    Science.gov (United States)

    Tenneson, Michael Gunnar

    2002-01-01

    This study reports on the development of a valid and reliable survey instrument to be used by college biology teachers at Christian colleges to evaluate the scientific attitudes and the attitudes about evolution and attitudes about creationism of their students. Survey questions were largely derived from student responses to open ended interview questions. Content validity was strong as indicated by agreement among content experts through the use of a content validity rating form. Construct validity was examined through the use of principal components analysis of 165 survey responses. Four factors were identified as a result of this analysis: "evolution support," "views of how scientists think/operate," "scientific attitudes," and "hypotheses and theories." These factors were found to be consistent with the three theoretical constructs of scientific attitudes, attitudes about evolution, and attitudes about creationism. Overall instrument reliability, Cronbach's reliability coefficient, alpha, was determined to be 0.64 (N = 165). Readability was found to be at the 7 th grade level. The instrument should be comprehensible by college students.

  6. Degrading organic micropollutants: The next challenge in the evolution of biological wastewater treatment processes

    Directory of Open Access Journals (Sweden)

    Naresh eSinghal

    2016-05-01

    Full Text Available Global water scarcity is driving the need for identifying new water source. Wastewater could be a potential water resource if appropriate treatment technologies could be developed. One of the barriers to obtaining high quality water from wastewater arises from the presence of organic micropollutants, which are biologically active at trace levels. Removal of these compounds from wastewater by current physico-chemical technologies is prohibitively expensive. While biological treatment processes are comparatively cheap, current systems are not capable of degrading the wide range of organic micropollutants present in wastewater. As current wastewater treatment processes were developed for treating conventional pollutants present at mg/L levels, degrading the ng/L levels of micropollutants will require a different approach to system design and operation. In this paper we discuss strategies that could be employed to develop biological wastewater treatment systems capable of degrading organic micropollutants.

  7. Biologic

    CERN Document Server

    Kauffman, L H

    2002-01-01

    In this paper we explore the boundary between biology and the study of formal systems (logic). In the end, we arrive at a summary formalism, a chapter in "boundary mathematics" where there are not only containers but also extainers ><, entities open to interaction and distinguishing the space that they are not. The boundary algebra of containers and extainers is to biologic what boolean algebra is to classical logic. We show how this formalism encompasses significant parts of the logic of DNA replication, the Dirac formalism for quantum mechanics, formalisms for protein folding and the basic structure of the Temperley Lieb algebra at the foundations of topological invariants of knots and links.

  8. Brain intersections of aesthetics and morals: perspectives from biology, neuroscience, and evolution.

    Science.gov (United States)

    Zaidel, D W; Nadal, M

    2011-01-01

    For centuries, only philosophers debated the relationship between aesthetics and morality. Recently, with advances in neuroscience, the debate has moved to include the brain and an evolved neural underpinning linking aesthetic reactions and moral judgment. Biological survival emphasizes mate selection strategies, and the ritual displays have been linked to human aesthetics in the arts, in faces, and in various daily decision making. In parallel, cultural human practices have evolved to emphasize altruism and morality. This article explores the biological background and discusses the neuroscientific evidence for shared brain pathways for aesthetics and morals.

  9. Enzymes useful for chiral compound synthesis: structural biology, directed evolution, and protein engineering for industrial use.

    Science.gov (United States)

    Kataoka, Michihiko; Miyakawa, Takuya; Shimizu, Sakayu; Tanokura, Masaru

    2016-07-01

    Biocatalysts (enzymes) have many advantages as catalysts for the production of useful compounds as compared to chemical catalysts. The stereoselectivity of the enzymes is one advantage, and thus the stereoselective production of chiral compounds using enzymes is a promising approach. Importantly, industrial application of the enzymes for chiral compound production requires the discovery of a novel useful enzyme or enzyme function; furthermore, improving the enzyme properties through protein engineering and directed evolution approaches is significant. In this review, the significance of several enzymes showing stereoselectivity (quinuclidinone reductase, aminoalcohol dehydrogenase, old yellow enzyme, and threonine aldolase) in chiral compound production is described, and the improvement of these enzymes using protein engineering and directed evolution approaches for further usability is discussed. Currently, enzymes are widely used as catalysts for the production of chiral compounds; however, for further use of enzymes in chiral compound production, improvement of enzymes should be more essential, as well as discovery of novel enzymes and enzyme functions.

  10. Internal Structure of Elementary Particle and Possible Deterministic Mechanism of Biological Evolution

    Directory of Open Access Journals (Sweden)

    Alexei V. Melkikh

    2004-03-01

    Full Text Available The possibility of a complicated internal structure of an elementary particle was analyzed. In this case a particle may represent a quantum computer with many degrees of freedom. It was shown that the probability of new species formation by means of random mutations is negligibly small. Deterministic model of evolution is considered. According to this model DNA nucleotides can change their state under the control of elementary particle internal degrees of freedom.

  11. Rapid evolution of dispersal ability makes biological invasions faster and more variable

    Science.gov (United States)

    Ochocki, Brad M.; Miller, Tom E. X.

    2017-01-01

    Genetic variation in dispersal ability may result in the spatial sorting of alleles during range expansion. Recent theory suggests that spatial sorting can favour the rapid evolution of life history traits at expanding fronts, and therefore modify the ecological dynamics of range expansion. Here we test this prediction by disrupting spatial sorting in replicated invasions of the bean beetle Callosobruchus maculatus across homogeneous experimental landscapes. We show that spatial sorting promotes rapid evolution of dispersal distance, which increases the speed and variability of replicated invasions: after 10 generations of range expansion, invasions subject to spatial sorting spread 8.9% farther and exhibit 41-fold more variable spread dynamics relative to invasions in which spatial sorting is suppressed. Correspondingly, descendants from spatially evolving invasions exhibit greater mean and variance in dispersal distance. Our results reveal an important role for rapid evolution during invasion, even in the absence of environmental filters, and argue for evolutionarily informed forecasts of invasive spread by exotic species or climate change migration by native species. PMID:28128215

  12. Genetic control of chromosome behaviour: Implications in evolution, crop improvement, and human biology

    Science.gov (United States)

    Chromosomes and chromosome pairing are pivotal to all biological sciences. The study of chromosomes helps unravel several aspects of an organism. Although the foundation of genetics occurred with the formulation of the laws of heredity in 1865, long before the discovery of chromosomes, their subsequ...

  13. The Origin and Evolution of Life in Pakistani High School Biology

    Science.gov (United States)

    Asghar, Anila; Wiles, Jason R.; Alters, Brian

    2010-01-01

    This study seeks to inform science education practitioners and researchers in the West about apparent attempts to reconcile science and religion in Pakistan's public school curriculum. We analysed the national high school science curriculum and biology textbooks (English) used in the Government schools in Pakistan, where Islamic faith is the…

  14. Biology, ecology and evolution of the family Gigasporaceae, arbuscular mycorrhizal fungi (Glomeromycota)

    NARCIS (Netherlands)

    Souza, Francisco Adriano de

    2005-01-01

    Research described in this thesis focused on biological, ecological and evolutionary aspects of Arbuscular Mycorrhizal Fungi (AMF), and in particular of the family Gigasporaceae (Gigaspora and Scutellospora, genera). This study had two major objectives. The first objective was to obtain better knowl

  15. Evolution, selection and cognition: from "learning" to parameter setting in biology and in the study of language.

    Science.gov (United States)

    Piattelli-Palmarini, M

    1989-02-01

    Most biologists and some cognitive scientists have independently reached the conclusion that there is no such thing as learning in the traditional "instructive" sense. This is, admittedly, a somewhat extreme thesis, but I defend it here in the light of data and theories jointly extracted from biology, especially from evolutionary theory and immunology, and from modern generative grammar. I also point out that the general demise of learning is uncontroversial in the biological sciences, while a similar consensus has not yet been reached in psychology and in linguistics at large. Since many arguments presently offered in defense of learning and in defense of "general intelligence" are often based on a distorted picture of human biological evolution, I devote some sections of this paper to a critique of "adaptationism," providing also a sketch of a better evolutionary theory (one based on "exaptation"). Moreover, since certain standard arguments presented today as "knock-down" in psychology, in linguistics and in artificial intelligence are a perfect replica of those once voiced by biologists in favor of instruction and against selection, I capitalize on these errors of the past to draw some lessons for the present and for the future.

  16. Systems biology of cancer: entropy, disorder, and selection-driven evolution to independence, invasion and "swarm intelligence".

    Science.gov (United States)

    Tarabichi, M; Antoniou, A; Saiselet, M; Pita, J M; Andry, G; Dumont, J E; Detours, V; Maenhaut, C

    2013-12-01

    Our knowledge of the biology of solid cancer has greatly progressed during the last few years, and many excellent reviews dealing with the various aspects of this biology have appeared. In the present review, we attempt to bring together these subjects in a general systems biology narrative. It starts from the roles of what we term entropy of signaling and noise in the initial oncogenic events, to the first major transition of tumorigenesis: the independence of the tumor cell and the switch in its physiology, i.e., from subservience to the organism to its own independent Darwinian evolution. The development after independence involves a constant dynamic reprogramming of the cells and the emergence of a sort of collective intelligence leading to invasion and metastasis and seldom to the ultimate acquisition of immortality through inter-individual infection. At each step, the probability of success is minimal to infinitesimal, but the number of cells possibly involved and the time scale account for the relatively high occurrence of tumorigenesis and metastasis in multicellular organisms.

  17. Sensory processing sensitivity: a review in the light of the evolution of biological responsivity.

    Science.gov (United States)

    Aron, Elaine N; Aron, Arthur; Jagiellowicz, Jadzia

    2012-08-01

    This article reviews the literature on sensory processing sensitivity (SPS) in light of growing evidence from evolutionary biology that many personality differences in nonhuman species involve being more or less responsive, reactive, flexible, or sensitive to the environment. After briefly defining SPS, it first discusses how biologists studying animal personality have conceptualized this general environmental sensitivity. Second, it reviews relevant previous human personality/temperament work, focusing on crossover interactions (where a trait generates positive or negative outcomes depending on the environment), and traits relevant to specific hypothesized aspects of SPS: inhibition of behavior, sensitivity to stimuli, depth of processing, and emotional/physiological reactivity. Third, it reviews support for the overall SPS model, focusing on development of the Highly Sensitive Person (HSP) Scale as a measure of SPS then on neuroimaging and genetic studies using the scale, all of which bears on the extent to which SPS in humans corresponds to biological responsivity.

  18. The cosmological model of eternal inflation and the transition from chance to biological evolution in the history of life

    Directory of Open Access Journals (Sweden)

    Koonin Eugene V

    2007-05-01

    Full Text Available Abstract Background Recent developments in cosmology radically change the conception of the universe as well as the very notions of "probable" and "possible". The model of eternal inflation implies that all macroscopic histories permitted by laws of physics are repeated an infinite number of times in the infinite multiverse. In contrast to the traditional cosmological models of a single, finite universe, this worldview provides for the origin of an infinite number of complex systems by chance, even as the probability of complexity emerging in any given region of the multiverse is extremely low. This change in perspective has profound implications for the history of any phenomenon, and life on earth cannot be an exception. Hypothesis Origin of life is a chicken and egg problem: for biological evolution that is governed, primarily, by natural selection, to take off, efficient systems for replication and translation are required, but even barebones cores of these systems appear to be products of extensive selection. The currently favored (partial solution is an RNA world without proteins in which replication is catalyzed by ribozymes and which serves as the cradle for the translation system. However, the RNA world faces its own hard problems as ribozyme-catalyzed RNA replication remains a hypothesis and the selective pressures behind the origin of translation remain mysterious. Eternal inflation offers a viable alternative that is untenable in a finite universe, i.e., that a coupled system of translation and replication emerged by chance, and became the breakthrough stage from which biological evolution, centered around Darwinian selection, took off. A corollary of this hypothesis is that an RNA world, as a diverse population of replicating RNA molecules, might have never existed. In this model, the stage for Darwinian selection is set by anthropic selection of complex systems that rarely but inevitably emerge by chance in the infinite universe

  19. Evolution through mutation and selection of biological and morphological features in the intertidal zone

    Science.gov (United States)

    Da Lio, C.; D'Alpaos, A.; Marani, M.

    2011-12-01

    The presence and continued existence of tidal morphologies, and in particular of salt marshes, is intimately connected with the presence/absence of halophytic vegetation. In fact, observations and models coupling morphodynamic and biological processes indicate that vegetation crucially affects the marsh equilibrium configurations in relation to the dissipation of wind waves and to the production of organic soil associated with the presence of plants. Often, different vegetation species live within very narrow elevation intervals, associated with similarly narrow ranges of environmental pressures (chiefly hypersalinity and hypoxia). Here we develop and use a 1D model of coupled biological-morphological mutation and selection to study how observed ecosystem properties emerge and how feedbacks between biological and morphological properties concur to select observed bio-morphic 'traits'. We see that the ability to transform their own environment, through increased inorganic deposition and organic soil production, allows vegetation species to more quickly develop adaptations to a changing forcing (e.g. sea level rise). Furthermore, we observe the emergence of zonation and succession and characterize the emerging biodiversity and ecosystem properties as a function of forcing characteristics (e.g. tidal range, rate of sea level rise, and inorganic sediment availability).

  20. Computing the origin and evolution of the ribosome from its structure — Uncovering processes of macromolecular accretion benefiting synthetic biology

    Directory of Open Access Journals (Sweden)

    Gustavo Caetano-Anollés

    2015-01-01

    Full Text Available Accretion occurs pervasively in nature at widely different timeframes. The process also manifests in the evolution of macromolecules. Here we review recent computational and structural biology studies of evolutionary accretion that make use of the ideographic (historical, retrodictive and nomothetic (universal, predictive scientific frameworks. Computational studies uncover explicit timelines of accretion of structural parts in molecular repertoires and molecules. Phylogenetic trees of protein structural domains and proteomes and their molecular functions were built from a genomic census of millions of encoded proteins and associated terminal Gene Ontology terms. Trees reveal a ‘metabolic-first’ origin of proteins, the late development of translation, and a patchwork distribution of proteins in biological networks mediated by molecular recruitment. Similarly, the natural history of ancient RNA molecules inferred from trees of molecular substructures built from a census of molecular features shows patchwork-like accretion patterns. Ideographic analyses of ribosomal history uncover the early appearance of structures supporting mRNA decoding and tRNA translocation, the coevolution of ribosomal proteins and RNA, and a first evolutionary transition that brings ribosomal subunits together into a processive protein biosynthetic complex. Nomothetic structural biology studies of tertiary interactions and ancient insertions in rRNA complement these findings, once concentric layering assumptions are removed. Patterns of coaxial helical stacking reveal a frustrated dynamics of outward and inward ribosomal growth possibly mediated by structural grafting. The early rise of the ribosomal ‘turnstile’ suggests an evolutionary transition in natural biological computation. Results make explicit the need to understand processes of molecular growth and information transfer of macromolecules.

  1. Lipid droplet biology and evolution illuminated by the characterization of a novel perilipin in teleost fish

    Science.gov (United States)

    Granneman, James G; Kimler, Vickie A; Zhang, Huamei; Ye, Xiangqun; Luo, Xixia; Postlethwait, John H; Thummel, Ryan

    2017-01-01

    Perilipin (PLIN) proteins constitute an ancient family important in lipid droplet (LD) formation and triglyceride metabolism. We identified an additional PLIN clade (plin6) that is unique to teleosts and can be traced to the two whole genome duplications that occurred early in vertebrate evolution. Plin6 is highly expressed in skin xanthophores, which mediate red/yellow pigmentation and trafficking, but not in tissues associated with lipid metabolism. Biochemical and immunochemical analyses demonstrate that zebrafish Plin6 protein targets the surface of pigment-containing carotenoid droplets (CD). Protein kinase A (PKA) activation, which mediates CD dispersion in xanthophores, phosphorylates Plin6 on conserved residues. Knockout of plin6 in zebrafish severely impairs the ability of CD to concentrate carotenoids and prevents tight clustering of CD within carotenoid bodies. Ultrastructural and functional analyses indicate that LD and CD are homologous structures, and that Plin6 was functionalized early in vertebrate evolution for concentrating and trafficking pigment. DOI: http://dx.doi.org/10.7554/eLife.21771.001 PMID:28244868

  2. United theory of biological evolution:Disaster-forced evolution through Supernova, radioactive ash fall-outs, genome instability, and mass extinctions

    Institute of Scientific and Technical Information of China (English)

    Toshikazu Ebisuzaki; Shigenori Maruyama

    2015-01-01

    We present the disaster-forced biological evolution model as a general framework that includes Darwinian “phylogenic gradualism”, Eldredge-Gould’s “punctuated equilibrium”, mass extinctions, and allopatric, parapatric, and sympatric speciation. It describes how reproductive isolation of organisms is established through global disasters due to supernova encounters and local disasters due to radioactive volcanic ash fall-outs by continental alkaline volcanism. Our new evolution model uniquely highlights three major factors of disaster-forced speciation: enhanced mutation rate by higher natural radiation level, smaller population size, and shrunken habitat size (i.e., isolation among the individual pop-ulations). We developed a mathematical model describing speciation of a half-isolated group from a parental group, taking into account the population size (Ne), immigration rate (m), and mutation rate (m). The model gives a quantitative estimate of the speciation, which is consistent with the observations of speciation speed. For example, the speciation takes at least 105 generations, if mutation rate is less than 10?3 per generation per individual. This result is consistent with the previous studies, in which m is assumed to be 10?3e10?5. On the other hand, the speciation is much faster (less than 105 generations) for the case that m is as large as 0.1 in parapatric conditions (mevolution during mass extinction events, such as observed during the Cambrian explosion of biodiversity. A similar rapid speciation (though in a much smaller

  3. United theory of biological evolution: Disaster-forced evolution through Supernova, radioactive ash fall-outs, genome instability, and mass extinctions

    Directory of Open Access Journals (Sweden)

    Toshikazu Ebisuzaki

    2015-01-01

    Full Text Available We present the disaster-forced biological evolution model as a general framework that includes Darwinian “phylogenic gradualism”, Eldredge-Gould's “punctuated equilibrium”, mass extinctions, and allopatric, parapatric, and sympatric speciation. It describes how reproductive isolation of organisms is established through global disasters due to supernova encounters and local disasters due to radioactive volcanic ash fall-outs by continental alkaline volcanism. Our new evolution model uniquely highlights three major factors of disaster-forced speciation: enhanced mutation rate by higher natural radiation level, smaller population size, and shrunken habitat size (i.e., isolation among the individual populations. We developed a mathematical model describing speciation of a half-isolated group from a parental group, taking into account the population size (Ne, immigration rate (m, and mutation rate (μ. The model gives a quantitative estimate of the speciation, which is consistent with the observations of speciation speed. For example, the speciation takes at least 105 generations, if mutation rate is less than 10−3 per generation per individual. This result is consistent with the previous studies, in which μ is assumed to be 10−3–10−5. On the other hand, the speciation is much faster (less than 105 generations for the case that μ is as large as 0.1 in parapatric conditions (m < μ. Even a sympatric (m ~ 1 speciation can occur within 103 generations, if mutation rate is very high (μ ~ 1 mutation per individual per generation, and if Ne < 20–30. Such a high mutation rate is possible during global disasters due to supernova encounters and local disasters due to radioactive ash fall-outs. They raise natural radiation level by a factor of 100–1000. Such rapid speciation events can also contribute to macro-evolution during mass extinction events, such as observed during the Cambrian explosion of biodiversity. A

  4. The cell biology of neurogenesis: toward an understanding of the development and evolution of the neocortex.

    Science.gov (United States)

    Taverna, Elena; Götz, Magdalena; Huttner, Wieland B

    2014-01-01

    Neural stem and progenitor cells have a central role in the development and evolution of the mammalian neocortex. In this review, we first provide a set of criteria to classify the various types of cortical stem and progenitor cells. We then discuss the issue of cell polarity, as well as specific subcellular features of these cells that are relevant for their modes of division and daughter cell fate. In addition, cortical stem and progenitor cell behavior is placed into a tissue context, with consideration of extracellular signals and cell-cell interactions. Finally, the differences across species regarding cortical stem and progenitor cells are dissected to gain insight into key developmental and evolutionary mechanisms underlying neocortex expansion.

  5. The evolution of ERMIONE in mitochondrial biogenesis and lipid homeostasis: An evolutionary view from comparative cell biology.

    Science.gov (United States)

    Wideman, Jeremy G; Muñoz-Gómez, Sergio A

    2016-08-01

    The ER-mitochondria organizing network (ERMIONE) in Saccharomyces cerevisiae is involved in maintaining mitochondrial morphology and lipid homeostasis. ERMES and MICOS are two scaffolding complexes of ERMIONE that contribute to these processes. ERMES is ancient but has been lost in several lineages including animals, plants, and SAR (stramenopiles, alveolates and rhizaria). On the other hand, MICOS is ancient and has remained present in all organisms bearing mitochondrial cristae. The ERMIONE precursor evolved in the α-proteobacterial ancestor of mitochondria which had the central subunit of MICOS, Mic60. The subsequent evolution of ERMIONE and its interactors in eukaryotes reflects the integrative co-evolution of mitochondria and their hosts and the adaptive paths that some lineages have followed in their specialization to certain environments. By approaching the ERMIONE from a perspective of comparative evolutionary cell biology, we hope to shed light on not only its evolutionary history, but also how ERMIONE components may function in organisms other than S. cerevisiae. This article is part of a Special Issue entitled: The cellular lipid landscape edited by Tim P. Levine and Anant K. Menon.

  6. Art and brain: the relationship of biology and evolution to art.

    Science.gov (United States)

    Zaidel, Dahlia W

    2013-01-01

    Visual art, as with all other arts, is spontaneously created only by humans and is ubiquitously present to various extents in all societies today. Exploring the deep roots of art from cognitive, neurological, genetic, evolutionary, archaeological, and biological perspectives is essential for the full understanding of why we have art, and what art is about. The cognitive basis of art is symbolic, abstract, and referential thinking. However, archaeological markers of symbolic activity by early humans are not associated with art production. There is an enormously large time gap between the activity and the appearance of sporadic art by early Homo sapiens, and another large time delay before appearance of enduring practice of art. The aesthetic aspect of art is not considered to be the initial impetus for creating it. Instead, archaeological markers suggest that the early beginnings of art are associated with development of stratified societies where external visual identifiers by way of body ornaments and decorations were used. The major contributing forces for the consistency in art-making are presumed to be the formation of socioculture, intragroup cooperation, increased group size, survival of skillful artisans, and favorable demographic conditions. The biological roots of art are hypothesized to parallel aspects of our ancestry, specifically animal courtship displays, where signals of health and genetic quality are exhibited for inspection by potential mates. Viewers assess displayed art for talent, skill, communicative, and aesthetic-related qualities. Interdisciplinary discussions of art reflect the current approach to full understanding of the nature of art.

  7. Origin, evolution, and biological role of miRNA cluster in DLK-DIO3 genomic region in placental mammals.

    Science.gov (United States)

    Glazov, Evgeny A; McWilliam, Sean; Barris, Wesley C; Dalrymple, Brian P

    2008-05-01

    MicroRNAs (miRNAs) are a rapidly growing family of small regulatory RNAs modulating gene expression in plants and animals. In animals, most of the miRNAs discovered in early studies were found to be evolutionarily conserved across the whole kingdom. More recent studies, however, have identified many miRNAs that are specific to a particular group of organisms or even a single species. These present a question about evolution of the individual miRNAs and their role in establishing and maintaining lineage-specific functions and characteristics. In this study, we describe a detailed analysis of the miRNA cluster (hereafter mir-379/mir-656 cluster) located within the imprinted DLK-DIO3 region on human chromosome 14. We show that orthologous miRNA clusters are present in all sequenced genomes of the placental (eutherian) mammals but not in the marsupial (metatherian), monotreme (prototherian), or any other vertebrate genomes. We provide evidence that the locus encompassing this cluster emerged in an early eutherian ancestor prior to the radiation of modern placental mammals by tandem duplication of the ancient precursor sequence. The original amplified cluster may have contained in excess of 250 miRNA precursor sequences, most of which now appear to be inactive. Examination of the eutherian genomes showed that the cluster has been maintained in evolution for approximately 100 Myr. Analysis of genes that contain predicted evolutionarily conserved targets for miRNAs from this cluster revealed significant overrepresentation of the Gene Ontology terms associated with biological processes such as neurogenesis, embryonic development, transcriptional regulation, and RNA metabolism. Consistent with these findings, a survey of the miRNA expression data within the cluster demonstrates a strong bias toward brain and placenta samples from adult organisms and some embryonic tissues. Our results suggest that emergence of the mir-379/mir-656 miRNA cluster was one of the factors that

  8. The Evolution of Human Basophil Biology from Neglect towards Understanding of Their Immune Functions

    Science.gov (United States)

    Steiner, Markus; Huber, Sara; Harrer, Andrea

    2016-01-01

    Being discovered long ago basophils have been neglected for more than a century. During the past decade evidence emerged that basophils share features of innate and adaptive immunity. Nowadays, basophils are best known for their striking effector role in the allergic reaction. They hence have been used for establishing new diagnostic tests and therapeutic approaches and for characterizing natural and recombinant allergens as well as hypoallergens, which display lower or diminished IgE-binding activity. However, it was a long way from discovery in 1879 until identification of their function in hypersensitivity reactions, including adverse drug reactions. Starting with a historical background, this review highlights the modern view on basophil biology. PMID:28078302

  9. Production and packaging of a biological arsenal: evolution of centipede venoms under morphological constraint.

    Science.gov (United States)

    Undheim, Eivind A B; Hamilton, Brett R; Kurniawan, Nyoman D; Bowlay, Greg; Cribb, Bronwen W; Merritt, David J; Fry, Bryan G; King, Glenn F; Venter, Deon J

    2015-03-31

    Venom represents one of the most extreme manifestations of a chemical arms race. Venoms are complex biochemical arsenals, often containing hundreds to thousands of unique protein toxins. Despite their utility for prey capture, venoms are energetically expensive commodities, and consequently it is hypothesized that venom complexity is inversely related to the capacity of a venomous animal to physically subdue prey. Centipedes, one of the oldest yet least-studied venomous lineages, appear to defy this rule. Although scutigeromorph centipedes produce less complex venom than those secreted by scolopendrid centipedes, they appear to rely heavily on venom for prey capture. We show that the venom glands are large and well developed in both scutigerid and scolopendrid species, but that scutigerid forcipules lack the adaptations that allow scolopendrids to inflict physical damage on prey and predators. Moreover, we reveal that scolopendrid venom glands have evolved to accommodate a much larger number of secretory cells and, by using imaging mass spectrometry, we demonstrate that toxin production is heterogeneous across these secretory units. We propose that the differences in venom complexity between centipede orders are largely a result of morphological restrictions of the venom gland, and consequently there is a strong correlation between the morphological and biochemical complexity of this unique venom system. The current data add to the growing body of evidence that toxins are not expressed in a spatially homogenous manner within venom glands, and they suggest that the link between ecology and toxin evolution is more complex than previously thought.

  10. Evolution of physical and biological characteristics of mesoscale eddy in north-central Red Sea

    Science.gov (United States)

    Zarokanellos, Nikolaos; Jones, Burton

    2015-04-01

    Eddies appear to be important to both the physical and biogeochemical dynamics of the Red Sea. Numerical simulations of physical dynamics and remote sensing studies of chlorophyll concentration and sea surface height in the Red Sea indicate their importance to the upper portions of the sea (Raitsos et al., 2013; Yao et al., 2014; Zhan et al., 2014). Despite their apparent importance, process studies of these eddies have been lacking. In March 2013 we began an extended observational study of the north-central Red Sea (NCRS) where anticyclonic eddies have been observed. The study began with a ship-based characterization of the eddy and was followed by a three-month observational time series using an autonomous glider equipped with a CTD, oxygen sensor, and optical sensors for chlorophyll, CDOM and optical backscatter. The ship-based study captured an initial snapshot of an anticyclonic eddy and it's associated biological and bio-optical distributions. Initially, chlorophyll distributions tended to mirror the density distribution, with deeper isopycnals and chlorophyll maximum depth in the anticyclonic eddy center. The anticyclone eddy in March had an along basin diameter of 150 km, penetrated vertically less than 150 m and elevated near surface chlorophyll concentrations appeared along its outer boundary. The shallowing of the pycnocline of the outer boundaries of the anticyclone eddy on March may elevate nutrients into the lower euphotic zone, contributing to phytoplankton productivity and biomass within the eddy. This eddy contains most of the kinetic energy of the region with the maximum velocities up to 30 - 35 cm/s. The eddy appeared to interact with the coastal reefs where exchange particulate and dissolved matter may occur. The autonomous glider provided the spring-to-summer progression of the system with increasing stratification, shallowing of the subsurface chlorophyll maximum, and fluctuations in the position and intensity of the eddy. Our glider effort

  11. Evolution of physical and biological characteristics of mesoscale eddy in north-central Red Sea

    KAUST Repository

    Zarokanellos, Nikolaos

    2015-04-01

    Eddies appear to be important to both the physical and biogeochemical dynamics of the Red Sea. Numerical simulations of physical dynamics and remote sensing studies of chlorophyll concentration and sea surface height in the Red Sea indicate their importance to the upper portions of the sea (Raitsos et al., 2013; Yao et al., 2014; Zhan et al., 2014). Despite their apparent importance, process studies of these eddies have been lacking. In March 2013 we began an extended observational study of the north-central Red Sea (NCRS) where anticyclonic eddies have been observed. The study began with a ship-based characterization of the eddy and was followed by a three-month observational time series using an autonomous glider equipped with a CTD, oxygen sensor, and optical sensors for chlorophyll, CDOM and optical backscatter. The ship-based study captured an initial snapshot of an anticyclonic eddy and it\\'s associated biological and bio-optical distributions. Initially, chlorophyll distributions tended to mirror the density distribution, with deeper isopycnals and chlorophyll maximum depth in the anticyclonic eddy center. The anticyclone eddy in March had an along basin diameter of 150 km, penetrated vertically less than 150 m and elevated near surface chlorophyll concentrations appeared along its outer boundary. The shallowing of the pycnocline of the outer boundaries of the anticyclone eddy on March may elevate nutrients into the lower euphotic zone, contributing to phytoplankton productivity and biomass within the eddy. This eddy contains most of the kinetic energy of the region with the maximum velocities up to 30 - 35 cm/s. The eddy appeared to interact with the coastal reefs where exchange particulate and dissolved matter may occur. The autonomous glider provided the spring-to-summer progression of the system with increasing stratification, shallowing of the subsurface chlorophyll maximum, and fluctuations in the position and intensity of the eddy. Our glider effort

  12. Sinapate esters in brassicaceous plants: biochemistry, molecular biology, evolution and metabolic engineering.

    Science.gov (United States)

    Milkowski, Carsten; Strack, Dieter

    2010-06-01

    Brassicaceous plants are characterized by a pronounced metabolic flux toward sinapate, produced by the shikimate/phenylpropanoid pathway, which is converted into a broad spectrum of O-ester conjugates. The abundant sinapate esters in Brassica napus and Arabidopsis thaliana reflect a well-known metabolic network, including UDP-glucose:sinapate glucosyltransferase (SGT), sinapoylglucose:choline sinapoyltransferase (SCT), sinapoylglucose:L-malate sinapoyltransferase (SMT) and sinapoylcholine (sinapine) esterase (SCE). 1-O-Sinapoylglucose, produced by SGT during seed development, is converted to sinapine by SCT and hydrolyzed by SCE in germinating seeds. The released sinapate feeds via sinapoylglucose into the biosynthesis of sinapoylmalate in the seedlings catalyzed by SMT. Sinapoylmalate is involved in protecting the leaves against the deleterious effects of UV-B radiation. Sinapine might function as storage vehicle for ready supply of choline for phosphatidylcholine biosynthesis in young seedlings. The antinutritive character of sinapine and related sinapate esters hamper the use of the valuable seed protein of the oilseed crop B. napus for animal feed and human nutrition. Due to limited variation in seed sinapine content within the assortment of B. napus cultivars, low sinapine lines cannot be generated by conventional breeding giving rise to genetic engineering of sinapate ester metabolism as a promising means. In this article we review the progress made throughout the last decade in identification of genes involved in sinapate ester metabolism and characterization of the encoded enzymes. Based on gene structures and enzyme recruitment, evolution of sinapate ester metabolism is discussed. Strategies of targeted metabolic engineering, designed to generate low-sinapate ester lines of B. napus, are evaluated.

  13. Life at extreme conditions: Neutron scattering studies of biological molecules suggest that evolution selected dynamics

    Indian Academy of Sciences (India)

    Joseph (Giuseppe) Zaccai

    2008-10-01

    The short review concentrates on recent work performed at the neutrons in biology laboratories of the Institut Laue Langevin and Institut de Biologie Structurale in Grenoble. Extremophile organisms have been discovered that require extreme conditions of temperature, pressure or solvent environment for survival. The existence of such organisms poses a significant challenge in understanding the physical chemistry of their proteins, in view of the great sensitivity of protein structure and stability to the aqueous environment and to external conditions in general. Results of neutron scattering measurements on the dynamics of proteins from extremophile organisms, in vitro as well as in vivo, indicated remarkably how adaptation to extreme conditions involves forces and fluctuation amplitudes that have been selected specifically, suggesting that evolutionary macromolecular selection proceeded via dynamics. The experiments were performed on a halophilic protein, and membrane adapted to high salt, a thermophilic enzyme adapted to high temperature and its mesophilic (adapted to 37°C) homologue; and in vivo for psychrophilic, mesophilic, thermophilic and hyperthermophilic bacteria, adapted respectively to temperatures of 4°C, 37°C, 75°C and 85°C. Further work demonstrated the existence of a water component of exceptionally low mobility in an extreme halophile from the Dead Sea, which is not present in mesophile bacterial cells.

  14. REDOX CHEMISTRY OF MOLYBDENUM IN NATURAL WATERS AND ITS INVOLVEMENT IN BIOLOGICAL EVOLUTION

    Directory of Open Access Journals (Sweden)

    Deli eWang

    2012-12-01

    Full Text Available The transition element molybdenum (Mo possesses diverse valances (+II to +VI, and is involved in forming cofactors in more than 60 enzymes in biology. Redox switching of the element in these enzymes catalyzes a series of metabolic reactions in both prokaryotes and eukaryotes, and the element therefore plays a fundamental role in the global carbon, nitrogen, and sulfur cycling. In the present oxygenated waters, oxidized Mo(VI predominates thermodynamically, whilst reduced Mo species are mainly confined within specific niches including cytoplasm. Only recently has the reduced Mo(V been separated from Mo(VI in sulfidic mats and even in some reducing waters. Given the presence of reduced Mo(V in contemporary anaerobic habitats, it seems that reduced Mo species were present in the ancient reducing ocean (probably under both ferrigenous and sulfidic conditions, prompting the involvement of Mo in enzymes including nitrogenase and nitrate reductase. During the global transition to oxic conditions, reduced Mo species were constrained to specific anaerobic habitats, and efficient uptake systems of oxidized Mo(VI became a selective advantage both for prokaryotic and eukaryotic cells. Some prokaryotes are still able to directly utilize reduced Mo if any exists in ambient environments. In total, this mini-review describes the redox chemistry and biogeochemistry of Mo over the Earth’s history.

