Quattrochi, Dale A.; Arnold, James E. (Technical Monitor)
As a field of study, biogeography may be considered a bricolage - it has been constructed from many different facets from an array of research disciplines including biology, botany, zoology, geography, and geology. Biogeography focuses on the study of the constantly changing ranges of plants and animals, over multitude of space and time scales. It also includes the study of the structure and dynamics of biotic communities and ecosystems as they relate to both natural and anthropogenic processes. As it exists today, biogeography is an interdisciplinary research area founded in both the biological and Earth sciences. From a purely biological perspective, biogeography may be perceived as one of two types of studies: 1. biotic distributions and broad scales, and interpretations of the evolutionary and dispersal history of a single taxon or a few taxa; or 2. biotic distributions at local-to-regional scales, and interpretations of these distributions in relation to contemporary environments and rates of immigration or extinction. The first type of study is what is most usually associated with the term "biogeography" as disciplinary research field. It is conventionally termed "classical biogeography" because it reflects the continuity of research foci on which biogeography was founded in the nineteenth-century. The second type of biogeographical study has more modern day roots and is termed "geographical ecology" to reflect the theoretical predilections of ecologists and population biologists. Geographical ecology for all intents has become merged with ecology and exists as a sub discipline within this larger field of study.
Spellerberg, Ian F.; Sawyer, John W. D.
Biogeography is about the geographical distribution, both past and present, of plants, animals and other organisms. In this undergraduate textbook, Spellerberg and Sawyer bring a modern approach to a developing subject, writing in a lively and sometimes provocative manner. Throughout the text, the authors emphasize the applications of biogeography to conservation management, economic production, environmental assessment, sustainable use of resources, landscape planning, and public health. They discuss applications of island biogeography in conservation, the concept of wildlife corridors, the analysis of biogeographical data, and the role of humans and their cultures in biogeography. The applied approach of this textbook, along with its numerous illustrative examples and figures, make it a unique introduction to the field for many geography, biology and environmental science students.
David A. Hooper
Full Text Available Review of The Great Cacti: Ethnobotany & Biogeography. David Yetman. 2007. The University of Arizona, Tucson. Pp. 320, 366 color photographs, 17 maps. $59.95 (cloth. ISBN 9780816524310.
Stacy, Apollo; McNally, Luke; Darch, Sophie E; Brown, Sam P; Whiteley, Marvin
Microbial communities are spatially organized in both the environment and the human body. Although patterns exhibited by these communities are described by microbial biogeography, this discipline has previously only considered large-scale, global patterns. By contrast, the fine-scale positioning of a pathogen within an infection site can greatly alter its virulence potential. In this Review, we highlight the importance of considering spatial positioning in the study of polymicrobial infections and discuss targeting biogeography as a therapeutic strategy. PMID:26714431
Panchal, V K; Kaur, Navdeep; Kundra, Harish
Biogeography is the study of the geographical distribution of biological organisms. The mindset of the engineer is that we can learn from nature. Biogeography Based Optimization is a burgeoning nature inspired technique to find the optimal solution of the problem. Satellite image classification is an important task because it is the only way we can know about the land cover map of inaccessible areas. Though satellite images have been classified in past by using various techniques, the researchers are always finding alternative strategies for satellite image classification so that they may be prepared to select the most appropriate technique for the feature extraction task in hand. This paper is focused on classification of the satellite image of a particular land cover using the theory of Biogeography based Optimization. The original BBO algorithm does not have the inbuilt property of clustering which is required during image classification. Hence modifications have been proposed to the original algorithm and...
Dawson, Michael; Algar, Adam; Antonelli, Alexandre;
The opportunity to reflect broadly on the accomplishments, prospects, and reach of a field may present itself relatively infrequently. Each biennial meeting of the International Biogeography Society showcases ideas solicited and developed largely during the preceding year, by individuals or teams...... from across the breadth of the discipline. Here, we highlight challenges, developments, and opportunities in biogeography from that biennial synthesis. We note the realized and potential impact of rapid data accumulation in several fields, a renaissance for inter‐disciplinary research, the importance...... hypothetico‐deductive branches and establish a greater role within and outside academia....
Helmus, Matthew R; Mahler, D Luke; Losos, Jonathan B
For centuries, biogeographers have examined the factors that produce patterns of biodiversity across regions. The study of islands has proved particularly fruitful and has led to the theory that geographic area and isolation influence species colonization, extinction and speciation such that larger islands have more species and isolated islands have fewer species (that is, positive species-area and negative species-isolation relationships). However, experimental tests of this theory have been limited, owing to the difficulty in experimental manipulation of islands at the scales at which speciation and long-distance colonization are relevant. Here we have used the human-aided transport of exotic anole lizards among Caribbean islands as such a test at an appropriate scale. In accord with theory, as anole colonizations have increased, islands impoverished in native species have gained the most exotic species, the past influence of speciation on island biogeography has been obscured, and the species-area relationship has strengthened while the species-isolation relationship has weakened. Moreover, anole biogeography increasingly reflects anthropogenic rather than geographic processes. Unlike the island biogeography of the past that was determined by geographic area and isolation, in the Anthropocene--an epoch proposed for the present time interval--island biogeography is dominated by the economic isolation of human populations. PMID:25254475
Full Text Available Multiobjective optimization involves minimizing or maximizing multiple objective functions subject to a set of constraints. In this study, a novel constrained multiobjective biogeography optimization algorithm (CMBOA is proposed. It is the first biogeography optimization algorithm for constrained multiobjective optimization. In CMBOA, a disturbance migration operator is designed to generate diverse feasible individuals in order to promote the diversity of individuals on Pareto front. Infeasible individuals nearby feasible region are evolved to feasibility by recombining with their nearest nondominated feasible individuals. The convergence of CMBOA is proved by using probability theory. The performance of CMBOA is evaluated on a set of 6 benchmark problems and experimental results show that the CMBOA performs better than or similar to the classical NSGA-II and IS-MOEA.
Michael N Dawson
Full Text Available The opportunity to reflect broadly on the accomplishments, prospects, and reach of a field may present itself relatively infrequently. Each biennial meeting of the International Biogeography Society showcases ideas solicited and developed largely during the preceding year, by individuals or teams from across the breadth of the discipline. Here, we highlight challenges, developments, and opportunities in biogeography from that biennial synthesis. We note the realized and potential impact of rapid data accumulation in several fields, a renaissance for inter-disciplinary research, the importance of recognizing the evolution-ecology continuum across spatial and temporal scales and at different taxonomic, phylogenetic and functional levels, and re-exploration of classical assumptions and hypotheses using new tools. However, advances are taxonomically and geographically biased, key theoretical frameworks await tools to handle, or strategies to simplify, the biological complexity seen in empirical systems. Current threats to biodiversity require unprecedented integration of knowledge and development of predictive capacity that may enable biogeography to unite its descriptive and hypothetico-deductive branches and establish a greater role within and outside academia.
Richardson, Timothy; Whittaker, R.J.; Whittaker, Robert J.
for integrating information from numerous disparate sources; special challenges involving invasive species; and the crucial issue of determining how elements of biodiversity are likely to respond to rapid climate change. One paper provides a synthesis of requirements for a robust conservation biogeography...
Stearns, Jennifer C.; Michael D. J. Lynch; Senadheera, Dilani B.; Howard C. Tenenbaum; Michael B. Goldberg; Cvitkovitch, Dennis G.; Kenneth Croitoru; Gabriel Moreno-Hagelsieb; Neufeld, Josh D.
We present bacterial biogeography as sampled from the human gastrointestinal tract of four healthy subjects. This study generated >32 million paired-end sequences of bacterial 16S rRNA genes (V3 region) representing >95,000 unique operational taxonomic units (OTUs; 97% similarity clusters), with >99% Good's coverage for all samples. The highest OTU richness and phylogenetic diversity was found in the mouth samples. The microbial communities of multiple biopsy sites within the colon were highl...
J Bennie; JP Duffy; R Inger; KJ Gaston
The majority of mammal species are nocturnal, but many are diurnal (active during the day), crepuscular (active mostly during twilight), or cathemeral (active during hours of daylight and darkness). These different strategies for regulating activity over a 24-h cycle are associated with suites of adaptations to light or semidarkness. The biogeography of these time partitioning strategies is, however, poorly understood. We show that global patterns in mammal diversity with different diel activ...
Adams, Joseph P.
This biogeography module is designed for students wishing to study evolutionary interrelationships with the physical environment. Topics studied include various aspects of historical biogeography and evolution. Categories included are: (1) barriers to the dispersal or organisms, (2) the zoogeographic regions, (3) genetic change, (4) selection, and…
Full Text Available Proceedings of the Sixth biennial conference of the International Biogeography Society, an international and interdisciplinary society contributing to the advancement of all studies of the geography of nature. Held at Miami, Florida, USA, 9 – 13 January 2013.Abstracts include:(i the Opening, MacArthur & Wilson Award and Alfred Russel Award Plenary Lectures;(ii four symposia entitled "Island Biogeography: New Syntheses", "Beyond Bergmann: New perspectives on the biogeography of traits", "The Convergence of Conservation Paleontology and Biogeography" and "Predicting species and biodiversity in a warmer world: are we doing a good job?";(iii oral presentations from contributed papers on Phylogeography, Marine Biogeography, Biogeography of the Anthropocene, Hot Topics in biogeography, Island Biogeography, Neotropical Biogeography, Global Change Biogeography, Historical and Paleo-biogeography, Conservation Biogeography and Global-Scale Biogeography; and(iv contributions presented as posters on Phylogeography, Geospatial techniques and land cover, Biodiversity gradients and macroecology, Biogeography of traits, Island Biogeography, Neotropical Biogeography, Conservation Biogeography, Disturbance and Disease Biogeography, Climate Change Biogeography and Historical and Paleo-Biogeography.
The biogeography of nearshore benthic invertebrates in the Gulf of Maine was studied to compare recent data with historical biogeographic studies, define physical-chemical factors affecting species distributions, and provide information needed to calibrate benthic indices of envi...
Ricklefs, Robert E.; David G Jenkins
Although ecology and biogeography had common origins in the natural history of the nineteenth century, they diverged substantially during the early twentieth century as ecology became increasingly hypothesis-driven and experimental. This mechanistic focus narrowed ecology's purview to local scales of time and space, and mostly excluded large-scale phenomena and historical explanations. In parallel, biogeography became more analytical with the acceptance of plate tectonics and the development ...
Chow, Cheryl-Emiliane T; Suttle, Curtis A
Viral ecology is a rapidly progressing area of research, as molecular methods have improved significantly for targeted research on specific populations and whole communities. To interpret and synthesize global viral diversity and distribution, it is feasible to assess whether macroecology concepts can apply to marine viruses. We review how viral and host life history and physical properties can influence viral distribution in light of biogeography and metacommunity ecology paradigms. We highlight analytical approaches that can be applied to emerging global data sets and meta-analyses to identify individual taxa with global influence and drivers of emergent properties that influence microbial community structure by drawing on examples across the spectrum of viral taxa, from RNA to ssDNA and dsDNA viruses. PMID:26958906
Jun WEN; Qiu-Yun (Jenny) XIANG; Hong QIAN; Jian-hua LI; Xiao-Quan WANG; Stefanie M. ICKERT-BOND
@@ The study of biogeography has benefited from the exponential increase of DNA sequence data from recent molecular systematic studies, the development of analytical methods in the last decade concerning divergence time estimation and geographic area analyses, and the availability of large-scale distribution data of species in many groups of organisms. The underlying principle of divergence time estimation from DNA and protein data is that sequence divergence depends on the product of evolutionary rate and time. With their molecular clock hypothesis, Zuckerkandl and Pauling (1965) separated rates of molecular evolution from time by incorporating fossil evidence. Originally, a constant rate of sequence evolution was assumed, but soon it became evident that many data sets do not obey the constant rate assumption of a strict molecular clock.
Full Text Available Biogeography based optimization (BBO is a new stochastic force based on the science of biogeography. Biogeography is the schoolwork of geographical allotment of biological organisms. BBO utilizes migration operator to share information between the problem solutions. The problem solutions are known as habitats and sharing of features is called migration. In this paper, BBO algorithm is developed to optimize the current excitations of concentric circular antenna arrays (CCAA. Concentric Circular Antenna Array (CCAA has numerous attractive features that make it essential in mobile and communication applications. The goal of the optimization is to reduce the side lobe levels and the primary lobe beam width as much as possible. To confirm the capabilities of BBO, three different CCAA antennas of different sizes are taken. The results obtained by BBO are compared with the Real coded Genetic Algorithm (RGA, Craziness based Particle Swarm Optimization (CRPSO and Hybrid Evolutionary Programming (HEP.
Some aspects of the new instrumentalization and methodological elements that make up information systems in biodiversity (ISB) are described. The use of accurate geographically referenced data allows a broad range of available sources: natural history collections and scientific literature require the use of databases and geographic information systems (GIS). The conceptualization of ISB and GIS, based in the use of extensive data bases, has implied detailed modeling and the construction of authoritative archives: exhaustive catalogues of nomenclature and synonymies, complete bibliographic lists, list of names proposed, historical-geographic gazetteers with localities and their synonyms united under a global positioning system which produces a geospheric conception of the earth and its biota. Certain difficulties in the development of the system and the construction of the biological databases are explained: quality control of data, for example. The use of such systems is basic in order to respond to many questions at the frontier of current studies of biodiversity and conservation. In particular, some applications in biogeography and their importance for modeling distributions, to identify and contrast areas of endemism and biological richness for conservation, and their use as tools in what we identify as predictive and experimental faunistics are detailed. Lastly, the process as well as its relevance is emphasized at national and regional levels
Krause, Dale C.; Angel, Martin V.