  15. Teach Softly and Debunk with a Big Stick: A Response to "Evolution, Biology, and Society--A Conversation for the 21st-Century Sociology Classroom"

    Science.gov (United States)

    Hanson, Chad

    2010-01-01

    This article presents the author's response to "Evolution, Biology, and Society: A Conversation for the 21st-Century Sociology Classroom" by Richard Machalek and Michael Martin. Their work serves as a reminder that the discipline is diverse and dynamic. The author appreciates the effort to urge sociology teachers to include genetic concepts in…

  16. Climatic, tectonic, and biological factors affecting the oxidation state of the atmosphere and oceans: Implications for Phanerozoic O2 evolution

    Science.gov (United States)

    Ozaki, K.; Tajika, E.

    2015-12-01

    also shed light on the causal linkage between the critical biological evolution (such as an establishment of biological pump and advent of land plant) and the oxidation state of the atmosphere and oceans.

  17. Using Fossil Shark Teeth to Illustrate Evolution and Introduce Basic Geologic Concepts in a High School Biology Classroom

    Science.gov (United States)

    Agnew, J. G.; Nunn, J. A.

    2007-12-01

    Shell Foundation sponsors a program at Louisiana State University called Shell Undergraduate Recruitment and Geoscience Education (SURGE). The purpose of SURGE is to help local high school science teachers incorporate geology into their classrooms by providing resources and training. As part of this program, a workshop for high school biology teachers was held at Louisiana State University in Baton Rouge on June 3-5, 2007. We had the teachers do a series of activities on fossil shark teeth to illustrate evolution and introduce basic earth science concepts such as geologic time, superposition, and faunal succession and provided the teachers with lesson plans and materials. As an example, one of our exercises explores the evolution of the megatoothed shark lineage leading to Carcharocles megalodon, the largest predatory shark in history with teeth up to 17 cm long. Megatoothed shark teeth make excellent evolutionary subjects because they have a good fossil record and show continuous transitions in morphology from the Eocene to Pliocene. Our activity follows the learning cycle model. We take advantage of the curiosity of sharks shared by most people, and allow students to explore the variations among different shark teeth and explain the causes of those variations. The objectives of this exercise are to have the students: 1) sort fossil shark teeth into biologically reasonable species; 2) form hypotheses about evolutionary relationships among fossil shark teeth; and 3) describe and interpret evolutionary trends in the fossil Megatoothed lineage. To do the activity, students are divided into groups of 2-3 and given a shuffled set of 72 shark tooth cards with different images of megatoothed shark teeth. They are instructed to group the shark tooth cards into separate species of sharks. After sorting the cards, students are asked to consider the evolutionary relationships among their species and arrange their species chronologically according to the species first

  18. Animal lectins as self/non-self recognition molecules. Biochemical and genetic approaches to understanding their biological roles and evolution.

    Science.gov (United States)

    Vasta, G R; Ahmed, H; Fink, N E; Elola, M T; Marsh, A G; Snowden, A; Odom, E W

    1994-04-15

    In recent years, the significant contributions from molecular research studies on animal lectins have elucidated structural aspects and provided clues not only to their evolution but also to their multiple biological functions. The experimental evidence has suggested that distinct, and probably unrelated, groups of molecules are included under the term "lectin." Within the invertebrate taxa, major groups of lectins can be identified: One group would include lectins that show significant homology to membrane-integrated or soluble vertebrate C-type lectins. The second would include those beta-galactosyl-specific lectins homologous to the S-type vertebrate lectins. The third group would be constituted by lectins that show homology to vertebrate pentraxins that exhibit lectin-like properties, such as C-reactive protein and serum amyloid P. Finally, there are examples that do not exhibit similarities to any of the aforementioned categories. Moreover, the vast majority of invertebrate lectins described so far cannot yet be placed in one or another group because of the lack of information regarding their primary structure. (See Table 1.) Animal lectins do not express a recombinatorial diversity like that of antibodies, but a limited diversity in recognition capabilities would be accomplished by the occurrence of multiple lectins with distinct specificities, the presence of more than one binding site, specific for different carbohydrates in a single molecule, and by certain "flexibility" of the binding sites that would allow the recognition of a range of structurally related carbohydrates. In order to identify the lectins' "natural" ligands, we have investigated the interactions between those proteins and the putative endogenous or exogenous glycosylated substances or cells that may be relevant to their biological function. Results from these studies, together with information on the biochemical properties of invertebrate and vertebrate lectins, including their structural

  19. [Heterogeneity of the spatial distribution of the primordial organic substance as an initial stage of biological evolution].

    Science.gov (United States)

    Zhuravlev, Iu N; Tuzinkevich, A V; Frisman, E Ia

    2011-01-01

    An approach to describe the emergence of the primordial evolving system has been developed. The dynamics of polymerization/depolymerization of some spatially distributed prebiological structures has been analyzed, and two phases of the development of the system have been identified. In the first phase, the polymerization of organic monomers occurs by the influence of external factors, and in the second one depolymerization takes place. Both processes are accompanied by "diffuse mixing" of reaction products. The dynamic equations of the system are presented. The numerical examination of the space nonuniform solution of model equations has shown that, in conditions of low stability of uniform space distribution, these solutions resolve into a number of discrete peaks of non-zero density, which are isolated from each other by free space. Such nonuniform distributions are stable when being close to the bifurcation point; yet in other conditions, they can lose their stability, which entails a more pronounced nonuniformity of space dynamics. Thus, interaction of polymerization/depolymerization processes results in the chaotic self-organization and leads to the origination of complex and nomhomogeneous (putchy) spatial structures. These structures can reflect the emergency of the spatial nonuniformity in primordial associations, in physical space, in the distributive space of characters can correspond to the initial steps of individualization of the first discrete domains fixed in the biological evolution.

  20. The quantitative study of marked individuals in ecology, evolution and conservation biology: a foreword to the EURING 2003 Conference

    Directory of Open Access Journals (Sweden)

    Senar, J. C.

    2004-06-01

    Full Text Available Few fields in modern ecology have developed as fast as the analysis of marked individuals in the study of wild animal populations (Seber & Schwarz, 2002. This is the topic of EURING Conferences, which from 1986 have been the premier forum for advances in capture-recapture methodology. In this sense, EURING Conferences still maintain the flavour that originally inspired scientific meetings: to disseminate the very last findings, ideas and results on the field. Traditionally, EURING Conferences have been published in the form of Proceedings, which because of their relevant content, become a required reading to anyone interested in the capture-recapture methodology. EURING 2003 was held in Radolfzell (Germany, hosted by the Max Planck Research Centre for Ornithology, and the Proceedings appear as a special issue of Animal Biodiversity and Conservation. The full title of the 2003 meeting was “The quantitative study of marked individuals in ecology, evolution and conservation biology”, which stands for one of the main aims of the meeting: to establish the capture-recapture approach as one of the standard methodologies in studies within these fields. One of the shared views is that capture-recapture methodologies have reached a considerable maturity, but the need still exists to spread their use as a “standard” methodology. The nice review paper by Lebreton et al. (1993 in Trends in Ecology and Evolution is still applicable, in that general ecologists and evolutionary biologists still resist their general use. The same applies to conservation biology, where the analysis of marked individuals may also be a key tool in its development. We hope, with the spread of 2003 Proceedings, to help to fill this gap. The Proceedings follow the same general structure as the Conference. We organised the EURING meeting in 10 technical sessions, covering what we considered as fastest growing areas in the field. We appointed for each session, two chairs, which

  1. 进化论与进化生物学的发展%Theory of Evolution and Development of Evolutionary Biology

    Institute of Scientific and Technical Information of China (English)

    钟扬

    2009-01-01

    @@ 自达尔文1859年发表(The Origin ofSpecies)一书以来,"进化"(evolution)已逐渐成为生物学文献中出现频率最高的词汇之一,进化生物学(evo-lutionary biology)则成为当今生命科学中一个重要的前沿领域.

  2. Etiology of lumbar lordosis and its pathophysiology: a review of the evolution of lumbar lordosis, and the mechanics and biology of lumbar degeneration.

    Science.gov (United States)

    Sparrey, Carolyn J; Bailey, Jeannie F; Safaee, Michael; Clark, Aaron J; Lafage, Virginie; Schwab, Frank; Smith, Justin S; Ames, Christopher P

    2014-05-01

    The goal of this review is to discuss the mechanisms of postural degeneration, particularly the loss of lumbar lordosis commonly observed in the elderly in the context of evolution, mechanical, and biological studies of the human spine and to synthesize recent research findings to clinical management of postural malalignment. Lumbar lordosis is unique to the human spine and is necessary to facilitate our upright posture. However, decreased lumbar lordosis and increased thoracic kyphosis are hallmarks of an aging human spinal column. The unique upright posture and lordotic lumbar curvature of the human spine suggest that an understanding of the evolution of the human spinal column, and the unique anatomical features that support lumbar lordosis may provide insight into spine health and degeneration. Considering evolution of the skeleton in isolation from other scientific studies provides a limited picture for clinicians. The evolution and development of human lumbar lordosis highlight the interdependence of pelvic structure and lumbar lordosis. Studies of fossils of human lineage demonstrate a convergence on the degree of lumbar lordosis and the number of lumbar vertebrae in modern Homo sapiens. Evolution and spine mechanics research show that lumbar lordosis is dictated by pelvic incidence, spinal musculature, vertebral wedging, and disc health. The evolution, mechanics, and biology research all point to the importance of spinal posture and flexibility in supporting optimal health. However, surgical management of postural deformity has focused on restoring posture at the expense of flexibility. It is possible that the need for complex and costly spinal fixation can be eliminated by developing tools for early identification of patients at risk for postural deformities through patient history (genetics, mechanics, and environmental exposure) and tracking postural changes over time.

  3. Investigating Greek Biology Teachers' Attitudes towards Evolution Teaching with Respect to Their Pedagogical Content Knowledge: Suggestions for Their Professional Development

    Science.gov (United States)

    Stasinakis, Panagiotis K.; Athanasiou, Kyriacos

    2016-01-01

    Evolution Teaching (ET) among in-service teachers in Greece was examined in an attempt to evaluate their Pedagogical Content Knowledge. Evolution teaching is a problematic issue. For this purpose, we constructed a questionnaire that was distributed to the target population and to which 181 teachers responded. We used quantitative method to…

  4. Evolution in the Caribbean Classroom: A Critical Analysis of the Role of Biology Teachers and Science Standards in Shaping Evolution Instruction in Belize

    Science.gov (United States)

    Nunez, Elvis Enrique; Pringle, Rose M.; Showalter, Kevin Tyler

    2012-01-01

    A survey of the literature on evolution instruction provides evidence that teachers' personal views and understandings can shape instructional approaches and content delivered in science classrooms regardless of established science standards. This study is the first to quantify evolutionary worldviews of in-service teachers in the Caribbean,…

  5. Biological computation

    CERN Document Server

    Lamm, Ehud

    2011-01-01

    Introduction and Biological BackgroundBiological ComputationThe Influence of Biology on Mathematics-Historical ExamplesBiological IntroductionModels and Simulations Cellular Automata Biological BackgroundThe Game of Life General Definition of Cellular Automata One-Dimensional AutomataExamples of Cellular AutomataComparison with a Continuous Mathematical Model Computational UniversalitySelf-Replication Pseudo Code Evolutionary ComputationEvolutionary Biology and Evolutionary ComputationGenetic AlgorithmsExample ApplicationsAnalysis of the Behavior of Genetic AlgorithmsLamarckian Evolution Genet

  6. Teaching Evolution at A-Level: Is "Intelligent Design" a Scientific Theory That Merits Inclusion in the Biology Syllabus?

    Science.gov (United States)

    Freeland, Peter

    2013-01-01

    Charles Darwin supposed that evolution involved a process of gradual change, generated randomly, with the selection and retention over many generations of survival-promoting features. Some theists have never accepted this idea. "Intelligent design" is a relatively recent theory, supposedly based on scientific evidence, which attempts to…

  7. Ancestral state reconstructions require biological evidence to test evolutionary hypotheses: A case study examining the evolution of reproductive mode in squamate reptiles.

    Science.gov (United States)

    Griffith, Oliver W; Blackburn, Daniel G; Brandley, Matthew C; Van Dyke, James U; Whittington, Camilla M; Thompson, Michael B

    2015-09-01

    To understand evolutionary transformations it is necessary to identify the character states of extinct ancestors. Ancestral character state reconstruction is inherently difficult because it requires an accurate phylogeny, character state data, and a statistical model of transition rates and is fundamentally constrained by missing data such as extinct taxa. We argue that model based ancestral character state reconstruction should be used to generate hypotheses but should not be considered an analytical endpoint. Using the evolution of viviparity and reversals to oviparity in squamates as a case study, we show how anatomical, physiological, and ecological data can be used to evaluate hypotheses about evolutionary transitions. The evolution of squamate viviparity requires changes to the timing of reproductive events and the successive loss of features responsible for building an eggshell. A reversal to oviparity requires that those lost traits re-evolve. We argue that the re-evolution of oviparity is inherently more difficult than the reverse. We outline how the inviability of intermediate phenotypes might present physiological barriers to reversals from viviparity to oviparity. Finally, we show that ecological data supports an oviparous ancestral state for squamates and multiple transitions to viviparity. In summary, we conclude that the first squamates were oviparous, that frequent transitions to viviparity have occurred, and that reversals to oviparity in viviparous lineages either have not occurred or are exceedingly rare. As this evidence supports conclusions that differ from previous ancestral state reconstructions, our paper highlights the importance of incorporating biological evidence to evaluate model-generated hypotheses.

  8. A paradigm for viewing biologic systems as scale-free networks based on energy efficiency: implications for present therapies and the future of evolution.

    Science.gov (United States)

    Yun, Anthony J; Lee, Patrick Y; Doux, John D

    2006-01-01

    A network constitutes an abstract description of the relationships among entities, respectively termed links and nodes. If a power law describes the probability distribution of the number of links per node, the network is said to be scale-free. Scale-free networks feature link clustering around certain hubs based on preferential attachments that emerge due either to merit or legacy. Biologic systems ranging from sub-atomic to ecosystems represent scale-free networks in which energy efficiency forms the basis of preferential attachments. This paradigm engenders a novel scale-free network theory of evolution based on energy efficiency. As environmental flux induces fitness dislocations and compels a new meritocracy, new merit-based hubs emerge, previously merit-based hubs become legacy hubs, and network recalibration occurs to achieve system optimization. To date, Darwinian evolution, characterized by innovation sampling, variation, and selection through filtered termination, has enabled biologic progress through optimization of energy efficiency. However, as humans remodel their environment, increasing the level of unanticipated fitness dislocations and inducing evolutionary stress, the tendency of networks to exhibit inertia and retain legacy hubs engender maladaptations. Many modern diseases may fundamentally derive from these evolutionary displacements. Death itself may constitute a programmed adaptation, terminating individuals who represent legacy hubs and recalibrating the network. As memes replace genes as the basis of innovation, death itself has become a legacy hub. Post-Darwinian evolution may favor indefinite persistence to optimize energy efficiency. We describe strategies to reprogram or decommission legacy hubs that participate in human disease and death.

  9. Geochemistry of U and Th and its Influence on the Origin and Evolution of the Crust of Earth and the Biological Evolution

    CERN Document Server

    Bao, Xuezhao

    1998-01-01

    We have investigated the migration behaviors of uranium (U) and thorium (Th) in the Earth and other terrestrial planets. Theoretical models of U and Th migration have been proposed. These models suggest that the unique features of the Earth are closely connected with its unique U and Th migration models and distribution patterns. In the Earth, U and Th can combine with oxidative volatile components and water, migrate up to the asthenosphere position to form an enrichment zone (EZ) of U and Th first, and then migrate up further to the crusts through magmatism and metamorphism. We emphasize that the formation of an EZ of U, Th and other heat-producing elements is a prerequisite for the formation of a plate tectonic system. The heat-producing elements, currently mainly U and Th, in the EZ are also the energy sources that drive the formation and evolution of the crust of Earth and create special granitic continental crusts. In other terrestrial planets, including Mercury, Venus, and Mars, an EZ can not be formed ...

  10. Derivation of the extrinsic values of biological diversity from its intrinsic value and of both from the first principles of evolution.

    Science.gov (United States)

    White, Peter S

    2013-12-01

    Conservation ethics have been based on 2 philosophical value systems: extrinsic value (defined broadly to include all values that derive from something external to the thing valued) and intrinsic value. Valuing biological diversity on the basis of an extrinsic value system is problematic because measurement is often difficult; extrinsic value changes as spatial or temporal scales change; extrinsic value differs on the basis of external factors; some species have trivial or negative extrinsic values; and extrinsic value varies across human cultures and societies and with such factors as socioeconomic conditions, individual experiences, and educational backgrounds. Valuing biological diversity on the basis of an intrinsic value system also poses challenges because intrinsic value can be seen as a disguised form of human extrinsic value; intrinsic value is initially ambiguous as to which objects or characteristics of biological diversity are to being valued; all aspects of biological diversity (e.g., species and ecosystems) are transitory; species and ecosystems are not static concrete entities; and intrinsic value of one species is often in conflict with the intrinsic value of other species. Extrinsic and intrinsic value systems share a common origin, such that extrinsic values are always derived from intrinsic value and life mutely expresses both intrinsic and extrinsic values-these are derived from and are products of biological evolution. Probing the values that underlie conservation helps the community clearly articulate its aims. Derivación de los Valores Extrínsecos de la Biodiversidad a Partir de sus Valores Intrínsecos y de Ambos a Partir de los Primeros Principios de la Evolución.

  11. Has Human Evolution Stopped?

    OpenAIRE

    TEMPLETON, Alan R

    2010-01-01

    It has been argued that human evolution has stopped because humans now adapt to their environment via cultural evolution and not biological evolution. However, all organisms adapt to their environment, and humans are no exception. Culture defines much of the human environment, so cultural evolution has actually led to adaptive evolution in humans. Examples are given to illustrate the rapid pace of adaptive evolution in response to cultural innovations. These adaptive responses have important ...

  12. Evolution of natural history information in the 21st century – developing an integrated framework for biological and geographical data

    Science.gov (United States)

    Reusser, Deborah A.; Lee, Henry

    2011-01-01

    Threats to marine and estuarine species operate over many spatial scales, from nutrient enrichment at the watershed/estuarine scale to invasive species and climate change at regional and global scales. To help address research questions across these scales, we provide here a standardized framework for a biogeographical information system containing queriable biological data that allows extraction of information on multiple species, across a variety of spatial scales based on species distributions, natural history attributes and habitat requirements. As scientists shift from research on localized impacts on individual species to regional and global scale threats, macroecological approaches of studying multiple species over broad geographical areas are becoming increasingly important. The standardized framework described here for capturing and integrating biological and geographical data is a critical first step towards addressing these macroecological questions and we urge organizations capturing biogeoinformatics data to consider adopting this framework.

  13. Toward a mathematical theory of living systems focusing on developmental biology and evolution: A review and perspectives

    Science.gov (United States)

    Bellomo, N.; Carbonaro, B.

    2011-03-01

    This review paper is devoted to present a personal perspective, based on a critical analysis of the existing literature, about the conceptual difficulties that mathematics meets when attempting to describe the complexity of living matter focusing on the challenging goal of developing a mathematical theory for living systems. The authors propose a personal path, starting from the identification of a number of common features of living systems that can be viewed as sources of complexity, firstly in general, and subsequently focusing specifically on evolution problems. Further, three key questions are posed addressing to a mathematical theory. Finally, the tools of the kinetic theory of active particles are critically analyzed to understand how far this approach still is from the achievement of the afore said ambitious objective.

  14. Fundamental Issues Related to the Origin of Melatonin and Melatonin Isomers during Evolution: Relation to Their Biological Functions

    Directory of Open Access Journals (Sweden)

    Dun-Xian Tan

    2014-09-01

    Full Text Available Melatonin and melatonin isomers exist and/or coexist in living organisms including yeasts, bacteria and plants. The levels of melatonin isomers are significantly higher than that of melatonin in some plants and in several fermented products such as in wine and bread. Currently, there are no reports documenting the presence of melatonin isomers in vertebrates. From an evolutionary point of view, it is unlikely that melatonin isomers do not exist in vertebrates. On the other hand, large quantities of the microbial flora exist in the gut of the vertebrates. These microorganisms frequently exchange materials with the host. Melatonin isomers, which are produced by these organisms inevitably enter the host’s system. The origins of melatonin and its isomers can be traced back to photosynthetic bacteria and other primitive unicellular organisms. Since some of these bacteria are believed to be the precursors of mitochondria and chloroplasts these cellular organelles may be the primary sites of melatonin production in animals or in plants, respectively. Phylogenic analysis based on its rate-limiting synthetic enzyme, serotonin N-acetyltransferase (SNAT, indicates its multiple origins during evolution. Therefore, it is likely that melatonin and its isomer are also present in the domain of archaea, which perhaps require these molecules to protect them against hostile environments including extremely high or low temperature. Evidence indicates that the initial and primary function of melatonin and its isomers was to serve as the first-line of defence against oxidative stress and all other functions were acquired during evolution either by the process of adoption or by the extension of its antioxidative capacity.

  15. [Social institutions and tempering of affects as "contraints" of social change. Norbert Elias' theory on the civilization theory in light of the biologic system theory of evolution].

    Science.gov (United States)

    Weinich, Detlef

    2005-01-01

    This study is to be regarded as a contribution to interdisciplinary research and represents an attempt to clarify the question of whether and to what extent concepts that have been developed in the field of theoretical biology and which have a high degree of importance here can also be applied to sociological phenomena. In particular it is intended to examine the question of whether the civilizing process can be adequately treated using the evolutionary concept of "Constraints". This term, which has only recently been introduced into the discussion by PERE ALBERCH as an evolutionary factor, comprises all of the internal factors which influence the further course of the evolution of a system by ruling out certain possibilities, thus showing a limiting effect. Although "Constraints" go beyond the scope of Darwinian teachings about selection by the environment, they are increasingly accepted today as evolution factors by well-known exponents of Darwinian theory (cf. MAYNARD-SMITH 1985). The increase in popularity of "constraints" is also an expression of the rediscovery of a phenomenon which was originally expressed by RUPERT RIEDL and was introduced by him into German literature in the seventies. In the clarification of this question, special reference is made to the "theory of the civilizing process" by NORBERT ELIAS, since here a highly respected scholar has presented an important sociological theory. Moreover, there is such good scientific access to ELIAS because this author exemplifies his theses in historical terms and thus to a certain extent makes his explanations verifiable in scientific terms. In the treatment of this topic, the central terms and theses of ELIAS will be presented from the considerable scope of his work, and then illustrated with the help of several selected historical case studies. Furthermore, reference will be made at the relevant points to parallels and analogies which the works of ELIAS have to other, predominantly system

  16. Structural insights into the evolution of a non-biological protein: importance of surface residues in protein fold optimization.

    Directory of Open Access Journals (Sweden)

    Matthew D Smith

    Full Text Available Phylogenetic profiling of amino acid substitution patterns in proteins has led many to conclude that most structural information is carried by interior core residues that are solvent inaccessible. This conclusion is based on the observation that buried residues generally tolerate only conserved sequence changes, while surface residues allow more diverse chemical substitutions. This notion is now changing as it has become apparent that both core and surface residues play important roles in protein folding and stability. Unfortunately, the ability to identify specific mutations that will lead to enhanced stability remains a challenging problem. Here we discuss two mutations that emerged from an in vitro selection experiment designed to improve the folding stability of a non-biological ATP binding protein. These mutations alter two solvent accessible residues, and dramatically enhance the expression, solubility, thermal stability, and ligand binding affinity of the protein. The significance of both mutations was investigated individually and together, and the X-ray crystal structures of the parent sequence and double mutant protein were solved to a resolution limit of 2.8 and 1.65 A, respectively. Comparative structural analysis of the evolved protein to proteins found in nature reveals that our non-biological protein evolved certain structural features shared by many thermophilic proteins. This experimental result suggests that protein fold optimization by in vitro selection offers a viable approach to generating stable variants of many naturally occurring proteins whose structures and functions are otherwise difficult to study.

  17. Nitrogen Substituted Polycyclic Aromatic Hydrocarbon As Capable Interstellar Infrared Spectrum Source Considering Astronomical Chemical Evolution Step To Biological Organic Purine And Adenine

    CERN Document Server

    Ota, Norio

    2016-01-01

    In order to find out capable chemical evolution step from astronomically created organic in interstellar space to biological organic on the earth, infrared spectrum of nitrogen substituted carbon pentagon-hexagon coupled polycyclic aromatic hydrocarbon was analyzed by the density functional theory. Ionization was modeled from neutral to tri-cation. Among one nitrogen and two nitrogen substituted NPAH, we could find good examples showing similar IR behavior with astronomically well observed one as like C8H6N1, C7H5N2, and C7H5N2. We can imagine that such ionized NPAH may be created in interstellar space by attacks of high energy nitrogen and photon. Whereas, in case of three and four nitrogen substituted cases as like C6H4N3 and C5H3N4, there were no candidate showing similar behavior with observed one. Also, IR of typical biological organic with four and five nitrogen substituted one as like purine and adenine resulted no good similarity with observed one. By such theoretical comparison, one capable story of ...

  18. Testing biological hypotheses with embodied robots: adaptations, accidents, and by-products in the evolution of vertebrates

    Directory of Open Access Journals (Sweden)

    Sonia F Roberts

    2014-11-01

    Full Text Available Evolutionary robotics allows biologists to test hypotheses about extinct animals. We modeled some of the first vertebrates, jawless fishes, in order to study the evolution of the trait after which vertebrates are named: vertebrae. We tested the hypothesis that vertebrae are an adaptation for enhanced feeding and fleeing performance. We created a population of autonomous embodied robots, Preyro, in which the number of vertebrae, N, were free to evolve. In addition, two other traits, the span of the caudal fin, b, and the predator detection threshold, ζ, a proxy for the lateral line sensory system, were also allowed to evolve. These three traits were chosen because they evolved early in vertebrates, are all potentially important in feeding and fleeing, and vary in form among species. Preyro took on individual identities in a given generation as defined by the population’s six diploid genotypes, Gi. Each Gi was a 3-tuple, with each element an integer specifying N, b, and, ζ. The small size of the population allowed for genetic drift to operate in concert with random mutation and mating; the presence of these mechanisms of chance provided an opportunity for N to evolve by accident. The presence of three evolvable traits provided an opportunity for direct selection on b and/or ζ to evolve N as a by-product linked trait correlation. In selection trials, different Gi embodied in Preyro attempted to feed at a light source and then flee to avoid a predator robot in pursuit. The fitness of each Gi was calculated from five different types of performance: speed, acceleration, distance to the light, distance to the predator, and the number of predator escapes initiated. In each generation, we measured the selection differential, the selection gradient, the strength of chance, and the indirect correlation selection gradient. These metrics allowed us to understand the relative contributions of the three mechanisms: direct selection, chance, and indirect

  19. Testing the museum versus cradle tropical biological diversity hypothesis: phylogeny, diversification, and ancestral biogeographic range evolution of the ants.

    Science.gov (United States)

    Moreau, Corrie S; Bell, Charles D

    2013-08-01

    Ants are one of the most ecologically and numerically dominant group of terrestrial organisms with most species diversity currently found in tropical climates. Several explanations for the disparity of biological diversity in the tropics compared to temperate regions have been proposed including that the tropics may act as a "museum" where older lineages persist through evolutionary time or as a "cradle" where new species continue to be generated. We infer the molecular phylogenetic relationships of 295 ant specimens including members of all 21 extant subfamilies to explore the evolutionary diversification and biogeography of the ants. By constraining the topology and age of the root node while using 45 fossils as minimum constraints, we converge on an age of 139-158 Mya for the modern ants. Further diversification analyses identified 10 periods with a significant change in the tempo of diversification of the ants, although these shifts did not appear to correspond to ancestral biogeographic range shifts. Likelihood-based historical biogeographic reconstructions suggest that the Neotropics were important in early ant diversification (e.g., Cretaceous). This finding coupled with the extremely high-current species diversity suggests that the Neotropics have acted as both a museum and cradle for ant diversity.

  20. Applying x-ray tomography in the field of vertebrate biology: form, function, and evolution of the skull of caecilians (Lissamphibia: Gymnophiona)

    Science.gov (United States)

    Kleinteich, Thomas; Beckmann, Felix; Herzen, Julia; Summers, Adam P.; Haas, Alexander

    2008-08-01

    Evolutionary research in biology relies on the comparison of different individuals of different species in order to explore the history of today's biodiversity. Synchrotron radiation based high resolution X-ray tomography (SRμCT) rapidly generates detailed three dimensional datasets. At the beamlines W2 and BW2 of the storage ring DORIS at DESY, Hamburg, Germany, we used SRμCT to study the cranial anatomy of different species and different developmental stages of caecilians (Lissamphibia: Gymnophiona). Here we describe a work-flow for analysis of the SRμCT data that covers segmentation of tissues in Amira® (Mercury Computer Systems), photorealistic rendering and animation in MayaTM, rapid prototyping, and morphometrics. The integration of different analyses of SRμCT data in our study resulted in a comprehensive understanding of form, function, and evolution of caecilian skulls. SRμCT imaging has the potential to become a standard technique for life sciences applications in the near future.

  1. Bioenergetics in human evolution and disease: implications for the origins of biological complexity and the missing genetic variation of common diseases.

    Science.gov (United States)

    Wallace, Douglas C

    2013-07-19

    Two major inconsistencies exist in the current neo-Darwinian evolutionary theory that random chromosomal mutations acted on by natural selection generate new species. First, natural selection does not require the evolution of ever increasing complexity, yet this is the hallmark of biology. Second, human chromosomal DNA sequence variation is predominantly either neutral or deleterious and is insufficient to provide the variation required for speciation or for predilection to common diseases. Complexity is explained by the continuous flow of energy through the biosphere that drives the accumulation of nucleic acids and information. Information then encodes complex forms. In animals, energy flow is primarily mediated by mitochondria whose maternally inherited mitochondrial DNA (mtDNA) codes for key genes for energy metabolism. In mammals, the mtDNA has a very high mutation rate, but the deleterious mutations are removed by an ovarian selection system. Hence, new mutations that subtly alter energy metabolism are continuously introduced into the species, permitting adaptation to regional differences in energy environments. Therefore, the most phenotypically significant gene variants arise in the mtDNA, are regional, and permit animals to occupy peripheral energy environments where rarer nuclear DNA (nDNA) variants can accumulate, leading to speciation. The neutralist-selectionist debate is then a consequence of mammals having two different evolutionary strategies: a fast mtDNA strategy for intra-specific radiation and a slow nDNA strategy for speciation. Furthermore, the missing genetic variation for common human diseases is primarily mtDNA variation plus regional nDNA variants, both of which have been missed by large, inter-population association studies.

  2. Investigating Human Evolution Using Digital Imaging & Craniometry

    Science.gov (United States)

    Robertson, John C.

    2007-01-01

    Human evolution is an important and intriguing area of biology. The significance of evolution as a component of biology curricula, at all levels, can not be overstated; the need to make the most of opportunities to effectively educate students in evolution as a central and unifying realm of biology is paramount. Developing engaging laboratory or…

  3. Evidence for biological mediation of K and P weathering inferred from a new process-based soil evolution model and soil chronosequences from Hawaii

    Science.gov (United States)

    Johnson, M.; Gloor, E.

    2012-12-01

    The productivity of many tropical forests is limited by the availability of nutrients such as phosphorus (P). Nutrient limitation thus has consequences for the global climate because it alters the response of vegetation productivity to changing CO2 concentrations. The amount of mineral derived nutrients available to vegetation depends upon a number of factors such as the age of the soil, the weatherability of rock minerals, the mechanism of nutrient uptake by the vegetation and the leaching intensity of the soils. An understanding of the interactions between pedogenetic processes and nutrient cycling can therefore enhance our understanding of ecosystem dynamics. Studies examining the interactions between soil processes and nutrient availability are limited, mainly because of the long timescales over which many of these processes operate and of the difficulty in isolating individual soil processes. Data from soil climate-sequences and chronosequences can potentially shed light on these interactions when combined with a model which includes soil forming processes over pedogenic timescales. We have developed a process-based soil evolution model which can be evaluated with measurements of soil properties in order to understand such biogeochemical cycles. The mechanistic, soil evolution model presented includes the major processes of soil formation including i) mineral weathering, ii) percolation of rainfall, iii) leaching of solutes, iv) surface erosion, v) bioturbation and vi) vegetation-soil interactions. The specific properties the model simulates over timescales of tens to hundreds of thousand years are, soil depth, vertical profiles of elemental composition, soil solution pH and organic carbon distribution. Modelled soil properties are compared with measured soil properties from basaltic soil chronosequences in Hawaii. The model generally agrees well with the soil chronosequences. Here we focus on one particularly interesting result regarding the role of the

  4. Space biology research development

    Science.gov (United States)

    Bonting, Sjoerd L.

    1993-01-01

    The purpose of the Search for Extraterrestrial Intelligence (SETI) Institute is to conduct and promote research related activities regarding the search for extraterrestrial life, particularly intelligent life. Such research encompasses the broad discipline of 'Life in the Universe', including all scientific and technological aspects of astronomy and the planetary sciences, chemical evolution, the origin of life, biological evolution, and cultural evolution. The primary purpose was to provide funding for the Principal Investigator to collaborate with the personnel of the SETI Institute and the NASA-Ames Research center in order to plan and develop space biology research on and in connection with Space Station Freedom; to promote cooperation with the international partners in the space station; to conduct a study on the use of biosensors in space biology research and life support system operation; and to promote space biology research through the initiation of an annual publication 'Advances in Space Biology and Medicine'.

  5. Framing Evolution Discussion Intellectually

    Science.gov (United States)

    Oliveira, Alandeom W.; Cook, Kristin; Buck, Gayle A.

    2011-01-01

    This study examines how a first-year biology teacher facilitates a series of whole-class discussions about evolution during the implementation of a problem-based unit. A communicative theoretical perspective is adopted wherein evolution discussions are viewed as social events that the teacher can frame intellectually (i.e., present or organize as…

  6. Evolution & the Cesarean Section Rate

    Science.gov (United States)

    Walsh, Joseph A.

    2008-01-01

    "Nothing in biology makes sense except in the light of evolution." This was the title of an essay by geneticist Theodosius Dobzhansky writing in 1973. Many causes have been given for the increased Cesarean section rate in developed countries, but biologic evolution has not been one of them. The C-section rate will continue to rise, because the…

  7. Does constructive neutral evolution play an important role in the origin of cellular complexity? Making sense of the origins and uses of biological complexity

    NARCIS (Netherlands)

    D. Speijer

    2011-01-01

    Recently, constructive neutral evolution has been touted as an important concept for the understanding of the emergence of cellular complexity. It has been invoked to help explain the development and retention of, amongst others, RNA splicing, RNA editing and ribosomal and mitochondrial respiratory

  8. Evolution and Christian Faith

    Science.gov (United States)

    Roughgarden, J. E.

    2006-12-01

    My recent book, Evolution and Christian Faith explores how evolutionary biology can be portrayed from the religious perspective of Christianity. The principal metaphors for evolutionary biology---differential success at breeding and random mutation, probably originate with the dawn of agriculture and clearly occur in the Bible. The central narrative of evolutionary biology can be presented using Biblical passages, providing an account of evolution that is inherently friendly to a Christian perspective. Still, evolutionary biology is far from complete, and problematic areas pertain to species in which the concept of an individual is poorly defined, and to species in which the expression of gender and sexuality depart from Darwin's sexual-selection templates. The present- day controversy in the US about teaching evolution in the schools provides an opportunity to engage the public about science education.

  9. The FISH chromosome painting technique in Biological Dosimetry : Evolution and applicability; La Tecnica de Pintado Cromosomico mediante FISH en Dosimetria Biologica: Evolucion y Aplicabilidad

    Energy Technology Data Exchange (ETDEWEB)

    Oteo, M.; Real, A.

    2005-07-01

    The capacity of ionising radiation to induce chromosomal aberrations has been used during decades to assess doses in persons accidentally exposed, giving rise to the discipline Biological Dosimetry. the Biological Dosimetry is a complement to the physical methods of dosimetry and in the situations where those are not available represent the only way to asses the doses received. During decades biological dosimetry has used the dicentric score to determine doses, since a good correlation between in vitro and in vivo irradiation results exists and the background yields are low. However, dicentrics yields decrease with time after irradiation. The translocations and insertions represent stable aberrations what means that they do not decrease in further cell divisions. The development at the end of the 80s of the FISH technique (Fluorescence In Situ Hybridization), represented a great step for the applicability of translocations score for biological dosimetry. In this paper, a review of the FISH chromosome painting technique is presented, addressing the facts that have needed to be solve before its routine use in retrospective dosimetry, as well as the aspects that will need further research in the near future. (Author) 54 refs.

  10. Evolutionary biology of cancer.

    Science.gov (United States)

    Crespi, Bernard; Summers, Kyle

    2005-10-01

    Cancer is driven by the somatic evolution of cell lineages that have escaped controls on replication and by the population-level evolution of genes that influence cancer risk. We describe here how recent evolutionary ecological studies have elucidated the roles of predation by the immune system and competition among normal and cancerous cells in the somatic evolution of cancer. Recent analyses of the evolution of cancer at the population level show how rapid changes in human environments have augmented cancer risk, how strong selection has frequently led to increased cancer risk as a byproduct, and how anticancer selection has led to tumor-suppression systems, tissue designs that slow somatic evolution, constraints on morphological evolution and even senescence itself. We discuss how applications of the tools of ecology and evolutionary biology are poised to revolutionize our understanding and treatment of this disease.

  11. Quantum biological information theory

    CERN Document Server

    Djordjevic, Ivan B

    2016-01-01

    This book is a self-contained, tutorial-based introduction to quantum information theory and quantum biology. It serves as a single-source reference to the topic for researchers in bioengineering, communications engineering, electrical engineering, applied mathematics, biology, computer science, and physics. The book provides all the essential principles of the quantum biological information theory required to describe the quantum information transfer from DNA to proteins, the sources of genetic noise and genetic errors as well as their effects. Integrates quantum information and quantum biology concepts; Assumes only knowledge of basic concepts of vector algebra at undergraduate level; Provides a thorough introduction to basic concepts of quantum information processing, quantum information theory, and quantum biology; Includes in-depth discussion of the quantum biological channel modelling, quantum biological channel capacity calculation, quantum models of aging, quantum models of evolution, quantum models o...

  12. Has Human Evolution Stopped?

    Directory of Open Access Journals (Sweden)

    Alan R. Templeton

    2010-07-01

    Full Text Available It has been argued that human evolution has stopped because humans now adapt to their environment via cultural evolution and not biological evolution. However, all organisms adapt to their environment, and humans are no exception. Culture defines much of the human environment, so cultural evolution has actually led to adaptive evolution in humans. Examples are given to illustrate the rapid pace of adaptive evolution in response to cultural innovations. These adaptive responses have important implications for infectious diseases, Mendelian genetic diseases, and systemic diseases in current human populations. Moreover, evolution proceeds by mechanisms other than natural selection. The recent growth in human population size has greatly increased the reservoir of mutational variants in the human gene pool, thereby enhancing the potential for human evolution. The increase in human population size coupled with our increased capacity to move across the globe has induced a rapid and ongoing evolutionary shift in how genetic variation is distributed within and among local human populations. In particular, genetic differences between human populations are rapidly diminishing and individual heterozygosity is increasing, with beneficial health effects. Finally, even when cultural evolution eliminates selection on a trait, the trait can still evolve due to natural selection on other traits. Our traits are not isolated, independent units, but rather are integrated into a functional whole, so selection on one trait can cause evolution to occur on another trait, sometimes with mildly maladaptive consequences.

  13. Has human evolution stopped?

    Science.gov (United States)

    Templeton, Alan R

    2010-07-01

    It has been argued that human evolution has stopped because humans now adapt to their environment via cultural evolution and not biological evolution. However, all organisms adapt to their environment, and humans are no exception. Culture defines much of the human environment, so cultural evolution has actually led to adaptive evolution in humans. Examples are given to illustrate the rapid pace of adaptive evolution in response to cultural innovations. These adaptive responses have important implications for infectious diseases, Mendelian genetic diseases, and systemic diseases in current human populations. Moreover, evolution proceeds by mechanisms other than natural selection. The recent growth in human population size has greatly increased the reservoir of mutational variants in the human gene pool, thereby enhancing the potential for human evolution. The increase in human population size coupled with our increased capacity to move across the globe has induced a rapid and ongoing evolutionary shift in how genetic variation is distributed within and among local human populations. In particular, genetic differences between human populations are rapidly diminishing and individual heterozygosity is increasing, with beneficial health effects. Finally, even when cultural evolution eliminates selection on a trait, the trait can still evolve due to natural selection on other traits. Our traits are not isolated, independent units, but rather are integrated into a functional whole, so selection on one trait can cause evolution to occur on another trait, sometimes with mildly maladaptive consequences.

  14. Introductory Biology Labs... They Just Aren't Sexy Enough!

    Science.gov (United States)

    Cotner, Sehoya; Gallup, Gordon G., Jr.

    2011-01-01

    The typical introductory biology curriculum includes the nature of science, evolution and genetics. Laboratory activities are designed to engage students in typical subject areas ranging from cell biology and physiology, to ecology and evolution. There are few, if any, laboratory classes exploring the biology and evolution of human sexual…

  15. Hydrogen Evolution from Napiergrass by the Combination of Biological Treatment and a Pt-Loaded TiO2-Photocatalytic Reaction

    Directory of Open Access Journals (Sweden)

    Masahide Yasuda

    2011-12-01

    Full Text Available Ethanol and pentose were produced from lignocellulosic napiergrass by the simultaneous saccharification and fermentation process (SSF using hydrolytic enzyme and S. Cerevisiae. After the ethanol was removed, the pentose solution was subjected to photocatalytic hydrogen evolution with Pt-loaded TiO2 under UV-irradiation. This process converted 100 g of napiergrass into 12.3 g of ethanol and 1.76 g of hydrogen whose total combustion energy of (∆H was 615 kJ. This was close to the ∆H (639 kJ of the pentose (13.6 g and hexose (27.4 g obtained by the cellulose-saccharification of 100 g of napiergrass.

  16. Evolution and social epidemiology.

    Science.gov (United States)

    Nishi, Akihiro

    2015-11-01

    Evolutionary biology, which aims to explain the dynamic process of shaping the diversity of life, has not yet significantly affected thinking in social epidemiology. Current challenges in social epidemiology include understanding how social exposures can affect our biology, explaining the dynamics of society and health, and designing better interventions that are mindful of the impact of exposures during critical periods. I review how evolutionary concepts and tools, such as fitness gradient in cultural evolution, evolutionary game theory, and contemporary evolution in cancer, can provide helpful insights regarding social epidemiology.

  17. [Systems biology of cancer].

    Science.gov (United States)

    Barillot, Emmanuel; Calzone, Laurence; Zinovyev, Andrei

    2009-01-01

    Cancer Systems Biology is now accepted and recognized as a promising field both in biological and clinical research. It relies on a rigorous formalization of regulation networks into precise and unambiguous languages. It provides both detailed and modular views of the complex biological system of interest (which in cancer research is typically an interaction network governing essential cellular events such as proliferation, differentiation, cell death...) in order to facilitate the interpretation of molecular profiles of tumors. The translation of these networks into mathematical models allows prediction of the evolution of the system in time and under certain perturbations. As a result, it can not only propose specific target points for pharmaceutical purposes, but also anticipate the evolution of tumors as well as their classifications. These characteristics emphasize the important role of Systems Biology of Cancer in the future of biomedical research.

  18. Branching processes in biology

    CERN Document Server

    Kimmel, Marek

    2015-01-01

    This book provides a theoretical background of branching processes and discusses their biological applications. Branching processes are a well-developed and powerful set of tools in the field of applied probability. The range of applications considered includes molecular biology, cellular biology, human evolution and medicine. The branching processes discussed include Galton-Watson, Markov, Bellman-Harris, Multitype, and General Processes. As an aid to understanding specific examples, two introductory chapters, and two glossaries are included that provide background material in mathematics and in biology. The book will be of interest to scientists who work in quantitative modeling of biological systems, particularly probabilists, mathematical biologists, biostatisticians, cell biologists, molecular biologists, and bioinformaticians. The authors are a mathematician and cell biologist who have collaborated for more than a decade in the field of branching processes in biology for this new edition. This second ex...

  19. We Recognize Ourselves as Being Similar to Others: Implications of the “Social Brain Hypothesis” for the Biological Evolution of the Intuition of Freedom

    Directory of Open Access Journals (Sweden)

    Eckart Voland

    2007-07-01

    Full Text Available Consistent with and in extension of the “social brain hypothesis,” I discuss the idea that the intuition of free will emerged during the course of primate social evolution. If, as the “social brain hypothesis” alleges, the main selective pressure among primates is on generating social knowledge about one's cooperators and competitors, then it is the knowledge about others and not the knowledge about oneself that is the scarce cognitive resource. It is beneficial to make the others predictable and to form hypotheses about their probable behavioral tendencies. This is done by behavior reading and mind reading and by classifying the recurring stochastic patterns in everyday language as the “will.” Thus, the idea of free will emerged first as a social attribution and not as an introspectively gained insight. The fact that ego applies the idea of freedom also to itself and considers itself to be as free as it considers the social partners to be free, i.e. unpredictable, is in this view a non-selected by-product of social intelligence.

  20. Exploring the kinetic and thermodynamic aspects of four-electron electrochemical reactions: electrocatalysis of oxygen evolution by metal oxides and biological systems.

    Science.gov (United States)

    Wang, Vincent C-C

    2016-08-10

    Finding fundamental and general mechanisms for electrochemical reactions, such as the oxygen evolution reaction (OER) from water and reduction of CO2, plays vital roles in developing the desired electrocatalysts for facilitating solar fuel production. Recently, density functional theory (DFT) calculations have shown that there is a universal scaling relation of adsorption energy between key intermediate species, HO(ad) and HOO(ad), on the surface of metal oxides as OER electrocatalysts. In this paper, a kinetic and thermodynamic model for the four-electron electrochemical reaction based on previous OER mechanisms proposed by DFT calculations is developed to further investigate the electrocatalytic properties over a wide range of metal oxides and photosystem II. The OER activity of metal oxides (i.e. electrocatalytic current) calculated from the DFT-calculated equilibrium potentials with kinetic properties, such as the rate constants for interfacial electron transfer and catalytic turnover, can lead to a volcano-shaped trend that agrees with the results observed in experiments. In addition, the kinetic aspects of the impact on the electrocatalysts are evaluated. Finally, comparing the results of metal oxides and photosystem II, and fitting experimental voltammograms give further insights into kinetic and thermodynamic roles. Here, the general guidelines for designing OER electrocatalysts with unified kinetic and thermodynamic properties are presented.

  1. 进化生物学视角下的创意企业 R & D 能力演化%Evolution of R & D Ability in Creative Enterprises from Perspective of Evolutionary Biology

    Institute of Scientific and Technical Information of China (English)

    刘冰峰; 闫宁宁

    2015-01-01

    针对不同的创意企业R&D活动在规模、技术、文化及生存环境等方面存在的显著差别,从达尔文进化论到中性突变论、超循环论等进化生物学的理论视角出发,探讨了创意企业R&D能力演化的超循环机制,分析了创意企业R&D能力的自我进化博弈。研究表明,市场机会的开拓和挖掘、产品的研制和生产及R&D人才的引进和培养三者构成了创意企业R&D能力的超循环;R&D参与者初始实力的高低对R&D能力的演化没有太大影响,需要企业主动推动R&D能力的有效进化。%Significant difference of different creative enterprises ’ R&D activity in scale, technology, culture, and existing environment was discussed .From the research perspective of Darwin's evolution theory , neutral mutation theory , super cycle the-ory and many other evolutionary biology theories , the super cycle mechanism of R&D ability evolution in creative enterprises was investigated .The self-evolutionary game of R&D ability in creative enterprises was analyzed .Research result shows that the su-per cycle of creative enterprises ’ R&D ability includes the market opportunities open up and mining , product development and production, introduction and cultivation of R&D talent;the initial strength level of R&D participants has not significant effect on R&D ability evolution;it requires enterprises actively promote the effective evolution of R&D ability .

  2. Integrating Functional, Developmental and Evolutionary Biology into Biology Curricula

    Science.gov (United States)

    Haave, Neil

    2012-01-01

    A complete understanding of life involves how organisms are able to function in their environment and how they arise. Understanding how organisms arise involves both their evolution and development. Thus to completely comprehend living things, biology must study their function, development and evolution. Previous proposals for standardized…

  3. Language from a biological perspective

    Indian Academy of Sciences (India)

    Mohinish Shukla

    2005-02-01

    The faculty of language is unique to the human species. This implies that there are human-specific biological changes that lie at the basis of human language. However, it is not clear what the nature of such changes are, and how they could be shaped by evolution. In this paper, emphasis is laid on describing language in a Chomskyan manner, as a mental object. This serves as a standpoint to speculate about the biological basis of the emergence and evolution of language.

  4. Openers for Biology Classes.

    Science.gov (United States)

    Gridley, C. Robert R.

    This teaching guide contains 200 activities that are suitable for openers and demonstrations in biology classes. Details are provided regarding the use of these activities. Some of the broad topics under which the activities are organized include algae, amphibians, bacteria, biologists, crustaceans, dinosaurs, ecology, evolution, flowering plants,…

  5. Early cellular evolution.

    Science.gov (United States)

    Margulis, L.

    1972-01-01

    Study of the evolutionary developments that occurred subsequent to the origin of ancestral cells. Microbial physiology and ecology are potential sharp tools for shaping concepts of microbial evolution. Some popular unjustified assumptions are discussed. It is considered that certain principles derived mainly from the advances of molecular biology can be used to order the natural groups (genera) of extant prokaryotes and their patterns phylogenetically.

  6. Epigenetics: Biology's Quantum Mechanics

    Directory of Open Access Journals (Sweden)

    Richard A Jorgensen

    2011-04-01

    Full Text Available The perspective presented here is that modern genetics is at a similar stage of development as were early formulations of quantum mechanics theory in the 1920's and that in 2010 we are at the dawn of a new revolution in genetics that promises to enrich and deepen our understanding of the gene and the genome. The interrelationships and interdependence of two views of the gene - the molecular biological view and the epigenetic view - are explored, and it is argued that the classical molecular biological view is incomplete without incorporation of the epigenetic perspective and that in a sense the molecular biological view has been evolving to include the epigenetic view. Intriguingly, this evolution of the molecular view toward the broader and more inclusive epigenetic view of the gene has an intriguing, if not precise, parallel in the evolution of concepts of atomic physics from Newtonian mechanics to quantum mechanics that are interesting to consider.

  7. Epigenetics: Biology's Quantum Mechanics.

    Science.gov (United States)

    Jorgensen, Richard A

    2011-01-01

    The perspective presented here is that modern genetics is at a similar stage of development as were early formulations of quantum mechanics theory in the 1920s and that in 2010 we are at the dawn of a new revolution in genetics that promises to enrich and deepen our understanding of the gene and the genome. The interrelationships and interdependence of two views of the gene - the molecular biological view and the epigenetic view - are explored, and it is argued that the classical molecular biological view is incomplete without incorporation of the epigenetic perspective and that in a sense the molecular biological view has been evolving to include the epigenetic view. Intriguingly, this evolution of the molecular view toward the broader and more inclusive epigenetic view of the gene has an intriguing, if not precise, parallel in the evolution of concepts of atomic physics from Newtonian mechanics to quantum mechanics that are interesting to consider.

  8. Kamikazes and cultural evolution.

    Science.gov (United States)

    Allen-Hermanson, Sean

    2017-02-01

    Is cultural evolution needed to explain altruistic selfsacrifice? Some contend that cultural traits (e.g. beliefs, behaviors, and for some "memes") replicate according to selection processes that have "floated free" from biology. One test case is the example of suicide kamikaze attacks in wartime Japan. Standard biological mechanisms-such as reciprocal altruism and kin selection-might not seem to apply here: The suicide pilots did not act on the expectation that others would reciprocate, and they were supposedly sacrificing themselves for country and emperor, not close relatives. Yet an examination of both the historical record and the demands of evolutionary theory suggest the kamikaze phenomenon does not cry out for explanation in terms of a special non-biological selection process. This weakens the case for cultural evolution, and has interesting implications for our understanding of altruistic self-sacrifice.

  9. Practices and Perspectives of College Instructors on Addressing Religious Beliefs When Teaching Evolution

    Science.gov (United States)

    Barnes, M. Elizabeth; Brownell, Sara E.

    2016-01-01

    Evolution is a core concept of biology, and yet many college biology students do not accept evolution because of their religious beliefs. However, we do not currently know how instructors perceive their role in helping students accept evolution or how they address the perceived conflict between religion and evolution when they teach evolution.…

  10. Evolution, epigenetics and cooperation

    Indian Academy of Sciences (India)

    Patrick Bateson

    2014-04-01

    Explanations for biological evolution in terms of changes in gene frequencies refer to outcomes rather than process. Integrating epigenetic studies with older evolutionary theories has drawn attention to the ways in which evolution occurs. Adaptation at the level of the gene is givingway to adaptation at the level of the organism and higher-order assemblages of organisms. These ideas impact on the theories of how cooperation might have evolved. Two of the theories, i.e. that cooperating individuals are genetically related or that they cooperate for self-interested reasons, have been accepted for a long time. The idea that adaptation takes place at the level of groups is much more controversial. However, bringing together studies of development with those of evolution is taking away much of the heat in the debate about the evolution of group behaviour.

  11. All biology is computational biology

    Science.gov (United States)

    2017-01-01

    Here, I argue that computational thinking and techniques are so central to the quest of understanding life that today all biology is computational biology. Computational biology brings order into our understanding of life, it makes biological concepts rigorous and testable, and it provides a reference map that holds together individual insights. The next modern synthesis in biology will be driven by mathematical, statistical, and computational methods being absorbed into mainstream biological training, turning biology into a quantitative science. PMID:28278152

  12. Darwin and Mendel: Evolution and Genetics

    Science.gov (United States)

    Bizzo, Nelio; El-Hani, Charbel N.

    2009-01-01

    Many studies have shown that students' understanding of evolution is low and some sort of historical approach would be necessary in order to allow students to understand the theory of evolution. It is common to present Mendelian genetics to high school students prior to Biological Evolution, having in mind historical and epistemological…

  13. Mainstreaming Caenorhabditis elegans in experimental evolution.

    Science.gov (United States)

    Gray, Jeremy C; Cutter, Asher D

    2014-03-01

    Experimental evolution provides a powerful manipulative tool for probing evolutionary process and mechanism. As this approach to hypothesis testing has taken purchase in biology, so too has the number of experimental systems that use it, each with its own unique strengths and weaknesses. The depth of biological knowledge about Caenorhabditis nematodes, combined with their laboratory tractability, positions them well for exploiting experimental evolution in animal systems to understand deep questions in evolution and ecology, as well as in molecular genetics and systems biology. To date, Caenorhabditis elegans and related species have proved themselves in experimental evolution studies of the process of mutation, host-pathogen coevolution, mating system evolution and life-history theory. Yet these organisms are not broadly recognized for their utility for evolution experiments and remain underexploited. Here, we outline this experimental evolution work undertaken so far in Caenorhabditis, detail simple methodological tricks that can be exploited and identify research areas that are ripe for future discovery.

  14. Culture, Urbanism and Changing Human Biology

    OpenAIRE

    Schell, L M

    2014-01-01

    Anthropologists have long known that human activity driven by culture changes the environment. This is apparent in the archaeological record and through the study of the modern environment. Perhaps the largest change since the paleolithic era is the organization of human populations in cities. New environments can reshape human biology through evolution as shown by the evolution of the hominid lineage. Evolution is not the only process capable of reshaping our biology. Some changes in our hum...

  15. Cultural Evolution and SETI

    Science.gov (United States)

    Dick, S. J.

    2009-12-01

    The Drake Equation for the number of radio communicative technological civilizations in the Galaxy encompasses three components of cosmic evolution: astronomical, biological and cultural. Of these three, cultural evolution totally dominates in terms of the rapidity of its effects. Yet, SETI scientists do not take cultural evolution into account, perhaps for understandable reasons, since cultural evolution is not well-understood even on Earth and is unpredictable in its outcome. But the one certainty for technical civilizations billions, millions, or even thousands of years older than ours is that they will have undergone cultural evolution. Cultural evolution potentially takes place in many directions, but this paper argues that its central driving force is the maintenance, improvement and perpetuation of knowledge and intelligence, and that to the extent intelligence can be improved, it will be improved. Applying this principle to life in the universe, extraterrestrials will have sought the best way to improve their intelligence. One possibility is that they may have long ago advanced beyond flesh-and-blood to artificial intelligence, constituting a postbiological universe. Although this subject has been broached, it has not been given the attention it is due from its foundation in cultural evolution. Nor has the idea of a postbiological universe been carried to its logical conclusion, including a careful analysis of the implications for SETI. SETI scientists, social scientists, and experts in AI should consider the strengths and weaknesses of this new paradigm.

  16. Prolegomenon to patterns in evolution.

    Science.gov (United States)

    Kauffman, Stuart A

    2014-09-01

    Despite Darwin, we remain children of Newton and dream of a grand theory that is epistemologically complete and would allow prediction of the evolution of the biosphere. The main purpose of this article is to show that this dream is false, and bears on studying patterns of evolution. To do so, I must justify the use of the word "function" in biology, when physics has only happenings. The concept of "function" lifts biology irreducibly above physics, for as we shall see, we cannot prestate the ever new biological functions that arise and constitute the very phase space of evolution. Hence, we cannot mathematize the detailed becoming of the biosphere, nor write differential equations for functional variables we do not know ahead of time, nor integrate those equations, so no laws "entail" evolution. The dream of a grand theory fails. In place of entailing laws, I propose a post-entailing law explanatory framework in which Actuals arise in evolution that constitute new boundary conditions that are enabling constraints that create new, typically unprestatable, adjacent possible opportunities for further evolution, in which new Actuals arise, in a persistent becoming. Evolution flows into a typically unprestatable succession of adjacent possibles. Given the concept of function, the concept of functional closure of an organism making a living in its world becomes central. Implications for patterns in evolution include historical reconstruction, and statistical laws such as the distribution of extinction events, or species per genus, and the use of formal cause, not efficient cause, laws.

  17. The apoptotic machinery as a biological complex system: analysis of its omics and evolution, identification of candidate genes for fourteen major types of cancer, and experimental validation in CML and neuroblastoma

    Directory of Open Access Journals (Sweden)

    Li Destri Giovanni

    2009-04-01

    Full Text Available Abstract Background Apoptosis is a critical biological phenomenon, executed under the guidance of the Apoptotic Machinery (AM, which allows the physiologic elimination of terminally differentiated, senescent or diseased cells. Because of its relevance to BioMedicine, we have sought to obtain a detailed characterization of AM Omics in Homo sapiens, namely its Genomics and Evolution, Transcriptomics, Proteomics, Interactomics, Oncogenomics, and Pharmacogenomics. Methods This project exploited the methodology commonly used in Computational Biology (i.e., mining of many omics databases of the web as well as the High Throughput biomolecular analytical techniques. Results In Homo sapiens AM is comprised of 342 protein-encoding genes (possessing either anti- or pro-apoptotic activity, or a regulatory function and 110 MIR-encoding genes targeting them: some have a critical role within the system (core AM nodes, others perform tissue-, pathway-, or disease-specific functions (peripheral AM nodes. By overlapping the cancer type-specific AM mutation map in the fourteen most frequent cancers in western societies (breast, colon, kidney, leukaemia, liver, lung, neuroblastoma, ovary, pancreas, prostate, skin, stomach, thyroid, and uterus to their transcriptome, proteome and interactome in the same tumour type, we have identified the most prominent AM molecular alterations within each class. The comparison of the fourteen mutated AM networks (both protein- as MIR-based has allowed us to pinpoint the hubs with a general and critical role in tumour development and, conversely, in cell physiology: in particular, we found that some of these had already been used as targets for pharmacological anticancer therapy. For a better understanding of the relationship between AM molecular alterations and pharmacological induction of apoptosis in cancer, we examined the expression of AM genes in K562 and SH-SY5Y after anticancer treatment. Conclusion We believe that our data

  18. Biology-Derived Algorithms in Engineering Optimization

    CERN Document Server

    Yang, Xin-She

    2010-01-01

    Biology-derived algorithms are an important part of computational sciences, which are essential to many scientific disciplines and engineering applications. Many computational methods are derived from or based on the analogy to natural evolution and biological activities, and these biologically inspired computations include genetic algorithms, neural networks, cellular automata, and other algorithms.

  19. Chemical and biological evolution in space

    Science.gov (United States)

    Greenberg, J. M.; Weber, P.; Schutte, W.

    1984-01-01

    The formation of organic molecules in interstellar dust grains and the survival of bacterial spores in a space environment are examined, summarizing the results of experimental investigations and theoretical calculations. The interstellar medium is characterized; the production of organic yellow-stuff residues on the mantles of dust grains in molecular clouds by UV radiation is explained; an IR absorption spectrum toward a Galactic-center source is shown to confirm the presence of such residues; and the mass of such abiotically produced complex organic molecules in the Galaxy is estimated as at least 10 to the 7th solar mass, or 0.1 percent of the mass in the Galaxy. This finding is considered significant for the prebiotic chemistry of the earth, since comets containing large amounts of interstellar dust may have impacted the earth many times during comet showers in the early solar system. UV-irradiation experiments on bacterial spores show that initial exposures to solar UV, not interstellar survival, is the main factor rendering theries of panspermia questionable.

  20. Cell Division and Evolution of Biological Tissues

    Science.gov (United States)

    Rivier, Nicolas; Arcenegui-Siemens, Xavier; Schliecker, Gudrun

    A tissue is a geometrical, space-filling, random cellular network; it remains in this steady state while individual cells divide. Cell division (fragmentation) is a local, elementary topological transformation which establishes statistical equilibrium of the structure. Statistical equilibrium is characterized by observable relations (Lewis, Aboav) between cell shapes, sizes and those of their neighbours, obtained through maximum entropy and topological correlation extending to nearest neighbours only, i.e. maximal randomness. For a two-dimensional tissue (epithelium), the distribution of cell shapes and that of mother and daughter cells can be obtained from elementary geometrical and physical arguments, except for an exponential factor favouring division of larger cells, and exponential and combinatorial factors encouraging a most symmetric division. The resulting distributions are very narrow, and stationarity severely restricts the range of an adjustable structural parameter

  1. Spherule Beds 3.47-3.24 Billion Years Old in the Barberton Greenstone Belt, South Africa: A Record of Large Meteorite Impacts and Their Influence on Early Crustal and Biological Evolution

    Science.gov (United States)

    Lowe, Donald R.; Byerly, Gary R.; Kyte, Frank T.; Shukolyukov, Alexander; Asaro, Frank; Krull, Alexander

    2003-01-01

    Four layers, S1-S4, containing sand-sized spherical particles formed as a result of large meteorite impacts, occur in 3.47-3.24 Ga rocks of the Barberton Greenstone Belt, South Africa. Ir levels in S3 and S4 locally equal or exceed chondritic values but in other sections are at or only slightly above background. Most spherules are inferred to have formed by condensation of impact-produced rock vapor clouds, although some may represent ballistically ejected liquid droplets. Extreme Ir abundances and heterogeneity may reflect element fractionation during spherule formation, hydraulic fractionation during deposition, and/or diagenetic and metasomatic processes. Deposition of S1, S2, and S3 was widely influenced by waves and/or currents interpreted to represent impact-generated tsunamis, and S1 and S2 show multiple graded layers indicating the passage of two or more wave trains. These tsunamis may have promoted mixing within a globally stratified ocean, enriching surface waters in nutrients for biological communities. S2 and S3 mark the transition from the 300-million-year-long Onverwacht stage of predominantly basaltic and komatiitic volcanism to the late orogenic stage of greenstone belt evolution, suggesting that regional and possibly global tectonic reorganization resulted from these large impacts. These beds provide the oldest known direct record of terrestrial impacts and an opportunity to explore their influence on early life, crust, ocean, and atmosphere. The apparent presence of impact clusters at 3.26-3.24 Ga and approx. 2.65-2.5 Ga suggests either spikes in impact rates during the Archean or that the entire Archean was characterized by terrestrial impact rates above those currently estimated from the lunar cratering record.

  2. Viral quasispecies evolution

    OpenAIRE

    Domingo, Esteban; Sheldon, Julie; Perales, Celia

    2012-01-01

    Summary: Evolution of RNA viruses occurs through disequilibria of collections of closely related mutant spectra or mutant clouds termed viral quasispecies. Here we review the origin of the quasispecies concept and some biological implications of quasispecies dynamics. Two main aspects are addressed: (i) mutant clouds as reservoirs of phenotypic variants for virus adaptability and (ii) the internal interactions that are established within mutant spectra that render a virus ensemble the unit of...

  3. Ethics, evolution and culture.

    Science.gov (United States)

    Mesoudi, Alex; Danielson, Peter

    2008-08-01

    Recent work in the fields of evolutionary ethics and moral psychology appears to be converging on a single empirically- and evolutionary-based science of morality or ethics. To date, however, these fields have failed to provide an adequate conceptualisation of how culture affects the content and distribution of moral norms. This is particularly important for a large class of moral norms relating to rapidly changing technological or social environments, such as norms regarding the acceptability of genetically modified organisms. Here we suggest that a science of morality/ethics can benefit from adopting a cultural evolution or gene-culture coevolution approach, which treats culture as a second, separate evolutionary system that acts in parallel to biological/genetic evolution. This cultural evolution approach brings with it a set of established theoretical concepts (e.g. different cultural transmission mechanisms) and empirical methods (e.g. evolutionary game theory) that can significantly improve our understanding of human morality.

  4. Second Symposium on Chemical Evolution and the Origin of Life

    Science.gov (United States)

    Devincenzi, D. L. (Editor); model. (Editor)

    1986-01-01

    Recent findings by NASA Exobiology investigators are reported. Scientific papers are presented in the following areas: cosmic evolution of biogenic compounds, prebiotic evolution (planetary and molecular), early evolution of life (biological and geochemical), evolution of advanced life, solar system exploration, and the Search for Extraterrestrial Intelligence (SETI).

  5. Evolution Strategies in Optimization Problems

    CERN Document Server

    Cruz, Pedro A F

    2007-01-01

    Evolution Strategies are inspired in biology and part of a larger research field known as Evolutionary Algorithms. Those strategies perform a random search in the space of admissible functions, aiming to optimize some given objective function. We show that simple evolution strategies are a useful tool in optimal control, permitting to obtain, in an efficient way, good approximations to the solutions of some recent and challenging optimal control problems.

  6. Cultural commons and cultural evolution

    OpenAIRE

    Giangiacomo Bravo

    2010-01-01

    Culture evolves following a process that is akin to biological evolution, although with some significant differences. At the same time culture has often a collective good value for human groups. This paper studies culture in an evolutionary perspective, with a focus on the implications of group definition for the coexistence of different cultures. A model of cultural evolution is presented where agents interacts in an artificial environment. The belonging to a specific memetic group is a majo...

  7. A Review of Research Instruments Assessing Levels of Student Acceptance of Evolution

    Science.gov (United States)

    Yasri, Pratchayapong

    2014-01-01

    Darwin's theory of evolution by means of natural selection, called evolution for short, is perceived as a unifying theme in biology, forming a major part of all biology syllabuses. It is reported that student acceptance of evolution associates with conceptual understandings of biological contents, nature of science, as well as motivations to…

  8. [Biological weapons].

    Science.gov (United States)

    Kerwat, K; Becker, S; Wulf, H; Densow, D

    2010-08-01

    Biological weapons are weapons of mass destruction that use pathogens (bacteria, viruses) or the toxins produced by them to target living organisms or to contaminate non-living substances. In the past, biological warfare has been repeatedly used. Anthrax, plague and smallpox are regarded as the most dangerous biological weapons by various institutions. Nowadays it seems quite unlikely that biological warfare will be employed in any military campaigns. However, the possibility remains that biological weapons may be used in acts of bioterrorism. In addition all diseases caused by biological weapons may also occur naturally or as a result of a laboratory accident. Risk assessment with regard to biological danger often proves to be difficult. In this context, an early identification of a potentially dangerous situation through experts is essential to limit the degree of damage.

  9. Schumpeter's Evolution

    DEFF Research Database (Denmark)

    Andersen, Esben Sloth

    reworking of his basic theory of economic evolution in Development from 1934, and this reworking was continued in Cycles from 1939. Here Schumpeter also tried to handle the statistical and historical evidence on the waveform evolution of the capitalist economy. Capitalism from 1942 modified the model...

  10. Fourth Symposium on Chemical Evolution and the Origin and Evolution of Life

    Science.gov (United States)

    Wharton, Robert A., Jr. (Editor); Andersen, Dale T. (Editor); Bzik, Sara E. (Editor); Rummel, John D. (Editor)

    1991-01-01

    This symposium was held at the NASA Ames Research Center, Moffett Field, California, July 24-27, 1990. The NASA exobiology investigators reported their recent research findings. Scientific papers were presented in the following areas: cosmic evolution of biogenic compounds, prebiotic evolution (planetary and molecular), early evolution of life (biological and geochemical), evolution of advanced life, solar system exploration, and the Search for Extraterrestrial Intelligence (SETI).