Pelagic biogeography deals with the large scale distributional patterns of pelagic organisms in the world's oceans, their origins through evolution and the changes in ocean morphology during the geological past, and the factors which currently control and maintain them. The knowledge it generates has a wide variety of uses in science, both basic and applied, and in socio-economics. Its products include: (1) Distributional data compiled in data bases, maps and atlases; (2) Explanatory scientific and non-scientific publications on the distributions and their implications; (3) Standardisation of methodologies; (4) Trained specialists; (5) Advice to society on oceanic aspects of global resource management; and (6) Assessments of oceanic biodiversity in relation to the Biodiversity Convention. The immediate users of this knowledge include oceanographers in other disciplines, ecologists, applied scientists and engineers, resource managers, fishermen, environmentalists, teachers, international lawuers and policy-makers. At present the largest users are the natural resource managers seeking to optimise and to sustain the resource for which they are responsible. There is a considerable body of national and international legislation which is underpinned by biogeographical information. Similarly much of our understanding about past climate which is being used to predict future trends, is based on applying information on present-day distributional patterns to the interpretation of the fossil record in marine sediments. Global change, in the ocean, the atmosphere and on land, is strongly modulated by the feedback between marine organisms, nutrients and greenhouse gases. The marked coherence observed between the distributions of physical, chemical and biological patterns suggest that the process involved in this feedback are linked with pelagic community structure. Remote sensing of sea-surface properties and the heat content of the mixed-layer, offer considerable potential for
Kaur, Kiranjot; Rattan, Munish; Singh Patterh, Manjeet
Biogeography-based optimisation (BBO) is a novel population-based global optimisation algorithm that is stimulated by the science of biogeography. The mathematical models of biogeography describe how a species arises, migrates from one habitat (Island) to another or gets extinct. BBO searches for the global optimum mainly through two steps: migration and mutation. These steps are controlled by immigration and emigration rates of the species in the habitat which are also used to share information between the habitats. In this paper, BBO has been applied to Cognitive Radio (CR) system for optimising its various transmission parameters to meet the quality of service (QoS) that is defined by the user in terms of minimum transmit power, minimum bit error rate (BER), maximum throughput, minimum interference and maximum spectral efficiency. To confirm the capability of biogeography-based optimisation algorithm, the results obtained by BBO are compared with that obtained by using genetic algorithm (GA) for the various QoS parameters, and it has been observed that BBO outperforms GA in system optimisation.
Biogenic aerosols are relevant for the Earth system, climate, and public health on local, regional, and global scales. Up to now, however, little is known about the diversity and biogeography of airborne microorganisms. We present the first DNA-based analysis of airborne fungi on...
Phylogenetic analyses of extant Juglans (Juglandaceae) using five cpDNA intergenic spacer (IGS) sequences (trnT-trnF, psbA-trnH, atpB-rbcL, trnV-16S rRNA, and trnS-trnfM) were performed to elucidate the origin, diversification, historical biogeography, and evolutionary relationships within the genus...
Roč. 2009, č. 372691 (2009), s. 1-11. ISSN 1687-708X Grant ostatní: 6th Framework Programme(XE) GOCE-2003-010284 EDEN Institutional research plan: CEZ:AV0Z60930519 Keywords : Bhanja virus * biogeography * arbovirus es Subject RIV: EE - Microbiology, Virology
Capinha, César; Essl, Franz; Seebens, Hanno; Moser, Dietmar; Pereira, Henrique Miguel
It has been argued that globalization in human-mediated dispersal of species breaks down biogeographic boundaries, yet empirical tests are still missing. We used data on native and alien ranges of terrestrial gastropods to analyze dissimilarities in species composition among 56 globally distributed regions. We found that native ranges confirm the traditional biogeographic realms, reflecting natural dispersal limitations. However, the distributions of gastropods after human transport are primarily explained by the prevailing climate and, to a smaller extent, by distance and trade relationships. Our findings show that human-mediated dispersal is causing a breakdown of biogeographic barriers, and that climate and to some extent socioeconomic relationships will define biogeography in an era of global change. PMID:26068851
Full Text Available In present times, there is a clear and growing need for applying theoretical biogeographic achievements in improving the state of biodiversity and conservation. Conceptual principles of conservation biogeography take the research into the relationship between fundamental biogeographic principles and the need for their appliance in nature conservation as the basic theory model, based upon biogeographic studies of isolated ranges. This paper is meant to point out the differences between spatial and functional isolation and the effects these have on the stability of populations and species. In light of this need to apply theories in biodiversity and nature conservation, it is important to research not only the processes that depend solely upon natural factors, but also those that are caused by a number of human-induced changes, e.g. habitat fragmentation, climate change or biotic homogenization.
Daniel J. Falvo
Current approaches to biogeography are based on organismic biology. Certain biogeographical phenomena, however, cannot be fully understood using organismic approaches to biogeography. I employed an approach based on molecular biology and biochemistry that I call genotype by environment biogeography in order to provide a more complete understanding of why the dispersal of rice blast disease is less efficient in fields planted with mixtures of rice varieties. In a case study of an upland ricefi...
Rosemary G. Gillespie
Full Text Available Biogeography is a dynamic field that has transformed dramatically over the last few decades from being necessarily descriptive to become a rigorous science. Major recent areas of growth have included phylogenetics and phylogeography, microbial biogeography and metagenomics, and macroecology. However, the welcome recent deluge of massive amounts of data, in particular from genomics, museum specimens, and field observations, as well as environmental information, is posing a huge challenge to the field. The society has several key roles, not only to serve as a home for researchers in the field and enabling interaction among them, but also: (1 to provide a forum to facilitate awareness and use of rapidly developing tools and data; (2 to encourage a solid foundation in organismal research, with emphasis on field and museum based resources; (3 to promote global connections; and (4 to cultivate interdisciplinarity, such that the predictive capabilities of the field can be used to inform management and policy.
Ali R. Alroomi
Full Text Available Biogeography-based optimization (BBO is a new population-based evolutionary algorithm and is based on an old theory of island biogeography that explains the geographical distribution of biological organisms. BBO was introduced in 2008 and then a lot of modifications were employed to enhance its performance. This paper proposes two modifications; firstly, modifying the probabilistic selection process of the migration and mutation stages to give a fairly randomized selection for all the features of the islands. Secondly, the clear duplication process after the mutation stage is sized to avoid any corruption on the suitability index variables. The obtained results through wide variety range of test functions with different dimensions and complexities proved that the BBO performance can be enhanced effectively without using any complicated form of the immigration and emigration rates. This essential modification has to be considered as an initial step for any other modification.
Lin, Wei [Institute of Geology and Geophysics; Bazylinski, Dennis A [Ames Laboratory; Xiao, Tian [Chinese Academy of Sciences; Wu, Long-Fei [v; Pan, Yongxin [Institute of Geology and Geophysics
Magnetotactic bacteria (MTB) are unique in their ability to synthesize intracellular nano-sized minerals of magnetite and/or greigite magnetosomes for magnetic orientation. Thus, they provide an excellent model system to investigate mechanisms of biomineralization. MTB play important roles in bulk sedimentary magnetism and have numerous versatile applications in paleoenvironmental reconstructions, and biotechnological and biomedical fields. Significant progress has been made in recent years in describing the composition of MTB communities and distribution through innovative cultivation-dependent and -independent techniques. In this review, the most recent contributions to the field of diversity and biogeography of MTB are summarized and reviewed. Emphasis is on the novel insights into various factors/processes potentially affecting MTB community distribution. An understanding of the present-day biogeography of MTB, and the ruling parameters of their spatial distribution, will eventually help us predict MTB community shifts with environmental changes and assess their roles in global iron cycling.
Lin, Wei; Bazylinski, Dennis A; Xiao, Tian; Wu, Long-Fei; Pan, Yongxin
Magnetotactic bacteria (MTB) are unique in their ability to synthesize intracellular nano-sized minerals of magnetite and/or greigite magnetosomes for magnetic orientation. Thus, they provide an excellent model system to investigate mechanisms of biomineralization. MTB play important roles in bulk sedimentary magnetism and have numerous versatile applications in paleoenvironmental reconstructions, and biotechnological and biomedical fields. Significant progress has been made in recent years in describing the composition of MTB communities and distribution through innovative cultivation-dependent and -independent techniques. In this review, the most recent contributions to the field of diversity and biogeography of MTB are summarized and reviewed. Emphasis is on the novel insights into various factors/processes potentially affecting MTB community distribution. An understanding of the present-day biogeography of MTB, and the ruling parameters of their spatial distribution, will eventually help us predict MTB community shifts with environmental changes and assess their roles in global iron cycling. PMID:24148107
Antônio F. Carvalho
Full Text Available Discussions regarding Polistinae biogeography in the last two decades rarely associated current patterns of distribution with environmental changes. This well-known and very diverse group of insects is highly endemic in the Neotropics, but environmental factors influencing the enormous biological diversity in the region are not well established. Exploring evidence on the two main hypotheses concerning the origins and early colonization processes of paper wasps we position in favor of the Gondwanan hypothesis and discuss change-promoter processes in the Neotropics whose effects might have altered the distributions and facilitated the speciation of Polistinae in the region. Furthermore, based on recent advances in biogeography, mostly in the integration of ecological and evolutionary information, we highlight directions for future biogeographical research within the group.
A review is given of (mainly recent) work on the biodiversity, ecology, biogeography and practical importance of marine parasites. Problems in estimating species numbers have been thoroughly discussed for free-living species, and the main points of these discussions are reviewed here. Even rough estimates of the richness of most parasite groups in the oceans are premature for the following reasons: species numbers of host groups, in particular in the deep sea and the meiofauna, are not known; most host groups have been examined only insufficiently for parasites or not at all; even in some of the best known groups, latitudinal, longitudinal and depth gradients in species richness are only poorly understood or not known at all; effects of hosts on parasite morphology and geographical variation have been studied only in a few cases; there are few studies using techniques of molecular biology to distinguish sibling species. Estimates of species richness in the best known groups, trematodes, monogeneans and copepods of marine fishes, are given. Parasites are found in almost all taxa of eukaryotes, but most parasitic species are concentrated in a few taxa. Important aspects of the ecology of marine parasites are discussed. It is emphasized that host specificity and host ranges should be distinguished, and an index that permits calculation of host specificity is discussed. The same index can be applied to measure site specificity. Central problems in ecology are the importance of interspecific competition and whether equilibrium or non-equilibrium conditions prevail. Marine parasites are among the few groups of organisms that have been extensively examined in this regard. A holistic approach, i.e. application of many methods, has unambiguously shown that metazoan ecto- (and probably endo-) parasites of marine fish live in largely non-saturated niche space under non-equilibrium conditions, i.e. they live in assemblages rather than in communities structured by competition
Based on the revision of abundant bibliography, commentaries are made in relation to the eco geographical island theory proposed by Macarthur- Wilson and over its impact as well as the implications and limitations generated in the application of the theory in research related to biogeography, ecology, and conservation biology. We emphasize that the model served to stimulate a great deal of research and generate new concepts, such as Minimal Viable population (MVP)
Martiny, AC; Tai, APK; D. Veneziano; F. Primeau; Chisholm, SW
Summary In order to expand our understanding of the diversity and biogeography of Prochlorococcus ribotypes, we PCR-amplified, cloned and sequenced the 16S/23S rRNA ITS region from sites in the Atlantic and Pacific oceans. Ninety-three per cent of the ITS sequences could be assigned to existing Prochlorococcus clades, although many novel subclades were detected. We assigned the sequences to operational taxonomic units using a graduated scale of sequence identity from 80% to 99.5% and correlat...
Dexter, K.G.; Smart, B.; Baldauf, C.;
To provide an inter-continental overview of the floristics and biogeography of drought-adapted tropical vegetation formations, we compiled a dataset of inventory plots in South America (n=93), Africa (n=84), and Asia (n=92) from savannas (subject to fire), seasonally dry tropical forests (not...... similar vegetation formations (e.g. savannas) are floristically highly dissimilar. Neotropical moist forest, savanna and seasonally dry tropical forest are floristically distinct, but elsewhere there is no clear floristic division of savanna and seasonally dry tropical forest, though moist and dry...... ecology, biology and conservation of savannas and seasonally dry tropical forests may be difficult....
Full Text Available This paper is dedicated to the optimization of nonlinear controllers basing of an enhanced Biogeography Based Optimization (BBO approach. Indeed, The BBO is combined to a predator and prey model where several predators are used with introduction of a modified migration operator to increase the diversification along the optimization process so as to avoid local optima and reach the optimal solution quickly. The proposed approach is used in tuning the gains of PID controller for nonlinear systems. Simulations are carried out over a Mass spring damper and an inverted pendulum and has given remarkable results when compared to genetic algorithm and BBO.
Lau, Stanley C K; Zhang, Rui; Brodie, Eoin L; Piceno, Yvette M; Andersen, Gary; Liu, Wen-Tso
Knowledge about the biogeography of marine bacterioplankton on the global scale in general and in Southeast Asia in particular has been scarce. This study investigated the biogeography of bacterioplankton community in Singapore seawaters. Twelve stations around Singapore island were sampled on different schedules over 1 year. Using PCR-DNA fingerprinting, DNA cloning and sequencing, and microarray hybridization of the 16S rRNA genes, we observed clear spatial variations of bacterioplankton diversity within the small area of the Singapore seas. Water samples collected from the Singapore Strait (south) throughout the year were dominated by DNA sequences affiliated with Cyanobacteria and Alphaproteobacteria that were believed to be associated with the influx of water from the open seas in Southeast Asia. On the contrary, water in the relatively polluted Johor Strait (north) were dominated by Betaproteobacteria, Gammaproteobacteria, and Bacteroidetes and that were presumably associated with river discharge and the relatively eutrophic conditions of the waterway. Bacterioplankton diversity was temporally stable, except for the episodic surge of Pseudoalteromonas, associated with algal blooms. Overall, these results provide valuable insights into the diversity of bacterioplankton communities in Singapore seas and the possible influences of hydrological conditions and anthropogenic activities on the dynamics of the communities. PMID:23237658
Full Text Available Phylogeny is an evolutionary reconstruction of the past relationships of DNA or protein sequences and it can further be used as a tool to assess population structuring, genetic diversity and biogeographic patterns. In the microbial world, the concept that everything is everywhere is widely accepted. However, it is much debated whether microbes are easily dispersed globally or whether they, like many macro-organisms, have historical biogeographies. Biogeography can be defined as the science that documents the spatial and temporal distribution of a given taxa in the environment at local, regional and continental scales. Speciation, extinction and dispersal are proposed to explain the generation of biogeographic patterns. Cyanobacteria are a diverse group of microorganisms that inhabit a wide range of ecological niches and are well known for their toxic secondary metabolite production. Knowledge of the evolution and dispersal of these microorganisms is still limited, and further research to understand such topics is imperative. Here, we provide a compilation of the most relevant information regarding these issues to better understand the present state of the art as a platform for future studies, and we highlight examples of both phylogenetic and biogeographic studies in non-symbiotic cyanobacteria and cyanotoxins.
Full Text Available Biogeography based optimization (BBO is a new competitive population-based algorithm inspired by biogeography. It simulates the migration of species in nature to share information. A new hybrid BBO (HBBO is presented in the paper for constrained optimization. By combining differential evolution (DE mutation operator with simulated binary crosser (SBX of genetic algorithms (GAs reasonably, a new mutation operator is proposed to generate promising solution instead of the random mutation in basic BBO. In addition, DE mutation is still integrated to update one half of population to further lead the evolution towards the global optimum and the chaotic search is introduced to improve the diversity of population. HBBO is tested on twelve benchmark functions and four engineering optimization problems. Experimental results demonstrate that HBBO is effective and efficient for constrained optimization and in contrast with other state-of-the-art evolutionary algorithms (EAs, the performance of HBBO is better, or at least comparable in terms of the quality of the final solutions and computational cost. Furthermore, the influence of the maximum mutation rate is also investigated.
Escobar, Luis E.; Craft, Meggan E.
Mapping disease transmission risk is crucial in public and animal health for evidence based decision-making. Ecology and epidemiology are highly related disciplines that may contribute to improvements in mapping disease, which can be used to answer health related questions. Ecological niche modeling is increasingly used for understanding the biogeography of diseases in plants, animals, and humans. However, epidemiological applications of niche modeling approaches for disease mapping can fail to generate robust study designs, producing incomplete or incorrect inferences. This manuscript is an overview of the history and conceptual bases behind ecological niche modeling, specifically as applied to epidemiology and public health; it does not pretend to be an exhaustive and detailed description of ecological niche modeling literature and methods. Instead, this review includes selected state-of-the-science approaches and tools, providing a short guide to designing studies incorporating information on the type and quality of the input data (i.e., occurrences and environmental variables), identification and justification of the extent of the study area, and encourages users to explore and test diverse algorithms for more informed conclusions. We provide a friendly introduction to the field of disease biogeography presenting an updated guide for researchers looking to use ecological niche modeling for disease mapping. We anticipate that ecological niche modeling will soon be a critical tool for epidemiologists aiming to map disease transmission risk, forecast disease distribution under climate change scenarios, and identify landscape factors triggering outbreaks. PMID:27547199
Dutkiewicz, S.; Ward, B. A.; Scott, J. R.; Follows, M. J.
We examine the sensitivity of the biogeography of nitrogen fixers to a warming climate and increased aeolian iron deposition in the context of a global earth system model. We employ concepts from the resource-ratio theory to provide a simplifying and transparent interpretation of the results. First we demonstrate that a set of clearly defined, easily diagnosed provinces are consistent with the theory. Using this framework we show that the regions most vulnerable to province shifts and changes in diazotroph biogeography are the equatorial and South Pacific, and central Atlantic. Warmer and dustier climates favor diazotrophs due to an increase in the ratio of supply rate of iron to fixed nitrogen. We suggest that the emergent provinces could be a standard diagnostic for global change models, allowing for rapid and transparent interpretation and comparison of model predictions and the underlying mechanisms. The analysis suggests that monitoring of real world province boundaries, indicated by transitions in surface nutrient concentrations, would provide a clear and easily interpreted indicator of ongoing global change.
Escobar, Luis E; Craft, Meggan E
Mapping disease transmission risk is crucial in public and animal health for evidence based decision-making. Ecology and epidemiology are highly related disciplines that may contribute to improvements in mapping disease, which can be used to answer health related questions. Ecological niche modeling is increasingly used for understanding the biogeography of diseases in plants, animals, and humans. However, epidemiological applications of niche modeling approaches for disease mapping can fail to generate robust study designs, producing incomplete or incorrect inferences. This manuscript is an overview of the history and conceptual bases behind ecological niche modeling, specifically as applied to epidemiology and public health; it does not pretend to be an exhaustive and detailed description of ecological niche modeling literature and methods. Instead, this review includes selected state-of-the-science approaches and tools, providing a short guide to designing studies incorporating information on the type and quality of the input data (i.e., occurrences and environmental variables), identification and justification of the extent of the study area, and encourages users to explore and test diverse algorithms for more informed conclusions. We provide a friendly introduction to the field of disease biogeography presenting an updated guide for researchers looking to use ecological niche modeling for disease mapping. We anticipate that ecological niche modeling will soon be a critical tool for epidemiologists aiming to map disease transmission risk, forecast disease distribution under climate change scenarios, and identify landscape factors triggering outbreaks. PMID:27547199
Full Text Available We examine the sensitivity of the biogeography of nitrogen fixers to a warming climate and increased aeolian iron deposition in the context of a global Earth System Model. We employ concepts from Resource Ratio Theory to provide a simplifying and transparent interpretation of the results. First we demonstrate that a set of clearly defined, easily diagnosed provinces are consistent with the theory. Using the framework we show that the regions most vulnerable to province shifts and changes in diazotroph biogeography are the Equatorial and South Pacific, and central Atlantic. Warmer and dustier climates favor diazotrophs due to an increase in the ratio of supply rate of iron to fixed nitrogen. The analysis suggests that monitoring of real world province boundaries, indicated by transitions in surface nutrient concentrations, would provide a clear and easily interpreted indicator of ongoing global change. We suggest that the emergent provinces could be a standard diagnostic for global change models, allowing for rapid and transparent interpretation and comparison of model predictions and the underlying mechanisms.
Full Text Available We examine the sensitivity of the biogeography of nitrogen fixers to a warming climate and increased aeolian iron deposition in the context of a global earth system model. We employ concepts from the resource-ratio theory to provide a simplifying and transparent interpretation of the results. First we demonstrate that a set of clearly defined, easily diagnosed provinces are consistent with the theory. Using this framework we show that the regions most vulnerable to province shifts and changes in diazotroph biogeography are the equatorial and South Pacific, and central Atlantic. Warmer and dustier climates favor diazotrophs due to an increase in the ratio of supply rate of iron to fixed nitrogen. We suggest that the emergent provinces could be a standard diagnostic for global change models, allowing for rapid and transparent interpretation and comparison of model predictions and the underlying mechanisms. The analysis suggests that monitoring of real world province boundaries, indicated by transitions in surface nutrient concentrations, would provide a clear and easily interpreted indicator of ongoing global change.
Patzenhauerová, Hana; Matur, Ferhat; Mikula, Ondřej; Šumbera, R.; Verheyen, E.; Chitaukali, W. N.; Bryja, Josef
Kwaluseni: University of Swaziland, 2011. s. 32. [African Small Mammal Symposium /11./. 03.08.2011-08.08.2011, Kwaluseni] Institutional research plan: CEZ:AV0Z60930519 Keywords : Praomys delectorum * biogeography * Eastern Africa Subject RIV: EG - Zoology
Kalkman, Vincent J.
he papers in which are part of this theses describe the global diversity and conservation status of damselflies and dragonflies, contain a moleculair revision of the damselflies and discuss the biogeography of damselflies and dragonflies in the Australasian region.
Joaquín Hortal; Karen Faller; Kenneth Feeley; Richard Field; Catherine Graham; François Guilhaumon; Daniel Gavin
Proceedings of the Sixth biennial conference of the International Biogeography Society, an international and interdisciplinary society contributing to the advancement of all studies of the geography of nature. Held at Miami, Florida, USA, 9 – 13 January 2013.Abstracts include:(i) the Opening, MacArthur & Wilson Award and Alfred Russel Award Plenary Lectures;(ii) four symposia entitled "Island Biogeography: New Syntheses", "Beyond Bergmann: New perspectives on the biogeography of traits", ...
Full Text Available Biogenic aerosols are relevant for the Earth system, climate, and public health on local, regional, and global scales. Up to now, however, little is known about the diversity and biogeography of airborne microorganisms. We present the first DNA-based analysis of airborne fungi on global scales, showing pronounced geographic patterns and boundaries. In particular we find that the ratio of species richness between Basidiomycota and Ascomycota is much higher in continental air than in marine air. This may be an important difference between the "blue ocean" and "green ocean" regimes in the formation of clouds and precipitation, for which fungal spores can act as nuclei. Our findings also suggest that air flow patterns and the global atmospheric circulation are important for the understanding of global changes in biodiversity.
Fröhlich-Nowoisky, J.; Burrows, S. M.; Xie, Z.; Engling, G.; Solomon, P. A.; Fraser, M. P.; Mayol-Bracero, O. L.; Artaxo, P.; Begerow, D.; Conrad, R.; Andreae, M. O.; Després, V. R.; Pöschl, U.
Biogenic aerosols are relevant for the Earth system, climate, and public health on local, regional, and global scales. Up to now, however, little is known about the diversity and biogeography of airborne microorganisms. We present the first DNA-based analysis of airborne fungi on global scales, showing pronounced geographic patterns and boundaries. In particular we find that the ratio of species richness between Basidiomycota and Ascomycota is much higher in continental air than in marine air. This may be an important difference between the "blue ocean" and "green ocean" regimes in the formation of clouds and precipitation, for which fungal spores can act as nuclei. Our findings also suggest that air flow patterns and the global atmospheric circulation are important for the understanding of global changes in biodiversity.
Full Text Available Biogenic aerosols are relevant for the Earth system, climate, and public health on local, regional, and global scales. Up to now, however, little is known about the diversity and biogeography of airborne microorganisms. We present the first DNA-based analysis of airborne fungi on global scales, showing pronounced geographic patterns and boundaries. In particular we found that the ratio of species richness between Basidiomycota and Ascomycota is much higher in continental air than in marine air. This may be an important difference between the "blue ocean" and "green ocean" regimes in the formation of clouds and precipitation, for which fungal spores can act as nuclei. Our findings also suggest that air flow patterns and the global atmospheric circulation are important for the evolution of microbial ecology and for the understanding of global changes in biodiversity.
Rosindell, James; Phillimore, Albert B
Islands acquire species through immigration and speciation. Models of island biogeography should capture both processes; however quantitative island biogeography theory has either neglected speciation or treated it unrealistically. We introduce a model where the dominance of immigration on small and near islands gives way to an increasing role for speciation as island area and isolation increase. We examine the contribution of immigration and speciation to the avifauna of 35 archipelagoes and find, consistent with our model, that the zone of radiation comprises two regions: endemic species diverged from mainland sister-species at intermediate isolation and from insular sister-species at higher levels of isolation. Our model also predicts species-area curves in accord with existing research and makes new predictions about species ages and abundances. We argue that a paucity of data and theory on species abundances on isolated islands highlights the need for island biogeography to be reconnected with mainstream ecology. PMID:21481125
Daniel J. Falvo
Full Text Available Current approaches to biogeography are based on organismic biology. Certain biogeographical phenomena, however, cannot be fully understood using organismic approaches to biogeography. I employed an approach based on molecular biology and biochemistry that I call genotype by environment biogeography in order to provide a more complete understanding of why the dispersal of rice blast disease is less efficient in fields planted with mixtures of rice varieties. In a case study of an upland ricefield in the Philippines, I found that planting varietal mixtures results in a form of effective blast control that I call intrafield gene deployment. I suggest that intrafield gene deployment be used to design more effective methods of blast control in intensive rice agriculture.
Ruiz-Calderon, Jean F; Cavallin, Humberto; Song, Se Jin; Novoselac, Atila; Pericchi, Luis R; Hernandez, Jean N; Rios, Rafael; Branch, Oralee H; Pereira, Henrique; Paulino, Luciana C; Blaser, Martin J; Knight, Rob; Dominguez-Bello, Maria G
Westernization has propelled changes in urbanization and architecture, altering our exposure to the outdoor environment from that experienced during most of human evolution. These changes might affect the developmental exposure of infants to bacteria, immune development, and human microbiome diversity. Contemporary urban humans spend most of their time indoors, and little is known about the microbes associated with different designs of the built environment and their interaction with the human immune system. This study addresses the associations between architectural design and the microbial biogeography of households across a gradient of urbanization in South America. Urbanization was associated with households' increased isolation from outdoor environments, with additional indoor space isolation by walls. Microbes from house walls and floors segregate by location, and urban indoor walls contain human bacterial markers of space use. Urbanized spaces uniquely increase the content of human-associated microbes-which could increase transmission of potential pathogens-and decrease exposure to the environmental microbes with which humans have coevolved. PMID:26933683
The uniqueness of the flora from the remote tableaux summits of the Guayana region has been explained either as the result of a long history of evolution in isolation (Lost World hypothesis or LW) or by alternating upward and downward displacements during the glacial-interglacial Quaternary cycles (Vertical Displacement hypothesis or VD). So far, the problem has been addressed solely on the basis of present-day floristic observations. This paper faces the problem from a Quaternary palaeoecology perspective using recent palynological findings in the area, comparisons with palaeoecological records from Neotropical mountains and lowlands of similar latitude, isotopic glacial-interglacial records from marine and ice cores, and different points of view about the response of organisms to Quaternary climatic changes, with emphasis on the LGM and the debate on the existence or not of Neotropical refugia. It is concluded that both LW and VD hypotheses, together with autoecological and synecological considerations, are needed to explain the present-day specialisation and endemism of the flora from the tableaux summits. The case of a highly endemic genus ( Chimantaea, Asteraceae) is analysed as an example, to illustrate the usefulness and limitations of the different arguments to account for its biogeographical pattern. Some ideas are provided for future research, including a more extensive sampling strategy, the use of molecular phylogenetics, the evaluation of the individualistic versus the community approach, and the use of island biogeography and metapopulation methods on present-day floristic data.