  11. 合成生物学:工程伦理的实践悖论——从合成生物学对生命、自然及进化的挑战谈起%Synthetic Biology: the Practice Paradox of Engineering Ethics Starting from Challenges Which Synthetic Biology Brings to Life, Nature and Evolution

    Institute of Scientific and Technical Information of China (English)

    程晨; 徐飞

    2012-01-01

    Synthetic biology aims at the design and construction of biological systems not found in nature, and being applied to human practice. However, this new branch challenges life, nature and evolution, which makes itself face the dilemma of paradox in practice. Actually, synthetic biology challenges the traditional conception of life, destroys the natural and uses human selection and purpose-oriented evolution to replace the natural evolution. All these rational technical operations lead to the irrationality of its existence, but we can see the rationality of its application in science and technology from the irrationality, There is no doubt that to investigate the practice paradox of synthetic biology has significant philosophical enlightenment to the understanding of the practice value of engineering ethics.%合成生物学致力于设计和建构自然界不存在的生物系统并将其运用于人类实践,这一新学科正对生命、自然及进化发起了挑战,也导致其在实践中面临悖论发展的困境。合成生物学挑战了传统的生命概念,摧毁了自然性,利用人为选择和有目的的进化取代了自然进化。所有这些合理的技术操作都导致了其存在的不合理性;而从其不合理性中,又能看到其科技应用的合理性。考察合成生物学的这种实践悖论特性,对于深入理解工程伦理的实践价值无疑具有重要的哲学启迪。

  12. Evolution--A Topic for Interdisciplinary Study.

    Science.gov (United States)

    Stall, Pat; Keating, Joe

    1990-01-01

    Outlines an award-winning interdisciplinary unit of study (used in biology and English classrooms) that combines literature, mythology, religious history relating to origins, and Charles Darwin's theory of evolution. (RS)

  13. Stellar evolution

    CERN Document Server

    Meadows, A J

    2013-01-01

    Stellar Evolution, Second Edition covers the significant advances in the understanding of birth, life, and death of stars.This book is divided into nine chapters and begins with a description of the characteristics of stars according to their brightness, distance, size, mass, age, and chemical composition. The next chapters deal with the families, structure, and birth of stars. These topics are followed by discussions of the chemical composition and the evolution of main-sequence stars. A chapter focuses on the unique features of the sun as a star, including its evolution, magnetic fields, act

  14. Biological trade and markets.

    Science.gov (United States)

    Hammerstein, Peter; Noë, Ronald

    2016-02-01

    Cooperation between organisms can often be understood, like trade between merchants, as a mutually beneficial exchange of services, resources or other 'commodities'. Mutual benefits alone, however, are not sufficient to explain the evolution of trade-based cooperation. First, organisms may reject a particular trade if another partner offers a better deal. Second, while human trade often entails binding contracts, non-human trade requires unwritten 'terms of contract' that 'self-stabilize' trade and prevent cheating even if all traders strive to maximize fitness. Whenever trading partners can be chosen, market-like situations arise in nature that biologists studying cooperation need to account for. The mere possibility of exerting partner choice stabilizes many forms of otherwise cheatable trade, induces competition, facilitates the evolution of specialization and often leads to intricate forms of cooperation. We discuss selected examples to illustrate these general points and review basic conceptual approaches that are important in the theory of biological trade and markets. Comparing these approaches with theory in economics, it turns out that conventional models-often called 'Walrasian' markets-are of limited relevance to biology. In contrast, early approaches to trade and markets, as found in the works of Ricardo and Cournot, contain elements of thought that have inspired useful models in biology. For example, the concept of comparative advantage has biological applications in trade, signalling and ecological competition. We also see convergence between post-Walrasian economics and biological markets. For example, both economists and biologists are studying 'principal-agent' problems with principals offering jobs to agents without being sure that the agents will do a proper job. Finally, we show that mating markets have many peculiarities not shared with conventional economic markets. Ideas from economics are useful for biologists studying cooperation but need

  15. Evolution of Oxygenic Photosynthesis

    Science.gov (United States)

    Fischer, Woodward W.; Hemp, James; Johnson, Jena E.

    2016-06-01

    The origin of oxygenic photosynthesis was the most important metabolic innovation in Earth history. It allowed life to generate energy and reducing power directly from sunlight and water, freeing it from the limited resources of geochemically derived reductants. This greatly increased global primary productivity and restructured ecosystems. The release of O2 as an end product of water oxidation led to the rise of oxygen, which dramatically altered the redox state of Earth's atmosphere and oceans and permanently changed all major biogeochemical cycles. Furthermore, the biological availability of O2 allowed for the evolution of aerobic respiration and novel biosynthetic pathways, facilitating much of the richness we associate with modern biology, including complex multicellularity. Here we critically review and synthesize information from the geological and biological records for the origin and evolution of oxygenic photosynthesis. Data from both of these archives illustrate that this metabolism first appeared in early Paleoproterozoic time and, despite its biogeochemical prominence, is a relatively late invention in the context of our planet's history.

  16. Is synthetic biology mechanical biology?

    Science.gov (United States)

    Holm, Sune

    2015-12-01

    A widespread and influential characterization of synthetic biology emphasizes that synthetic biology is the application of engineering principles to living systems. Furthermore, there is a strong tendency to express the engineering approach to organisms in terms of what seems to be an ontological claim: organisms are machines. In the paper I investigate the ontological and heuristic significance of the machine analogy in synthetic biology. I argue that the use of the machine analogy and the aim of producing rationally designed organisms does not necessarily imply a commitment to mechanical biology. The ideal of applying engineering principles to biology is best understood as expressing recognition of the machine-unlikeness of natural organisms and the limits of human cognition. The paper suggests an interpretation of the identification of organisms with machines in synthetic biology according to which it expresses a strategy for representing, understanding, and constructing living systems that are more machine-like than natural organisms.

  17. Language as a biological entity

    Institute of Scientific and Technical Information of China (English)

    张舒音

    2010-01-01

    @@ Nowadays, the metaphor of "languageas abiological entity"claimed by some linguists being used widely has become a hot issue. Language and biological entity indeed share a lot of similarities,specifically,the life cycle of languages and the process of the language evolution and the spread of languages.

  18. Teaching the Broad, Interdisciplinary Impact of Evolution

    Science.gov (United States)

    Benson, David; Atlas, Pierre; Haberski, Raymond; Higgs, Jamie; Kiley, Patrick; Maxwell, Michael, Jr.; Mirola, William; Norton, Jamey

    2009-01-01

    As perhaps the most encompassing idea in biology, evolution has impacted not only science, but other academic disciplines as well. The broad, interdisciplinary impact of evolution was the theme of a course taught at Marian College, Indianapolis, Indiana in 2002, 2004, and 2006. Using a strategy that could be readily adopted at other institutions,…

  19. Cultural evolution as a nonstationary stochastic process

    DEFF Research Database (Denmark)

    Nicholson, Arwen; Sibani, Paolo

    2016-01-01

    We present an individual based model of cultural evolution, where interacting agents are coded by binary strings standing for strategies for action, blueprints for products or attitudes and beliefs. The model is patterned on an established model of biological evolution, the Tangled Nature Model (...... qualitatively reproduce the flurry of cultural activity which follows a disruptive innovation....

  20. Investigating Evolution with Living Plants.

    Science.gov (United States)

    Schlessman, Mark A.

    1997-01-01

    Describes two investigative labs that use live plants to illustrate important biological principles, include quantitative analysis, and require very little equipment. Each lab is adaptable to a variety of class sizes, course contents, and student backgrounds. Topics include the evolution of flower size in Mimulus and pollination of Brassicas. (DDR)

  1. Computational biology

    DEFF Research Database (Denmark)

    Hartmann, Lars Røeboe; Jones, Neil; Simonsen, Jakob Grue

    2011-01-01

    Computation via biological devices has been the subject of close scrutiny since von Neumann’s early work some 60 years ago. In spite of the many relevant works in this field, the notion of programming biological devices seems to be, at best, ill-defined. While many devices are claimed or proved t...

  2. Biological Oceanography

    Science.gov (United States)

    Dyhrman, Sonya

    2004-10-01

    The ocean is arguably the largest habitat on the planet, and it houses an astounding array of life, from microbes to whales. As a testament to this diversity and its importance, the discipline of biological oceanography spans studies of all levels of biological organization, from that of single genes, to organisms, to their population dynamics. Biological oceanography also includes studies on how organisms interact with, and contribute to, essential global processes. Students of biological oceanography are often as comfortable looking at satellite images as they are electron micrographs. This diversity of perspective begins the textbook Biological Oceanography, with cover graphics including a Coastal Zone Color Scanner image representing chlorophyll concentration, an electron micrograph of a dinoflagellate, and a photograph of a copepod. These images instantly capture the reader's attention and illustrate some of the different scales on which budding oceanographers are required to think. Having taught a core graduate course in biological oceanography for many years, Charlie Miller has used his lecture notes as the genesis for this book. The text covers the subject of biological oceanography in a manner that is targeted to introductory graduate students, but it would also be appropriate for advanced undergraduates.

  3. Quantum Biology

    Directory of Open Access Journals (Sweden)

    Alessandro Sergi

    2009-06-01

    Full Text Available A critical assessment of the recent developmentsof molecular biology is presented.The thesis that they do not lead to a conceptualunderstanding of life and biological systems is defended.Maturana and Varela's concept of autopoiesis is briefly sketchedand its logical circularity avoided by postulatingthe existence of underlying living processes,entailing amplification from the microscopic to the macroscopic scale,with increasing complexity in the passage from one scale to the other.Following such a line of thought, the currently accepted model of condensed matter, which is based on electrostatics and short-ranged forces,is criticized. It is suggested that the correct interpretationof quantum dispersion forces (van der Waals, hydrogen bonding, and so onas quantum coherence effects hints at the necessity of includinglong-ranged forces (or mechanisms for them incondensed matter theories of biological processes.Some quantum effects in biology are reviewedand quantum mechanics is acknowledged as conceptually important to biology since withoutit most (if not all of the biological structuresand signalling processes would not even exist. Moreover, it is suggested that long-rangequantum coherent dynamics, including electron polarization,may be invoked to explain signal amplificationprocess in biological systems in general.

  4. Foldit Biology

    Science.gov (United States)

    2015-07-31

    Report 8/1/2013-7/31/2015 4. TITLE AND SUBTITLE Sa. CONTRACT NUMBER Foldit Biology NOOO 14-13-C-0221 Sb. GRANT NUMBER N/A Sc. PROGRAM ELEMENT...Include area code) Unclassified Unclassified Unclassified (206) 616-2660 Zoran Popović Foldit Biology (Task 1, 2, 3, 4) Final Report...Period Covered by the Report August 1, 2013 – July 31, 2015 Date of Report: July 31, 2015 Project Title: Foldit Biology Contract Number: N00014-13

  5. Sociodemographic aspect of society evolution

    Directory of Open Access Journals (Sweden)

    Raisa Viktorovna Nifanova

    2013-12-01

    Full Text Available In the article, the authors have classified theories of human aging, having emphasized the theory of «cellular death» on the basis of generalization of an extensive theoretical and empirical material of domestic and foreign researchers. The main theories of specific duration of human life, the biological and social and economic criteria and health factors of causes of death and longevity are briefly presented. The achievements of the genetics of a human body aging are discussed. In the article, the author stopped on a problem of the human genofond stability and obvious delay of its biological evolution in the historical development. Despite a deep socialization of humanity, people remains in captivity of biological life, obey all the laws of the biological organization including those that keep it and provide it to following generations. The biological factors influencing reproduction of the population, unlike social factors, are more stable in time. Various socioeconomic and physiographic conditions interacted for a long time with biological factors, determine a certain life expectancy. In the modern conditions for forward development of society, the special value gets a question of the human potential realization — gold fund of of manufacture, science, culture. With a «century of biology» which starts with the development of molecular biology, genetics, biological cybernetics, the science has new opportunities for effective adaptation of human to new conditions

  6. Galaxy Evolution

    Science.gov (United States)

    Matteucci, F.

    We review both the observational and theoretical constraints on the evolution of the abundances of heavy elements in gas and stars in galaxies of different morphological type. The main aim of this work is to document the progress made in our understanding of the physical processes regulating the chemical evolution of galaxies during the last sixteen years since the appearance, in this same journal (volume 5, page 287), of the well know review of Beatrice Tinsley, to whom I dedicate this paper. Finally, this article is addressed particularly to readers who do not actively work on galactic chemical evolution and who might use it as a cook book where the main ingredients are discussed and useful recipes can be found.

  7. Research trends in radiobiology since 40 years. a new approach: the enzymatic repair function of DNA, internal factor in evolution of biological systems under irradiation; Etude des tendances des recherches en radiologie depuis 40 ans. Une nouvelle voie de recherche: la fonction de reparation enzymatique de l'ADN, facteur interne d'evolution des systemes biologiques sous rayonnement

    Energy Technology Data Exchange (ETDEWEB)

    Mouton, R. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1968-07-01

    In the first part of the report, the author attempts to draw an historical scheme of successive research working hypotheses in radiobiology since 1924. Less than a generation ago the effect of radiation exposure were viewed as being direct, immediate, irreparable and unmodifiable. Now it is generally accepted that radiation lesion can also be indirect, delayed, reparable and often modified with appropriate chemical or biochemical treatment. It was however in 1962-1964 that came the decisive breakthrough in radiobiology with the discovery that the cell possesses a natural active self-defense mechanism against whatever stress would affect the integrity of the genetic message contained in the DNA structure itself. The existence of what could be considered as a fourth DNA function i.e. self-repair by enzymatic action under genetic control-brings at least to radiobiology the missing molecular biology basis it needed to get out of its 'phenomenological night' after abandon of the generalization of Lea's theory through lack of experimental evidence. In the second part, which is a prospective one, the author tries to set an enlarged synthesis considering the possible role of DNA repair system not only in cell survival - in presence or absence of dose modifiers or mutagens - but also in the artificial and natural evolution of biological system exposed to sub-lethal doses of radiation. Most recent data from the literature fit well with what must be still considered as a general working hypothesis. Studies dealing with phenotypic and genotypic characters linked with the acquisition of gamma and UV radiation resistance in 'Escherichia coli K12' has been started by the author, in collaboration with O. Tremeau, in order to bring a new experimental contribution in this respect. (author) [French] Dans la premiere partie, l'auteur tente de retracer l'historique des hypotheses successives qui ont jalonne les avances de la radiobiologie depuis 1924

  8. Darwinian evolution in the light of genomics.

    Science.gov (United States)

    Koonin, Eugene V

    2009-03-01

    Comparative genomics and systems biology offer unprecedented opportunities for testing central tenets of evolutionary biology formulated by Darwin in the Origin of Species in 1859 and expanded in the Modern Synthesis 100 years later. Evolutionary-genomic studies show that natural selection is only one of the forces that shape genome evolution and is not quantitatively dominant, whereas non-adaptive processes are much more prominent than previously suspected. Major contributions of horizontal gene transfer and diverse selfish genetic elements to genome evolution undermine the Tree of Life concept. An adequate depiction of evolution requires the more complex concept of a network or 'forest' of life. There is no consistent tendency of evolution towards increased genomic complexity, and when complexity increases, this appears to be a non-adaptive consequence of evolution under weak purifying selection rather than an adaptation. Several universals of genome evolution were discovered including the invariant distributions of evolutionary rates among orthologous genes from diverse genomes and of paralogous gene family sizes, and the negative correlation between gene expression level and sequence evolution rate. Simple, non-adaptive models of evolution explain some of these universals, suggesting that a new synthesis of evolutionary biology might become feasible in a not so remote future.

  9. Representing Evolution

    DEFF Research Database (Denmark)

    Hedin, Gry

    2012-01-01

    . This article discusses Willumsen's etching in the context of evolutionary theory, arguing that Willumsen is a rare example of an artist who not only let the theory of evolution fuel his artistic imagination, but also concerned himself with a core issue of the theory, namely to what extent it could be applied...

  10. Continuous "in vitro" Evolution of a Ribozyme Ligase: A Model Experiment for the Evolution of a Biomolecule

    Science.gov (United States)

    Ledbetter, Michael P.; Hwang, Tony W.; Stovall, Gwendolyn M.; Ellington, Andrew D.

    2013-01-01

    Evolution is a defining criterion of life and is central to understanding biological systems. However, the timescale of evolutionary shifts in phenotype limits most classroom evolution experiments to simple probability simulations. "In vitro" directed evolution (IVDE) frequently serves as a model system for the study of Darwinian…

  11. Ludwig von Bertalanffy's organismic view on the theory of evolution.

    Science.gov (United States)

    Drack, Manfred

    2015-03-01

    Ludwig von Bertalanffy was a key figure in the advancement of theoretical biology. His early considerations already led him to recognize the necessity of considering the organism as a system, as an organization of parts and processes. He termed the resulting research program organismic biology, which he extended to all basic questions of biology and almost all areas of biology, hence also to the theory of evolution. This article begins by outlining the rather unknown (because often written in German) research of Bertalanffy in the field of theoretical biology. The basics of the organismic approach are then described. This is followed by Bertalanffy's considerations on the theory of evolution, in which he used methods from theoretical biology and then introduced his own, organismic, view on evolution, leading to the demand for finding laws of evolution. Finally, his view on the concept of homology is presented.

  12. Cultural evolution: implications for understanding the human language faculty and its evolution.

    Science.gov (United States)

    Smith, Kenny; Kirby, Simon

    2008-11-12

    Human language is unique among the communication systems of the natural world: it is socially learned and, as a consequence of its recursively compositional structure, offers open-ended communicative potential. The structure of this communication system can be explained as a consequence of the evolution of the human biological capacity for language or the cultural evolution of language itself. We argue, supported by a formal model, that an explanatory account that involves some role for cultural evolution has profound implications for our understanding of the biological evolution of the language faculty: under a number of reasonable scenarios, cultural evolution can shield the language faculty from selection, such that strongly constraining language-specific learning biases are unlikely to evolve. We therefore argue that language is best seen as a consequence of cultural evolution in populations with a weak and/or domain-general language faculty.

  13. Teaching Evolution: A Heuristic Study of Personal and Cultural Dissonance

    Science.gov (United States)

    Grimes, Larry G.

    Darwinian evolution is a robustly supported scientific theory. Yet creationists continue to challenge its teaching in American public schools. Biology teachers in all 50 states are responsible for teaching science content standards that include evolution. As products of their backgrounds and affiliations teachers bring personal attitudes and beliefs to their teaching. The purpose of this study was to explore how biology teachers perceive, describe, and value their teaching of evolution. This research question was explored through a heuristic qualitative methodology. Eight veteran California high school biology teachers were queried as to their beliefs, perceptions, experiences and practices of teaching evolution. Both personal and professional documents were collected. Data was presented in the form of biographical essays that highlight teachers' backgrounds, experiences, perspectives and practices of teaching evolution. Of special interest was how they describe pressure over teaching evolution during a decade of standards and No Child Left Behind high-stakes testing mandates. Five common themes emerged. Standards have increased the overall amount of evolution that is taught. High-stakes testing has decreased the depth at which evolution is taught. Teacher belief systems strongly influence how evolution is taught. Fear of creationist challenges effect evolution teaching strategies. And lastly, concern over the potential effects of teaching evolution on student worldviews was mixed. Three categories of teacher concern over the potential impact of evolution on student worldviews were identified: Concerned, Strategist, and Carefree. In the final analysis teacher beliefs and attitudes still appeared to he the most important factor influencing how evolution is taught.

  14. Biological preconcentrator

    Science.gov (United States)

    Manginell, Ronald P.; Bunker, Bruce C.; Huber, Dale L.

    2008-09-09

    A biological preconcentrator comprises a stimulus-responsive active film on a stimulus-producing microfabricated platform. The active film can comprise a thermally switchable polymer film that can be used to selectively absorb and desorb proteins from a protein mixture. The biological microfabricated platform can comprise a thin membrane suspended on a substrate with an integral resistive heater and/or thermoelectric cooler for thermal switching of the active polymer film disposed on the membrane. The active polymer film can comprise hydrogel-like polymers, such as poly(ethylene oxide) or poly(n-isopropylacrylamide), that are tethered to the membrane. The biological preconcentrator can be fabricated with semiconductor materials and technologies.

  15. Thermodynamical Arguments Against Evolution

    Science.gov (United States)

    Rosenhouse, Jason

    2017-02-01

    The argument that the second law of thermodynamics contradicts the theory of evolution has recently been revived by anti-evolutionists. In its basic form, the argument asserts that whereas evolution implies that there has been an increase in biological complexity over time, the second law, a fundamental principle of physics, shows this to be impossible. Scientists have responded primarily by noting that the second law does not rule out increases in complexity in open systems, and since the Earth receives energy from the Sun, it is an open system. This reply is correct as far as it goes, and it adequately rebuts the most crude versions of the second law argument. However, it is insufficient against more sophisticated versions, and it leaves many relevant aspects of thermodynamics unexplained. We shall consider the history of the argument, explain the nuances various anti-evolution writers have brought to it, and offer thorough explanations for why the argument is fallacious. We shall emphasize in particular that the second law is best viewed as a mathematical statement. Since anti-evolutionists never make use of the mathematical structure of thermodynamics, invocations of the second law never contribute anything substantive to their discourse.

  16. Which Beak Fits the Bill? An Activity Examining Adaptation, Natural Selection and Evolution

    Science.gov (United States)

    Darling, Randi

    2014-01-01

    Evolution is a unifying concept within biology. In fact, Dobzhansky, a noted evolutionary biologist, argued, "Nothing in biology makes sense except in the light of evolution" (Dobzhansky, 1973). However, often students have misconceptions about evolution. There are a number of available activities where students use tools (representing…

  17. Biology Notes.

    Science.gov (United States)

    School Science Review, 1981

    1981-01-01

    Outlines a variety of laboratory procedures, techniques, and materials including construction of a survey frame for field biology, a simple tidal system, isolation and applications of plant protoplasts, tropisms, teaching lung structure, and a key to statistical methods for biologists. (DS)

  18. (Biological dosimetry)

    Energy Technology Data Exchange (ETDEWEB)

    Preston, R.J.

    1990-12-17

    The traveler attended the 1st International Conference on Biological Dosimetry in Madrid, Spain. This conference was organized to provide information to a general audience of biologists, physicists, radiotherapists, industrial hygiene personnel and individuals from related fields on the current ability of cytogenetic analysis to provide estimates of radiation dose in cases of occupational or environmental exposure. There is a growing interest in Spain in biological dosimetry because of the increased use of radiation sources for medical and occupational uses, and with this the anticipated and actual increase in numbers of overexposure. The traveler delivered the introductory lecture on Biological Dosimetry: Mechanistic Concepts'' that was intended to provide a framework by which the more applied lectures could be interpreted in a mechanistic way. A second component of the trip was to provide advice with regard to several recent cases of overexposure that had been or were being assessed by the Radiopathology and Radiotherapy Department of the Hospital General Gregorio Maranon'' in Madrid. The traveler had provided information on several of these, and had analyzed cells from some exposed or purportedly exposed individuals. The members of the biological dosimetry group were referred to individuals at REACTS at Oak Ridge Associated Universities for advice on follow-up treatment.

  19. Marine Biology

    Science.gov (United States)

    Dewees, Christopher M.; Hooper, Jon K.

    1976-01-01

    A variety of informational material for a course in marine biology or oceanology at the secondary level is presented. Among the topics discussed are: food webs and pyramids, planktonic blooms, marine life, plankton nets, food chains, phytoplankton, zooplankton, larval plankton and filter feeders. (BT)

  20. Scaffolded biology.

    Science.gov (United States)

    Minelli, Alessandro

    2016-09-01

    Descriptions and interpretations of the natural world are dominated by dichotomies such as organism vs. environment, nature vs. nurture, genetic vs. epigenetic, but in the last couple of decades strong dissatisfaction with those partitions has been repeatedly voiced and a number of alternative perspectives have been suggested, from perspectives such as Dawkins' extended phenotype, Turner's extended organism, Oyama's Developmental Systems Theory and Odling-Smee's niche construction theory. Last in time is the description of biological phenomena in terms of hybrids between an organism (scaffolded system) and a living or non-living scaffold, forming unit systems to study processes such as reproduction and development. As scaffold, eventually, we can define any resource used by the biological system, especially in development and reproduction, without incorporating it as happens in the case of resources fueling metabolism. Addressing biological systems as functionally scaffolded systems may help pointing to functional relationships that can impart temporal marking to the developmental process and thus explain its irreversibility; revisiting the boundary between development and metabolism and also regeneration phenomena, by suggesting a conceptual framework within which to investigate phenomena of regular hypermorphic regeneration such as characteristic of deer antlers; fixing a periodization of development in terms of the times at which a scaffolding relationship begins or is terminated; and promoting plant galls to legitimate study objects of developmental biology.

  1. Biology Notes.

    Science.gov (United States)

    School Science Review, 1984

    1984-01-01

    Presents information on the teaching of nutrition (including new information relating to many current O-level syllabi) and part 16 of a reading list for A- and S-level biology. Also includes a note on using earthworms as a source of material for teaching meiosis. (JN)

  2. Evolution and medicine.

    Science.gov (United States)

    Perlman, Robert L

    2013-01-01

    Evolutionary medicine is a new field whose goal is to incorporate an evolutionary perspective into medical education, research, and practice. Evolutionary biologists and physicians have traditionally been concerned with different problems and have developed different ways of approaching and understanding biological phenomena. Evolutionary biologists analyze the properties of populations and the ways in which populations change over time, while physicians focus on the care of their individual patients. Evolutionists are concerned with the ultimate causes of biological phenomena, causes that operated during the phylogenetic history of a species, while physicians and biomedical scientists have been more interested in proximate causes, causes that operate during the ontogeny and life of an individual. Evolutionary medicine is based on the belief that an integration of these complementary views of biological phenomena will improve our understanding of health and disease. This essay reviews the theory of evolution by natural selection, as it was developed by Darwin and as it is now understood by evolutionary biologists. It emphasizes the importance of variation and selection, points out the differences between evolutionary fitness and health, and discusses some of the reasons why our evolutionary heritage has left us vulnerable to disease.

  3. The meaning of biological information.

    Science.gov (United States)

    Koonin, Eugene V

    2016-03-13

    Biological information encoded in genomes is fundamentally different from and effectively orthogonal to Shannon entropy. The biologically relevant concept of information has to do with 'meaning', i.e. encoding various biological functions with various degree of evolutionary conservation. Apart from direct experimentation, the meaning, or biological information content, can be extracted and quantified from alignments of homologous nucleotide or amino acid sequences but generally not from a single sequence, using appropriately modified information theoretical formulae. For short, information encoded in genomes is defined vertically but not horizontally. Informally but substantially, biological information density seems to be equivalent to 'meaning' of genomic sequences that spans the entire range from sharply defined, universal meaning to effective meaninglessness. Large fractions of genomes, up to 90% in some plants, belong within the domain of fuzzy meaning. The sequences with fuzzy meaning can be recruited for various functions, with the meaning subsequently fixed, and also could perform generic functional roles that do not require sequence conservation. Biological meaning is continuously transferred between the genomes of selfish elements and hosts in the process of their coevolution. Thus, in order to adequately describe genome function and evolution, the concepts of information theory have to be adapted to incorporate the notion of meaning that is central to biology.

  4. Biology-Inspired Autonomous Control

    Science.gov (United States)

    2011-08-31

    of, and perhaps will not be tolerated in, manmade critical systems. Although this paper does not directly address questions of ethics associated...political, ethical , and moral issues associated with the use of autonomous systems in warfare will be debated long after the technology hurdles to...accessible discussion on the interplay of biochemistry, genetics and embryology in animal evolution; Wagner, 2005 describes biological concepts of

  5. Mesoscopic biology

    Indian Academy of Sciences (India)

    G V Shivashankar

    2002-02-01

    In this paper we present a qualitative outlook of mesoscopic biology where the typical length scale is of the order of nanometers and the energy scales comparable to thermal energy. Novel biomolecular machines, governed by coded information at the level of DNA and proteins, operate at these length scales in biological systems. In recent years advances in technology have led to the study of some of the design principles of these machines; in particular at the level of an individual molecule. For example, the forces that operate in molecular interactions, the stochasticity involved in these interactions and their spatio-temporal dynamics are beginning to be explored. Understanding such design principles is opening new possibilities in mesoscopic physics with potential applications.

  6. Monod and the spirit of molecular biology.

    Science.gov (United States)

    Morange, Michel

    2015-06-01

    The founders of molecular biology shared views on the place of biology within science, as well as on the relations of molecular biology to Darwinism. Jacques Monod was no exception, but the study of his writings is particularly interesting because he expressed his point of view very clearly and pushed the implications of some of his choices further than most of his contemporaries. The spirit of molecular biology is no longer the same as in the 1960s but, interestingly, Monod anticipated some recent evolutions of this discipline.

  7. Marine biology

    Energy Technology Data Exchange (ETDEWEB)

    Thurman, H.V.; Webber, H.H.

    1984-01-01

    This book discusses both taxonomic and ecological topics on marine biology. Full coverage of marine organisms of all five kingdoms is provided, along with interesting and thorough discussion of all major marine habitats. Organization into six major parts allows flexibility. It also provides insight into important topics such as disposal of nuclear waste at sea, the idea that life began on the ocean floor, and how whales, krill, and people interact. A full-color photo chapter reviews questions, and exercises. The contents are: an overview marine biology: fundamental concepts/investigating life in the ocean; the physical ocean, the ocean floor, the nature of water, the nature and motion of ocean water; general ecology, conditions for life in the sea, biological productivity and energy transfer; marine organisms; monera, protista, mycota and metaphyta; the smaller marine animals, the large animals marine habitats, the intertidal zone/benthos of the continental shelf, the photic zone, the deep ocean, the ocean under stress, marine pollution, appendix a: the metric system and conversion factors/ appendix b: prefixes and suffixes/ appendix c: taxonomic classification of common marine organisms, and glossary, and index.

  8. Extinction Events Can Accelerate Evolution

    DEFF Research Database (Denmark)

    Lehman, Joel; Miikkulainen, Risto

    2015-01-01

    computational support for this hypothesis, this paper shows how increased evolvability will result from simulated extinction events in two computational models of evolved behavior. The conclusion is that although they are destructive in the short term, extinction events may make evolution more prolific......Extinction events impact the trajectory of biological evolution significantly. They are often viewed as upheavals to the evolutionary process. In contrast, this paper supports the hypothesis that although they are unpredictably destructive, extinction events may in the long term accelerate...... evolution by increasing evolvability. In particular, if extinction events extinguish indiscriminately many ways of life, indirectly they may select for the ability to expand rapidly through vacated niches. Lineages with such an ability are more likely to persist through multiple extinctions. Lending...

  9. Extinction events can accelerate evolution.

    Directory of Open Access Journals (Sweden)

    Joel Lehman

    Full Text Available Extinction events impact the trajectory of biological evolution significantly. They are often viewed as upheavals to the evolutionary process. In contrast, this paper supports the hypothesis that although they are unpredictably destructive, extinction events may in the long term accelerate evolution by increasing evolvability. In particular, if extinction events extinguish indiscriminately many ways of life, indirectly they may select for the ability to expand rapidly through vacated niches. Lineages with such an ability are more likely to persist through multiple extinctions. Lending computational support for this hypothesis, this paper shows how increased evolvability will result from simulated extinction events in two computational models of evolved behavior. The conclusion is that although they are destructive in the short term, extinction events may make evolution more prolific in the long term.

  10. Extinction Events Can Accelerate Evolution

    Science.gov (United States)

    Lehman, Joel; Miikkulainen, Risto

    2015-01-01

    Extinction events impact the trajectory of biological evolution significantly. They are often viewed as upheavals to the evolutionary process. In contrast, this paper supports the hypothesis that although they are unpredictably destructive, extinction events may in the long term accelerate evolution by increasing evolvability. In particular, if extinction events extinguish indiscriminately many ways of life, indirectly they may select for the ability to expand rapidly through vacated niches. Lineages with such an ability are more likely to persist through multiple extinctions. Lending computational support for this hypothesis, this paper shows how increased evolvability will result from simulated extinction events in two computational models of evolved behavior. The conclusion is that although they are destructive in the short term, extinction events may make evolution more prolific in the long term. PMID:26266804

  11. Experimental evolution meets marine phytoplankton.

    Science.gov (United States)

    Reusch, Thorsten B H; Boyd, Philip W

    2013-07-01

    Our perspective highlights potentially important links between disparate fields-biological oceanography, climate change research, and experimental evolutionary biology. We focus on one important functional group-photoautotrophic microbes (phytoplankton), which are responsible for ∼50% of global primary productivity. Global climate change currently results in the simultaneous change of several conditions such as warming, acidification, and nutrient supply. It thus has the potential to dramatically change phytoplankton physiology, community composition, and may result in adaptive evolution. Although their large population sizes, standing genetic variation, and rapid turnover time should promote swift evolutionary change, oceanographers have focussed on describing patterns of present day physiological differentiation rather than measure potential adaptation in evolution experiments, the only direct way to address whether and at which rate phytoplankton species will adapt to environmental change. Important open questions are (1) is adaptation limited by existing genetic variation or fundamental constraints? (2) Will complex ecological settings such as gradual versus abrupt environmental change influence adaptation processes? (3) How will increasing environmental variability affect the evolution of phenotypic plasticity patterns? Because marine phytoplankton species display rapid acclimation capacity (phenotypic buffering), a systematic study of reaction norms renders them particularly interesting to the evolutionary biology research community.

  12. Adaptive evolution in ecological communities.

    Directory of Open Access Journals (Sweden)

    Martin M Turcotte

    Full Text Available Understanding how natural selection drives evolution is a key challenge in evolutionary biology. Most studies of adaptation focus on how a single environmental factor, such as increased temperature, affects evolution within a single species. The biological relevance of these experiments is limited because nature is infinitely more complex. Most species are embedded within communities containing many species that interact with one another and the physical environment. To understand the evolutionary significance of such ecological complexity, experiments must test the evolutionary impact of interactions among multiple species during adaptation. Here we highlight an experiment that manipulates species composition and tracks evolutionary responses within each species, while testing for the mechanisms by which species interact and adapt to their environment. We also discuss limitations of previous studies of adaptive evolution and emphasize how an experimental evolution approach can circumvent such shortcomings. Understanding how community composition acts as a selective force will improve our ability to predict how species adapt to natural and human-induced environmental change.

  13. Adaptive evolution in ecological communities.

    Science.gov (United States)

    Turcotte, Martin M; Corrin, Michael S C; Johnson, Marc T J

    2012-01-01

    Understanding how natural selection drives evolution is a key challenge in evolutionary biology. Most studies of adaptation focus on how a single environmental factor, such as increased temperature, affects evolution within a single species. The biological relevance of these experiments is limited because nature is infinitely more complex. Most species are embedded within communities containing many species that interact with one another and the physical environment. To understand the evolutionary significance of such ecological complexity, experiments must test the evolutionary impact of interactions among multiple species during adaptation. Here we highlight an experiment that manipulates species composition and tracks evolutionary responses within each species, while testing for the mechanisms by which species interact and adapt to their environment. We also discuss limitations of previous studies of adaptive evolution and emphasize how an experimental evolution approach can circumvent such shortcomings. Understanding how community composition acts as a selective force will improve our ability to predict how species adapt to natural and human-induced environmental change.

  14. Language architecture and its import for evolution.

    Science.gov (United States)

    Chomsky, Noam

    2017-02-07

    Inquiry into the evolution of some biological system evidently can proceed only as far as its nature is understood. Lacking such understanding, its manifestations are likely to appear to be chaotic, highly variable, and lacking significant general properties; and, accordingly, study of its evolution cannot be seriously undertaken. These truisms hold of the study of the human faculty of language FL just as for other biological systems. As discussed below, FL appears to be a shared human capacity in essentials, with options of variation of a kind to which we return. After a long lapse, the problem of evolution of language arose in mid-twentieth century when the first efforts were made to construct accounts of FL as a biological object, internal to an individual, with particular internal languages - I-languages in current terminology - as manifestations of FL.