Nelson, Michaeline B; Martiny, Adam C; Martiny, Jennifer B H
Microorganisms drive much of the Earth's nitrogen (N) cycle, but we still lack a global overview of the abundance and composition of the microorganisms carrying out soil N processes. To address this gap, we characterized the biogeography of microbial N traits, defined as eight N-cycling pathways, using publically available soil metagenomes. The relative frequency of N pathways varied consistently across soils, such that the frequencies of the individual N pathways were positively correlated across the soil samples. Habitat type, soil carbon, and soil N largely explained the total N pathway frequency in a sample. In contrast, we could not identify major drivers of the taxonomic composition of the N functional groups. Further, the dominant genera encoding a pathway were generally similar among habitat types. The soil samples also revealed an unexpectedly high frequency of bacteria carrying the pathways required for dissimilatory nitrate reduction to ammonium, a little-studied N process in soil. Finally, phylogenetic analysis showed that some microbial groups seem to be N-cycling specialists or generalists. For instance, taxa within the Deltaproteobacteria encoded all eight N pathways, whereas those within the Cyanobacteria primarily encoded three pathways. Overall, this trait-based approach provides a baseline for investigating the relationship between microbial diversity and N cycling across global soils. PMID:27432978
Gaisin, Vasil A; Grouzdev, Denis S; Namsaraev, Zorigto B; Sukhacheva, Marina V; Gorlenko, Vladimir M; Kuznetsov, Boris B
Isolated environments such as hot springs are particularly interesting for studying the microbial biogeography. These environments create an 'island effect' leading to genetic divergence. We studied the phylogeographic pattern of thermophilic anoxygenic phototrophic bacteria, belonging to the Roseiflexus genus. The main characteristic of the observed pattern was geographic and geochronologic fidelity to the hot springs within Circum-Pacific and Alpine-Himalayan-Indonesian orogenic belts. Mantel test revealed a correlation between genetic divergence and geographic distance among the phylotypes. Cluster analysis revealed a regional differentiation of the global phylogenetic pattern. The phylogeographic pattern is in correlation with geochronologic events during the break up of Pangaea that led to the modern configuration of continents. To our knowledge this is the first geochronological scenario of intercontinental prokaryotic taxon divergence. The existence of the modern phylogeographic pattern contradicts with the existence of the ancient evolutionary history of the Roseiflexus group proposed on the basis of its deep-branching phylogenetic position. These facts indicate that evolutionary rates in Roseiflexus varied over a wide range. PMID:26826142
Hensley, Dannie A.
Until about 25 years ago, classification of the flatfishes was based on the Regan-Norman model. Beginning with the work of Amaoka in 1969, the order started to be analysed in finer detail, and in the 1980s many questions arose concerning flatfish phylogeny as expressed in the Regan-Norman model. Two of the major questions were whether the order is monophyletic and which groups within the order are monophyletic. Recent research has clarified many of these questions. Chapleau recently redefined the order based on shared derived characters, thus supporting the hypothesis of monophyly. The most recent classifications based on phylogenetic studies have split several of the traditionally recognized families. Some flatfish groups were shown to be monophyletic once certain species were excluded. As phylogenetic studies and work on the alpha-level taxonomy continue, we are beginning to see some very interesting biogeographic patterns. Some of these distribution patterns were not previously obvious due to polyphyly of some of the flatfish groups. There is still much work to be done on the systematics and biogeography of flatfishes. Some of the more important questions that remain to be addressed in future studies are the following. (1) What is the sister group of the order? (2) What is the sister group of the Southern Ocean Achiropsettidae? (3) What are the relationships of the remaining groups in the polyphyletic Pleuronectidae? (4) What are the relationships of certain genera that are excluded from recently redefined families? (5) What are the intergeneric relationships within monophyletic groups such as the Bothidae, Achiridae and Soleidae? A great deal of work at the alpha-taxonomic level with flatfishes is still needed. Especially in tropical areas, new species and great range extensions are routinely discovered. There is also a need for more ontogenetic studies of flatfishes.
Price, Andrea M; Pospelova, Vera; Coffin, Michael R S; Latimer, James S; Chmura, Gail L
Few biogeographic studies of dinoflagellate cysts include the near-shore estuarine environment. We determine the effect of estuary type, biogeography, and water quality on the spatial distribution of organic-walled dinoflagellate cysts from the Northeast USA (Maine to Delaware) and Canada (Prince Edward Island). A total of 69 surface sediment samples were collected from 27 estuaries, from sites with surface salinities >20. Dinoflagellate cysts were examined microscopically and compared to environmental parameters using multivariate ordination techniques. The spatial distribution of cyst taxa reflects biogeographic provinces established by other marine organisms, with Cape Cod separating the northern Acadian Province from the southern Virginian Province. Species such as Lingulodinium machaerophorum and Polysphaeridinium zoharyi were found almost exclusively in the Virginian Province, while others such as Dubridinium spp. and Islandinium? cezare were more abundant in the Acadian Province. Tidal range, sea surface temperature (SST), and sea surface salinity (SSS) are statistically significant parameters influencing cyst assemblages. Samples from the same type of estuary cluster together in canonical correspondence analysis when the estuaries are within the same biogeographic province. The large geographic extent of this study, encompassing four main estuary types (riverine, lagoon, coastal embayment, and fjord), allowed us to determine that the type of estuary has an important influence on cyst assemblages. Due to greater seasonal variations in SSTs and SSSs in estuaries compared to the open ocean, cyst assemblages show distinct latitudinal trends. The estuarine context is important for understanding present-day species distribution, the factors controlling them, and to better predict how they may change in the future. PMID:27547344
Reese, B. K.; Shepard, A.; St. Peter, C.; Mills, H. J.
Microbial life in deep marine sediments is widespread, metabolically active and diverse. Evidence of prokaryotic communities in sediments as deep as 800 m below the seafloor (mbsf) have been found. By recycling carbon and nutrients through biological and geochemical processes, the deep subsurface has the potential to remain metabolically active over geologic time scales. While a vast majority of the subsurface biosphere remains under studied, recent advances in molecular techniques and an increased focus on microbiological sampling during IODP expeditions have provided the initial steps toward better characterizations of the microbial communities. Coupling of geochemistry and RNA-based molecular analysis is essential to the description of the active microbial populations within the subsurface biosphere. Studies based on DNA may describe the taxa and metabolic pathways from the total microbial community within the sediment, whether the cells sampled were metabolically active, quiescent or dead. Due to a short lifespan within a cell, only an RNA-based analysis can be used to identify linkages between active populations and observed geochemistry. This study will coalesce and compare RNA sequence and geochemical data from Expeditions 316 (Nankai Trough), 320 (Pacific Equatorial Age Transect), 325 (Great Barrier Reef) and 329 (South Pacific Gyre) to evaluate the biogeography of microbial lineages actively altering the deep subsurface. The grouping of sediments allows for a wide range of geochemical environments to be compared, including two environments limited in organic carbon. Significant to this study is the use of similar extraction, amplification and simultaneous 454 pyrosequencing on all sediment populations allowing for robust comparisons with similar protocol strengths and biases. Initial trends support previously described reduction of diversity with increasing depth. The co-localization of active reductive and oxidative lineages suggests a potential cryptic
An update of the phylogeny and biogeography of mushroom coral species belonging to Fungia (Pleuractis) is presented. Among the five species of this monophyletic group, one is described as new to science. This species, Fungia seychellensis spec, nov., was discovered during the Netherlands Seychelles Expedition (1992-1993) in the framework of the Netherlands Indian Ocean Programme 1990/1995.
Rosindell, James; Hubbell, Stephen P.; Etienne, Rampal S.
A decade has now passed since Hubbell published The Unified Neutral Theory of Biodiversity and Biogeography. Neutral theory highlights the importance of dispersal limitation, speciation and ecological drift in the natural world and provides quantitative null models for assessing the role of adaptati
Brothers, Timothy S.
Uses the U.S. General Land Office Survey as a source of data for reconstruction of local presettlement vegetation patterns in the United States. Data serve as a basis for an introductory biogeography course at Indiana University, Indianapolis. Includes field exercises, questions, and tables of frequency of witness-trees records. (NL)
Schauer, Regina; Bienhold, Christina; Ramette, Alban; Harder, Jens
communities in three basins of the eastern South Atlantic Ocean to determine diversity and biogeography of bacterial communities in deep-sea surface sediments. The analysis of 16S ribosomal RNA (rRNA) gene clone libraries in each basin revealed a high diversity, representing 521 phylotypes with 98% identity...
Case, M. J.; Kim, J. B.
Assessing changes in vegetation is increasingly important for conservation planning in the face of climate change. Dynamic global vegetation models (DGVMs) are important tools for assessing such changes. DGVMs have been applied at regional scales to create projections of range expansions and contractions of plant functional types. Many DGVMs use a number of algorithms to determine the biogeography of plant functional types. One such DGVM, MC2, uses a series of decision trees based on bioclimatic thresholds while others, such as LPJ, use constraining emergent properties with a limited set of bioclimatic threshold-based rules. Although both approaches have been used widely, we demonstrate that these biogeography outputs perform poorly at continental scales when compared to existing potential vegetation maps. Specifically, we found that with MC2, the algorithm for determining leaf physiognomy is too simplistic to capture arid and semi-arid vegetation in much of the western U.S., as well as is the algorithm for determining the broadleaf and needleleaf mix in the Southeast. With LPJ, we found that the bioclimatic thresholds used to allow seedling establishment are too broad and fail to capture regional-scale biogeography of the plant functional types. In response, we demonstrate a new approach to determining the biogeography of plant functional types by integrating the climatic thresholds produced for individual tree species by a series of climate envelope models with the biogeography algorithms of MC2 and LPJ. Using this approach, we find that MC2 and LPJ perform considerably better when compared to potential vegetation maps.
Karlsson Tiselius, Andreas
Increasing habitat fragmentation and rapid global warming is changing the conditions for species populations and ecological communities around the world. This presents challenges for the maintenance of biodiversity and a dominant paradigm for conservation in fragmented habitats is given by island biogeography and metapopulation (or metacommunity) ecology. In this thesis I approach key concepts (area, connectivity and community assembly) in island biogeography and metacommunity ecology within ...
Hortal, Joaquín; Faller, Karen; Feeley, Kenneth; Field, Richard; Graham, Catherine; Guilhaumon, François; Gavin, Daniel
Proceedings of the Sixth biennial conference of the International Biogeography Society, an international and interdisciplinary society contributing to the advancement of all studies of the geography of nature. Held at Miami, Florida, USA, 9 – 13 January 2013. Abstracts include: (i) the Opening, MacArthur & Wilson Award and Alfred Russel Award Plenary Lectures; (ii) four symposia entitled "Island Biogeography: New Syntheses", "Beyond Bergmann: New perspectives on the...
Full Text Available Abstract The climatic cycles with subsequent glacial and intergalcial periods have had a great impact on the distribution and evolution of species. Using genetic analytical tools considerably increased our understanding of these processes. In this review I therefore give an overview of the molecular biogeography of Europe. For means of simplification, I distinguish between three major biogeographical entities: (i "Mediterranean" with Mediterranean differentiation and dispersal centres, (ii "Continental" with extra-Mediterranean centres and (iii "Alpine" and/or "Arctic" with recent alpine and/or arctic distribution patterns. These different molecular biogeographical patterns are presented using actual examples. Many "Mediterranean" species are differentiated into three major European genetic lineages, which are due to glacial isolation in the three major Mediterranean peninsulas. Postglacial expansion in this group of species is mostly influenced by the barriers of the Pyrenees and the Alps with four resulting main patterns of postglacial range expansions. However, some cases are known with less than one genetic lineage per Mediterranean peninsula on the one hand, and others with a considerable genetic substructure within each of the Mediterranean peninsulas, Asia Minor and the Maghreb. These structures within the Mediterranean sub-centres are often rather strong and in several cases even predate the Pleistocene. For the "Continental" species, it could be shown that the formerly supposed postglacial spread from eastern Palearctic expansion centres is mostly not applicable. Quite the contrary, most of these species apparently had extra-Mediterranean centres of survival in Europe with special importance of the perialpine regions, the Carpathian Basin and parts of the Balkan Peninsula. In the group of "Alpine" and/or "Arctic" species, several molecular biogeographical patterns have been found, which support and improve the postulates based on
Full Text Available As the usage and development of wireless sensor networks increases, problems related to these networks are becoming apparent. Dynamic deployment is one of the main topics that directly affects the performance of the wireless sensor networks. In this paper, biogeography-based optimization is applied to the dynamic deployment of static and mobile sensor networks to achieve better performance by trying to increase the coverage area of the network. A binary detection model is considered to obtain realistic results while computing the effectively covered area. Performance of the algorithm is compared with that of the artificial bee colony algorithm, Homo-H-VFCPSO and stud genetic algorithm that are also population-based optimization algorithms. Results show biogeography-based optimization can be preferable in the dynamic deployment of wireless sensor networks.
Full Text Available Biogeography-based optimization (BBO is an evolutionary algorithm inspired by biogeography, which is the study of the migration of species between habitats. A finite Markov chain model of BBO for binary problems was derived in earlier work, and some significant theoretical results were obtained. This paper analyzes the convergence properties of BBO on binary problems based on the previously derived BBO Markov chain model. Analysis reveals that BBO with only migration and mutation never converges to the global optimum. However, BBO with elitism, which maintains the best candidate in the population from one generation to the next, converges to the global optimum. In spite of previously published differences between genetic algorithms (GAs and BBO, this paper shows that the convergence properties of BBO are similar to those of the canonical GA. In addition, the convergence rate estimate of BBO with elitism is obtained in this paper and is confirmed by simulations for some simple representative problems.
Zhou, Xu; Liu, Yanheng; Li, Bin; Sun, Geng
Identifying community structures in static network misses the opportunity to capture the evolutionary patterns. So community detection in dynamic network has attracted many researchers. In this paper, a multiobjective biogeography based optimization algorithm with decomposition (MBBOD) is proposed to solve community detection problem in dynamic networks. In the proposed algorithm, the decomposition mechanism is adopted to optimize two evaluation objectives named modularity and normalized mutual information simultaneously, which measure the quality of the community partitions and temporal cost respectively. A novel sorting strategy for multiobjective biogeography based optimization is presented for comparing quality of habitats to get species counts. In addition, problem-specific migration and mutation model are introduced to improve the effectiveness of the new algorithm. Experimental results both on synthetic and real networks demonstrate that our algorithm is effective and promising, and it can detect communities more accurately in dynamic networks compared with DYNMOGA and FaceNet.