  15. CHEMICAL EVOLUTION

    Energy Technology Data Exchange (ETDEWEB)

    Calvin, Melvin

    1965-06-01

    How did life come to be on the surface of the earth? Darwin himself recognized that his basic idea of evolution by variation and natural selection must be a continuous process extending backward in time through that period in which the first living things arose and into the period of 'Chemical Evolution' which preceded it. We are approaching the examination of these events by two routes. One is to seek for evidence in the ancient rocks of the earth which were laid down prior to that time in which organisms capable of leaving their skeletons in the rocks to be fossilized were in existence. This period is sometime prior to approximately 600 million years ago. The earth is believed to have taken its present form approximately 4700 million years ago. We have found in rocks whose age is about 1000 million years certain organic molecules which are closely related to the green pigment of plants, chlorophyll. This seems to establish that green plants were already fluorishing prior to that time. We have now found in rocks of still greater age, namely, 2500 million years, the same kinds of molecules mentioned above which can be attributed to the presence of living organisms. If these molecules are as old as the rocks, we have thus shortened the time available for the generation of the complex biosynthetic sequences which give rise to these specific hydrocarbons (polyisoprenoids) to less than 2000 million years.

  16. Molecular biology of potyviruses.

    Science.gov (United States)

    Revers, Frédéric; García, Juan Antonio

    2015-01-01

    Potyvirus is the largest genus of plant viruses causing significant losses in a wide range of crops. Potyviruses are aphid transmitted in a nonpersistent manner and some of them are also seed transmitted. As important pathogens, potyviruses are much more studied than other plant viruses belonging to other genera and their study covers many aspects of plant virology, such as functional characterization of viral proteins, molecular interaction with hosts and vectors, structure, taxonomy, evolution, epidemiology, and diagnosis. Biotechnological applications of potyviruses are also being explored. During this last decade, substantial advances have been made in the understanding of the molecular biology of these viruses and the functions of their various proteins. After a general presentation on the family Potyviridae and the potyviral proteins, we present an update of the knowledge on potyvirus multiplication, movement, and transmission and on potyvirus/plant compatible interactions including pathogenicity and symptom determinants. We end the review providing information on biotechnological applications of potyviruses.

  17. Networks in Cell Biology

    Science.gov (United States)

    Buchanan, Mark; Caldarelli, Guido; De Los Rios, Paolo; Rao, Francesco; Vendruscolo, Michele

    2010-05-01

    Introduction; 1. Network views of the cell Paolo De Los Rios and Michele Vendruscolo; 2. Transcriptional regulatory networks Sarath Chandra Janga and M. Madan Babu; 3. Transcription factors and gene regulatory networks Matteo Brilli, Elissa Calistri and Pietro Lió; 4. Experimental methods for protein interaction identification Peter Uetz, Björn Titz, Seesandra V. Rajagopala and Gerard Cagney; 5. Modeling protein interaction networks Francesco Rao; 6. Dynamics and evolution of metabolic networks Daniel Segré; 7. Hierarchical modularity in biological networks: the case of metabolic networks Erzsébet Ravasz Regan; 8. Signalling networks Gian Paolo Rossini; Appendix 1. Complex networks: from local to global properties D. Garlaschelli and G. Caldarelli; Appendix 2. Modelling the local structure of networks D. Garlaschelli and G. Caldarelli; Appendix 3. Higher-order topological properties S. Ahnert, T. Fink and G. Caldarelli; Appendix 4. Elementary mathematical concepts A. Gabrielli and G. Caldarelli; References.

  18. Viral quasispecies evolution.

    Science.gov (United States)

    Domingo, Esteban; Sheldon, Julie; Perales, Celia

    2012-06-01

    Evolution of RNA viruses occurs through disequilibria of collections of closely related mutant spectra or mutant clouds termed viral quasispecies. Here we review the origin of the quasispecies concept and some biological implications of quasispecies dynamics. Two main aspects are addressed: (i) mutant clouds as reservoirs of phenotypic variants for virus adaptability and (ii) the internal interactions that are established within mutant spectra that render a virus ensemble the unit of selection. The understanding of viruses as quasispecies has led to new antiviral designs, such as lethal mutagenesis, whose aim is to drive viruses toward low fitness values with limited chances of fitness recovery. The impact of quasispecies for three salient human pathogens, human immunodeficiency virus and the hepatitis B and C viruses, is reviewed, with emphasis on antiviral treatment strategies. Finally, extensions of quasispecies to nonviral systems are briefly mentioned to emphasize the broad applicability of quasispecies theory.

  19. Communicating Change The Promise of Human Evolution

    OpenAIRE

    James Lull; Eduardo Neiva

    2008-01-01

    In the present age, human evolution no longer follows the same principal of biological evolution, resulting from the adaptation and survival of competitive species in nature in terms of random mutations. This transformation varies in terms of cultural innovations and moral determinations, the hallmark human species, the only one to subordinate their interests to other genetic issues deems most relevant. The pace of change has accelerated remarkably in the last millennium, especially after the...

  20. Biological Databases

    Directory of Open Access Journals (Sweden)

    Kaviena Baskaran

    2013-12-01

    Full Text Available Biology has entered a new era in distributing information based on database and this collection of database become primary in publishing information. This data publishing is done through Internet Gopher where information resources easy and affordable offered by powerful research tools. The more important thing now is the development of high quality and professionally operated electronic data publishing sites. To enhance the service and appropriate editorial and policies for electronic data publishing has been established and editors of article shoulder the responsibility.

  1. LA (R EVOLUCIÓN INFORMÁTICA EN BIOLOGÍA:: EL CASO DE LA GENÓMICA The Informatics (R Evolution in Biology:: The Case of Genomics

    Directory of Open Access Journals (Sweden)

    LAYLA MICHÁN AGUIRRE

    Full Text Available La biología ha evolucionado rápidamente en las últimas décadas; uno de los indicadores de este fenómeno ha sido la introducción de nuevas disciplinas, tal es el caso de la genómica que se originó en la década de los años 80 y ha dado un giro inverosímil a la ciencia moderna, dicha disciplina hace referencia al estudio no solo de los genes, sino de sus funciones, relaciones entre sí y con el medio ambiente. Surgió con la consolidación del proyecto genoma humano en un periodo de transición donde el conocimiento genético específico se tornó crítico. Se diferencia de otros enfoques (por ejemplo: la ecología, la biología evolutiva en el tipo de información que ofrece, las perspectivas de mejoras técnicas e intelectuales en la obtención y explotación de datos de todo el ge-noma (Murray, 2000. Presentamos un breve análisis bibliométrico en el que se muestra el desarrollo y las principales tendencias de esta disciplina biológica en boga.Biology has been revolutionized by the introduction of new disciplines, such is the case of genomics that introduced in the 80s has turned unlikely to modern science, the discipline refers to the study not only of genes but their roles, relations among themselves and with the environment. Arises, with the consolidation of the Human Genome Project and introduces us to a period of transition in which specific genetic knowledge becomes critical. Differs from other approaches in the type of information provided, the prospects for technical and intellectual improvements in the collection and use of data from the whole genome. A brief bibliometric analysis which shows the development and the main trends of this biological discipline in vogue.

  2. Human evolution

    DEFF Research Database (Denmark)

    Llamas, Bastien; Willerslev, Eske; Orlando, Ludovic

    2017-01-01

    , and true population genomic studies of Bronze Age populations. Among the emerging areas of aDNA research, the analysis of past epigenomes is set to provide more new insights into human adaptation and disease susceptibility through time. Starting as a mere curiosity, ancient human genetics has become......The field of human ancient DNA (aDNA) has moved from mitochondrial sequencing that suffered from contamination and provided limited biological insights, to become a fully genomic discipline that is changing our conception of human history. Recent successes include the sequencing of extinct hominins...

  3. Networks of lexical borrowing and lateral gene transfer in language and genome evolution.

    Science.gov (United States)

    List, Johann-Mattis; Nelson-Sathi, Shijulal; Geisler, Hans; Martin, William

    2014-02-01

    Like biological species, languages change over time. As noted by Darwin, there are many parallels between language evolution and biological evolution. Insights into these parallels have also undergone change in the past 150 years. Just like genes, words change over time, and language evolution can be likened to genome evolution accordingly, but what kind of evolution? There are fundamental differences between eukaryotic and prokaryotic evolution. In the former, natural variation entails the gradual accumulation of minor mutations in alleles. In the latter, lateral gene transfer is an integral mechanism of natural variation. The study of language evolution using biological methods has attracted much interest of late, most approaches focusing on language tree construction. These approaches may underestimate the important role that borrowing plays in language evolution. Network approaches that were originally designed to study lateral gene transfer may provide more realistic insights into the complexities of language evolution.

  4. New Frontiers in Language Evolution and Development.

    Science.gov (United States)

    Oller, D Kimbrough; Dale, Rick; Griebel, Ulrike

    2016-04-01

    This article introduces the Special Issue and its focus on research in language evolution with emphasis on theory as well as computational and robotic modeling. A key theme is based on the growth of evolutionary developmental biology or evo-devo. The Special Issue consists of 13 articles organized in two sections: A) Theoretical foundations and B) Modeling and simulation studies. All the papers are interdisciplinary in nature, encompassing work in biological and linguistic foundations for the study of language evolution as well as a variety of computational and robotic modeling efforts shedding light on how language may be developed and may have evolved.

  5. Thought Evolution

    Directory of Open Access Journals (Sweden)

    Shadrikov V.D.

    2015-08-01

    Full Text Available The thought evolution is studied by historical reconstruction method that is based on the propositions of the theory of culturalhistorical determination of the psyche development, and the data of the morphological analysis and child development, and the conception of the psyche neuroontogenesis. The grounds for advisability of protothinking are presented. The protothinking is understood as the use of objective thought in cases of awareness absence. It is shown that protothinking is a form of transition from animal thinking to human speech. The particular attention is paid to the process of the word producing and thought generation in that process. The conditions of word producing as cooccurring acoustic pattern served for though expression are discussed. It is emphasized that a word is produced by a particular person. The historical development of the language and the specificity of this development are pointed out

  6. Community Evolution

    CERN Document Server

    Bródka, Piotr; Kazienko, Przemysław

    2016-01-01

    The continuous interest in the social network area contributes to the fast development of this field. The new possibilities of obtaining and storing data facilitate deeper analysis of the entire social network, extracted social groups and single individuals as well. One of the most interesting research topic is the network dynamics and dynamics of social groups in particular, it means analysis of group evolution over time. It is the natural step forward after social community extraction. Having communities extracted, appropriate knowledge and methods for dynamic analysis may be applied in order to identify changes as well as to predict the future of all or some selected groups. Furthermore, knowing the most probably change of a given group some additional steps may be performed in order to change this predicted future according to specific needs. Such ability would be a powerful tool in the hands of human resource managers, personnel recruitment, marketing, telecommunication companies, etc.

  7. Biological biomaterials

    Energy Technology Data Exchange (ETDEWEB)

    Jorge-Herrero, E. [Servicio de Cirugia Experimental. Clinica Puerta de Hierro, Madrid (Spain)

    1997-05-01

    There are a number of situations in which substances of biological origin are employed as biomaterials. Most of them are macromolecules derived from isolated connective tissue or the connective tissue itself in membrane form, in both cases, the tissue can be used in its natural form or be chemically treated. In other cases, certain blood vessels can be chemically pretreated and used as vascular prostheses. Proteins such as albumin, collagen and fibrinogen are employed to coat vascular prostheses. Certain polysaccharides have also been tested for use in controlled drug release systems. Likewise, a number of tissues, such as dura mater, bovine pericardium, procine valves and human valves, are used in the preparation of cardiac prostheses. We also use veins from animals or humans in arterial replacement. In none of these cases are the tissues employed dissimilar to the native tissues as they have been chemically modified, becoming a new bio material with different physical and biochemical properties. In short, we find that natural products are being utilized as biomaterials and must be considered as such; thus, it is necessary to study both their chemicobiological and physicomechanical properties. In the present report, we review the current applications, problems and future prospects of some of these biological biomaterials. (Author) 84 refs.

  8. Ultrastructure, macromolecules, and evolution

    CERN Document Server

    Dillon, Lawrence S

    1981-01-01

    Thus far in the history of biology, two, and only two, fundamental principles have come to light that pervade and unify the entire science-the cell theory and the concept of evolution. While it is true that recently opened fields of inves­ tigation have given rise to several generalizations of wide impact, such as the universality of DNA and the energetic dynamics of ecology, closer inspection reveals them to be part and parcel of either of the first two mentioned. Because in the final analysis energy can act upon an organism solely at the cellular level, its effects may be perceived basically to represent one facet of cell me­ tabolism. Similarly, because the DNA theory centers upon the means by which cells build proteins and reproduce themselves, it too proves to be only one more, even though an exciting, aspect of the cell theory. In fact, if the matter is given closer scrutiny, evolution itself can be viewed as being a fundamental portion of the cell concept, for its effects arise only as a consequence ...

  9. Evolution of dietary antioxidants.

    Science.gov (United States)

    Benzie, Iris F F

    2003-09-01

    Oxygen is vital for most organisms but, paradoxically, damages key biological sites. Oxygenic threat is met by antioxidants that evolved in parallel with our oxygenic atmosphere. Plants employ antioxidants to defend their structures against reactive oxygen species (ROS; oxidants) produced during photosynthesis. The human body is exposed to these same oxidants, and we have also evolved an effective antioxidant system. However, this is not infallible. ROS breach defences, oxidative damage ensues, accumulates with age, and causes a variety of pathological changes. Plant-based, antioxidant-rich foods traditionally formed the major part of the human diet, and plant-based dietary antioxidants are hypothesized to have an important role in maintaining human health. This hypothesis is logical in evolutionary terms, especially when we consider the relatively hypoxic environment in which humans may have evolved. In this paper, the human diet is discussed briefly in terms of its evolutionary development, different strategies of antioxidant defence are outlined, and evolution of dietary antioxidants is discussed from the perspectives of plant need and our current dietary requirements. Finally, possibilities in regard to dietary antioxidants, evolution, and human health are presented, and an evolutionary cost-benefit analysis is presented in relation to why we lost the ability to make ascorbic acid (vitamin C) although we retained an absolute requirement for it.

  10. Cyanobacterial evolution during the Precambrian

    Science.gov (United States)

    Schirrmeister, Bettina E.; Sanchez-Baracaldo, Patricia; Wacey, David

    2016-07-01

    Life on Earth has existed for at least 3.5 billion years. Yet, relatively little is known of its evolution during the first two billion years, due to the scarceness and generally poor preservation of fossilized biological material. Cyanobacteria, formerly known as blue green algae were among the first crown Eubacteria to evolve and for more than 2.5 billion years they have strongly influenced Earth's biosphere. Being the only organism where oxygenic photosynthesis has originated, they have oxygenated Earth's atmosphere and hydrosphere, triggered the evolution of plants -being ancestral to chloroplasts- and enabled the evolution of complex life based on aerobic respiration. Having such a strong impact on early life, one might expect that the evolutionary success of this group may also have triggered further biosphere changes during early Earth history. However, very little is known about the early evolution of this phylum and ongoing debates about cyanobacterial fossils, biomarkers and molecular clock analyses highlight the difficulties in this field of research. Although phylogenomic analyses have provided promising glimpses into the early evolution of cyanobacteria, estimated divergence ages are often very uncertain, because of vague and insufficient tree-calibrations. Results of molecular clock analyses are intrinsically tied to these prior calibration points, hence improving calibrations will enable more precise divergence time estimations. Here we provide a review of previously described Precambrian microfossils, biomarkers and geochemical markers that inform upon the early evolution of cyanobacteria. Future research in micropalaeontology will require novel analyses and imaging techniques to improve taxonomic affiliation of many Precambrian microfossils. Consequently, a better understanding of early cyanobacterial evolution will not only allow for a more specific calibration of cyanobacterial and eubacterial phylogenies, but also provide new dates for the tree

  11. Iterated learning and the evolution of language.

    Science.gov (United States)

    Kirby, Simon; Griffiths, Tom; Smith, Kenny

    2014-10-01

    Iterated learning describes the process whereby an individual learns their behaviour by exposure to another individual's behaviour, who themselves learnt it in the same way. It can be seen as a key mechanism of cultural evolution. We review various methods for understanding how behaviour is shaped by the iterated learning process: computational agent-based simulations; mathematical modelling; and laboratory experiments in humans and non-human animals. We show how this framework has been used to explain the origins of structure in language, and argue that cultural evolution must be considered alongside biological evolution in explanations of language origins.

  12. Darwin and the popularization of evolution.

    Science.gov (United States)

    Lightman, Bernard

    2010-03-20

    Evolution was popularized from 1860 to 1900 in the USA and Britain in a wide variety of media. Here I investigate traditional texts associated with the intellectual elite, including philosophical or scientific monographs, sermons, and published lectures. Evolution was rarely popularized in ways that reflected Darwin's major contribution to biology, his theory of natural selection. This meant that the reading audience more often encountered an alternative to Darwin's naturalistic, non-directional and non-progressive evolutionary perspective. There were at least four different versions of evolution circulating in the period from 1860 to 1900, and only one conformed to Darwin's vision.

  13. Evolution and the second law of thermodynamics

    CERN Document Server

    Bunn, Emory F

    2009-01-01

    Skeptics of biological evolution often claim that evolution requires a decrease in entropy, giving rise to a conflict with the second law of thermodynamics. This argument is fallacious because it neglects the large increase in entropy provided by sunlight striking the Earth. A recent article provided a quantitative assessment of the entropies involved and showed explicitly that there is no conflict. That article rests on an unjustified assumption about the amount of entropy reduction involved in evolution. I present a refinement of the argument that does not rely on this assumption.

  14. Synthetic biology in plastids.

    Science.gov (United States)

    Scharff, Lars B; Bock, Ralph

    2014-06-01

    Plastids (chloroplasts) harbor a small gene-dense genome that is amenable to genetic manipulation by transformation. During 1 billion years of evolution from the cyanobacterial endosymbiont to present-day chloroplasts, the plastid genome has undergone a dramatic size reduction, mainly as a result of gene losses and the large-scale transfer of genes to the nuclear genome. Thus the plastid genome can be regarded as a naturally evolved miniature genome, the gradual size reduction and compaction of which has provided a blueprint for the design of minimum genomes. Furthermore, because of the largely prokaryotic genome structure and gene expression machinery, the high transgene expression levels attainable in transgenic chloroplasts and the very low production costs in plant systems, the chloroplast lends itself to synthetic biology applications that are directed towards the efficient synthesis of green chemicals, biopharmaceuticals and other metabolites of commercial interest. This review describes recent progress with the engineering of plastid genomes with large constructs of foreign or synthetic DNA, and highlights the potential of the chloroplast as a model system in bottom-up and top-down synthetic biology approaches.

  15. Experimental evolution in fungi: An untapped resource.

    Science.gov (United States)

    Fisher, Kaitlin J; Lang, Gregory I

    2016-09-01

    Historically, evolutionary biology has been considered an observational science. Examining populations and inferring evolutionary histories mold evolutionary theories. In contrast, laboratory evolution experiments make use of the amenability of traditional model organisms to study fundamental processes underlying evolution in real time in simple, but well-controlled, environments. With advances in high-throughput biology and next generation sequencing, it is now possible to propagate hundreds of parallel populations over thousands of generations and to quantify precisely the frequencies of various mutations over time. Experimental evolution combines the ability to simultaneously monitor replicate populations with the power to vary individual parameters to test specific evolutionary hypotheses, something that is impractical or infeasible in natural populations. Many labs are now conducting laboratory evolution experiments in nearly all model systems including viruses, bacteria, yeast, nematodes, and fruit flies. Among these systems, fungi occupy a unique niche: with a short generation time, small compact genomes, and sexual cycles, fungi are a particularly valuable and largely untapped resource for propelling future growth in the field of experimental evolution. Here, we describe the current state of fungal experimental evolution and why fungi are uniquely positioned to answer many of the outstanding questions in the field. We also review which fungal species are most well suited for experimental evolution.

  16. Motilin and ghrelin gene experienced episodic evolution during primitive placental mammal evolution

    Institute of Scientific and Technical Information of China (English)

    IRWIN; M.; David

    2010-01-01

    Motilin and ghrelin,members of a structure-function-related hormone family,play important roles in gastrointestinal function,regulation of energy homeostasis and growth hormone secretion.We observed episodic evolution in both of their prehormone gene sequences during primitive placental mammal evolution,during which most of the nonsynonymous changes result in radical substitution.Of note,a functional obestatin hormone might have only originated after this episodic evolution event.Early in placental mammal evolution,a series of biology complexities evolved.At the same time the motilin and ghrelin prehormone genes,which play important roles in several of these processes,experienced episodic evolution with dramatic changes in their coding sequences.These observations suggest that some of the lineage-specific physiological adaptations are due to episodic evolution of the motilin and ghrelin genes.

  17. Synergistic Synthetic Biology: Units in Concert.

    Science.gov (United States)

    Trosset, Jean-Yves; Carbonell, Pablo

    2013-01-01

    Synthetic biology aims at translating the methods and strategies from engineering into biology in order to streamline the design and construction of biological devices through standardized parts. Modular synthetic biology devices are designed by means of an adequate elimination of cross-talk that makes circuits orthogonal and specific. To that end, synthetic constructs need to be adequately optimized through in silico modeling by choosing the right complement of genetic parts and by experimental tuning through directed evolution and craftsmanship. In this review, we consider an additional and complementary tool available to the synthetic biologist for innovative design and successful construction of desired circuit functionalities: biological synergies. Synergy is a prevalent emergent property in biological systems that arises from the concerted action of multiple factors producing an amplification or cancelation effect compared with individual actions alone. Synergies appear in domains as diverse as those involved in chemical and protein activity, polypharmacology, and metabolic pathway complementarity. In conventional synthetic biology designs, synergistic cross-talk between parts and modules is generally attenuated in order to verify their orthogonality. Synergistic interactions, however, can induce emergent behavior that might prove useful for synthetic biology applications, like in functional circuit design, multi-drug treatment, or in sensing and delivery devices. Synergistic design principles are therefore complementary to those coming from orthogonal design and may provide added value to synthetic biology applications. The appropriate modeling, characterization, and design of synergies between biological parts and units will allow the discovery of yet unforeseeable, novel synthetic biology applications.

  18. Professor Attitudes and Beliefs about Teaching Evolution

    Science.gov (United States)

    Barnes, Maryann Elizabeth

    Teaching evolution has been shown to be a challenge for faculty, in both K-12 and postsecondary education. Many of these challenges stem from perceived conflicts not only between religion and evolution, but also faculty beliefs about religion, it's compatibility with evolutionary theory, and it's proper role in classroom curriculum. Studies suggest that if educators engage with students' religious beliefs and identity, this may help students have positive attitudes towards evolution. The aim of this study was to reveal attitudes and beliefs professors have about addressing religion and providing religious scientist role models to students when teaching evolution. 15 semi-structured interviews of tenured biology professors were conducted at a large Midwestern universiy regarding their beliefs, experiences, and strategies teaching evolution and particularly, their willingness to address religion in a class section on evolution. Following a qualitative analysis of transcripts, professors did not agree on whether or not it is their job to help students accept evolution (although the majority said it is not), nor did they agree on a definition of "acceptance of evolution". Professors are willing to engage in students' religious beliefs, if this would help their students accept evolution. Finally, professors perceived many challenges to engaging students' religious beliefs in a science classroom such as the appropriateness of the material for a science class, large class sizes, and time constraints. Given the results of this study, the author concludes that instructors must come to a consensus about their goals as biology educators as well as what "acceptance of evolution" means, before they can realistically apply the engagement of student's religious beliefs and identity as an educational strategy.

  19. Groupware requirements evolution patterns

    NARCIS (Netherlands)

    Pumareja, Dulce Trinidad

    2013-01-01

    Requirements evolution is a generally known problem in software development. Requirements are known to change all throughout a system's lifecycle. Nevertheless, requirements evolution is a poorly understood phenomenon. Most studies on requirements evolution focus on changes to written specifications

  20. Evolution of specialization and ecological character displacement: metabolic plasticity matters.

    NARCIS (Netherlands)

    Egas, C.J.M.; Reydon, Th.A.C.; Hemerik, L.

    2005-01-01

    An important question in evolutionary biology, especially with respect to herbivorous arthropods, is the evolution of specialization. In a previous paper, the combined evolutionary dynamics of specialization and ecological character displacement was studied, focusing on the role of herbivore foragin

  1. The balanced minimum evolution problem under uncertain data

    NARCIS (Netherlands)

    Catanzaro, Daniele; Labbe, Martine; Pesenti, Raffaele

    2013-01-01

    We investigate the Robust Deviation Balanced Minimum Evolution Problem (RDBMEP), a combinatorial optimization problem that arises in computational biology when the evolutionary distances from taxa are uncertain and varying inside intervals. By exploiting some fundamental properties of the objective

  2. Structural Biology Fact Sheet

    Science.gov (United States)

    ... Home > Science Education > Structural Biology Fact Sheet Structural Biology Fact Sheet Tagline (Optional) Middle/Main Content Area What is structural biology? Structural biology is a field of science focused ...

  3. Simulating Biological and Non-Biological Motion

    Science.gov (United States)

    Bruzzo, Angela; Gesierich, Benno; Wohlschlager, Andreas

    2008-01-01

    It is widely accepted that the brain processes biological and non-biological movements in distinct neural circuits. Biological motion, in contrast to non-biological motion, refers to active movements of living beings. Aim of our experiment was to investigate the mechanisms underlying mental simulation of these two movement types. Subjects had to…

  4. A Brief Introduction to Chinese Biological Biological

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Chinese Biological Abstracts sponsored by the Library, the Shanghai Institutes for Biological Sciences, the Biological Documentation and Information Network, all of the Chinese Academy of Sciences, commenced publication in 1987 and was initiated to provide access to the Chinese information in the field of biology.

  5. Astrobiology and the Biological Universe

    Science.gov (United States)

    Dick, S. J.

    2002-12-01

    Four hundred years ago two astronomical world views hung in the balance: the geocentric and the heliocentric. Today astronomy faces a similar choice between two grand world views: a purely physical universe, in which cosmic evolution commonly ends in planets, stars and galaxies, and a biological universe, in which cosmic evolution routinely results in life, mind and intelligence. Astrobiology is the science providing the data to make this critical choice. This 20th century overview shows how we have arrived at the view that cosmic evolution may have resulted in life and intelligence in the universe. It examines how our astronomical world view has changed over the last century, recalls the opinions of astronomical pioneers like Russell, Shapley, and Struve on life in the universe, and shows how planetary science, planetary systems science, origins of life studies and SETI have combined to form a new discipline. Astrobiology now commands \\$50 million in direct funding from NASA, funds 15 Astrobiology Institute members around the country and four affiliates around the world, and seeks to answer one of astronomy's oldest questions. Whether we live in a mostly physical universe, as exemplified in Isaac Asimov's Foundation series, or in a biological universe, as portrayed in Arthur C. Clarke's works, this reality will have profound consequences, no less than the Copernican theory. Astrobiology also looks to the future of life; taking a long-term ``Stapledonian" view, it is possible we may live in a postbiological universe.

  6. On the thermodynamics of multilevel evolution.

    Science.gov (United States)

    Tessera, Marc; Hoelzer, Guy A

    2013-09-01

    Biodiversity is hierarchically structured both phylogenetically and functionally. Phylogenetic hierarchy is understood as a product of branching organic evolution as described by Darwin. Ecosystem biologists understand some aspects of functional hierarchy, such as food web architecture, as a product of evolutionary ecology; but functional hierarchy extends to much lower scales of organization than those studied by ecologists. We argue that the more general use of the term "evolution" employed by physicists and applied to non-living systems connects directly to the narrow biological meaning. Physical evolution is best understood as a thermodynamic phenomenon, and this perspective comfortably includes all of biological evolution. We suggest four dynamical factors that build on each other in a hierarchical fashion and set the stage for the Darwinian evolution of biological systems: (1) the entropic erosion of structure; (2) the construction of dissipative systems; (3) the reproduction of growing systems and (4) the historical memory accrued to populations of reproductive agents by the acquisition of hereditary mechanisms. A particular level of evolution can underpin the emergence of higher levels, but evolutionary processes persist at each level in the hierarchy. We also argue that particular evolutionary processes can occur at any level of the hierarchy where they are not obstructed by material constraints. This theoretical framework provides an extensive basis for understanding natural selection as a multilevel process. The extensive literature on thermodynamics in turn provides an important advantage to this perspective on the evolution of higher levels of organization, such as the evolution of altruism that can accompany the emergence of social organization.

  7. Theoretical aspects of Systems Biology.

    Science.gov (United States)

    Bizzarri, Mariano; Palombo, Alessandro; Cucina, Alessandra

    2013-05-01

    The natural world consists of hierarchical levels of complexity that range from subatomic particles and molecules to ecosystems and beyond. This implies that, in order to explain the features and behavior of a whole system, a theory might be required that would operate at the corresponding hierarchical level, i.e. where self-organization processes take place. In the past, biological research has focused on questions that could be answered by a reductionist program of genetics. The organism (and its development) was considered an epiphenomenona of its genes. However, a profound rethinking of the biological paradigm is now underway and it is likely that such a process will lead to a conceptual revolution emerging from the ashes of reductionism. This revolution implies the search for general principles on which a cogent theory of biology might rely. Because much of the logic of living systems is located at higher levels, it is imperative to focus on them. Indeed, both evolution and physiology work on these levels. Thus, by no means Systems Biology could be considered a 'simple' 'gradual' extension of Molecular Biology.

  8. Nudging Evolution?

    Directory of Open Access Journals (Sweden)

    Katharine N. Farrell

    2013-12-01

    Full Text Available This Special Feature, "Nudging Evolution? Critical Exploration of the Potential and Limitations of the Concept of Institutional Fit for the Study and Adaptive Management of Social-Ecological Systems," aims to contribute toward the development of social theory and social research methods for the study of social-ecological system dynamics. Our objective is to help strengthen the academic discourse concerning if, and if so, how, to what extent, and in what concrete ways the concept of institutional "fit" might play a role in helping to develop better understanding of the social components of interlinkages between the socioeconomic-cultural and ecological dynamics of social-ecological systems. Two clearly discernible patterns provide a map of this Special Feature: (1 One pattern is the authors' positions regarding the place and role of normativity within their studies and assessment of institutional fit. Some place this at the center of their studies, exploring phenomena endogenous to the process of defining what constitutes institutional fit, whereas others take the formation of norms as a phenomenon exogenous to their study. (2 Another pattern is the type of studies presented: critiques and elaborations of the theory, methods for judging qualities of fit, and/or applied case studies using the concept. As a body of work, these contributions highlight that self-understanding of social-ecological place, whether explicit or implicit, constitutes an important part of the study object, i.e., the role of institutions in social-ecological systems, and that this is, at the same time, a crucial point of reference for the scholar wishing to evaluate what constitutes institutional fit and how it might be brought into being.

  9. College biology students' conceptions related to the nature of biological knowledge: Implications for conceptual change

    Science.gov (United States)

    Ameny, Gloria Millie Apio

    Adequate understanding of the nature of science is a major goal of science education. Understanding of the evolutionary nature of biological knowledge is a means of reinforcing biology students' understanding of the nature of science. It provides students with the philosophical basis, explanatory ideals, and subject matter-specific views of what counts as a scientifically-acceptable biological explanation. This study examined 121 college introductory biology and advanced zoology students for their conceptions related to the nature of biological knowledge. A 60-item Likert-scale questionnaire called the Nature of Biological Knowledge Scale and student interviews were used as complementary research instruments. Firstly, the study showed that 80--100% of college biology students have an adequate understanding of scientific methods, and that a similar percentage of students had learned the theory of evolution by natural selection in their biology courses. Secondly, the study showed that at least 60--80% of the students do not understand the importance of evolution in biological knowledge. Yet the study revealed that a statistically significant positive correlation exist among students' understanding of natural selection, divergent, and convergent evolutionary models. Thirdly, the study showed that about 20--58% of college students hold prescientific conceptions which, in part, are responsible for students' lack of understanding of the nature of biological knowledge. A statistically significant negative correlation was found among students' prescientific conceptions about basis of biological knowledge and nature of change in biological processes, and their understanding of natural selection and evolutionary models. However, the study showed that students' characteristics such as gender, age, major, or years in college have no statistically significant influence on students' conceptions related to the nature of biological knowledge. Only students' depth of biological

  10. Methods in molecular biology: plant cytogenetics

    Science.gov (United States)

    Cytogenetic studies have contributed greatly to our understanding of genetics, biology, reproduction, and evolution. From early studies in basic chromosome behavior the field has expanded enabling whole genome analysis to the manipulation of chromosomes and their organization. This book covers a ran...

  11. Teaching Evolution: From SMART Objectives to Threshold Experience

    Science.gov (United States)

    Wolf, Alexander; Akkaraju, Shylaja

    2014-01-01

    Despite the centrality of evolution to the study of biology, the pedagogical methods employed to teach the subject are often instructor-centered and rarely embedded in every topic throughout the curriculum. In addition, students' prior beliefs about evolution are often dismissed rather than incorporated into the classroom. In this article we…

  12. Teaching Evolution: A Heuristic Study of Personal and Cultural Dissonance

    Science.gov (United States)

    Grimes, Larry G.

    2012-01-01

    Darwinian evolution is a robustly supported scientific theory. Yet creationists continue to challenge its teaching in American public schools. Biology teachers in all 50 states are responsible for teaching science content standards that include evolution. As products of their backgrounds and affiliations teachers bring personal attitudes and…

  13. Qualitative Differences between Naive and Scientific Theories of Evolution

    Science.gov (United States)

    Shtulman, Andrew

    2006-01-01

    Philosophers of biology have long argued that Darwin's theory of evolution was qualitatively different from all earlier theories of evolution. Whereas Darwin's predecessors and contemporaries explained adaptation as the transformation of a species' ''essence,'' Darwin explained adaptation as the selective propagation of randomly occurring…

  14. Getting to Darwin: Obstacles to Accepting Evolution by Natural Selection

    Science.gov (United States)

    Thagard, Paul; Findlay, Scott

    2010-01-01

    Darwin's theory of evolution by natural selection is central to modern biology, but is resisted by many people. This paper discusses the major psychological obstacles to accepting Darwin's theory. Cognitive obstacles to adopting evolution by natural selection include conceptual difficulties, methodological issues, and coherence problems that…

  15. The Evolution of the Language Faculty: Clarifications and Implications

    Science.gov (United States)

    Fitch, W. Tecumseh; Hauser, Marc D.; Chomsky, Noam

    2005-01-01

    In this response to Pinker and Jackendoff's critique, we extend our previous framework for discussion of language evolution, clarifying certain distinctions and elaborating on a number of points. In the first half of the paper, we reiterate that profitable research into the biology and evolution of language requires fractionation of ''language''…

  16. The evolution of innate lymphoid cells

    Science.gov (United States)

    Vivier, Eric; van de Pavert, Serge A; Cooper, Max D; Belz, Gabrielle T

    2017-01-01

    Innate lymphoid cells (ILCs) are the most recently discovered group of immune cells. Understanding their biology poses many challenges. We discuss here the current knowledge on the appearance of ILC subsets during evolution and propose how the connection between ILCs and T cells contributes to the robustness of immunity and hence to the fitness of the hosts. PMID:27328009

  17. The Theory of Evolution: An Educational Perspective.

    Science.gov (United States)

    Johnson, William L.; Johnson, Annabel M.