Priya Arora; Harish Kundra; Dr. V.K Panchal
Swarm Intelligence techniques expedite the configuration and collimation of the remarkable ability of group members to reason and learn in an environment of contingency and corrigendum from their peers by sharing information. This paper introduces a novel approach of fusion of two intelligent techniques generally to augment the performance of a single intelligent technique by means of information sharing. Biogeography-based optimization (BBO) is a recently developed heuristic algorithm, which...
Jean, K.; Burnside, W. R.; Carlson, L.; Smith, K; Guégan, Jean-François
Aim Our understanding of the ecology and biogeography of microbes, including those that cause human disease, lags behind that for larger species. Despite recent focus on the geographical distribution of viruses and bacteria, the overall environmental distribution of human pathogens and parasites on Earth remains incompletely understood. As islands have long inspired basic ecological insights, we aimed to assess whether the microorganisms that cause human disease in modern times follow pattern...
Gannon, Ruan; Taylor, Matthew D; Suthers, Iain M; Gray, Charles A; van der Meulen, Dylan E; Smith, James A; Payne, Nicholas L
Theoretical and laboratory studies generally show that ectotherm performance increases with temperature to an optimum, and subsequently declines. Several physiological mechanisms probably shape thermal performance curves, but responses of free-ranging animals to temperature variation will represent a compromise between these mechanisms and ecological constraints. Thermal performance data from wild animals balancing physiology and ecology are rare, and this represents a hindrance for predicting population impacts of future temperature change. We used internally implanted accelerometers near the middle of a species' geographical distribution and gill-net catch data near the species' latitudinal extremes to quantify temperature-related activity levels of a wild predatory fish (Platycephalus fuscus). We examined our data in the context of established models of thermal performance, and the relationship between thermal performance thresholds and biogeography. Acceleration data approximated a thermal performance curve, with activity peaking at 23°C but declining rapidly at higher temperatures. Gill-net catch data displayed a similar trend, with a temperature-associated increase and decrease in catch rates in temperate and tropical regions, respectively. Extrapolated estimates of zero activity (CTmin and CTmax) from the accelerometers were similar to the minimum and maximum mean monthly water temperatures experienced at the southern and northern (respectively) limits of the species distribution, consistent with performance-limited biogeography in this species. These data highlight the fundamental influence of temperature on ectotherm performance, and how thermal performance limits may shape biogeography. Biologging approaches are rarely used to examine thermal performance curves in free-ranging animals, but these may be central to understanding the trade-offs between physiology and ecology that constrain species' biogeographies and determine the susceptibility of
Feifei Dong; Dichen Liu; Jun Wu; Bingcheng Cen; Haolei Wang; Chunli Song; Lina Ke
Considering that common subsynchronous resonance controllers cannot adapt to the characteristics of the time-varying and nonlinear behavior of a power system, the cosine migration model, the improved migration operator, and the mutative scale of chaos and Cauchy mutation strategy are introduced into an improved biogeography-based optimization (IBBO) algorithm in order to design an optimal subsynchronous damping controller based on the mechanism of suppressing SSR by static var compensator (SV...
Lin, W.; Wang, Y.; Pan, Y.
A number of microorganisms are able to biomineralize iron minerals. Among them, magnetotactic bacteria (MTB) mineralize intracellular membrane-enveloped magnetite and/or greigite, known as magnetosomes that help cells to swim along the Earth's magnetic field. In recent years, MTB have become an attractive model system for investigating the biogeomagnetism. The occurrence of MTB has been reported in aquatic environments from freshwater to marine ecosystems. And, fossil magnetosomes are found to be potential carriers of natural remanent magnetization and indicators of paleoenvironmental changes. However, their distribution across heterogeneous habitats remains unclear. Here we report the diversity and biogeography of MTB from more than 20 locations from freshwater to saline habitats in eastern China. Great morphological variability was observed in MTB communities through light and transmission electron microscope observation. Phylogenetic analysis based on 16S rRNA genes has revealed that identified MTB belonged to the Alphaproteobacteria, Deltaproteobacteria, Gammaproteobacteria, and the phylum Nitrospirae. The overall composition of MTB communities was compared, and we found a restricted distribution of MTB communities across a large spatial scale with pronounced endemicity. Variation partitioning analyses indicated that the biogeography of MTB is relatively more influenced by environmental factors (e.g., salinity, sulfate, total iron, Eh, and temperature) than geographic distance. More interestingly, we found, for the first time, that the strength of the Earth's magnetic field appears to influence the biogeography of MTB, implying an impact of geophysical effects on these microorganisms. Our results infer that MTB community represents a biogeographic distribution across the studied heterogeneous environments. Knowledge of the present-day MTB biogeography may be applied towards the reconstruction of paleo-environments and assessment of contribution of bacterial
Van Houtan, Kyle S.; Francke, Devon L.; Alessi, Sarah; Jones, T. Todd; Martin, Summer L.; Kurpita, Lauren; King, Cheryl S.; Baird, Robin W.
Abstract High seas oceanic ecosystems are considered important habitat for juvenile sea turtles, yet much remains cryptic about this important life‐history period. Recent progress on climate and fishery impacts in these so‐called lost years is promising, but the developmental biogeography of hawksbill sea turtles (Eretmochelys imbricata) has not been widely described in the Pacific Ocean. This knowledge gap limits the effectiveness of conservation management for this globally endangered speci...
McClanahan, Timothy R.; Mebrahtu Ateweberhan; Darling1, Emily S.; Graham, Nicholas A. J.; Nyawira A Muthiga
Coral reefs are biodiverse ecosystems structured by abiotic and biotic factors operating across many spatial scales. Regional-scale interactions between climate change, biogeography and fisheries management remain poorly understood. Here, we evaluated large-scale patterns of coral communities in the western Indian Ocean after a major coral bleaching event in 1998. We surveyed 291 coral reef sites in 11 countries and over 30° of latitude between 2004 and 2011 to evaluate variations in coral co...
An overview of the primary approaches to seaweed biogeography is provided in light of the development of vicariance biogeography. Each approach is discussed with particular regard to the extent to which the methods and objectives are compatible with vicariance. Ecological biogeography is considered an offshoot of ecology and physiology and is more appropriate in determining current distributions of organisms and aspects of physiological ecology rather than the speciation history of monophyletic groups. The R/P quotient of Feldmann and distribution of algal life-forms do not fall within the aegis of vicariance and are considered useful only in a descriptive sense. The examination of seaweed spans propounded by Pielou is considered flawed because of the lack of dependence on monophyletic groups. The floristic school of analysis of many seaweed biogeographers is analagous to the panbiogeography of Croizat, and provides the basis for the more concrete phylogenetic hypotheses that are the basis for vicariance analysis. The latter is considered the best methodology for studying the relationship between patterns of cladogenesis and the distribution of constituent taxa.
Highlights: • BBO algorithm is capable of finding suitably optimized loading pattern. • It seems BBO reaches to better final parameter value in comparison with the PSO. • PSO exhibits faster convergence characteristics in comparison with BBO. • Even with same initial random patterns the BBO is found to outperform PSO. - Abstract: In this investigation, we developed a new optimization method, i.e., biogeography based optimization (BBO), for loading pattern optimization problem of pressurized water reactors. BBO is a novel stochastic force based on the science of biogeography. Biogeography is the schoolwork of geographical allotment of biological organisms. BBO make use of migration operator to share information between the problem solutions. The problem solutions are called as habitats and sharing of features is called migration. For the evaluation of the proposed method, we applied a multi-objective fitness function i.e., the maximization of reactivity at BOC and the flattening of power distribution are achieved efficiently and simultaneously. The neutronic calculation is done by CITATION and WIMS codes
Violle, Cyrille; Choler, Philippe; Borgy, Benjamin; Garnier, Eric; Amiaud, Bernard; Debarros, Guilhem; Diquelou, Sylvain; Gachet, Sophie; Jolivet, Claudy; Kattge, Jens; Lavorel, Sandra; Lemauviel-Lavenant, Servane; Loranger, Jessy; Mikolajczak, Alexis; Munoz, François; Olivier, Jean; Viovy, Nicolas
The effect of biodiversity on ecosystem functioning has been widely acknowledged, and the importance of the functional roles of species, as well as their diversity, in the control of ecosystem processes has been emphasised recently. However, bridging biodiversity and ecosystem science to address issues at a biogeographic scale is still in its infancy. Bridging this gap is the primary goal of the emerging field of functional biogeography. While the rise of Big Data has catalysed functional biogeography studies in recent years, comprehensive evidence remains scarce. Here, we present the rationale and the first results of a country-wide initiative focused on the C3 permanent grasslands. We aimed to collate, integrate and process large databases of vegetation relevés, plant traits and environmental layers to provide a country-wide assessment of ecosystem properties and services which can be used to improve regional models of climate and land use changes. We outline the theoretical background, data availability, and ecoinformatics challenges associated with the approach and its feasibility. We provide a case study of upscaling of leaf dry matter content averaged at ecosystem level and country-wide predictions of forage digestibility. Our framework sets milestones for further hypothesis testing in functional biogeography and earth system modelling. PMID:25908020
Full Text Available This paper presents Hybrid Biogeography algorithm for solving the multi-objective reactive power dispatch problem in a power system. Real Power Loss minimization and maximization of voltage stability margin are taken as the objectives. Artificial bee colony optimization (ABC is quick and forceful algorithm for global optimization. Biogeography-Based Optimization (BBO is a new-fangled biogeography inspired algorithm. It mainly utilizes the biogeography-based relocation operator to share the information among solutions. In this work, a hybrid algorithm with BBO and ABC is projected, and named as HBBABC (Hybrid Biogeography based Artificial Bee Colony Optimization, for the universal numerical optimization problem. HBBABC merge the searching behavior of ABC with that of BBO. Both the algorithms have different solution probing tendency like ABC have good exploration probing tendency while BBO have good exploitation probing tendency. HBBABC used to solve the reactive power dispatch problem and the proposed technique has been tested in standard IEEE30 bus test system.
Although our understanding of environmental risk assessment in temporary wetlands has been improved by the use of multi-species toxicity testing, we still know little of how landscape variables mediate the strength of, and recovery from, anthropogenic stress in such ecosystems. To bridge this research gap, we provide a theoretical framework of the response of temporary wetlands to anthropogenic disturbance along a habitat-isolation continuum based on island biogeography theory, landscape ecology and dispersal and colonization strategies of temporary wetland organisms. - Environmental risk assessment in temporary wetlands may benefit from consideration of island biogeography theory and landscape structure
Lin, W.; Pan, Y.
A number of microorganisms biomineralize intracellular or extracellular iron minerals and play essential roles in the global iron cycling. One of the most interesting examples of these types of organisms are the magnetotactic bacteria (MTB), a polyphyletic group of prokaryotes that are able to uptake iron from environments and biomineralize intracellular nano-sized iron minerals of magnetite (Fe3O4) and/or greigite (Fe3S4), known as magnetosomes. Knowledge on their potential contributions to the biogeochemical cycle of iron remains unknown because the diversity and biogeography of MTB in nature are not fully understood. Over the past years, we have extensively investigated the diversity and distribution of MTB communities from freshwater to saline habitats. Several novel yet uncultivated MTB populations were identified and characterized. By comparing our results with publicly available dataset of MTB, we revealed that the composition of MTB communities represents a biogeographic distribution across globally heterogeneous environments, and both environmental heterogeneity and geographic distance play significant roles in shaping their community composition. Building on the knowledge on MTB biogeography, we could estimate the potential contributions of MTB to the global iron cycling, e.g., the annual yield of magnetite by lacustrine MTB is estimated to be no less than 5 × 10^6 kg; while, this estimate would pronouncedly increase to an order of 10^8 kg of magnetite per year if we consider MTB communities distributed in the oceans. Our results strongly suggest that MTB communities play important roles in the present-day global iron cycling and the deposition of iron formation through geological history. On the other hand, since magnetosomes are strain-specific and could be preserved in sediments (magnetofossils), biogeography of MTB will open new avenue to paleoenvironmental studies. More research involving the ecology of natural MTB will help us better understand the
Kauserud Håvard; Carlsen Tor; Binder Manfred; Engh Ingeborg B; Skrede Inger; Bendiksby Mika
Abstract Background The fungal genus Serpula (Serpulaceae, Boletales) comprises several saprotrophic (brown rot) taxa, including the aggressive house-infecting dry rot fungus Serpula lacrymans. Recent phylogenetic analyses have indicated that the ectomycorrhiza forming genera Austropaxillus and Gymnopaxillus cluster within Serpula. In this study we use DNA sequence data to investigate phylogenetic relationships, historical biogeography of, and nutritional mode transitions in Serpulaceae. Resu...
Herrera, Nathanael D; Ter Poorten, Jan Johan; Bieler, Rüdiger; Mikkelsen, Paula M; Strong, Ellen E; Jablonski, David; Steppan, Scott J
Reconstructing historical biogeography of the marine realm is complicated by indistinct barriers and, over deeper time scales, a dynamic landscape shaped by plate tectonics. Here we present the most extensive examination of model-based historical biogeography among marine invertebrates to date. We conducted the largest phylogenetic and molecular clock analyses to date for the bivalve family Cardiidae (cockles and giant clams) with three unlinked loci for 110 species representing 37 of the 50 genera. Ancestral ranges were reconstructed using the dispersal-extinction-cladogenesis (DEC) method with a time-stratified paleogeographic model wherein dispersal rates varied with shifting tectonics. Results were compared to previous classifications and the extensive paleontological record. Six of the eight prior subfamily groupings were found to be para- or polyphyletic. Cardiidae originated and subsequently diversified in the tropical Indo-Pacific starting in the Late Triassic. Eastern Atlantic species were mainly derived from the tropical Indo-Mediterranean region via the Tethys Sea. In contrast, the western Atlantic fauna was derived from Indo-Pacific clades. Our phylogenetic results demonstrated greater concordance with geography than did previous phylogenies based on morphology. Time-stratifying the DEC reconstruction improved the fit and was highly consistent with paleo-ocean currents and paleogeography. Lastly, combining molecular phylogenetics with a rich and well-documented fossil record allowed us to test the accuracy and precision of biogeographic range reconstructions. PMID:26234273
Santoferrara, Luciana F; Grattepanche, Jean-David; Katz, Laura A; McManus, George B
Our knowledge on microbial biogeography depends on the way we define and study diversity. In contrast to most microbes, some protist lineages have conspicuous structures that allow comparisons of diversity concepts and measures-those based on molecules and those based on morphology. We analyzed a group of shell-bearing planktonic ciliates, the tintinnids, in a coast-to-ocean gradient using high-throughput sequencing and microscopy. First, we compared molecular operational taxonomic units (OTUs) and morphospecies in terms of assemblage composition, distribution and relationships with the environment. OTUs revealed potentially novel and rare taxa, while morphospecies showed clearer correlations with environmental factors, and both approaches coincided in supporting a coastal versus oceanic pattern. Second, we explored which processes influence assembly across the environmental gradient examined. Assemblage fluctuations were associated with significant distance-decay and changes in morphospecies size and prey proxies, thus suggesting niche partitioning as a key structuring mechanism. Our conclusion is that molecules and morphologies generally agreed, but they provided complementary data, the first revealing hidden diversity, and the latter making better connections between distribution patterns and ecological processes. This highlights the importance of linking genotypes and phenotypes (using multidisciplinary analyses and/or reliable databases of barcoded species), to understand the diversity, biogeography and ecological roles of microbes. PMID:26849313
Lim, Wee Loon; Wibowo, Antoni; Desa, Mohammad Ishak; Haron, Habibollah
The quadratic assignment problem (QAP) is an NP-hard combinatorial optimization problem with a wide variety of applications. Biogeography-based optimization (BBO), a relatively new optimization technique based on the biogeography concept, uses the idea of migration strategy of species to derive algorithm for solving optimization problems. It has been shown that BBO provides performance on a par with other optimization methods. A classical BBO algorithm employs the mutation operator as its diversification strategy. However, this process will often ruin the quality of solutions in QAP. In this paper, we propose a hybrid technique to overcome the weakness of classical BBO algorithm to solve QAP, by replacing the mutation operator with a tabu search procedure. Our experiments using the benchmark instances from QAPLIB show that the proposed hybrid method is able to find good solutions for them within reasonable computational times. Out of 61 benchmark instances tested, the proposed method is able to obtain the best known solutions for 57 of them. PMID:26819585
Lim, Wee Loon; Wibowo, Antoni; Desa, Mohammad Ishak; Haron, Habibollah
The quadratic assignment problem (QAP) is an NP-hard combinatorial optimization problem with a wide variety of applications. Biogeography-based optimization (BBO), a relatively new optimization technique based on the biogeography concept, uses the idea of migration strategy of species to derive algorithm for solving optimization problems. It has been shown that BBO provides performance on a par with other optimization methods. A classical BBO algorithm employs the mutation operator as its diversification strategy. However, this process will often ruin the quality of solutions in QAP. In this paper, we propose a hybrid technique to overcome the weakness of classical BBO algorithm to solve QAP, by replacing the mutation operator with a tabu search procedure. Our experiments using the benchmark instances from QAPLIB show that the proposed hybrid method is able to find good solutions for them within reasonable computational times. Out of 61 benchmark instances tested, the proposed method is able to obtain the best known solutions for 57 of them. PMID:26819585
Review of: The Biogeography of Fire in the San Bernardino Mountains of California--A Historical Study. By Richard A. Minnich. University of California Publications in Geography Volume 28, University of California Press, Berkeley. 120 pp. plus plates, soft cover.
Full Text Available Abstract Background Hydrocharitaceae is a fully aquatic monocot family, consists of 18 genera with approximately 120 species. The family includes both fresh and marine aquatics and exhibits great diversity in form and habit including annual and perennial life histories; submersed, partially submersed and floating leaf habits and linear to orbicular leaf shapes. The family has a cosmopolitan distribution and is well represented in the Tertiary fossil record in Europe. At present, the historical biogeography of the family is not well understood and the generic relationships remain controversial. In this study we investigated the phylogeny and biogeography of Hydrocharitaceae by integrating fossils and DNA sequences from eight genes. We also conducted ancestral state reconstruction for three morphological characters. Results Phylogenetic analyses produced a phylogeny with most branches strongly supported by bootstrap values greater than 95 and Bayesian posterior probability values of 1.0. Stratiotes is the first diverging lineage with the remaining genera in two clades, one clade consists of Lagarosiphon, Ottelia, Blyxa, Apalanthe, Elodea and Egeria; and the other consists of Hydrocharis-Limnobium, Thalassia, Enhalus, Halophila, Najas, Hydrilla, Vallisneria, Nechamandra and Maidenia. Biogeographic analyses (DIVA, Mesquite and divergence time estimates (BEAST resolved the most recent common ancestor of Hydrocharitaceae as being in Asia during the Late Cretaceous and Palaeocene (54.7-72.6 Ma. Dispersals (including long-distance dispersal and migrations through Tethys seaway and land bridges probably played major roles in the intercontinental distribution of this family. Ancestral state reconstruction suggested that in Hydrocharitaceae evolution of dioecy is bidirectional, viz., from dioecy to hermaphroditism, and from hermaphroditism to dioecy, and that the aerial-submerged leaf habit and short-linear leaf shape are the ancestral states. Conclusions
Mills, H. J.; Reese, B. K.
In this study, we take advantage of the isolation and scale of the deep marine subsurface to examine microbial biogeography. Unlike other environments, deep marine subsurface provides a unique opportunity to study biogeography across four dimensions. These samples are not only isolated by linear space on a global scale, but they are also temporally isolated by, in some cases, tens of millions of years. Through the support of multiple Integrated Ocean Drilling Program expeditions, we characterized the metabolically active fraction of the subsurface microbial community by targeting and sequencing 16S rRNA gene transcripts (RNA-based analysis). By characterizing the metabolically active fraction, we described lineages that were currently under selective environmental pressure and not relic lineages that may have become dormant or dead at some point in the past. This study was narrowed from the total diversity obtained to provide a detailed examination of the distribution and diversity of sulfate reducing bacteria (SRB); a functional group highly important to and ubiquitous in marine systems. The biogeochemical importance of this functional group, compounded with defined clades makes it a valuable and feasible target for a global biogeography study. SRB lineages from the deep subsurface were compared to contemporary lineages collected from multiple shallow sediment sites that had been extracted and sequenced using the same techniques. The SRB sequences acquired from our databases were clustered using 97% sequence similarity and analyzed using a suite of diversity and statistical tools. The geochemical conditions of the sediments sampled were considered when analyzing the resulting dendrograms and datasets. As hypothesized, lineages from the deep subsurface phylogenetically grouped together. However, similarities were detected to lineages from the shallow modern sediments, suggesting novel lineages may have evolved at a slow rate due to predicted lengthened life cycles
Borregaard, Michael; Amorim, Isabel; Borges, Paulo;
essentially non-equilibrium framework generating novel predictions for emergent diversity properties of oceanic islands and archipelagos. Its publication in 2008 coincided with, and spurred on, renewed attention to the dynamics of remote islands. We review progress, both in testing the GDM's predictions and...... in developing and enhancing ecological–evolutionary understanding of oceanic island systems through the lens of the GDM. In particular, we focus on four main themes: (i) macroecological tests using a space-for-time rationale; (ii) extensions of theory to islands following different patterns of......-native species diversity. We demonstrate the vitality of the field of island biogeography by identifying a range of potentially productive lines for future research....
Full Text Available This paper addresses a novel and efficient algorithm for solving optimization problem in image processing applications. Image enhancement (IE is one of the complex optimization problems in image processing. The main goal of this paper is to enhance color images such that the eminence of the image is more suitable than the original image from the perceptual viewpoint of human. Traditional methods require prior knowledge of the image to be enhanced, whereas the aim of the proposed biogeography based optimization (BBO enhanced with blended migration operator (BMO algorithm is to maximize the objective function in order to enhance the image contrast by maximizing the parameters like edge intensity, edge information, and entropy. Experimental results are compared with the current state-of-the-art approaches and indicate the superiority of the proposed technique in terms of subjective and objective evaluation.
Jian-Hua LI; Qiao-Ping XIANG
In order to develop better insights into biogeographic patterns of eastern Asian and North American disjunct plant genera, sequences of nuclear ribosomal DNA internal transcribed spacer (nr DNA ITS) region were used to estimate interspecific relationships of Thuja L. (Cupressaceae) and infer its biogeography based on the phylogeny. According to the phylogenetic analysis, two clades were recognized. The first clade included Thuja plicata D. Don (western North America) and T. koraiensis Nakai (northeastern Asia), and the second one contained T. occidentalis (Gord.) Carr. (Japan). The ancestral area of Thuja was inferred to be eastern Asia, and two dispersal events were responsible for the modern distribution of Thuja in North America. Both the North Atlantic land bridge and Bering land bridge were possible routes for the migration of ancestral populations to North America.
Hibbs, Douglas A; Olsson, Ola
The most important event in human economic history before the industrial revolution was the Neolithic transition from a nomadic hunter-gatherer lifestyle to sedentary agriculture, beginning approximately 10,000 years ago. The transition made possible the human population explosion, the rise of non-food-producing specialists, and the acceleration of technological progress that led eventually to the industrial revolution. But the transition occurred at different times in different regions of the world, with big consequences for the present-day economic conditions of populations indigenous to each region. In this article, we show that differences in biogeographic initial conditions and in geography largely account for the different timings of the Neolithic transition and, thereby, ultimately help account for the 100-fold differences among the prosperity of nations today. The effects of biogeography and geography on the wealth of nations are partly mediated by the quality of present-day institutions but also are partly independent of institutional quality. PMID:14985502
Full Text Available Faunistic and systematic studies on Crabronidae of Turkey are reviewed and the distribution and biogeography of the Turkish Crabronid wasp fauna is analyzed. In this study, 21 species and subspecies of 2 genera of Astatinae, 122 species and subspecies of 19 genera of Bembicinae, 72 species and subspecies of 3 genera of Philanthinae, 61 species and subspecies of 13 genera of Pempherdoninae, 2 species of 1 genus of Mellininae, 1 species of 1 genus of Dinetinae and 238 species and subspecies of 26 genera of Crabroninae are recorded. In total, 502 species and 15 subspecies belonging to 65 genera of Crabronidae are recorded from Turkey. Among them, 44 species and 6 subspecies comprising 9,7% of Turkish crabronids are endemic. Furthermore, the type localities of 69 species and 10 subspecies of Crabronidae are located in Turkey. Species composition, diversity and proportion of endemism varies considerably between the biogeographic subregions of the country.
Tewksbury, Joshua J; Manchego, Carlos; Haak, David C; Levey, Douglas J
The biogeography of pungency in three species of wild chili in the chaco and surrounding highland habitats of southeastern Bolivia is described. We report that Capsicum chacoense, C. baccatum, and C. eximium are polymorphic for production of capsaicin and its analogs, such that completely pungent and completely nonpungent individuals co-occur in some populations. In C. chacoense, the density of plants and the proportion of pungent plants increased with elevation. Above 900 m, all individuals in all populations except two were pungent; nonpungent individuals in at least one of the two polymorphic populations were likely a result of spreading by humans. The occurrence of pungent and nonpungent individuals in three species of ancestral Capsicum and the geographic variation of pungency within species suggest that production of capsaicin and its analogs entails both costs and benefits, which shift from one locality to another. Determining the selection pressures behind such shifts is necessary to understand the evolution of pungency in chilies. PMID:16572297
Benny K K Chan
Full Text Available The biogeography and ecology of the species of Chthamalus present on the west coast of America are described, using data from 51 localities from Alaska to Panama, together with their zonation on the shore with respect to that of other barnacles. The species present were C. dalli, Pilsbry 1916, C. fissus, Darwin, 1854, C. anisopoma Pilsbry 1916 and four species in the C. panamensis complex. The latter are C. panamensis Pilsbry, 1916, C. hedgecocki, Pitombo & Burton, 2007, C. alani nom. nov. (formerly C. southwardorum Pitombo & Burton, 2007 and C. newmani sp. nov.. These four species were initially separated by enzyme electrophoresis. They could only be partially separated by DNA bar coding but may be separated using morphological characters.
Full Text Available The taxonomic status and biogeography of the North American Raphia species is reviewed using adult morphology, larval host plants, geographic phenotypic variation, and variation of mtDNA COI barcode sequences. Lack of diagnostic morphological differences, combined with relatively low mtDNA barcode divergences and clinal phenotypic variation in key geographic regions indicate that the six previously recognized species of North American Raphia are best interpreted as parapatric subspecies. Raphia frater abrupta Grote, stat. n., R. f. coloradensis Putnam-Cramer, stat. r., R. f. piazzi Hill, stat. n., and R. f. elbea Smith, stat. n., are accordingly revised to subspecies of R. frater Grote. Type locality restrictions are provided for Raphia abrupta and Raphia frater and a neotype is designated for Raphia frater var. coloradensis.
Full Text Available The distribution and species assembly of Japanese Protura collected from forest soils were examined using published databases and statistical analysis. We used records from 3110 sites where 71 taxa were found. The species richness of Protura ranged from one to 16 species, and TWINSPAN analysis of regional populations indicated that the northern and southern regions could be separated into distinct groups. Three major species assemblages were identified by cluster analysis from points containing more than six species. Three groups reflected historical migration from northern and western linkages to the Asian continent. The northern assemblage showed a negative correlation to winter minimum temperature and the other two assemblages exhibited relationships to precipitation and temperature. Vegetation was not responsible for proturan distribution. These results suggest that the history of Protura invasion explains the biogeography of these soil-based, small arthropods and also that climate change will induce a shift in the distribution of species irrespective of changes in vegetation type.
Brown, M.; Dinsmore, J.J.