    The article's thesis is that evolution's intellectual foundations have been steadily eroding, and that few new findings in embryology, taxonomy, fossil remains, and molecular biology are bringing us very near to a formal, logical disproof of Darwinian claims. The paper begins by discussing the evidence of a prehistoric world, then they discuss…

  18. Molecular evolution of mammalian ribonucleases 1

    NARCIS (Netherlands)

    Dubois, J.Y; Ursing, B.M.; Kolkman, J.A.; Beintema, J.J

    2003-01-01

    There have been many studies on the chemistry of mammalian pancreatic ribonucleases (ribonucleases 1), but the functional biology of this family of homologous proteins is still largely unknown. Many studies have been performed on the molecular evolution and properties of this enzyme from species bel

  19. Mirror Neurons and the Evolution of Language

    Science.gov (United States)

    Corballis, Michael C.

    2010-01-01

    The mirror system provided a natural platform for the subsequent evolution of language. In nonhuman primates, the system provides for the understanding of biological action, and possibly for imitation, both prerequisites for language. I argue that language evolved from manual gestures, initially as a system of pantomime, but with gestures…

  20. Evolution and non-equilibrium physics

    DEFF Research Database (Denmark)

    Becker, Nikolaj; Sibani, Paolo

    2014-01-01

    We argue that the stochastic dynamics of interacting agents which replicate, mutate and die constitutes a non-equilibrium physical process akin to aging in complex materials. Specifically, our study uses extensive computer simulations of the Tangled Nature Model (TNM) of biological evolution...

  1. Phylogeny and evolution of RNA structure.

    Science.gov (United States)

    Gesell, Tanja; Schuster, Peter

    2014-01-01

    Darwin's conviction that all living beings on Earth are related and the graph of relatedness is tree-shaped has been essentially confirmed by phylogenetic reconstruction first from morphology and later from data obtained by molecular sequencing. Limitations of the phylogenetic tree concept were recognized as more and more sequence information became available. The other path-breaking idea of Darwin, natural selection of fitter variants in populations, is cast into simple mathematical form and extended to mutation-selection dynamics. In this form the theory is directly applicable to RNA evolution in vitro and to virus evolution. Phylogeny and population dynamics of RNA provide complementary insights into evolution and the interplay between the two concepts will be pursued throughout this chapter. The two strategies for understanding evolution are ultimately related through the central paradigm of structural biology: sequence ⇒ structure ⇒ function. We elaborate on the state of the art in modeling both phylogeny and evolution of RNA driven by reproduction and mutation. Thereby the focus will be laid on models for phylogenetic sequence evolution as well as evolution and design of RNA structures with selected examples and notes on simulation methods. In the perspectives an attempt is made to combine molecular structure, population dynamics, and phylogeny in modeling evolution.

  2. The middle way of evolution.

    Science.gov (United States)

    Hunt, Tam

    2012-09-01

    THIS ESSAY PROVIDES A CRITICAL REVIEW OF TWO RECENT BOOKS ON EVOLUTION: Richard Dawkins' The Greatest Show on Earth, and Jerry Coyne's Why Evolution is True, as well as a critique of mainstream evolutionary theory and of natural selection. I also suggest a generalization of sexual selection theory that acknowledges mind as pervasive in nature. Natural selection, as the primary theory of how biological change occurs, must be carefully framed to avoid the long-standing "tautology problem" and must also be modified to more explicitly include the role of mind in evolution. A propensity approach to natural selection, in which "expected fitness" is utilized rather than "fitness," can save natural selection from tautology. But to be a productive theory, natural selection theory should be placed alongside sexual selection - which is explicitly agentic/intentional - as a twin force, but also placed alongside purely endogenous factors such as genetic drift. This framing is contrary to the normal convention that often groups all of these factors under the rubric of "natural selection." I suggest some approaches for improving modern evolutionary theory, including a "generalized sexual selection," a panpsychist extension of Darwin's theory of sexual selection that explicitly recognizes the role of mind at all levels of nature and which may play the part of a general theory of evolution better than natural selection theory.

  3. Social evolution in multispecies biofilms.

    Science.gov (United States)

    Mitri, Sara; Xavier, João B; Foster, Kevin R

    2011-06-28

    Microbial ecology is revealing the vast diversity of strains and species that coexist in many environments, ranging from free-living communities to the symbionts that compose the human microbiome. In parallel, there is growing evidence of the importance of cooperative phenotypes for the growth and behavior of microbial groups. Here we ask: How does the presence of multiple species affect the evolution of cooperative secretions? We use a computer simulation of spatially structured cellular groups that captures key features of their biology and physical environment. When nutrient competition is strong, we find that the addition of new species can inhibit cooperation by eradicating secreting strains before they can become established. When nutrients are abundant and many species mix in one environment, however, our model predicts that secretor strains of any one species will be surrounded by other species. This "social insulation" protects secretors from competition with nonsecretors of the same species and can improve the prospects of within-species cooperation. We also observe constraints on the evolution of mutualistic interactions among species, because it is difficult to find conditions that simultaneously favor both within- and among-species cooperation. Although relatively simple, our model reveals the richness of interactions between the ecology and social evolution of multispecies microbial groups, which can be critical for the evolution of cooperation.

  4. Modelling language evolution: Examples and predictions

    Science.gov (United States)

    Gong, Tao; Shuai, Lan; Zhang, Menghan

    2014-06-01

    We survey recent computer modelling research of language evolution, focusing on a rule-based model simulating the lexicon-syntax coevolution and an equation-based model quantifying the language competition dynamics. We discuss four predictions of these models: (a) correlation between domain-general abilities (e.g. sequential learning) and language-specific mechanisms (e.g. word order processing); (b) coevolution of language and relevant competences (e.g. joint attention); (c) effects of cultural transmission and social structure on linguistic understandability; and (d) commonalities between linguistic, biological, and physical phenomena. All these contribute significantly to our understanding of the evolutions of language structures, individual learning mechanisms, and relevant biological and socio-cultural factors. We conclude the survey by highlighting three future directions of modelling studies of language evolution: (a) adopting experimental approaches for model evaluation; (b) consolidating empirical foundations of models; and (c) multi-disciplinary collaboration among modelling, linguistics, and other relevant disciplines.

  5. Modelling language evolution: Examples and predictions.

    Science.gov (United States)

    Gong, Tao; Shuai, Lan; Zhang, Menghan

    2014-06-01

    We survey recent computer modelling research of language evolution, focusing on a rule-based model simulating the lexicon-syntax coevolution and an equation-based model quantifying the language competition dynamics. We discuss four predictions of these models: (a) correlation between domain-general abilities (e.g. sequential learning) and language-specific mechanisms (e.g. word order processing); (b) coevolution of language and relevant competences (e.g. joint attention); (c) effects of cultural transmission and social structure on linguistic understandability; and (d) commonalities between linguistic, biological, and physical phenomena. All these contribute significantly to our understanding of the evolutions of language structures, individual learning mechanisms, and relevant biological and socio-cultural factors. We conclude the survey by highlighting three future directions of modelling studies of language evolution: (a) adopting experimental approaches for model evaluation; (b) consolidating empirical foundations of models; and (c) multi-disciplinary collaboration among modelling, linguistics, and other relevant disciplines.

  6. The Imperatives of Cosmic Biology

    CERN Document Server

    Gibson, Carl H

    2010-01-01

    The transformation of organic molecules into the simplest self-replicating living system,a microorganism, is accomplished from a unique event or rare events that occurred early in the Universe. The subsequent dispersal on cosmic scales and evolution of life is guaranteed, being determined by well-understood processes of physics and biology. Entire galaxies and clusters of galaxies can be considered as connected biospheres, with lateral gene transfers, as initially theorized by Joseph (2000), providing for genetic mixing and Darwinian evolution on a cosmic scale. Big bang cosmology modified by modern fluid mechanics suggests the beginning and wide intergalactic dispersal of life occurred immediately after the end of the plasma epoch when the gas of protogalaxies in clusters fragmented into clumps of planets. Stars are born from binary mergers of such planets within such clumps. When stars devour their surrounding planets to excess they explode, distributing necessary fertilizing chemicals created only in stars...

  7. Endosymbiosis and Eukaryotic Cell Evolution.

    Science.gov (United States)

    Archibald, John M

    2015-10-05

    Understanding the evolution of eukaryotic cellular complexity is one of the grand challenges of modern biology. It has now been firmly established that mitochondria and plastids, the classical membrane-bound organelles of eukaryotic cells, evolved from bacteria by endosymbiosis. In the case of mitochondria, evidence points very clearly to an endosymbiont of α-proteobacterial ancestry. The precise nature of the host cell that partnered with this endosymbiont is, however, very much an open question. And while the host for the cyanobacterial progenitor of the plastid was undoubtedly a fully-fledged eukaryote, how - and how often - plastids moved from one eukaryote to another during algal diversification is vigorously debated. In this article I frame modern views on endosymbiotic theory in a historical context, highlighting the transformative role DNA sequencing played in solving early problems in eukaryotic cell evolution, and posing key unanswered questions emerging from the age of comparative genomics.

  8. [Classification of organisms and structuralism in biology].

    Science.gov (United States)

    Vasil'eva, L I

    2001-01-01

    Structuralism in biology is the oldest trend oriented to the search for natural "laws of forms" comparable with laws of growth of crystal, was revived at the end of 20th century on the basis of structuralist thought in socio-humanitarian sciences. The development of principal ideas of the linguistic structuralism in some aspects is similar to that of biological systematics, especially concerning the relationships between "system" and "evolution". However, apart from this general similarity, biological structuralism is strongly focused on familiar problems of the origin of diversity in nature. In their striving for the renovation of existing views, biological structuralists oppose the neo-darwinism emphasizing the existence of "law of forms", that are independent on heredity and genetic "determinism". The trend to develop so-called "rational taxonomy" is also characteristic of biological structuralism but this attempt failed being connected neither with Darwin's historicism nor with Plato's typology.

  9. Cell biology perspectives in phage biology.

    Science.gov (United States)

    Ansaldi, Mireille

    2012-01-01

    Cellular biology has long been restricted to large cellular organisms. However, as the resolution of microscopic methods increased, it became possible to study smaller cells, in particular bacterial cells. Bacteriophage biology is one aspect of bacterial cell biology that has recently gained insight from cell biology. Despite their small size, bacteriophages could be successfully labeled and their cycle studied in the host cells. This review aims to put together, although non-extensively, several cell biology studies that recently pushed the elucidation of key mechanisms in phage biology, such as the lysis-lysogeny decision in temperate phages or genome replication and transcription, one step further.

  10. Evolution prediction from tomography

    Science.gov (United States)

    Dominy, Jason M.; Venuti, Lorenzo Campos; Shabani, Alireza; Lidar, Daniel A.

    2017-03-01

    Quantum process tomography provides a means of measuring the evolution operator for a system at a fixed measurement time t. The problem of using that tomographic snapshot to predict the evolution operator at other times is generally ill-posed since there are, in general, infinitely many distinct and compatible solutions. We describe the prediction, in some "maximal ignorance" sense, of the evolution of a quantum system based on knowledge only of the evolution operator for finitely many times 0evolution at times away from the measurement times. Even if the original evolution is unitary, the predicted evolution is described by a non-unitary, completely positive map.

  11. Condensed Matter Physics - Biology Resonance

    Science.gov (United States)

    Baskaran, G.

    The field of condensed matter physics had its genesis this century and it has had a remarkable evolution. A closer look at its growth reveals a hidden aim in the collective consciousness of the field - a part of the development this century is a kind of warm up exercise to understand the nature of living condensed matter, namely the field of biology, by a growing new breed of scientists in the coming century. Through some examples the vitality of this interaction will be pointed out.

  12. Foundational issues in evolution education

    Science.gov (United States)

    Smith, Mike U.; Siegel, Harvey; McInerney, Joseph D.

    1995-01-01

    There is a great need for effective evolution education. This paper reviews some of the evidence that demonstrates that need and analyzes some of the foundational semantic, epistemological, and philosophical issues involved. This analysis is used to provide a functional understanding of the distinction between science and non-science. Special emphasis is placed the scientific meaning of the terms theory, hypothesis, fact, proof, evidence, and truth, focusing on the difference between religious belief and acceptance of a scientific theory. Science is viewed as theologically neutral and as not mutually exclusive from religion. Finally, a number of practical recommendations to the classroom biology teacher are presented.

  13. The Criticism of Atheistic Evolution

    Directory of Open Access Journals (Sweden)

    Dr Farah Ramin

    2010-01-01

    Full Text Available With regard to close relation between evolution theory and religious knowledge, and its prodigious influence on arising new schools in philosophy; this paper firstly considers the outcome of Darwin’s theologian theory in brief; secondly it talks about recent controversies such as: ambiguity of Fitness concept, tautology and the usage of probability calculation in this theory,opposition of the second law of thermodynamics (Entropy, biological information in DNA, irreducible complexity, Fine-tuning of decisive nature constant and Anthropic Principle.

  14. The Criticism of Atheistic Evolution

    Directory of Open Access Journals (Sweden)

    Farah Ramin

    2010-04-01

    Full Text Available  With regard to close relation between evolution theory and religious knowledge, and its prodigious influence on arising new schools in philosophy this paper firstly considers the outcome of Darwin’s theologian theory in brief secondly it talks about recent controversies such as: ambiguity of Fitness concept, tautology and the usage of probability calculation in this theory,opposition of the second law of thermodynamics (Entropy, biological information in DNA, irreducible complexity, Fine-tuning of decisive nature constant and Anthropic Principle .

  15. Research on Bacteria in the Mainstream of Biology.

    Science.gov (United States)

    Magasanik, Boris

    1988-01-01

    Stresses the importance of investigating bacterial mechanisms to discover clues for a greater understanding of cells. Cites examples of study areas of biological significance which may reveal information about the evolution of prokaryotes and eukaryotes and lead to a comprehensive theory of cell biology. (RT)

  16. "Reinventing Life": Introductory Biology for a Rapidly Evolving World

    Science.gov (United States)

    Coker, Jeffrey Scott

    2009-01-01

    Evolutionary concepts are essential for a scientific understanding of most issues surrounding modern medicine, agriculture, biotechnology, and the environment. If the mantra for biology education in the 20th century was, "Nothing in biology makes sense except in the light of evolution," the mantra for the 21st century must be, "Nothing in biology…

  17. Modeling of Biological Intelligence for SCM System Optimization

    OpenAIRE

    Shengyong Chen; Yujun Zheng; Carlo Cattani; Wanliang Wang

    2012-01-01

    This article summarizes some methods from biological intelligence for modeling and optimization of supply chain management (SCM) systems, including genetic algorithms, evolutionary programming, differential evolution, swarm intelligence, artificial immune, and other biological intelligence related methods. An SCM system is adaptive, dynamic, open self-organizing, which is maintained by flows of information, materials, goods, funds, and energy. Traditional methods for modeling and optimizing c...

  18. Teaching biology with model organisms

    Science.gov (United States)

    Keeley, Dolores A.

    The purpose of this study is to identify and use model organisms that represent each of the kingdoms biologists use to classify organisms, while experiencing the process of science through guided inquiry. The model organisms will be the basis for studying the four high school life science core ideas as identified by the Next Generation Science Standards (NGSS): LS1-From molecules to organisms, LS2-Ecosystems, LS3- Heredity, and LS4- Biological Evolution. NGSS also have identified four categories of science and engineering practices which include developing and using models and planning and carrying out investigations. The living organisms will be utilized to increase student interest and knowledge within the discipline of Biology. Pre-test and posttest analysis utilizing student t-test analysis supported the hypothesis. This study shows increased student learning as a result of using living organisms as models for classification and working in an inquiry-based learning environment.

  19. Stable States of Biological Organisms

    CERN Document Server

    Yukalov, V I; Yukalova, E P; Henry, J -Y; Cobb, J P

    2009-01-01

    A novel model of biological organisms is advanced, treating an organism as a self-consistent system subject to a pathogen flux. The principal novelty of the model is that it describes not some parts, but a biological organism as a whole. The organism is modeled by a five-dimensional dynamical system. The organism homeostasis is described by the evolution equations for five interacting components: healthy cells, ill cells, innate immune cells, specific immune cells, and pathogens. The stability analysis demonstrates that, in a wide domain of the parameter space, the system exhibits robust structural stability. There always exist four stable stationary solutions characterizing four qualitatively differing states of the organism: alive state, boundary state, critical state, and dead state.

  20. Thinking Evolutionarily: Evolution Education across the Life Sciences--Summary of a Convocation

    Science.gov (United States)

    Olson, Steve

    2012-01-01

    Evolution is the central unifying theme of biology. Yet today, more than a century and a half after Charles Darwin proposed the idea of evolution through natural selection, the topic is often relegated to a handful of chapters in textbooks and a few class sessions in introductory biology courses, if covered at all. In recent years, a movement has…

  1. Tuition vs. Intuition: Effects of Instruction on Naive Theories of Evolution

    Science.gov (United States)

    Shtulman, Andrew; Calabi, Prassede

    2013-01-01

    Recent research suggests that a major obstacle to evolution understanding is an essentialist view of the biological world. The present study investigated the effects of formal biology instruction on such misconceptions. Participants (N = 291) completed an assessment of their understanding of six aspects of evolution (variation, inheritance,…

  2. The Synthetic Biology Open Language (SBOL) provides a community standard for communicating designs in synthetic biology.

    Science.gov (United States)

    Galdzicki, Michal; Clancy, Kevin P; Oberortner, Ernst; Pocock, Matthew; Quinn, Jacqueline Y; Rodriguez, Cesar A; Roehner, Nicholas; Wilson, Mandy L; Adam, Laura; Anderson, J Christopher; Bartley, Bryan A; Beal, Jacob; Chandran, Deepak; Chen, Joanna; Densmore, Douglas; Endy, Drew; Grünberg, Raik; Hallinan, Jennifer; Hillson, Nathan J; Johnson, Jeffrey D; Kuchinsky, Allan; Lux, Matthew; Misirli, Goksel; Peccoud, Jean; Plahar, Hector A; Sirin, Evren; Stan, Guy-Bart; Villalobos, Alan; Wipat, Anil; Gennari, John H; Myers, Chris J; Sauro, Herbert M

    2014-06-01

    The re-use of previously validated designs is critical to the evolution of synthetic biology from a research discipline to an engineering practice. Here we describe the Synthetic Biology Open Language (SBOL), a proposed data standard for exchanging designs within the synthetic biology community. SBOL represents synthetic biology designs in a community-driven, formalized format for exchange between software tools, research groups and commercial service providers. The SBOL Developers Group has implemented SBOL as an XML/RDF serialization and provides software libraries and specification documentation to help developers implement SBOL in their own software. We describe early successes, including a demonstration of the utility of SBOL for information exchange between several different software tools and repositories from both academic and industrial partners. As a community-driven standard, SBOL will be updated as synthetic biology evolves to provide specific capabilities for different aspects of the synthetic biology workflow.

  3. Evolution from Cellular to Social Scales

    CERN Document Server

    Skjeltorp, Arne T

    2008-01-01

    Evolution is a critical challenge for many areas of science, technology and development of society. The book reviews general evolutionary facts such as origin of life and evolution of the genome and clues to evolution through simple systems. Emerging areas of science such as "systems biology" and "bio-complexity" are founded on the idea that phenomena need to be understood in the context of highly interactive processes operating at different levels and on different scales. This is where physics meets complexity in nature, and where we must begin to learn about complexity if we are to understand it. Similarly, there is an increasingly urgent need to understand and predict the evolutionary behavior of highly interacting man-made systems, in areas such as communications and transport, which permeate the modern world. The same applies to the evolution of human networks such as social, political and financial systems, where technology has tended to vastly increase both the complexity and speed of interaction, whic...

  4. Art as A Playground for Evolution

    DEFF Research Database (Denmark)

    Beloff, Laura

    2016-01-01

    Art works which engage with the topic of human enhancement and evolution have begun appearing parallel to increased awareness about anthropogenic changes to our environment and acceleration of the speed of technological developments that impact us and our biological environment. The article...... connects artistic activity with play activity and evolution, which are considered on two levels. On the first level, play activity and its beneficial role to evolution is introduced through various science scholars’ research. On the second level, artistic activity that engages with human enhancement...... and related topics is proposed as play activity for adults, which simultaneously experiments directly with ideas concerning evolution and human development. The author proposes that these kinds of experimental art projects support our mental adaptation to evolutionary changes....

  5. Positioning Genomics in Biology Education: Content Mapping of Undergraduate Biology Textbooks

    Directory of Open Access Journals (Sweden)

    Naomi L. B. Wernick

    2014-07-01

    Full Text Available Biological thought increasingly recognizes the centrality of the genome in constituting and regulating processes ranging from cellular systems to ecology and evolution. In this paper, we ask whether genomics is similarly positioned as a core concept in the instructional sequence for undergraduate biology. Using quantitative methods, we analyzed the order in which core biological concepts were introduced in textbooks for first-year general and human biology. Statistical analysis was performed using self-organizing map algorithms and conventional methods to identify clusters of terms and their relative position in the books. General biology textbooks for both majors and nonmajors introduced genome-related content after text related to cell biology and biological chemistry, but before content describing higher-order biological processes. However, human biology textbooks most often introduced genomic content near the end of the books. These results suggest that genomics is not yet positioned as a core concept in commonly used textbooks for first-year biology and raises questions about whether such textbooks, or courses based on the outline of these textbooks, provide an appropriate foundation for understanding contemporary biological science.

  6. Molecular biology of Homo sapiens: Abstracts of papers presented at the 51st Cold Spring Harbor symposium on quantitative biology

    Energy Technology Data Exchange (ETDEWEB)

    Watson, J.D.; Siniscalco, M.

    1986-01-01

    This volume contains abstracts of papers presented at the 51st Cold Springs Harbor Symposium on Quantitative Biology. The topic for this meeting was the ''Molecular Biology of Homo sapiens.'' Sessions were entitled Human Gene Map, Human Cancer Genes, Genetic Diagnosis, Human Evolution, Drugs Made Off Human Genes, Receptors, and Gene Therapy. (DT)

  7. Computational Modeling of Biological Systems From Molecules to Pathways

    CERN Document Server

    2012-01-01

    Computational modeling is emerging as a powerful new approach for studying and manipulating biological systems. Many diverse methods have been developed to model, visualize, and rationally alter these systems at various length scales, from atomic resolution to the level of cellular pathways. Processes taking place at larger time and length scales, such as molecular evolution, have also greatly benefited from new breeds of computational approaches. Computational Modeling of Biological Systems: From Molecules to Pathways provides an overview of established computational methods for the modeling of biologically and medically relevant systems. It is suitable for researchers and professionals working in the fields of biophysics, computational biology, systems biology, and molecular medicine.

  8. Is evolutionary biology strategic science?

    Science.gov (United States)

    Meagher, Thomas R

    2007-01-01

    There is a profound need for the scientific community to be better aware of the policy context in which it operates. To address this need, Evolution has established a new Outlook feature section to include papers that explore the interface between society and evolutionary biology. This first paper in the series considers the strategic relevance of evolutionary biology. Support for scientific research in general is based on governmental or institutional expenditure that is an investment, and such investment is based on strategies designed to achieve particular outcomes, such as advance in particular areas of basic science or application. The scientific community can engage in the development of scientific strategies on a variety of levels, including workshops to explicitly develop research priorities and targeted funding initiatives to help define emerging scientific areas. Better understanding and communication of the scientific achievements of evolutionary biology, emphasizing immediate and potential societal relevance, are effective counters to challenges presented by the creationist agenda. Future papers in the Outlook feature section should assist the evolutionary biology community in achieving a better collective understanding of the societal relevance of their field.

  9. [Biology molecular of glioblastomas].

    Science.gov (United States)

    Franco-Hernández, C; Martínez-Glez, V; Rey, J A

    2007-10-01

    Glioblastomas, the most frequent and malignant human brain tumors, may develop de novo (primary glioblastoma) or by progression from low-grade or anapalsic astrocytoma (secondary glioblastoma). The molecular alteration most frequent in these tumor-like types is the loss of heterozygosity on chromosome 10, in which several genes have been identified as tumors suppressor. The TP53/MDM2/P14arf and CDK4/RB1/ P16ink4 genetic pathways involved in cycle control are deregulated in the majority of gliomas as well as genes that promote the cellular division, EGFR. Finally the increase of growth and angiogenics factors is also involved in the development of glioblastomas. One of the objectives of molecular biology in tumors of glial ancestry is to try to find the genetic alterations that allow to approach better the classification of glioblastomas, its evolution prediction and treatment. The new pathmolecular classification of gliomas should improve the old one, especially being concerned about the oncogenesis and heterogeneity of these tumors. It is desirable that this classification had clinical applicability and integrates new molecular findings with some known histological features with pronostic value. In this paper we review the most frequent molecular mechanisms involved in the patogenesis of glioblastomas.

  10. Conceptual Ecology of the Evolution Acceptance among Greek Education Students: Knowledge, Religious Practices and Social Influences

    Science.gov (United States)

    Athanasiou, Kyriacos; Papadopoulou, Penelope

    2012-01-01

    In this study, we explored some of the factors related to the acceptance of evolution theory among Greek university students training to be teachers in early childhood education, using conceptual ecology for biological evolution as a theoretical framework. We examined the acceptance of evolution theory and we also looked into the relationship…

  11. Mother Knows Best: Epigenetic Inheritance, Maternal Effects, and the Evolution of Human Intelligence

    Science.gov (United States)

    Bjorklund, David F.

    2006-01-01

    Contemporary evolution biology has recognized the role of development in evolution. Evolutionarily oriented psychologists have similarly recognized the role that behavioral plasticity, particularly early in development, may have had on the evolution of species, harking back to the ideas of Baldwin (the Baldwin effect). Epigenetic theories of…

  12. Freud and evolution.

    Science.gov (United States)

    Scharbert, Gerhard

    2009-01-01

    The essay analyzes the influence of evolutionary thought in the work of Sigmund Freud. Based on Freud's initial occupation as a neuro-anatomist and physiologist certain aspects stemming from the history of nature and developmental biological reasoning that played a role in his endeavours to find a new basis for medical psychology will be pointed out. These considerations are to be regarded as prolegomena of the task to reread Freud once again, and in doing so avoiding the verdict that holds his neuro-anatomic and comparative-morphological works as simply "pre-analytic." In fact, the time seems ripe to reconsider in a new context particularly those evolutionary, medical, and cultural-scientific elements in Freud's work that appear inconsistent at first sight. The substantial thesis is that Freud, given the fact that he was trained in comparative anatomy and physiology in the tradition of Johannes Müller, had the capability of synthesizing elements of this new point of view with the findings and interrogations concerning developmental history and the theory of evolution. More over, this was perceived not merely metaphoric, as he himself stressed it (Freud 1999, XIII, 99), but in the sense of Ubertragung, that inscribed terms and methods deriving from the given field into the realm of psychology. The moving force behind this particular Ubertragung came from a dynamically-neurological perception of the soul that emerged in France since 1800, which Freud came to know trough the late work of Charcot.

  13. First International Conference on the Evolution and Development of the Universe

    CERN Document Server

    EDU2008

    2009-01-01

    This document is the Special Issue of the First International Conference on the Evolution and Development (EDU 2008). Please refer to the preface and introduction for more details on the contributions. Keywords: acceleration, artificial cosmogenesis, artificial life, Big Bang, Big History, biological evolution, biological universe, biology, causality, classical vacuum energy, complex systems, complexity, computational universe, conscious evolution, cosmological artificial selection, cosmological natural selection, cosmology, critique, cultural evolution, dark energy, dark matter, development of the universe, development, emergence, evolution of the universe evolution, exobiology, extinction, fine-tuning, fractal space-time, fractal, information, initial conditions, intentional evolution, linear expansion of the universe, log-periodic laws, macroevolution, materialism, meduso-anthropic principle, multiple worlds, natural sciences, Nature, ontology, order, origin of the universe, particle hierarchy, philosophy,...

  14. Biological warfare agents.

    Science.gov (United States)

    Pohanka, Miroslav; Kuca, Kamil

    2010-01-01

    Biological warfare agents are a group of pathogens and toxins of biological origin that can be potentially misused for military or criminal purposes. The present review attempts to summarize necessary knowledge about biological warfare agents. The historical aspects, examples of applications of these agents such as anthrax letters, biological weapons impact, a summary of biological warfare agents and epidemiology of infections are described. The last section tries to estimate future trends in research on biological warfare agents.

  15. AGENTS OF CHANGE: MODELING BIOCULTURAL EVOLUTION IN UPPER PLEISTOCENE WESTERN EURASIA

    OpenAIRE

    C. Michael. Barton; JULIEN RIEL-SALVATORE

    2012-01-01

    The complex interactions between social learning and biological change are key to understanding the human species and its origins. Yet paleoanthropological models often focus only on the evolution of the human genome and physical characters, while behavior is treated as an epiphenomenon of biological evolution. We present the results of a series of experiments that use computational models, parametrized with new archaeological data, to simulate the complex dynamics of human biocultural evolut...

  16. Directed evolution of aldolases for exploitation in synthetic organic chemistry

    Science.gov (United States)

    Bolt, Amanda; Berry, Alan; Nelson, Adam

    2008-01-01

    This review focuses on the directed evolution of aldolases with synthetically useful properties. Directed evolution has been used to address a number of limitations associated with the use of wild-type aldolases as catalysts in synthetic organic chemistry. The generation of aldolase enzymes with a modified or expanded substrate repertoire is described. Particular emphasis is placed on the directed evolution of aldolases with modified stereochemical properties: such enzymes can be useful catalysts in the stereoselective synthesis of biologically active small molecules. The review also describes some of the fundamental insights into mechanistic enzymology that directed evolution can provide. PMID:18230325

  17. Evolution of species from Darwin theory: A simple model

    Science.gov (United States)

    Moret, M. A.; Pereira, H. B. B.; Monteiro, S. L.; Galeão, A. C.

    2012-04-01

    Evolution of species is a complex phenomenon. Some theoretical models take into account evolution of species, like the Bak-Sneppen model that obtain punctuated equilibrium from self-organized criticality and the Penna model for biological aging that consists in a bit-string model subjected to aging, reproduction and death. In this work we propose a simple model to study different scenarios used to simulate the evolution of species. This model is based on Darwin's ideas of evolution. The present findings show that punctuated equilibria and stasis seem to be obtained directly from the mutation, selection of parents and the genetic crossover, and are very close to the fossil data analysis.

  18. Protein structure and neutral theory of evolution.

    Science.gov (United States)

    Ptitsyn, O B; Volkenstein, M V

    1986-08-01

    The neutral theory of evolution is extended to the origin of protein molecules. Arguments are presented which suggest that the amino acid sequences of many globular proteins mainly represent "memorized" random sequences while biological evolution reduces to the "editing" these random sequences. Physical requirements for a functional globular protein are formulated and it is shown that many of these requirement do not involve strategical selection of amino acid sequences during biological evolution but are inherent also for typical random sequences. In particular, it is shown that random sequences of polar and amino acid residues can form alpha-helices and beta-strand with lengths and arrangement along the chain similar to those in real globular proteins. These alpha- and beta-regions in random sequences can form three-dimensional folding patterns also similar to those in proteins. The arguments are presented suggesting that even the tight packing of side groups inside protein core do not require very strong biological selection of amino acid sequences either. Thus many structural features of real proteins can exist also in random sequences and the biological selection is needed mainly for the creation of active site of protein and for their stability under physiological conditions.

  19. Teaching Evolution to Students with Compromised Backgrounds & Lack of Confidence about Evolution--Is It Possible?

    Science.gov (United States)

    Schauer, Alexandria; Cotner, Sehoya; Moore, Randy

    2014-01-01

    Students regard evolutionary theory differently than science in general. Students' reported confidence in their ability to understand science in general (e.g., posing scientific questions, interpreting tables and graphs, and understanding the content of their biology course) significantly outweighed their confidence in understanding evolution. We…

  20. The 1st Symposium on Chemical Evolution and the Origin and Evolution of Life

    Science.gov (United States)

    Devincenzi, D. L. (Editor); Pleasant, L. G. (Editor)

    1982-01-01

    This symposium provided an opportunity for all NASA Exobiology principal investigators to present their most recent research in a scientific meeting forum. Papers were presented in the following exobiology areas: extraterrestrial chemistry primitive earth, information transfer, solar system exploration, planetary protection, geological record, and early biological evolution.

  1. Evolution and biogeography of gymnosperms.

    Science.gov (United States)

    Wang, Xiao-Quan; Ran, Jin-Hua

    2014-06-01

    Living gymnosperms comprise only a little more than 1000 species, but represent four of the five main lineages of seed plants, including cycads, ginkgos, gnetophytes and conifers. This group has huge ecological and economic value, and has drawn great interest from the scientific community. Here we review recent advances in our understanding of gymnosperm evolution and biogeography, including phylogenetic relationships at different taxonomic levels, patterns of species diversification, roles of vicariance and dispersal in development of intercontinental disjunctions, modes of molecular evolution in different genomes and lineages, and mechanisms underlying the formation of large nuclear genomes. It is particularly interesting that increasing evidence supports a sister relationship between Gnetales and Pinaceae (the Gnepine hypothesis) and the contribution of recent radiations to present species diversity, and that expansion of retrotransposons is responsible for the large and complex nuclear genome of gymnosperms. In addition, multiple coniferous genera such as Picea very likely originated in North America and migrated into the Old World, further indicating that the center of diversity is not necessarily the place of origin. The Bering Land Bridge acted as an important pathway for dispersal of gymnosperms in the Northern Hemisphere. Moreover, the genome sequences of conifers provide an unprecedented opportunity and an important platform for the evolutionary studies of gymnosperms, and will also shed new light on evolution of many important gene families and biological pathways in seed plants.

  2. Genome increase as a clock for the origin and evolution of life

    OpenAIRE

    Sharov Alexei A

    2006-01-01

    Abstract Background The size of non-redundant functional genome can be an indicator of biological complexity of living organisms. Several positive feedback mechanisms including gene cooperation and duplication with subsequent specialization may result in the exponential growth of biological complexity in macro-evolution. Results I propose a hypothesis that biological complexity increased exponentially during evolution. Regression of the logarithm of functional non-redundant genome size versus...

  3. The Biology of Intron Gain and Loss

    DEFF Research Database (Denmark)

    Jeffares, Daniel C; Mourier, Tobias; Penny, David

    2006-01-01

    Intron density in eukaryote genomes varies by more than three orders of magnitude, so there must have been extensive intron gain and/or intron loss during evolution. A favored and partial explanation for this range of intron densities has been that introns have accumulated stochastically in large...... eukaryote genomes during their evolution from an intron-poor ancestor. However, recent studies have shown that some eukaryotes lost many introns, whereas others accumulated and/or gained many introns. In this article, we discuss the growing evidence that these differences are subject to selection acting...... on introns depending on the biology of the organism and the gene involved....