Species-area data from a study of marsh birds are used to test five predictions generated by the equilibrium theory of island biogeography. Three predictions are supported: we found a significant species-area relationship, a non-zero level of turnover, and a variance-mean ratio of 0.5. One prediction is rejected: the extinction rates were not greater on small islands. The results of one test are equivocal: the number of species on each island was not always the same. As Gilbert (1980) suggests, a strong species-area relationship alone does not validate the theory. The avian communities we studied were on habitat islands, not true islands, and underwent complete extinction annually. Thus caution must be used before applying the theory to these and other habitat islands.
Full Text Available The Galápagos giant tortoise is an icon of the unique, endemic biodiversity of Galápagos, but little is known of its parasitic fauna. We assessed the diversity of parasitic nematode communities and their spatial distributions within four wild tortoise populations comprising three species across three Galápagos islands, and consider their implication for Galápagos tortoise conservation programmes. Coprological examinations revealed nematode eggs to be common, with more than 80% of tortoises infected within each wild population. Faecal samples from tortoises within captive breeding centres on Santa Cruz, Isabela and San Cristobal islands also were examined. Five different nematode egg types were identified: oxyuroid, ascarid, trichurid and two types of strongyle. Sequencing of the 18S small-subunit ribosomal RNA gene from adult nematodes passed with faeces identified novel sequences indicative of rhabditid and ascaridid species. In the wild, the composition of nematode communities varied according to tortoise species, which co-varied with island, but nematode diversity and abundance were reduced or altered in captive-reared animals. Evolutionary and ecological factors are likely responsible for the variation in nematode distributions in the wild. This possible species/island-parasite co-evolution has not been considered previously for Galápagos tortoises. We recommend that conservation efforts, such as the current Galápagos tortoise captive breeding/rearing and release programme, be managed with respect to parasite biogeography and host-parasite co-evolutionary processes in addition to the biogeography of the host.
Chau, J. F.; Bouchillon, G.; Shor, L. M.
Microscopic organisms such as bacteria and protozoa are the engine that drives global biogeochemical processes: microbes fix carbon, produce oxygen, mediate nutrient cycling, and break down anthropogenic contaminants. In many habitats, the bacterial community structure and its net production is controlled in a top-down fashion by predation by protozoa. Despite their importance, many researchers have noted a significant gap in our understanding of their diversity, biogeography, and ecosystem function. We developed a microfluidic field sampling and analysis tool to study the biogeography and function of microbial eukaryotes. Microfluidic samplers were created to systematically target the morphology, function, and habitat of different microbial eukaryotes. Features such as channel dimensions, branching angles and radii of curvature were varied to allow organisms to be selected and captured based on cell size, shape, plasticity, and swimming or crawling modalities. We also developed genetic analysis protocols to extract and amplify DNA from a single trapped cell, allowing for molecular identification of trapped species. Results from freshwater sediment and water column deployments confirmed design efficiencies in trapping and concentrating protozoa based on biomass density, allowed for analysis of body plasticity and cell size, and also confirmed the viability of this technology for future real time monitoring of protozoa in aquatic ecosystems. This research offers a radical departure from existing approaches to study microbial eukaryotic communities in the field. Our novel methodology involving trapping, observation and recording of physical characteristics and genetic analysis of single cells allows comparison with bulk samples to place trapped microbes within a function- and habitat-specific context.
Goetze, Erica; Ohman, Mark D.
Species range information forms the empirical data of pelagic biogeography. Early descriptions of canonical zooplankton distributions in the Pacific Ocean were based, in part, on distributional data from the planktonic copepod family Eucalanidae. A large-scale molecular survey of this group, covering Atlantic, Pacific, and Indian Oceans (1295 individuals), increased the total diversity from 24 to 39 evolutionarily significant units (ESUs). New biogeographies are presented here for 18 lineages within 10 described species in the genera Subeucalanus, Pareucalanus, and Rhincalanus. Integration of molecular and morphological data on diversity and distribution resulted in three primary outcomes: (1) the morphological species was confirmed to be valid, and the biogeographic distribution remains largely unchanged from prior reports, (2) the species was found to contain multiple ESUs, each of which has a more restricted distribution than the parent taxon, and (3) the species was found to contain multiple ESUs, whose biogeographic distributions remain unclear. Subeucalanus subtenuis, S. mucronatus, S. subcrassus, Pareucalanus attenuatus, P. langae, and P. parki are all valid genetic and morphological species, and prior distribution records from Fleminger (1973) and Lang (1965) are confirmed to be accurate. New records in the western Indian Ocean extend the biogeographic range of S. subtenuis, S. mucronatus, S. subcrassus, and P. langae. Subeucalanus pileatus, P. sewelli, and R. rostrifrons, all species with Indo-Pacific or circumglobal distributions, consist of genetically divergent, allopatric populations that subdivide the original biogeographic range. Subeucalanus crassus and Rhincalanus nasutus are species complexes containing 4-8 genetically divergent lineages, whose distributions are inadequately characterized. Although results suggest more restricted pelagic habitats for some eucalanid species, those habitats have been previously described for other zooplanktonic taxa
Full Text Available The relevance and integration of scientific knowledge to conservation management of the locally popular and highly endemic butterfly genus Chrysoritis are investigated within the research fields of taxonomy and biogeography. The butterfly genus Chrysoritis contains at least 41 species endemic to South Africa. The taxonomy of Chrysoritis has reached a state where revisions could easily result in a plethora of names between “lumping and splitting”. In practice, the state of the taxonomy of these butterflies on species level may alter their conservation priority. The two most species rich species groups in Chrysoritis have different centres of endemism, however, a butterfly atlas becomes a necessity to reveal more about their biogeography. There is an absence of butterfly species lists in many of our National Parks and Nature Reserves. Legislation should facilitate rather than limit the valuable role of the amateur lepidopterist to add distribution records. In turn, the amateur lepidopterists should adapt and make an effort to explore unknown localities, apart from monitoring butterflies at their well-known localities. The red listing of localised butterflies in South Africa, including a number of Chrysoritis species, is in need of an urgent review in the light of the most recent IUCN categories. A species such as Chrysoritis dicksoni should be protected by law - but at its known localities. The scenario that real conservation action is only needed if the last known locality of a butterfly is threatened, should be abolished. A paradigm shift to conserve the metapopulations of the highly endemic Chrysoritis genus and not merely a few of its species as items that appear on lists, seems necessary.
Jiang, Wenjuan; Shi, Yunbo; Zhao, Wenjie; Wang, Xiangxin
The main part of the magnetic fluxgate sensor is the magnetic core, the hysteresis characteristic of which affects the performance of the sensor. When the fluxgate sensors are modelled for design purposes, an accurate model of hysteresis characteristic of the cores is necessary to achieve good agreement between modelled and experimental data. The Jiles-Atherton model is simple and can reflect the hysteresis properties of the magnetic material precisely, which makes it widely used in hysteresis modelling and simulation of ferromagnetic materials. However, in practice, it is difficult to determine the parameters accurately owing to the sensitivity of the parameters. In this paper, the Biogeography-Based Optimization (BBO) algorithm is applied to identify the Jiles-Atherton model parameters. To enhance the performances of the BBO algorithm such as global search capability, search accuracy and convergence rate, an improved Biogeography-Based Optimization (IBBO) algorithm is put forward by using Arnold map and mutation strategy of Differential Evolution (DE) algorithm. Simulation results show that IBBO algorithm is superior to Genetic Algorithm (GA), Particle Swarm Optimization (PSO) algorithm, Differential Evolution algorithm and BBO algorithm in identification accuracy and convergence rate. The IBBO algorithm is applied to identify Jiles-Atherton model parameters of selected permalloy. The simulation hysteresis loop is in high agreement with experimental data. Using permalloy as core of fluxgate probe, the simulation output is consistent with experimental output. The IBBO algorithm can identify the parameters of Jiles-Atherton model accurately, which provides a basis for the precise analysis and design of instruments and equipment with magnetic core. PMID:27347974
J Jacob Parnell
Full Text Available BACKGROUND: Horizontal gene transfer (HGT plays a major role in speciation and evolution of bacteria and archaea by controlling gene distribution within an environment. However, information that links HGT to a natural community using relevant population-genetics parameters and spatial considerations is scarce. The Great Salt Lake (Utah, USA provides an excellent model for studying HGT in the context of biogeography because it is a contiguous system with dispersal limitations due to a strong selective salinity gradient. We hypothesize that in spite of the barrier to phylogenetic dispersal, functional characteristics--in the form of HGT--expand beyond phylogenetic limitations due to selective pressure. METHODOLOGY AND RESULTS: To assay the functional genes and microorganisms throughout the GSL, we used a 16S rRNA oligonucleotide microarray (Phylochip and a functional gene array (GeoChip to measure biogeographic patterns of nine microbial communities. We found a significant difference in biogeography based on microarray analyses when comparing Sørensen similarity values for presence/absence of function and phylogeny (Student's t-test; p = 0.005. CONCLUSION AND SIGNIFICANCE: Biogeographic patterns exhibit behavior associated with horizontal gene transfer in that informational genes (16S rRNA have a lower similarity than functional genes, and functional similarity is positively correlated with lake-wide selective pressure. Specifically, high concentrations of chromium throughout GSL correspond to an average similarity of chromium resistance genes that is 22% higher than taxonomic similarity. This suggests active HGT may be measured at the population level in microbial communities and these biogeographic patterns may serve as a model to study bacteria adaptation and speciation.
Full Text Available Planktonic foraminifera are a major contributor to the deep carbonate-flux and the planktonic biomass of the global ocean. Their microfossil deposits form one of the richest databases for reconstructing paleoenvironments, particularly through changes in their taxonomic and shell composition. Using an empirically-based foraminifer model that incorporates three known major physiological drivers of foraminifer biogeography – temperature, food and light – we investigate (i the global redistribution of planktonic foraminifera under anthropogenic climate change, and (ii the alteration of the carbonate chemistry of foraminifer habitat with ocean acidification. The present-day and future (2090–2100 3-D distributions of foraminifera are simulated using temperature, plankton biomass, and light from an Earth system model forced with historical and a future (IPCC A2 high CO2 emission scenario. The broadscale patterns of present day foraminifer biogeography are well reproduced. Foraminifer abundance and diversity are projected to decrease in the tropics and subpolar regions and increase in the subtropics and around the poles. In the tropics, the geographical shifts are driven by temperature, while the vertical shifts are driven by both temperature and food availability. In the high-latitudes, vertical shifts are driven by food availability, while geographical shifts are driven by both food availability and temperature. Changes in the marine carbon cycle would be expected in response to (i the large-scale rearrangements in foraminifer abundance, and (ii the reduction of the carbonate concentration in the habitat range of planktonic foraminifers: from 10–30 μmol kg−1 in the polar/subpolar regions to 30–70 μmol kg−1 in the subtropical/tropical regions. High-latitude species are most vulnerable to anthropogenic change: their abundance and available habitat decrease and up to 10% of their habitat drops below the calcite saturation horizon.
Ivory, S.; Lézine, A. M.; Vincens, A.; Cohen, A. S.
African ecosystems are at great risk due to climate and land-use change. Despite the status of several of these regions as biodiversity hotspots, long-standing ideas about African ecology and biogeography have been unable to be tested until now due to lack of sufficiently long records. Here, we present the first long, continuous terrestrial record of vegetation from Lake Malawi, East Africa which goes back to the early Late Quaternary, permitting us to investigate changes in physiognomy and forest composition over many transitions. In this record, we observe eight phases of forest expansion and collapse. Although diversity is much greater during forest phases, composition varies little from phase to phase. Very high abundances of afromontane taxa suggest frequent widespread colonization of the lowlands by modern high elevation trees. Although there are clear successional stages within each forest such that turnover is great within a single phase, among forest samples between phases, there is little dissimilarity. Each forest phase is interrupted by rapid decline of arboreal taxa and expansion of semi-arid grasslands or woodlands whose composition varies greatly from phase to phase. The variable composition of the more open phases, all occurring during arid periods, is likely dynamically linked to thresholds in regional hydrology associated with lake level and moisture recycling within the watershed. This vegetation is unlike any found at Malawi today, with assemblages suggesting strong Somali-Masai affinities. Furthermore, nearly all semi-arid assemblages contain small abundances of forest taxa typically growing in areas with wetter edaphic conditions, suggesting that moist lowland gallery forests were present but restricted to waterways during exceptionally arid times. The waxing and waning of forests throughout this interval has important implications for early human biogeography across Africa as well as disturbance regimes that are crucial for the maintenance of
Roy, T.; Lombard, F.; Bopp, L.; Gehlen, M.
Planktonic Foraminifera are a major contributor to the deep carbonate flux and their microfossil deposits form one of the richest databases for reconstructing paleoenvironments, particularly through changes in their taxonomic and shell composition. Using an empirically based planktonic foraminifer model that incorporates three known major physiological drivers of their biogeography - temperature, food and light - we investigate (i) the global redistribution of planktonic Foraminifera under anthropogenic climate change and (ii) the alteration of the carbonate chemistry of foraminiferal habitat with ocean acidification. The present-day and future (2090-2100) 3-D distributions of Foraminifera are simulated using temperature, plankton biomass and light from an Earth system model forced with a historical and a future (IPCC A2) high CO2 emission scenario. Foraminiferal abundance and diversity are projected to decrease in the tropics and subpolar regions and increase in the subtropics and around the poles. Temperature is the dominant control on the future change in the biogeography of Foraminifera. Yet food availability acts to either reinforce or counteract the temperature-driven changes. In the tropics and subtropics the largely temperature-driven shift to depth is enhanced by the increased concentration of phytoplankton at depth. In the higher latitudes the food-driven response partly offsets the temperature-driven reduction both in the subsurface and across large geographical regions. The large-scale rearrangements in foraminiferal abundance and the reduction in the carbonate ion concentrations in the habitat range of planktonic foraminifers - from 10-30 μmol kg-1 in their polar and subpolar habitats to 30-70 μmol kg-1 in their subtropical and tropical habitats - would be expected to lead to changes in the marine carbonate flux. High-latitude species are most vulnerable to anthropogenic change: their abundance and available habitat decrease and up to 10% of the
Zhang, Binglin; Wu, Xiukun; Zhang, Gaosen; Li, Shuyan; Zhang, Wei; Chen, Ximing; Sun, Likun; Zhang, Baogui; Liu, Guangxiu; Chen, Tuo
Glacier forelands, where the initially exposed area is unvegetated with minimal human influence, are an ideal place for research on the distributions and biogeography of microbial communities. Actinobacteria produce many bioactive substances and have important roles in soil development and biogeochemical cycling. However, little is known about the distribution and biogeography of Actinobacteria in glacier forelands. Therefore, we investigated the patterns of diversity and the biogeography of actinobacterial communities of the inhabited forefields of 5 glaciers in China. Of the bacteria, the mean relative abundance of Actinobacteria was 13.1%, and 6 classes were identified in the phylum Actinobacteria. The dominant class was Actinobacteria (57%), which was followed in abundance by Acidimicrobiia (19%) and Thermoleophilia (19%). When combined, the relative abundance of the other three classes, the MB-A2-108, Nitriliruptoria and Rubrobacteria, was only 2.4%. A biogeographic pattern in the forelands of the 5 glaciers in China was not detected for actinobacterial communities. Compared with 7 other actinobacterial communities found in the forelands of glaciers globally, those in the Southern Hemisphere were significantly different from those in the Northern Hemisphere. Moreover, the communities were significantly different on the separate continents of the Northern Hemisphere. The dissimilarity of the actinobacterial communities increased with geographic distance (r = 0.428, p = 0.0003). Because of environmental factors, the effect of geography was clear when the distance exceeded a certain continent-level threshold. With the analysis of indicator species, we found that each genus had a geographic characteristic, which could explain why the communities with greater diversity were more strongly affected by biogeography.