  4. A first attempt to bring computational biology into advanced high school biology classrooms.

    Directory of Open Access Journals (Sweden)

    Suzanne Renick Gallagher

    2011-10-01

    Full Text Available Computer science has become ubiquitous in many areas of biological research, yet most high school and even college students are unaware of this. As a result, many college biology majors graduate without adequate computational skills for contemporary fields of biology. The absence of a computational element in secondary school biology classrooms is of growing concern to the computational biology community and biology teachers who would like to acquaint their students with updated approaches in the discipline. We present a first attempt to correct this absence by introducing a computational biology element to teach genetic evolution into advanced biology classes in two local high schools. Our primary goal was to show students how computation is used in biology and why a basic understanding of computation is necessary for research in many fields of biology. This curriculum is intended to be taught by a computational biologist who has worked with a high school advanced biology teacher to adapt the unit for his/her classroom, but a motivated high school teacher comfortable with mathematics and computing may be able to teach this alone. In this paper, we present our curriculum, which takes into consideration the constraints of the required curriculum, and discuss our experiences teaching it. We describe the successes and challenges we encountered while bringing this unit to high school students, discuss how we addressed these challenges, and make suggestions for future versions of this curriculum.We believe that our curriculum can be a valuable seed for further development of computational activities aimed at high school biology students. Further, our experiences may be of value to others teaching computational biology at this level. Our curriculum can be obtained at http://ecsite.cs.colorado.edu/?page_id=149#biology or by contacting the authors.

  5. A first attempt to bring computational biology into advanced high school biology classrooms.

    Science.gov (United States)

    Gallagher, Suzanne Renick; Coon, William; Donley, Kristin; Scott, Abby; Goldberg, Debra S

    2011-10-01

    Computer science has become ubiquitous in many areas of biological research, yet most high school and even college students are unaware of this. As a result, many college biology majors graduate without adequate computational skills for contemporary fields of biology. The absence of a computational element in secondary school biology classrooms is of growing concern to the computational biology community and biology teachers who would like to acquaint their students with updated approaches in the discipline. We present a first attempt to correct this absence by introducing a computational biology element to teach genetic evolution into advanced biology classes in two local high schools. Our primary goal was to show students how computation is used in biology and why a basic understanding of computation is necessary for research in many fields of biology. This curriculum is intended to be taught by a computational biologist who has worked with a high school advanced biology teacher to adapt the unit for his/her classroom, but a motivated high school teacher comfortable with mathematics and computing may be able to teach this alone. In this paper, we present our curriculum, which takes into consideration the constraints of the required curriculum, and discuss our experiences teaching it. We describe the successes and challenges we encountered while bringing this unit to high school students, discuss how we addressed these challenges, and make suggestions for future versions of this curriculum.We believe that our curriculum can be a valuable seed for further development of computational activities aimed at high school biology students. Further, our experiences may be of value to others teaching computational biology at this level. Our curriculum can be obtained at http://ecsite.cs.colorado.edu/?page_id=149#biology or by contacting the authors.

  6. Developmental systems biology flourishing on new technologies

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Organism development is a systems level process. It has benefited greatly from the recent technological advances in the field of systems biology. DNA microarray, phenome, interactome and transcriptome mapping, the new generation of deep sequencing technologies,and faster and better computational and modeling approaches have opened new frontiers for both systems biologists and developmental biologists to reexamine the old developmental biology questions, such as pattern formation, and to tackle new problems, such as stem cell reprogramming. As showcased in the International Developmental Systems Biology Symposium organized by Chinese Academy of Sciences, developmental systems biology is flourishing in many perspectives, from the evolution of developmental systems, to the underlying genetic and molecular pathways and networks, to the genomic, epigenomic and noncoding levels, to the computational analysis and modeling. We believe that the field will continue to reap rewards into the future with these new approaches.

  7. Evolutionary biology of harvestmen (Arachnida, Opiliones).

    Science.gov (United States)

    Giribet, Gonzalo; Sharma, Prashant P

    2015-01-07

    Opiliones are one of the largest arachnid orders, with more than 6,500 species in 50 families. Many of these families have been erected or reorganized in the last few years since the publication of The Biology of Opiliones. Recent years have also seen an explosion in phylogenetic work on Opiliones, as well as in studies using Opiliones as test cases to address biogeographic and evolutionary questions more broadly. Accelerated activity in the study of Opiliones evolution has been facilitated by the discovery of several key fossils, including the oldest known Opiliones fossil, which represents a new, extinct suborder. Study of the group's biology has also benefited from rapid accrual of genomic resources, particularly with respect to transcriptomes and functional genetic tools. The rapid emergence and utility of Phalangium opilio as a model for evolutionary developmental biology of arthropods serve as demonstrative evidence of a new area of study in Opiliones biology, made possible through transcriptomic data.

  8. [Biological mutualism, concepts and models].

    Science.gov (United States)

    Perru, Olivier

    2011-01-01

    Mutualism is a biological association for a mutual benefit between two different species. In this paper, firstly, we examine the history and signification of mutualism in relation to symbiosis. Then, we consider the link between concepts and models of mutualism. Models of mutualism depend on different concepts we use: If mutualism is situated at populations' level, it will be expressed by Lotka-Volterra models, concerning exclusively populations' size. If mutualism is considered as a resources' exchange or a biological market increasing the fitness of these organisms, it will be described at an individual level by a cost-benefit model. Our analysis will be limited to the history and epistemology of Lotka-Volterra models and we hypothesize that these models are adapted at first to translate dynamic evolutions of mutualism. They render stability or variations of size and assume that there are clear distinctions and a state of equilibrium between populations of different species. Italian mathematician Vito Volterra demonstrated that biological associations consist in a constant relation between some species. In 1931 and 1935, Volterra described the general form of antagonistic or mutualistic biological associations by the same differential equations. We recognize that these equations have been more used to model competition or prey-predator interactions, but a simple sign change allows describing mutualism. The epistemological problem is the following: Volterra's equations help us to conceptualize a global phenomenon. However, mutualistic interactions may have stronger effects away from equilibrium and these effects may be better understood at individual level. We conclude that, between 1985 and 2000, some researchers carried on working and converting Lotka-Volterra models but this description appeared as insufficient. So, other researchers adopted an economical viewpoint, considering mutualism as a biological market.

  9. Communication theory and multicellular biology.

    Science.gov (United States)

    Mian, I S; Rose, C

    2011-04-01

    In this Perspective, we propose that communication theory--a field of mathematics concerned with the problems of signal transmission, reception and processing--provides a new quantitative lens for investigating multicellular biology, ancient and modern. What underpins the cohesive organisation and collective behaviour of multicellular ecosystems such as microbial colonies and communities (microbiomes) and multicellular organisms such as plants and animals, whether built of simple tissue layers (sponges) or of complex differentiated cells arranged in tissues and organs (members of the 35 or so phyla of the subkingdom Metazoa)? How do mammalian tissues and organs develop, maintain their architecture, become subverted in disease, and decline with age? How did single-celled organisms coalesce to produce many-celled forms that evolved and diversified into the varied multicellular organisms in existence today? Some answers can be found in the blueprints or recipes encoded in (epi)genomes, yet others lie in the generic physical properties of biological matter such as the ability of cell aggregates to attain a certain complexity in size, shape, and pattern. We suggest that Lasswell's maxim "Who says what to whom in what channel with what effect" provides a foundation for understanding not only the emergence and evolution of multicellularity, but also the assembly and sculpting of multicellular ecosystems and many-celled structures, whether of natural or human-engineered origin. We explore how the abstraction of communication theory as an organising principle for multicellular biology could be realised. We highlight the inherent ability of communication theory to be blind to molecular and/or genetic mechanisms. We describe selected applications that analyse the physics of communication and use energy efficiency as a central tenet. Whilst communication theory has and could contribute to understanding a myriad of problems in biology, investigations of multicellular biology

  10. Accepting, understanding, teaching, and learning (human) evolution: Obstacles and opportunities.

    Science.gov (United States)

    Pobiner, Briana

    2016-01-01

    Questions about our origin as a species are universal and compelling. Evolution-and in particular human evolution-is a subject that generates intense interest across the world, evidenced by the fact that fossil and DNA discoveries grace the covers of major science journals and magazines as well as other popular print and online media. However, virtually all national polls indicate that the majority of Americans strongly reject biological evolution as a fact-based, well-tested, and robust understanding of the history of life. In the popular mind, no topic in all of science is more contentious or polarizing than evolution and media sources often only serve to magnify this polarization by covering challenges to the teaching of evolution. In the realm of teaching, debates about evolution have shaped textbooks, curricula, standards, and policy. Challenges to accepting and understanding evolution include mistrust and denial of science, cognitive obstacles and misconceptions, language and terminology, and a religious worldview, among others. Teachers, who are on the front lines of these challenges, must be armed with the tools and techniques to teach evolution in formal education settings across grades K-16 in a straightforward, thorough, and sensitive way. Despite the potentially controversial topic of human evolution, growing research is demonstrating that a pedagogical focus on human examples is an effective and engaging way to teach core concepts of evolutionary biology.

  11. Biological conversion system

    Science.gov (United States)

    Scott, C.D.

    A system for bioconversion of organic material comprises a primary bioreactor column wherein a biological active agent (zymomonas mobilis) converts the organic material (sugar) to a product (alcohol), a rejuvenator column wherein the biological activity of said biological active agent is enhanced, and means for circulating said biological active agent between said primary bioreactor column and said rejuvenator column.

  12. The new biology: beyond the Modern Synthesis

    Directory of Open Access Journals (Sweden)

    Oakley Todd H

    2007-11-01

    Full Text Available Abstract Background The last third of the 20th Century featured an accumulation of research findings that severely challenged the assumptions of the "Modern Synthesis" which provided the foundations for most biological research during that century. The foundations of that "Modernist" biology had thus largely crumbled by the start of the 21st Century. This in turn raises the question of foundations for biology in the 21st Century. Conclusion Like the physical sciences in the first half of the 20th Century, biology at the start of the 21st Century is achieving a substantive maturity of theory, experimental tools, and fundamental findings thanks to relatively secure foundations in genomics. Genomics has also forced biologists to connect evolutionary and molecular biology, because these formerly Balkanized disciplines have been brought together as actors on the genomic stage. Biologists are now addressing the evolution of genetic systems using more than the concepts of population biology alone, and the problems of cell biology using more than the tools of biochemistry and molecular biology alone. It is becoming increasingly clear that solutions to such basic problems as aging, sex, development, and genome size potentially involve elements of biological science at every level of organization, from molecule to population. The new biology knits together genomics, bioinformatics, evolutionary genetics, and other such general-purpose tools to supply novel explanations for the paradoxes that undermined Modernist biology. Open Peer Reviewers This article was reviewed by W.F. Doolittle, E.V. Koonin, and J.M. Logsdon. For the full reviews, please go to the Reviewers' Comments section.

  13. Synthetic biology: insights into biological computation.

    Science.gov (United States)

    Manzoni, Romilde; Urrios, Arturo; Velazquez-Garcia, Silvia; de Nadal, Eulàlia; Posas, Francesc

    2016-04-18

    Organisms have evolved a broad array of complex signaling mechanisms that allow them to survive in a wide range of environmental conditions. They are able to sense external inputs and produce an output response by computing the information. Synthetic biology attempts to rationally engineer biological systems in order to perform desired functions. Our increasing understanding of biological systems guides this rational design, while the huge background in electronics for building circuits defines the methodology. In this context, biocomputation is the branch of synthetic biology aimed at implementing artificial computational devices using engineered biological motifs as building blocks. Biocomputational devices are defined as biological systems that are able to integrate inputs and return outputs following pre-determined rules. Over the last decade the number of available synthetic engineered devices has increased exponentially; simple and complex circuits have been built in bacteria, yeast and mammalian cells. These devices can manage and store information, take decisions based on past and present inputs, and even convert a transient signal into a sustained response. The field is experiencing a fast growth and every day it is easier to implement more complex biological functions. This is mainly due to advances in in vitro DNA synthesis, new genome editing tools, novel molecular cloning techniques, continuously growing part libraries as well as other technological advances. This allows that digital computation can now be engineered and implemented in biological systems. Simple logic gates can be implemented and connected to perform novel desired functions or to better understand and redesign biological processes. Synthetic biological digital circuits could lead to new therapeutic approaches, as well as new and efficient ways to produce complex molecules such as antibiotics, bioplastics or biofuels. Biological computation not only provides possible biomedical and

  14. Translational environmental biology: cell biology informing conservation.

    Science.gov (United States)

    Traylor-Knowles, Nikki; Palumbi, Stephen R

    2014-05-01

    Typically, findings from cell biology have been beneficial for preventing human disease. However, translational applications from cell biology can also be applied to conservation efforts, such as protecting coral reefs. Recent efforts to understand the cell biological mechanisms maintaining coral health such as innate immunity and acclimatization have prompted new developments in conservation. Similar to biomedicine, we urge that future efforts should focus on better frameworks for biomarker development to protect coral reefs.

  15. Computational Systems Chemical Biology

    OpenAIRE

    Oprea, Tudor I.; Elebeoba E. May; Leitão, Andrei; Tropsha, Alexander

    2011-01-01

    There is a critical need for improving the level of chemistry awareness in systems biology. The data and information related to modulation of genes and proteins by small molecules continue to accumulate at the same time as simulation tools in systems biology and whole body physiologically-based pharmacokinetics (PBPK) continue to evolve. We called this emerging area at the interface between chemical biology and systems biology systems chemical biology, SCB (Oprea et al., 2007).

  16. Measurement Frontiers in Molecular Biology

    Science.gov (United States)

    Laderman, Stephen

    2009-03-01

    Developments of molecular measurements and manipulations have long enabled forefront research in evolution, genetics, biological development and its dysfunction, and the impact of external factors on the behavior of cells. Measurement remains at the heart of exciting and challenging basic and applied problems in molecular and cell biology. Methods to precisely determine the identity and abundance of particular molecules amongst a complex mixture of similar and dissimilar types require the successful design and integration of multiple steps involving biochemical manipulations, separations, physical probing, and data processing. Accordingly, today's most powerful methods for characterizing life at the molecular level depend on coordinated advances in applied physics, biochemistry, chemistry, computer science, and engineering. This is well illustrated by recent approaches to the measurement of DNA, RNA, proteins, and intact cells. Such successes underlie well founded visions of how molecular biology can further assist in answering compelling scientific questions and in enabling the development of remarkable advances in human health. These visions, in turn, are motivating the interdisciplinary creation of even more comprehensive measurements. As a further and closely related consequence, they are motivating innovations in the conceptual and practical approaches to organizing and visualizing large, complex sets of interrelated experimental results and distilling from those data compelling, informative conclusions.

  17. Complexity, Information and Biological Organisation

    Directory of Open Access Journals (Sweden)

    Attila Grandpierre

    2005-12-01

    Full Text Available Regarding the widespread confusion about the concept and nature of complexity, information and biological organization, we look for some coordinated conceptual considerations corresponding to quantitative measures suitable to grasp the main characteristics of biological complexity. Quantitative measures of algorithmic complexity of supercomputers like Blue Gene/L are compared with the complexity of the brain. We show that both the computer and the brain have a more fundamental, dynamic complexity measure corresponding to the number of operations per second. Recent insights suggest that the origin of complexity may go back to simplicity at a deeper level, corresponding to algorithmic complexity. We point out that for physical systems Ashby’s Law, Kahre’s Law and causal closure of the physical exclude the generation of information, and since genetic information corresponds to instructions, we are faced with a controversy telling that the algorithmic complexity of physics is much lower than the instructions’ complexity of the human DNA: I_algorithmic(physics ~ 10^3 bit << I_instructions(DNA ~ 10^9 bit. Analyzing the genetic complexity we obtain that actually the genetic information corresponds to a deeper than algorithmic level of complexity, putting an even greater emphasis to the information paradox. We show that the resolution of the fundamental information paradox may lie either in the chemical evolution of inheritance in abiogenesis, or in the existence of an autonomous biological principle allowing the production of information beyond physics.

  18. Comparative Cell Biology and Evolution of Annexins in Diplomonads

    Science.gov (United States)

    Einarsson, Elin; Ástvaldsson, Ásgeir; Hultenby, Kjell; Andersson, Jan O.; Svärd, Staffan G.

    2016-01-01

    ABSTRACT Annexins are multifunctional, calcium-binding proteins found in organisms across all kingdoms. Most studies of annexins from single-celled eukaryotes have focused on the alpha-giardins, proteins assigned to the group E annexins, expressed by the diplomonad Giardia intestinalis. We have characterized the annexin gene family in another diplomonad parasite, Spironucleus salmonicida, by phylogenetic and experimental approaches. We constructed a comprehensive phylogeny of the diplomonad group E annexins and found that they are abundant across the group with frequent gene duplications and losses. The annexins of S. salmonicida were found to be related to alpha-giardins but with better-preserved type II Ca2+ coordination sites. Two annexins were confirmed to bind phospholipids in a Ca2+-dependent fashion but with different specificities. Superresolution and confocal microscopy of epitope-tagged S. salmonicida annexins revealed localization to distinct parts of the cytoskeleton and membrane. The ultrastructural details of the localization of several annexins were determined by proximity labeling and transmission electron microscopy. Two annexins localize to a novel cytoskeletal structure in the anterior of the cell. Our results show that the annexin gene family is expanded in diplomonads and that these group E annexins are associated mostly with cytoskeletal and membrane structures. IMPORTANCE Annexins are proteins that associate with phospholipids in a Ca2+-dependent fashion. These proteins have been intensely studied in animals and plants because of their importance in diverse cellular processes, yet very little is known about annexins in single-celled eukaryotes, which represent the largest diversity of organisms. The human intestinal parasite Giardia intestinalis is known to have more annexins than humans, and they contribute to its pathogenic potential. In this study, we investigated the annexin complement in the salmon pathogen Spironucleus salmonicida, a relative of G. intestinalis. We found that S. salmonicida has a large repertoire of annexins and that the gene family has expanded separately across diplomonads, with members showing sequence diversity similar to that seen across kingdom-level groups such as plants and animals. S. salmonicida annexins are prominent components of the cytoskeleton and membrane. Two annexins are associated with a previously unrecognized structure in the anterior of the cell. PMID:27303715

  19. Comparative Cell Biology and Evolution of Annexins in Diplomonads.

    Science.gov (United States)

    Einarsson, Elin; Ástvaldsson, Ásgeir; Hultenby, Kjell; Andersson, Jan O; Svärd, Staffan G; Jerlström-Hultqvist, Jon

    2016-01-01

    Annexins are multifunctional, calcium-binding proteins found in organisms across all kingdoms. Most studies of annexins from single-celled eukaryotes have focused on the alpha-giardins, proteins assigned to the group E annexins, expressed by the diplomonad Giardia intestinalis. We have characterized the annexin gene family in another diplomonad parasite, Spironucleus salmonicida, by phylogenetic and experimental approaches. We constructed a comprehensive phylogeny of the diplomonad group E annexins and found that they are abundant across the group with frequent gene duplications and losses. The annexins of S. salmonicida were found to be related to alpha-giardins but with better-preserved type II Ca(2+) coordination sites. Two annexins were confirmed to bind phospholipids in a Ca(2+)-dependent fashion but with different specificities. Superresolution and confocal microscopy of epitope-tagged S. salmonicida annexins revealed localization to distinct parts of the cytoskeleton and membrane. The ultrastructural details of the localization of several annexins were determined by proximity labeling and transmission electron microscopy. Two annexins localize to a novel cytoskeletal structure in the anterior of the cell. Our results show that the annexin gene family is expanded in diplomonads and that these group E annexins are associated mostly with cytoskeletal and membrane structures. IMPORTANCE Annexins are proteins that associate with phospholipids in a Ca(2+)-dependent fashion. These proteins have been intensely studied in animals and plants because of their importance in diverse cellular processes, yet very little is known about annexins in single-celled eukaryotes, which represent the largest diversity of organisms. The human intestinal parasite Giardia intestinalis is known to have more annexins than humans, and they contribute to its pathogenic potential. In this study, we investigated the annexin complement in the salmon pathogen Spironucleus salmonicida, a relative of G. intestinalis. We found that S. salmonicida has a large repertoire of annexins and that the gene family has expanded separately across diplomonads, with members showing sequence diversity similar to that seen across kingdom-level groups such as plants and animals. S. salmonicida annexins are prominent components of the cytoskeleton and membrane. Two annexins are associated with a previously unrecognized structure in the anterior of the cell.

  20. Evolution, communication, observation from biology to membrane computing and back

    OpenAIRE

    2005-01-01

    La Computación Natural es una disciplina cuyo objetivo fundamental es la simulación e implementación de procesos dinámicos que se dan en la Naturaleza y que son susceptibles de ser interpretados como procedimientos de cálculo. ... height: 150%; font-family: 'Times New Roman','serif'; font-size: 12pt">La simulación que aborda la Computación Natural puede tener diversas interpretaciones a la hora de describir los nuevos modelos: que se utilice para el diseño de nuevos esquemas algorítmicos usan...

  1. Inferring biological evolution from fracture patterns in teeth.

    Science.gov (United States)

    Lawn, Brian R; Bush, Mark B; Barani, Amir; Constantino, Paul J; Wroe, Stephen

    2013-12-07

    It is hypothesised that specific tooth forms are adapted to resist fracture, in order to accommodate the high bite forces needed to secure, break down and consume food. Three distinct modes of tooth fracture are identified: longitudinal fracture, where cracks run vertically between the occlusal contact and the crown margin (or vice versa) within the enamel side wall; chipping fracture, where cracks run from near the edge of the occlusal surface to form a spall in the enamel at the side wall; and transverse fracture, where a crack runs horizontally through the entire section of the tooth to break off a fragment and expose the inner pulp. Explicit equations are presented expressing critical bite force for each fracture mode in terms of characteristic tooth dimensions. Distinctive transitions between modes occur depending on tooth form and size, and loading location and direction. Attention is focussed on the relatively flat, low-crowned molars of omnivorous mammals, including humans and other hominins and the elongate canines of living carnivores. At the same time, allusion to other tooth forms - the canines of the extinct sabre-tooth (Smilodon fatalis), the conical dentition of reptiles, and the columnar teeth of herbivores - is made to highlight the generality of the methodology. How these considerations impact on dietary behaviour in fossil and living taxa is discussed.

  2. Multiple changes in sialic acid biology during human evolution.

    Science.gov (United States)

    Varki, Ajit

    2009-04-01

    Humans are genetically very similar to "great apes", (chimpanzees, bonobos, gorillas and orangutans), our closest evolutionary relatives. We have discovered multiple genetic and biochemical differences between humans and these other hominids, in relation to sialic acids and in Siglecs (Sia-recognizing Ig superfamily lectins). An inactivating mutation in the CMAH gene eliminated human expression of N-glycolylneuraminic acid (Neu5Gc) a major sialic acid in "great apes". Additional human-specific changes have been found, affecting at least 10 of the dietary sources, particularly red meat and milk products. As humans also have varying and sometime high levels of circulating anti-Neu5Gc antibodies, there are implications for biotechnology products, and for some human diseases associated with chronic inflammation.

  3. Synthetic Biology: Engineering, Evolution and Design (SEED) Conference 2015

    Science.gov (United States)

    2015-12-01

    porter transgene that is stably integrated into a chromosome. Upon addition of doxycycline, the transgenic cells express a fusion protein that...sequences. In our study, ssOrigami structures with different sizes rang- ing from 1,000 to 4,000 nucleotides (nt) were assembled. Three diamond shape...also achieved. While the folding path is less obvious than simple diamond shapes, these complex ssOrigami struc- tures were also successfully assembled

  4. Natural History Education for Students Heading into the Century of Biology

    Science.gov (United States)

    McGlynn, Terrance P.

    2008-01-01

    Undergraduate biology students receive little training in natural history or in organismal biology. Natural history allows students to visualize mechanisms of evolution and identify common themes in the structure and function of organisms. By emphasizing natural history in all aspects of biology instruction, we might become closer to achieving the…

  5. The EvoDevoCI: A Concept Inventory for Gauging Students' Understanding of Evolutionary Developmental Biology

    Science.gov (United States)

    Perez, Kathryn E.; Hiatt, Anna; Davis, Gregory K.; Trujillo, Caleb; French, Donald P.; Terry, Mark; Price, Rebecca M.

    2013-01-01

    The American Association for the Advancement of Science 2011 report "Vision and Change in Undergraduate Biology Education" encourages the teaching of developmental biology as an important part of teaching evolution. Recently, however, we found that biology majors often lack the developmental knowledge needed to understand evolutionary…

  6. Evolution of colour vision in mammals.

    Science.gov (United States)

    Jacobs, Gerald H

    2009-10-12

    Colour vision allows animals to reliably distinguish differences in the distributions of spectral energies reaching the eye. Although not universal, a capacity for colour vision is sufficiently widespread across the animal kingdom to provide prima facie evidence of its importance as a tool for analysing and interpreting the visual environment. The basic biological mechanisms on which vertebrate colour vision ultimately rests, the cone opsin genes and the photopigments they specify, are highly conserved. Within that constraint, however, the utilization of these basic elements varies in striking ways in that they appear, disappear and emerge in altered form during the course of evolution. These changes, along with other alterations in the visual system, have led to profound variations in the nature and salience of colour vision among the vertebrates. This article concerns the evolution of colour vision among the mammals, viewing that process in the context of relevant biological mechanisms, of variations in mammalian colour vision, and of the utility of colour vision.

  7. Statistical Mechanics and Thermodynamics of Viral Evolution

    Science.gov (United States)

    Jones, Barbara; Kaufman, James

    Using methods drawn from physics we study the life cycle of viruses. We analyze a model of viral infection and evolution using the ``grand canonical ensemble'' and formalisms from statistical mechanics and thermodynamics. Using this approach we determine possible genetic states of a model virus and host as a function of two independent pressures-immune response and system temperature. We show the system has a real thermodynamic temperature, and discover a new phase transition between a positive temperature regime of normal replication and a negative temperature ``disordered'' phase of the virus. We distinguish this from previous observations of a phase transition that arises as a function of mutation rate. From an evolutionary biology point of view, at steady state the viruses naturally evolve to distinct quasispecies. The approach used here could be refined to apply to real biological systems, perhaps providing insight into immune escape, the emergence of novel pathogens and other results of viral evolution.

  8. Stochastic Physics, Complex Systems and Biology

    CERN Document Server

    Qian, Hong

    2012-01-01

    In complex systems, the interplay between nonlinear and stochastic dynamics gives rise to an evolution process in Darwinian sense with punctuated equilibrium, random "mutations" and "adaptations". The emergent discrete states in such a system, i.e., attractors, have natural robustness against both internal and external perturbations. Epigenetic states of a biological cell, a mesoscopic nonlinear stochastic open biochemical system, could be understood through such a framework.

  9. Rotating biological contactors: the Canadian experience

    Energy Technology Data Exchange (ETDEWEB)

    Cuenca, Manuel A. [Ryerson Polytechnical Univ., Toronto, ON (Canada). Chemical Engineering Dept.; Smith, Tom [CMS Rotordisk Inc., Concord, ON (Canada); Vianna, Arlinda C. [Servico Nacional de Aprendizagem Industrial (SENAI), Salvador, BA (Brazil)

    1993-12-31

    In fifteen years, Rotating Biological Contactors (RBC) have become one of the most attractive technologies for secondary wastewater treatment. The present work is a review of the evolution of RBC technology in the last twenty years. In addition, the status of the technology in Canada is described, emphasizing industrial facilities and landfill leachate treatment. An enumeration of the most relevant development areas is included. (author). 34 refs., 3 figs., 7 tabs.

  10. Biology of the Mangrove Palm, Nypa fruticans

    DEFF Research Database (Denmark)

    Barfod, Anders S.

    The Southeast Asian mangrove palm Nypa fruticans Wurmb occurs in large, monospecific stands in estuaries and along rivers. It is the only member of the subfamily Nypoideae, which derived early in palm evolution and is known from a fossil record extending back in time at least 70 millions years...... of the biology of Nypa fruticans and discuss its reproductive ecology from an evolutionary and management planning perspective....

  11. On the importance of evolution to developmental psychobiology.

    Science.gov (United States)

    Hill, W L

    1995-03-01

    The term developmental psychobiology implies an integration between psychology and biology. But what segment of biology does the discipline embrace? The present commentary asserts that developmental psychobiology devotes too much attention to structural biology, with its emphasis on proximate mechanisms, and fails to give enough prominence to evolutionary biology and ultimate perspectives. I have attempted to portray the significance of evolution to developmental psychobiology and to elaborate on how developmental psychobiology might contribute to refinements in evolutionary theory, especially recent modifications that advocate a greater role for developmental processes. Methodological suggestions are offered, which would broaden developmental psychobiology's perspective so that a more comprehensive analysis of behavioral development results.

  12. Patterns and Processes of Vertebrate Evolution

    Science.gov (United States)

    Carroll, Robert Lynn

    1997-04-01

    This new text provides an integrated view of the forces that influence the patterns and rates of vertebrate evolution from the level of living populations and species to those that resulted in the origin of the major vertebrate groups. The evolutionary roles of behavior, development, continental drift, and mass extinctions are compared with the importance of variation and natural selection that were emphasized by Darwin. It is extensively illustrated, showing major transitions between fish and amphibians, dinosaurs and birds, and land mammals to whales. No book since Simpson's Major Features of Evolution has attempted such a broad study of the patterns and forces of evolutionary change. Undergraduate students taking a general or advanced course on evolution, and graduate students and professionals in evolutionary biology and paleontology will find the book of great interest.

  13. OPEN PROBLEM: Some nonlinear challenges in biology

    Science.gov (United States)

    Mosconi, Francesco; Julou, Thomas; Desprat, Nicolas; Sinha, Deepak Kumar; Allemand, Jean-François; Croquette, Vincent; Bensimon, David

    2008-08-01

    Driven by a deluge of data, biology is undergoing a transition to a more quantitative science. Making sense of the data, building new models, asking the right questions and designing smart experiments to answer them are becoming ever more relevant. In this endeavour, nonlinear approaches can play a fundamental role. The biochemical reactions that underlie life are very often nonlinear. The functional features exhibited by biological systems at all levels (from the activity of an enzyme to the organization of a colony of ants, via the development of an organism or a functional module like the one responsible for chemotaxis in bacteria) are dynamically robust. They are often unaffected by order of magnitude variations in the dynamical parameters, in the number or concentrations of actors (molecules, cells, organisms) or external inputs (food, temperature, pH, etc). This type of structural robustness is also a common feature of nonlinear systems, exemplified by the fundamental role played by dynamical fixed points and attractors and by the use of generic equations (logistic map, Fisher-Kolmogorov equation, the Stefan problem, etc.) in the study of a plethora of nonlinear phenomena. However, biological systems differ from these examples in two important ways: the intrinsic stochasticity arising from the often very small number of actors and the role played by evolution. On an evolutionary time scale, nothing in biology is frozen. The systems observed today have evolved from solutions adopted in the past and they will have to adapt in response to future conditions. The evolvability of biological system uniquely characterizes them and is central to biology. As the great biologist T Dobzhansky once wrote: 'nothing in biology makes sense except in the light of evolution'.

  14. Fifty years of co-evolution and beyond: integrating co-evolution from molecules to species.

    Science.gov (United States)

    Carmona, Diego; Fitzpatrick, Connor R; Johnson, Marc T J

    2015-11-01

    Fifty years after Ehrlich and Raven's seminal paper, the idea of co-evolution continues to grow as a key concept in our understanding of organic evolution. This concept has not only provided a compelling synthesis between evolutionary biology and community ecology, but has also inspired research that extends beyond its original scope. In this article, we identify unresolved questions about the co-evolutionary process and advocate for the integration of co-evolutionary research from molecular to interspecific interactions. We address two basic questions: (i) What is co-evolution and how common is it? (ii) What is the unit of co-evolution? Both questions aim to explore the heart of the co-evolutionary process. Despite the claim that co-evolution is ubiquitous, we argue that there is in fact little evidence to support the view that reciprocal natural selection and coadaptation are common in nature. We also challenge the traditional view that co-evolution only occurs between traits of interacting species. Co-evolution has the potential to explain evolutionary processes and patterns that result from intra- and intermolecular biochemical interactions within cells, intergenomic interactions (e.g. nuclear-cytoplasmic) within species, as well as intergenomic interactions mediated by phenotypic traits between species. Research that bridges across these levels of organization will help to advance our understanding of the importance of the co-evolutionary processes in shaping the diversity of life on Earth.

  15. Punctualism, non-adaptationism, neutralism and evolution.

    Science.gov (United States)

    Volkenstein, M V

    1987-01-01

    In its further development the theory of evolution will incorporate molecular biology, synergetics and the theory of information. Using a simple model it is shown that speciation can be similar to phase transition. This is a thermodynamical statement which does not say anything concerning the sharpness and kinetic features of transition. Hence there is no contradiction between punctuated equilibrium and phyletic gradualism. The notion of punctualism can be used in the sense of phase transition. Evolution is directional because of constraints of natural selection due to the structure of organisms already existing and to the possible pathways of development. Correspondingly many characters are non-adaptative. Not only are the structures of proteins important for speciation but also the exact answers to the questions: "how much", "where" and "when"? These answers can be obtained as the results of regulation of genes, particularly of homeiotic regulation. The basis features of the structure of proteins are considered and the sense of the neutral theory is discussed in connection with degeneracy of correlation between the primary structure of a protein, its spatial structure and biological function. Informational aspects of evolution are discussed. Punctualism, non-adaptationism and neutralism form the triad of internally connected features of evolution. The Darwinian theory preserves its fundamental significance.

  16. 2007 Microbial Population Biology (July 22-26, 2007)

    Energy Technology Data Exchange (ETDEWEB)

    Anthony M. Dean

    2008-04-01

    Microbial Population Biology covers a diverse range of cutting edge issues in the microbial sciences and beyond. Firmly founded in evolutionary biology and with a strongly integrative approach, past meetings have covered topics ranging from the dynamics and genetics of adaptation to the evolution of mutation rate, community ecology, evolutionary genomics, altruism, and epidemiology. This meeting is never dull: some of the most significant and contentious issues in biology have been thrashed out here. We anticipate the 2007 meeting being no exception. The final form of the 2007 meeting is yet to be decided, but the following topics are likely to be included: evolutionary emergence of infectious disease and antibiotic resistance, genetic architecture and implications for the evolution of microbial populations, ageing in bacteria, biogeography, evolution of symbioses, the role of microbes in ecosystem function, and ecological genomics.

  17. Cosmic evolution: the context for astrobiology and its cultural implications

    Science.gov (United States)

    Dick, Steven J.

    2012-10-01

    Astrobiology must be seen in the context of cosmic evolution, the 13.7 billion-year master narrative of the universe. The idea of an evolving universe dates back only to the 19th century, and became a guiding principle for astronomical research only in the second half of the 20th century. The modern synthesis in evolutionary biology hastened the acceptance of the idea in its cosmic setting, as did the confirmation of the Big Bang theory for the origin of the universe. NASA programmes such as Origins incorporated it as a guiding principle. Cosmic evolution encompasses physical, biological and cultural evolution, and may result in a physical, biological or postbiological universe, each with its own implications for long-term human destiny, and each imbuing the meaning of life with different values. It has the status of an increasingly accepted worldview that is beginning to have a profound effect not only in science but also in religion and philosophy.

  18. Structural Approaches to Sequence Evolution Molecules, Networks, Populations

    CERN Document Server

    Bastolla, Ugo; Roman, H. Eduardo; Vendruscolo, Michele

    2007-01-01

    Structural requirements constrain the evolution of biological entities at all levels, from macromolecules to their networks, right up to populations of biological organisms. Classical models of molecular evolution, however, are focused at the level of the symbols - the biological sequence - rather than that of their resulting structure. Now recent advances in understanding the thermodynamics of macromolecules, the topological properties of gene networks, the organization and mutation capabilities of genomes, and the structure of populations make it possible to incorporate these key elements into a broader and deeply interdisciplinary view of molecular evolution. This book gives an account of such a new approach, through clear tutorial contributions by leading scientists specializing in the different fields involved.

  19. Resetting Biological Clocks

    Science.gov (United States)

    Winfree, Arthur T.

    1975-01-01

    Reports on experiments conducted on two biological clocks, in organisms in the plant and animal kingdoms, which indicate that biological oscillation can be arrested by a single stimulus of a definite strength delivered at the proper time. (GS)

  20. Biology is simple.

    Science.gov (United States)

    Newman, Tim

    2015-12-30

    This paper explores the potential for simplicity to reveal new biological understanding. Borrowing selectively from physics thinking, and contrasting with Crick's reductionist philosophy, the author argues that greater emphasis on simplicity is necessary to advance biology and its applications.

  1. Biology of Blood

    Science.gov (United States)

    ... here for the Professional Version Home Blood Disorders Biology of Blood Overview of Blood Resources In This ... Version. DOCTORS: Click here for the Professional Version Biology of Blood Overview of Blood Components of Blood ...

  2. Oxygen evolution reaction catalysis

    Science.gov (United States)

    Haber, Joel A.; Jin, Jian; Xiang, Chengxiang; Gregoire, John M.; Jones, Ryan J.; Guevarra, Dan W.; Shinde, Aniketa A.

    2016-09-06

    An Oxygen Evolution Reaction (OER) catalyst includes a metal oxide that includes oxygen, cerium, and one or more second metals. In some instances, the cerium is 10 to 80 molar % of the metals in the metal oxide and/or the catalyst includes two or more second metals. The OER catalyst can be included in or on an electrode. The electrode can be arranged in an oxygen evolution system such that the Oxygen Evolution Reaction occurs at the electrode.

  3. Synthetic biology: a challenge to mechanical explanations in biology?

    Science.gov (United States)

    Morange, Michel

    2012-01-01

    In their plans to modify organisms, synthetic biologists have contrasted engineering and tinkering. By drawing this contrast between their endeavors and what has happened during the evolution of organisms by natural selection, they underline the novelty of their projects and justify their ambitions. Synthetic biologists are at odds with a long tradition that has considered organisms as "perfect machines." This tradition had already been questioned by Stephen Jay Gould in the 1970s and received a major blow with the comparison made by François Jacob between organisms and the results of "bricolage" (tinkering). These contrasts between engineering and tinkering, synthetic biology and evolution, have no raison d'être. Machines built by humans are increasingly inspired by observations made on organisms. This is not a simple reversal of the previous trend-the mechanical conception of organisms-in which the characteristics of the latter were explained by comparison with human-built machines. Relations between organisms and machines have always been complex and ambiguous.

  4. The emphasis given to evolution in state science standards: A lever for change in evolution education?

    Science.gov (United States)

    Skoog, Gerald; Bilica, Kimberly

    2002-07-01

    This study analyzed the science frameworks of 49 states and the District of Colombia to determine the emphasis given to evolution in these documents at the middle and secondary levels. These concepts were species evolve over time, speciation, diversity of life, descent with modification from common ancestry, evidence of evolution, natural selection, pace and direction of evolution, and human evolution. Collectively, the 50 science frameworks emphasized evolution in a manner that suggests that if the public's support for standards-based curricula is a reality, the study of evolution will be emphasized in an unprecedented manner in the nation's schools in the near future. However, all concepts were not emphasized equally in these documents. For example, human evolution was included in only seven documents. The word evolution is absent from some standards. Despite these negatives, recent actions to improve existing standards or to adopt new standards that emphasize evolution have occurred. The metaphor lever of change is often used in the context of school reform. This metaphor suggests a simple system where one change can result in a desired outcome. However, in classrooms where curriculum decisions evolve constantly, multiple factors interact and reinforce one another in response to both internal and external contingencies that emerge. Educational change can not be reduced to a simple linear cause/effect situation. The change process involved is nonlinear where what goes in is not proportional to what comes out because of feedback loops and other factors that complicate results. This nonlinearity is reflected in the varied responses of teachers to specific contingencies. Yet, systems can be changed and nudged towards a structure where desired outcomes will emerge. Judicial rulings indicating that the teaching of evolution cannot be prohibited or equal time for creationism mandated, improved coverage of evolution in secondary school biology textbooks, the negative

  5. Museums teach evolution.

    Science.gov (United States)

    Diamond, Judy; Evans, E Margaret

    2007-06-01

    Natural history museums play a significant role in educating the general public about evolution. This article describes Explore Evolution, one of the largest evolution education projects funded by the National Science Foundation. A group of regional museums from the Midwestern United States worked with leading evolutionary scientists to create multiple permanent exhibit galleries and a curriculum book for youth. This program invites the public to experience current evolutionary research on organisms that range in size from HIV to whales. Learning research is being conducted on museum visitors to understand how they reason about evolution and to determine what influences the process of conceptual change.

  6. Designing synthetic biology.

    Science.gov (United States)

    Agapakis, Christina M

    2014-03-21

    Synthetic biology is frequently defined as the application of engineering design principles to biology. Such principles are intended to streamline the practice of biological engineering, to shorten the time required to design, build, and test synthetic gene networks. This streamlining of iterative design cycles can facilitate the future construction of biological systems for a range of applications in the production of fuels, foods, materials, and medicines. The promise of these potential applications as well as the emphasis on design has prompted critical reflection on synthetic biology from design theorists and practicing designers from many fields, who can bring valuable perspectives to the discipline. While interdisciplinary connections between biologists and engineers have built synthetic biology via the science and the technology of biology, interdisciplinary collaboration with artists, designers, and social theorists can provide insight on the connections between technology and society. Such collaborations can open up new avenues and new principles for research and design, as well as shed new light on the challenging context-dependence-both biological and social-that face living technologies at many scales. This review is inspired by the session titled "Design and Synthetic Biology: Connecting People and Technology" at Synthetic Biology 6.0 and covers a range of literature on design practice in synthetic biology and beyond. Critical engagement with how design is used to shape the discipline opens up new possibilities for how we might design the future of synthetic biology.

  7. BIOLOGICAL FOUNDATIONS OF LANGUAGE.

    Science.gov (United States)

    LENNEBERG, ERIC H.

    THE RELATIONSHIP BETWEEN BIOLOGY AND LANGUAGE IS EXPLORED IN THIS VOLUME. THE AUTHOR BELIEVES THAT "LANGUAGE IS THE MANIFESTATION OF SPECIES-SPECIFIC COGNITIVE PROPENSITIES. IT IS THE CONSEQUENCE OF THE BIOLOGICAL PECULIARITIES THAT MAKE A HUMAN TYPE OF COGNITION POSSIBLE." IN ATTEMPTING TO "REINSTATE THE CONCEPT OF THE BIOLOGICAL BASIS OF…

  8. Biology Myth-Killers

    Science.gov (United States)

    Lampert, Evan

    2014-01-01

    "Biology Myth-Killers" is an activity designed to identify and correct common misconceptions for high school and college introductory biology courses. Students identify common myths, which double as biology misconceptions, and use appropriate sources to share the "truth" about the myths. This learner-centered activity is a fun…

  9. Shaping Robust System through Evolution

    CERN Document Server

    Kaneko, Kunihiko

    2008-01-01

    Biological functions are generated as a result of developmental dynamics that form phenotypes governed by genotypes. The dynamical system for development is shaped through genetic evolution following natural selection based on the fitness of the phenotype. Here we study how this dynamical system is robust to noise during development and to genetic change by mutation. We adopt a simplified transcription regulation network model to govern gene expression, which gives a fitness function. Through simulations of the network that undergoes mutation and selection, we show that a certain level of noise in gene expression is required for the network to acquire both types of robustness. The results reveal how the noise that cells encounter during development shapes any network's robustness, not only to noise but also to mutations. We also establish a relationship between developmental and mutational robustness through phenotypic variances caused by genetic variation and epigenetic noise. A universal relationship betwee...

  10. CADEE: Computer-Aided Directed Evolution of Enzymes

    Science.gov (United States)

    Amrein, Beat Anton; Steffen-Munsberg, Fabian; Szeler, Ireneusz; Purg, Miha; Kamerlin, Shina Caroline Lynn

    2017-01-01

    The tremendous interest in enzymes as biocatalysts has led to extensive work in enzyme engineering, as well as associated methodology development. Here, a new framework for computer-aided directed evolution of enzymes (CADEE) is presented which allows a drastic reduction in the time necessary to prepare and analyze in silico semi-automated directed evolution of enzymes. A pedagogical example of the application of CADEE to a real biological system is also presented in order to illustrate the CADEE workflow. PMID:28250941

  11. Evolutionary perspectives into placental biology and disease

    Directory of Open Access Journals (Sweden)

    Edward B. Chuong

    2013-12-01

    Full Text Available In all mammals including humans, development takes place within the protective environment of the maternal womb. Throughout gestation, nutrients and waste products are continuously exchanged between mother and fetus through the placenta. Despite the clear importance of the placenta to successful pregnancy and the health of both mother and offspring, relatively little is understood about the biology of the placenta and its role in pregnancy-related diseases. Given that pre- and peri-natal diseases involving the placenta affect millions of women and their newborns worldwide, there is an urgent need to understand placenta biology and development. Here, we suggest that the placenta is an organ under unique selective pressures that have driven its rapid diversification throughout mammalian evolution. The high divergence of the placenta complicates the use of non-human animal models and necessitates an evolutionary perspective when studying its biology and role in disease. We suggest that diversifying evolution of the placenta is primarily driven by intraspecies evolutionary conflict between mother and fetus, and that many pregnancy diseases are a consequence of this evolutionary force. Understanding how maternal–fetal conflict shapes both basic placental and reproductive biology – in all species – will provide key insights into diseases of pregnancy.

  12. Culture shapes the evolution of cognition.

    Science.gov (United States)

    Thompson, Bill; Kirby, Simon; Smith, Kenny

    2016-04-19

    A central debate in cognitive science concerns the nativist hypothesis, the proposal that universal features of behavior reflect a biologically determined cognitive substrate: For example, linguistic nativism proposes a domain-specific faculty of language that strongly constrains which languages can be learned. An evolutionary stance appears to provide support for linguistic nativism, because coordinated constraints on variation may facilitate communication and therefore be adaptive. However, language, like many other human behaviors, is underpinned by social learning and cultural transmission alongside biological evolution. We set out two models of these interactions, which show how culture can facilitate rapid biological adaptation yet rule out strong nativization. The amplifying effects of culture can allow weak cognitive biases to have significant population-level consequences, radically increasing the evolvability of weak, defeasible inductive biases; however, the emergence of a strong cultural universal does not imply, nor lead to, nor require, strong innate constraints. From this we must conclude, on evolutionary grounds, that the strong nativist hypothesis for language is false. More generally, because such reciprocal interactions between cultural and biological evolution are not limited to language, nativist explanations for many behaviors should be reconsidered: Evolutionary reasoning shows how we can have cognitively driven behavioral universals and yet extreme plasticity at the level of the individual-if, and only if, we account for the human capacity to transmit knowledge culturally. Wherever culture is involved, weak cognitive biases rather than strong innate constraints should be the default assumption.

  13. The use of information theory in evolutionary biology.

    Science.gov (United States)

    Adami, Christoph

    2012-05-01

    Information is a key concept in evolutionary biology. Information stored in a biological organism's genome is used to generate the organism and to maintain and control it. Information is also that which evolves. When a population adapts to a local environment, information about this environment is fixed in a representative genome. However, when an environment changes, information can be lost. At the same time, information is processed by animal brains to survive in complex environments, and the capacity for information processing also evolves. Here, I review applications of information theory to the evolution of proteins and to the evolution of information processing in simulated agents that adapt to perform a complex task.

  14. Positive feelings in learning and interest development in biology education

    DEFF Research Database (Denmark)

    Petersen, Morten Rask; Dohn, Niels Bonderup

    2015-01-01

    that students who changed conceptual understanding in the tests also experienced deeper learning and understanding of natural selection and evolution. These students also experience positive feelings towards learning and learning can enhance their interest in evolution and biology in general. These findings...... for learning (e.g. Krapp, 2002). Here we turn the interplay and see learning as a facilitator for interest development. This interplay was studied in upper secondary biology education. Student’s conducted an exercise on modelling natural selection with LEGO® bricks (Christensen-Dalsgaard & Kanneworf, 2009...

  15. A Mixed Exam Format Closes the Gap for Students with a Conflict between Their Religious Belief & the Theory of Evolution

    Science.gov (United States)

    Stanger-Hall, Kathrin F.; Wenner, Julianne A.

    2014-01-01

    We assessed the performance of students with a self-reported conflict between their religious belief and the theory of evolution in two sections of a large introductory biology course (N = 373 students). Student performance was measured through pretest and posttest evolution essays and multiple- choice (MC) questions (evolution-related and…

  16. The concept of mechanism in biology.

    Science.gov (United States)

    Nicholson, Daniel J

    2012-03-01

    The concept of mechanism in biology has three distinct meanings. It may refer to a philosophical thesis about the nature of life and biology ('mechanicism'), to the internal workings of a machine-like structure ('machine mechanism'), or to the causal explanation of a particular phenomenon ('causal mechanism'). In this paper I trace the conceptual evolution of 'mechanism' in the history of biology, and I examine how the three meanings of this term have come to be featured in the philosophy of biology, situating the new 'mechanismic program' in this context. I argue that the leading advocates of the mechanismic program (i.e., Craver, Darden, Bechtel, etc.) inadvertently conflate the different senses of 'mechanism'. Specifically, they all inappropriately endow causal mechanisms with the ontic status of machine mechanisms, and this invariably results in problematic accounts of the role played by mechanism-talk in scientific practice. I suggest that for effective analyses of the concept of mechanism, causal mechanisms need to be distinguished from machine mechanisms, and the new mechanismic program in the philosophy of biology needs to be demarcated from the traditional concerns of mechanistic biology.

  17. The mystery of language evolution

    Science.gov (United States)

    Hauser, Marc D.; Yang, Charles; Berwick, Robert C.; Tattersall, Ian; Ryan, Michael J.; Watumull, Jeffrey; Chomsky, Noam; Lewontin, Richard C.

    2014-01-01

    Understanding the evolution of language requires evidence regarding origins and processes that led to change. In the last 40 years, there has been an explosion of research on this problem as well as a sense that considerable progress has been made. We argue instead that the richness of ideas is accompanied by a poverty of evidence, with essentially no explanation of how and why our linguistic computations and representations evolved. We show that, to date, (1) studies of nonhuman animals provide virtually no relevant parallels to human linguistic communication, and none to the underlying biological capacity; (2) the fossil and archaeological evidence does not inform our understanding of the computations and representations of our earliest ancestors, leaving details of origins and selective pressure unresolved; (3) our understanding of the genetics of language is so impoverished that there is little hope of connecting genes to linguistic processes any time soon; (4) all modeling attempts have made unfounded assumptions, and have provided no empirical tests, thus leaving any insights into language's origins unverifiable. Based on the current state of evidence, we submit that the most fundamental questions about the origins and evolution of our linguistic capacity remain as mysterious as ever, with considerable uncertainty about the discovery of either relevant or conclusive evidence that can adjudicate among the many open hypotheses. We conclude by presenting some suggestions about possible paths forward. PMID:24847300

  18. The mystery of language evolution

    Directory of Open Access Journals (Sweden)

    Marc D Hauser

    2014-05-01

    Full Text Available Understanding the evolution of language requires evidence regarding origins and processes that led to change. In the last 40 years, there has been an explosion of research on this problem as well as a sense that considerable progress has been made. We argue instead that the richness of ideas is accompanied by a poverty of evidence, with essentially no explanation of how and why our linguistic computations and representations evolved. We show that, to date, 1 studies of nonhuman animals provide virtually no relevant parallels to human linguistic communication, and none to the underlying biological capacity; 2 the fossil and archaeological evidence does not inform our understanding of the computations and representations of our earliest ancestors, leaving details of origins and selective pressure unresolved; 3 our understanding of the genetics of language is so impoverished that there is little hope of connecting genes to linguistic processes any time soon; 4 all modeling attempts have made unfounded assumptions, and have provided no empirical tests, thus leaving any insights into language’s origins unverifiable. Based on the current state of evidence, we submit that the most fundamental questions about the origins and evolution of our linguistic capacity remain as mysterious as ever, with considerable uncertainty about the discovery of either relevant or conclusive evidence that can adjudicate among the many open hypotheses. We conclude by presenting some suggestions about possible paths forward.

  19. Evolution is only a theory?

    Science.gov (United States)

    Peshkin, Murray

    2008-04-01

    I have been speaking to diverse groups about science and religion in the context of the attacks on the teaching of biological evolution in public schools. My audiences have included church groups, classrooms, business clubs, and general public. In explaining why science does not threaten most people's religious beliefs and why belief in evolution is not really optional, I have learned that most people have never been told what a theory is and how we know when it's right, or what it means that our theories are always provisional but well-established theories are nevertheless reliable where they apply. It seems that we have taught students and the public about gravity and DNA, but never told them what science is all about. We need to do better. The people I have addressed have mostly appreciated hearing about these things and about why science, properly understood, does not deny most people's religious beliefs. I will discuss these and other lessons I have learned from the reactions to my talks. *For identification. This work is not supported by Argonne Natl. Lab.

  20. The mystery of language evolution.

    Science.gov (United States)

    Hauser, Marc D; Yang, Charles; Berwick, Robert C; Tattersall, Ian; Ryan, Michael J; Watumull, Jeffrey; Chomsky, Noam; Lewontin, Richard C

    2014-01-01

    Understanding the evolution of language requires evidence regarding origins and processes that led to change. In the last 40 years, there has been an explosion of research on this problem as well as a sense that considerable progress has been made. We argue instead that the richness of ideas is accompanied by a poverty of evidence, with essentially no explanation of how and why our linguistic computations and representations evolved. We show that, to date, (1) studies of nonhuman animals provide virtually no relevant parallels to human linguistic communication, and none to the underlying biological capacity; (2) the fossil and archaeological evidence does not inform our understanding of the computations and representations of our earliest ancestors, leaving details of origins and selective pressure unresolved; (3) our understanding of the genetics of language is so impoverished that there is little hope of connecting genes to linguistic processes any time soon; (4) all modeling attempts have made unfounded assumptions, and have provided no empirical tests, thus leaving any insights into language's origins unverifiable. Based on the current state of evidence, we submit that the most fundamental questions about the origins and evolution of our linguistic capacity remain as mysterious as ever, with considerable uncertainty about the discovery of either relevant or conclusive evidence that can adjudicate among the many open hypotheses. We conclude by presenting some suggestions about possible paths forward.

  1. Sisyphean evolution in Darwin's finches.

    Science.gov (United States)

    McKay, Bailey D; Zink, Robert M

    2015-08-01

    The trajectory of speciation involves geographic isolation of ancestral populations followed by divergence by natural selection, genetic drift or sexual selection. Once started, the process may experience fits and starts, as sometimes diverging populations intermittently reconnect. In theory populations might cycle between stages of differentiation and never attain species status, a process we refer to as Sisyphean evolution. We argue that the six putative ground finch species (genus Geospiza) of the Galápagos Islands represent a dramatic example of Sisyphean evolution that has been confused with the standard model of speciation. The dynamic environment of the Galápagos, closely spaced islands, and frequent dispersal and introgression have prevented the completion of the speciation process. We suggest that morphological clusters represent locally adapted ecomorphs, which might mimic, and have been confused with, species, but these ecomorphs do not form separate gene pools and are ephemeral in space and time. Thus the pattern of morphological, behavioural and genetic variation supports recognition of a single species of Geospiza, which we suggest should be recognized as Darwin's ground finch (Geospiza magnirostris). We argue that instead of providing an icon of insular speciation and adaptive radiation, which is featured in nearly every textbook on evolutionary biology, Darwin's ground finch represents a potentially more interesting phenomenon, one of transient morphs trapped in an unpredictable cycle of Sisyphean evolution. Instead of revealing details of the origin of species, the mechanisms underlying the transient occurrence of ecomorphs provide one of the best illustrations of the antagonistic effects of natural selection and introgression.

  2. Woese on the received view of evolution.

    Science.gov (United States)

    Sarkar, Sahotra

    2014-01-01

    As part of his attempt to reconstruct the earliest phase of the evolution of life on Earth, Woese produced a compelling critique of the received view of evolution from the 20th century. This paper explicitly articulates two related features of that critique that are fundamental but the first of which has not been sufficiently clearly recognized in the context of evolutionary theorizing: (1) according to Woese's scenario of communal evolution during life's earliest phase (roughly, the first billion years of life on Earth), well-defined biological individuals (and, thus, individual lineages) did not exist; and (2) during that phase, evolutionary change took place through ubiquitous horizontal gene transfer (HGT) rather than through vertical transmission of features (including genes) and the combinatorics of HGT was the dominant mechanism of evolutionary change. Both factors present serious challenges to the received view of evolution and that framework would have to be radically altered to incorporate these factors. The extent to which this will be necessary will depend on whether Woese's scenario of collective early evolution is correct.

  3. New thinking: the evolution of human cognition.

    Science.gov (United States)

    Heyes, Cecilia

    2012-08-05

    Humans are animals that specialize in thinking and knowing, and our extraordinary cognitive abilities have transformed every aspect of our lives. In contrast to our chimpanzee cousins and Stone Age ancestors, we are complex political, economic, scientific and artistic creatures, living in a vast range of habitats, many of which are our own creation. Research on the evolution of human cognition asks what types of thinking make us such peculiar animals, and how they have been generated by evolutionary processes. New research in this field looks deeper into the evolutionary history of human cognition, and adopts a more multi-disciplinary approach than earlier 'Evolutionary Psychology'. It is informed by comparisons between humans and a range of primate and non-primate species, and integrates findings from anthropology, archaeology, economics, evolutionary biology, neuroscience, philosophy and psychology. Using these methods, recent research reveals profound commonalities, as well striking differences, between human and non-human minds, and suggests that the evolution of human cognition has been much more gradual and incremental than previously assumed. It accords crucial roles to cultural evolution, techno-social co-evolution and gene-culture co-evolution. These have produced domain-general developmental processes with extraordinary power-power that makes human cognition, and human lives, unique.

  4. Toward an integration of evolutionary biology and ecosystem science.

    Science.gov (United States)

    Matthews, Blake; Narwani, Anita; Hausch, Stephen; Nonaka, Etsuko; Peter, Hannes; Yamamichi, Masato; Sullam, Karen E; Bird, Kali C; Thomas, Mridul K; Hanley, Torrance C; Turner, Caroline B

    2011-07-01

    At present, the disciplines of evolutionary biology and ecosystem science are weakly integrated. As a result, we have a poor understanding of how the ecological and evolutionary processes that create, maintain, and change biological diversity affect the flux of energy and materials in global biogeochemical cycles. The goal of this article was to review several research fields at the interfaces between ecosystem science, community ecology and evolutionary biology, and suggest new ways to integrate evolutionary biology and ecosystem science. In particular, we focus on how phenotypic evolution by natural selection can influence ecosystem functions by affecting processes at the environmental, population and community scale of ecosystem organization. We develop an eco-evolutionary model to illustrate linkages between evolutionary change (e.g. phenotypic evolution of producer), ecological interactions (e.g. consumer grazing) and ecosystem processes (e.g. nutrient cycling). We conclude by proposing experiments to test the ecosystem consequences of evolutionary changes.

  5. The Effect of Contextual Material on Evolution in the Jordanian Secondary-School Curriculum on Students' Acceptance of the Theory of Evolution

    Science.gov (United States)

    De Baz, Theodora; El-Weher, Mahmoud

    2012-01-01

    The purpose of this study was to detect the extent to which contextual material of a unit on "The origin and evolution of living organisms" included in the high-school biology curriculum in Jordan affected students' acceptance of the theory of evolution. The participants of this study consisted of 107 tenth-grade students randomly drawn…

  6. The Effect of Contextual Material on Evolution in the Jordanian Secondary-School Curriculum on Students' Acceptance of the Theory of Evolution

    Science.gov (United States)

    De Baz, Theodora; El-Weher, Mahmoud

    2012-01-01

    The purpose of this study was to detect the extent to which contextual material of a unit on "The origin and evolution of living organisms" included in the high-school biology curriculum in Jordan affected students' acceptance of the theory of evolution. The participants of this study consisted of 107 tenth-grade students randomly drawn from three…

  7. On the emergence of biology from chemistry: a discontinuist perspective from the point of view of stability and regulation.

    Science.gov (United States)

    Bich, Leonardo; Damiano, Luisa

    2012-10-01

    In this paper we argue that molecular evolution, and the evolution of prebiotic and early biological systems are qualitatively different processes, in which a crucial role is played respectively by structural stability and by dynamical mechanisms of regulation and integration. These different features entail also distinct modalities of interaction between system and environment that need to be taken into consideration when discussing molecular and biological evolution and selection.

  8. Computational systems chemical biology.

    Science.gov (United States)

    Oprea, Tudor I; May, Elebeoba E; Leitão, Andrei; Tropsha, Alexander

    2011-01-01

    There is a critical need for improving the level of chemistry awareness in systems biology. The data and information related to modulation of genes and proteins by small molecules continue to accumulate at the same time as simulation tools in systems biology and whole body physiologically based pharmacokinetics (PBPK) continue to evolve. We called this emerging area at the interface between chemical biology and systems biology systems chemical biology (SCB) (Nat Chem Biol 3: 447-450, 2007).The overarching goal of computational SCB is to develop tools for integrated chemical-biological data acquisition, filtering and processing, by taking into account relevant information related to interactions between proteins and small molecules, possible metabolic transformations of small molecules, as well as associated information related to genes, networks, small molecules, and, where applicable, mutants and variants of those proteins. There is yet an unmet need to develop an integrated in silico pharmacology/systems biology continuum that embeds drug-target-clinical outcome (DTCO) triplets, a capability that is vital to the future of chemical biology, pharmacology, and systems biology. Through the development of the SCB approach, scientists will be able to start addressing, in an integrated simulation environment, questions that make the best use of our ever-growing chemical and biological data repositories at the system-wide level. This chapter reviews some of the major research concepts and describes key components that constitute the emerging area of computational systems chemical biology.

  9. Evolution for Young Victorians

    Science.gov (United States)

    Lightman, Bernard

    2012-01-01

    Evolution was a difficult topic to tackle when writing books for the young in the wake of the controversies over Darwin's "Origin of Species." Authors who wrote about evolution for the young experimented with different ways of making the complex concepts of evolutionary theory accessible and less controversial. Many authors depicted presented…

  10. Software evolution with XVCL

    DEFF Research Database (Denmark)

    Zhang, Weishan; Jarzabek, Stan; Zhang, Hongyu

    2004-01-01

    This chapter introduces software evolution with XVCL (XML-based Variant Configuration Language), which is an XML-based metaprogramming technique. As the software evolves, a large number of variants may arise, especially whtn such kinds of evolutions are related to multiple platforms as shown in o...

  11. Hydrogen evolution reaction catalyst

    Science.gov (United States)

    Subbaraman, Ram; Stamenkovic, Vojislav; Markovic, Nenad; Tripkovic, Dusan

    2016-02-09

    Systems and methods for a hydrogen evolution reaction catalyst are provided. Electrode material includes a plurality of clusters. The electrode exhibits bifunctionality with respect to the hydrogen evolution reaction. The electrode with clusters exhibits improved performance with respect to the intrinsic material of the electrode absent the clusters.

  12. Kognition, evolution og Bibel

    DEFF Research Database (Denmark)

    Jensen, Hans Jørgen Lundager

    2012-01-01

    En opfordring til, at Bibelvidneskaberne oprienterer sig i retning af aktuelle teorier om bio-kulturel evolution (Merlin Donald, aksetids-teori hos fx Robert Bellah)......En opfordring til, at Bibelvidneskaberne oprienterer sig i retning af aktuelle teorier om bio-kulturel evolution (Merlin Donald, aksetids-teori hos fx Robert Bellah)...

  13. Self and Evolution.

    Science.gov (United States)

    Csikszentmihalyi, Mihaly

    1998-01-01

    Suggests the time has come for humans to direct their own individual evolution and the evolution of the entire species. Argues that ways must be found to encourage individuals, families, and cultures to discover and develop their differentiating characteristics and help these groups integrate with other cultures, customs, and belief systems.…

  14. Evolution of Constructivism

    Science.gov (United States)

    Liu, Chu Chih; Chen, I Ju

    2010-01-01

    The contrast between social constructivism and cognitive constructivism are depicted in different ways in many studies. The purpose of this paper is to summarize the evolution of constructivism and put a focus on social constructivism from the perception of Vygotsky. This study provides a general idea of the evolution of constructivism for people…

  15. Biological modulation of tectonics

    Science.gov (United States)

    Sleep, N. H.; Bird, D. K.

    2008-12-01

    Photosynthesis has had geologic consequences over the Earth's history. In addition to modifying Earth's atmosphere and ocean chemistry, it has also modulated tectonic processes through enhanced weathering and modification of the nature and composition of sedimentary rocks within fold mountain belts and convergent margins. Molecular biological studies indicate that bacterial photosynthesis evolved just once and that most bacterial clades descend from this photosynthetic common ancestor. Iron-based photosynthesis (ideally 4FeO + CO2 + H2O = 2Fe2O3 + CH2O) was the most bountiful anoxygenic niche on land. The back reaction provided energy to heterotrophic microbes and returned FeO to the photosynthetic microbes. Bacterial land colonists evolved into ecosystems that effectively weathered FeO-bearing minerals and volcanic glass. Clays, sands, and dissolved cations from the weathering process entered the ocean and formed our familiar classes sedimentary rocks: shales, sandstones, and carbonates. Marine photosynthesis caused organic carbon to accumulate in black shales. In contrast, non-photosynthetic ecosystems do not cause organic carbon to accumulate in shale. These evolutionary events occurred before 3.8 Ga as black shales are among the oldest rock types (Rosing and Frei, Earth Planet. Sci. Lett. 217, 237-244, 2004). Thick sedimentary sequences deformed into fold mountain belts. They remelted at depth to form granitic rocks (Rosing et al., Palaeoclimatol. Palaeoecol. 232, 99-11, 2006). Regions of outcropping low-FeO rocks including granites, quartzites, and some shales were a direct result. This dearth of FeO favored the evolution of oxic photosynthesis of cyanobacteria from photosynthetic soil bacteria. Black shales have an additional modulation effect on tectonics as they concentrate radioactive elements, particularly uranium (e.g. so that the surface heat flow varies by a factor of ca. 2). Thick sequences of black shales at continental rises of passive margins are

  16. Synthetic biology analysed tools for discussion and evaluation

    CERN Document Server

    2016-01-01

    Synthetic biology is a dynamic, young, ambitious, attractive, and heterogeneous scientific discipline. It is constantly developing and changing, which makes societal evaluation of this emerging new science a challenging task, prone to misunderstandings. Synthetic biology is difficult to capture, and confusion arises not only regarding which part of synthetic biology the discussion is about, but also with respect to the underlying concepts in use. This book offers a useful toolbox to approach this complex and fragmented field. It provides a biological access to the discussion using a 'layer' model that describes the connectivity of synthetic or semisynthetic organisms and cells to the realm of natural organisms derived by evolution. Instead of directly reviewing the field as a whole, firstly our book addresses the characteristic features of synthetic biology that are relevant to the societal discussion. Some of these features apply only to parts of synthetic biology, whereas others are relevant to synthetic bi...

  17. Power Laws, Scale-Free Networks and Genome Biology

    CERN Document Server

    Koonin, Eugene V; Karev, Georgy P

    2006-01-01

    Power Laws, Scale-free Networks and Genome Biology deals with crucial aspects of the theoretical foundations of systems biology, namely power law distributions and scale-free networks which have emerged as the hallmarks of biological organization in the post-genomic era. The chapters in the book not only describe the interesting mathematical properties of biological networks but moves beyond phenomenology, toward models of evolution capable of explaining the emergence of these features. The collection of chapters, contributed by both physicists and biologists, strives to address the problems in this field in a rigorous but not excessively mathematical manner and to represent different viewpoints, which is crucial in this emerging discipline. Each chapter includes, in addition to technical descriptions of properties of biological networks and evolutionary models, a more general and accessible introduction to the respective problems. Most chapters emphasize the potential of theoretical systems biology for disco...

  18. First molecules, biological chirality, origin(s) of life.

    Science.gov (United States)

    Caglioti, Luciano; Micskei, Károly; Pályi, Gyula

    2011-01-01

    Origin(s) of biological chirality appear(s) to be intimately connected to origin(s) of life. Prebiotic evolution toward these important turning points can be traced back to single chiral molecules. These can be small (monomeric) units as amino acids or monosaccharides or oligomers as oligo-RNA type molecules. Earlier speculations about these two kinds of entries to biological chirality are critically reviewed.

  19. A holistic approach to marine eco-systems biology.

    OpenAIRE

    Eric Karsenti; Acinas, Silvia G.; Peer Bork; Chris Bowler; Colomban De Vargas; Jeroen Raes; Matthew Sullivan; Detlev Arendt; Francesca Benzoni; Jean-Michel Claverie; Mick Follows; Gaby Gorsky; Pascal Hingamp; Daniele Iudicone; Olivier Jaillon

    2011-01-01

    With biology becoming quantitative, systems-level studies can now be performed at spatial scales ranging from molecules to ecosystems. Biological data generated consistently across scales can be integrated with physico-chemical contextual data for a truly holistic approach, with a profound impact on our understanding of life [1]–[5]. Marine ecosystems are crucial in the regulation of Earth's biogeochemical cycles and climate [6],[7]. Yet their organization, evolution, and dynamics remain poor...

  20. Towards developing algal synthetic biology.

    Science.gov (United States)

    Scaife, Mark Aden; Smith, Alison Gail

    2016-06-15

    The genetic, physiological and metabolic diversity of microalgae has driven fundamental research into photosynthesis, flagella structure and function, and eukaryotic evolution. Within the last 10 years these organisms have also been investigated as potential biotechnology platforms, for example to produce high value compounds such as long chain polyunsaturated fatty acids, pigments and antioxidants, and for biodiesel precursors, in particular triacylglycerols (TAGs). Transformation protocols, molecular tools and genome sequences are available for a number of model species including the green alga Chlamydomonas reinhardtii and the diatom Phaeodactylum tricornutum, although for both species there are bottlenecks to be overcome to allow rapid and predictable genetic manipulation. One approach to do this would be to apply the principles of synthetic biology to microalgae, namely the cycle of Design-Build-Test, which requires more robust, predictable and high throughput methods. In this mini-review we highlight recent progress in the areas of improving transgene expression, genome editing, identification and design of standard genetic elements (parts), and the use of microfluidics to increase throughput. We suggest that combining these approaches will provide the means to establish algal synthetic biology, and that application of standard parts and workflows will avoid parallel development and capitalize on lessons learned from other systems.