Zi-wu REN; Zhen-hua WANG; Li-ning SUN
The redundant humanoid manipulator has characteristics of multiple degrees of freedom and complex joint structure, and it is not easy to obtain its inverse kinematics solution. The inverse kinematics problem of a humanoid manipulator can be formulated as an equivalent minimization problem, and thus it can be solved using some numerical optimization methods. Biogeography-based optimization (BBO) is a new biogeography inspired optimization algorithm, and it can be adopted to solve the inverse kinematics problem of a humanoid manipulator. The standard BBO algorithm that uses traditional migration and mutation operators suffers from slow convergence and prematurity. A hybrid biogeography-based optimization (HBBO) algorithm, which is based on BBO and differential evolution (DE), is presented. In this hybrid algorithm, new habitats in the ecosystem are produced through a hybrid migration operator, that is, the BBO migration strategy and DE/best/1/bin differential strategy, to alleviate slow convergence at the later evolution stage of the algorithm. In addition, a Gaussian mutation operator is adopted to enhance the exploration ability and improve the diversity of the population. Based on these, an 8-DOF (degree of freedom) redundant humanoid manipulator is employed as an example. The end-effector error (position and orientation) and the‘away limitation level’ value of the 8-DOF humanoid manipulator constitute the fi tness function of HBBO. The proposed HBBO algorithm has been used to solve the inverse kinematics problem of the 8-DOF redundant humanoid manipulator. Numerical simulation results demonstrate the effectiveness of this method.
Highlights: • Solar cell and PEM fuel cell parameter estimations are investigated in the paper. • A new biogeography-based method (BBO-M) is proposed for cell parameter estimations. • In BBO-M, two mutation operators are designed to enhance optimization performance. • BBO-M provides a competitive alternative in cell parameter estimation problems. - Abstract: Mathematical models are useful tools for simulation, evaluation, optimal operation and control of solar cells and proton exchange membrane fuel cells (PEMFCs). To identify the model parameters of these two type of cells efficiently, a biogeography-based optimization algorithm with mutation strategies (BBO-M) is proposed. The BBO-M uses the structure of biogeography-based optimization algorithm (BBO), and both the mutation motivated from the differential evolution (DE) algorithm and the chaos theory are incorporated into the BBO structure for improving the global searching capability of the algorithm. Numerical experiments have been conducted on ten benchmark functions with 50 dimensions, and the results show that BBO-M can produce solutions of high quality and has fast convergence rate. Then, the proposed BBO-M is applied to the model parameter estimation of the two type of cells. The experimental results clearly demonstrate the power of the proposed BBO-M in estimating model parameters of both solar and fuel cells
Highlights: • A modified version of the BBO was proposed. • A novel method for interval type-2 FLC design tuned by MBBO was proposed. • The performance of the ETRR-2 was improved by using IT2FLC tuned by MBBO. -- Abstract: Power stabilization is a critical issue in nuclear reactors. The conventional proportional derivative (PD) controller is currently used in the Egyptian second testing research reactor (ETRR-2). In this paper, we propose a modified biogeography-based optimization (MBBO) algorithm to design the interval type-2 fuzzy logic controller (IT2FLC) to improve the performance of the Egyptian second testing research reactor (ETRR-2). Biogeography-based optimization (BBO) is a novel evolutionary algorithm that is based on the mathematical models of biogeography. Biogeography is the study of the geographical distribution of biological organisms. In the BBO model, problem solutions are represented as islands, and the sharing of features between solutions is represented as immigration and emigration between the islands. A modified version of the BBO is applied to design the IT2FLC to get the optimal parameters of the membership functions of the controller. We test the optimal IT2FLC obtained by modified biogeography-based optimization (MBBO) using the integral square error (ISE) and is compared with the currently used PD controller
Sayed, M.M., E-mail: M.M.Sayed@ieee.org; Saad, M.S.; Emara, H.M.; Abou El-Zahab, E.E.
Highlights: • A modified version of the BBO was proposed. • A novel method for interval type-2 FLC design tuned by MBBO was proposed. • The performance of the ETRR-2 was improved by using IT2FLC tuned by MBBO. -- Abstract: Power stabilization is a critical issue in nuclear reactors. The conventional proportional derivative (PD) controller is currently used in the Egyptian second testing research reactor (ETRR-2). In this paper, we propose a modified biogeography-based optimization (MBBO) algorithm to design the interval type-2 fuzzy logic controller (IT2FLC) to improve the performance of the Egyptian second testing research reactor (ETRR-2). Biogeography-based optimization (BBO) is a novel evolutionary algorithm that is based on the mathematical models of biogeography. Biogeography is the study of the geographical distribution of biological organisms. In the BBO model, problem solutions are represented as islands, and the sharing of features between solutions is represented as immigration and emigration between the islands. A modified version of the BBO is applied to design the IT2FLC to get the optimal parameters of the membership functions of the controller. We test the optimal IT2FLC obtained by modified biogeography-based optimization (MBBO) using the integral square error (ISE) and is compared with the currently used PD controller.
Howard, E. A.; Coe, M. T.; Foley, J. A.; Costa, M. H.
Amazonian ecosystems provide key ecosystem services, such as regulating the amount and timing of water and carbon flows through the Amazon Basin. Land use in these ecosystems affects regional water balance, which in turn affects biogeography of aquatic ecosystems, including wetlands and floodplains. We combined a hydrological model (Terrestrial Hydrology Model with Biogeochemistry, THMB), remote sensing observations (Hess et al. 2003), and empirical data to identify the distribution of aquatic biogeographic types throughout the central Amazon basin over time. We explored how future land-use scenarios for the Amazon Basin through 2030 (Soares-Filho et al. 2004) would modify the spatial and temporal patterns of aquatic ecosystems as compared to a baseline of natural potential vegetation cover under historical climate variability for the 20th century. We calibrated monthly simulation results with remotely sensed observations of flooded area and extent of different wetland categories for high and low water periods over a 1.7 million sq. km region of the central Amazon. Two additional dimensions of floodplain biogeography (river size and color) were added to provide insight into the geographic distribution of key ecosystem types and their flooding seasonality. For historical conditions, the model results reproduced regional differences in seasonal flood extent and timing north and south of the Amazon mainstem, reflecting the dominant climatic regimes. Black-water streams and medium-sized rivers, followed by large white-water rivers, were the most extensive types across the study region. However much of the black water was in areas likely to be influenced by white-water rivers while flooded. The monthly extent of flooded areas dominated by woody vegetation was consistently more strongly seasonal than non-woody areas. Also, the extent of flooding in muddy and semi-muddy rivers and floodplains tended to be more highly seasonal than in black- and clear-water areas. We
Li, Qin-Qin; Zhou, Song-Dong; Huang, De-Qing; He, Xing-Jin; Wei, Xian-Qin
A primary aim of historical biogeography is to identify the causal factors or processes that have shaped the composition and distribution of biotas over time. Another is to infer the evolution of geographic ranges of species and clades in a phylogenetic context. To this end, historical biogeography addresses important questions such as: Where were ancestors distributed? Where did lineages originate? Which processes cause geographic ranges to evolve through time? Allium subgenus Anguinum comprises approximately twelve taxa with a disjunct distribution in the high mountains from south-western Europe to eastern Asia and in northeastern North America. Although both the systematic position and the geographical limits of Anguinum have been identified, to date no molecular systematic study has been performed utilizing a comprehensive sampling of these species. With an emphasis on the Anguinum eastern Asian geographical group, the goals of the present study were: (i) to infer species-level phylogenetic relationships within Anguinum, (ii) to assess molecular divergence and estimated the times of the major splits in Anguinum and (iii) to trace the biogeographic history of the subgenus. Four DNA sequences (ITS, matK, trnH-psbA, rps16) were used to reconstruct the phylogeny of Allium subgen. Anguinum RbcL sequences were used to estimate divergences time for Allium, and sequences of ITS were used to estimate the divergence times for Anguinum and its main lineages and to provide implications for the evolutionary history of the subgenus. Phylogenetic analyses for all Allium corroborate that Anguinum is monophyletic and indicate that Anguinum is composed of two sister groups: one with a Eurasian-American distribution, and the other restricted to eastern Asia. In the eastern Asian geographical group, incongruence between gene trees and morphology-based taxonomies was recovered as was incongruence between data from plastid and nuclear sequences. This incongruence is likely due to
T S Jeyali Laseetha; R Sukanesh
In this paper, we propose biogeography based optimization technique, with linear and sinusoidal migration models and simplified biogeography based optimization (S-BBO), for uniformly spaced linear antenna array synthesis to maximize the reduction of side lobe level (SLL). This paper explores biogeography theory. It generalizes two migration models in BBO namely, linear migration model and sinusoidal migration model. The performance of SLL reduction in ULA is investigated. Our performance study shows that among the two, sinusoidal migration model is a promising candidate for optimization. In our work, simplified – BBO algorithmis also deployed. This determines an optimum set value for amplitude excitations of antenna array elements that generate a radiation pattern with maximum side lobe level reduction. Our detailed investigation also shows that sinusoidal migration model of BBO performs better compared to the other evolutionary algorithms discussed in this paper.
Fujioka, Ei; Vanden Berghe, Edward; Donnelly, Ben; Castillo, Julio; Cleary, Jesse; Holmes, Chris; McKnight, Sean; Halpin, patrick
Across many scientific domains, the ability to aggregate disparate datasets enables more meaningful global analyses. Within marine biology, the Census of Marine Life served as the catalyst for such a global data aggregation effort. Under the Census framework, the Ocean Biogeographic Information System was established to coordinate an unprecedented aggregation of global marine biogeography data. The OBIS data system now contains 31.3 million observations, freely accessible through a geospatial portal. The challenges of storing, querying, disseminating, and mapping a global data collection of this complexity and magnitude are significant. In the face of declining performance and expanding feature requests, a redevelopment of the OBIS data system was undertaken. Following an Open Source philosophy, the OBIS technology stack was rebuilt using PostgreSQL, PostGIS, GeoServer and OpenLayers. This approach has markedly improved the performance and online user experience while maintaining a standards-compliant and interoperable framework. Due to the distributed nature of the project and increasing needs for storage, scalability and deployment flexibility, the entire hardware and software stack was built on a Cloud Computing environment. The flexibility of the platform, combined with the power of the application stack, enabled rapid re-development of the OBIS infrastructure, and ensured complete standards-compliance.
Full Text Available Biogeography and metacommunity ecology provide two different perspectives on species diversity. Both are spatial in nature but their spatial scales do not necessarily match. With recent boom of metacommunity studies, we see an increasing need for clear discrimination of spatial scales relevant for both perspectives. This discrimination is a necessary prerequisite for improved understanding of ecological phenomena across scales. Here we provide a case study to illustrate some spatial scale-dependent concepts in recent metacommunity studies and identify potential pitfalls. We presented here the diversity patterns of Neotropical lepidopterans and spiders viewed both from metacommunity and biogeographical perspectives. Specifically, we investigated how the relative importance of niche- and dispersal-based processes for community assembly change at two spatial scales: metacommunity scale, i.e. within a locality, and biogeographical scale, i.e. among localities widely scattered along a macroclimatic gradient. As expected, niche-based processes dominated the community assembly at metacommunity scale, while dispersal-based processes played a major role at biogeographical scale for both taxonomical groups. However, we also observed small but significant spatial effects at metacommunity scale and environmental effects at biogeographical scale. We also observed differences in diversity patterns between the two taxonomical groups corresponding to differences in their dispersal modes. Our results thus support the idea of continuity of processes interactively shaping diversity patterns across scales and emphasize the necessity of integration of metacommunity and biogeographical perspectives.
Jordal, Bjarte H
Platypodinae is a peculiar weevil subfamily of species that cultivate fungi in tunnels excavated in dead wood. Their geographical distribution is generally restricted, with genera confined to a single continent or large island, which provides a useful system for biogeographical research. This study establishes the first detailed molecular phylogeny of the group, with the aim of testing hypotheses on classification, diversification, and biogeography. A phylogeny was reconstructed based on 3648 nucleotides from COI, EF-1α, CAD, ArgK, and 28S. Tree topology was well resolved and indicated a strong correlation with geography, more so than predicted by previous morphology-based classifications. Tesserocerini was paraphyletic, with Notoplatypus as the sister group to a clade consisting of three main lineages of Tesserocerini and the recently evolved Platypodini. Austroplatypus formed the sister group to all remaining Platypodini and hence confirmed its separate status from Platypus. The Indo-Australian genera of Platypodini were strikingly paraphyletic, suggesting that the taxonomy of this tribe needs careful revision. Ancestral-area reconstructions in Lagrange and S-DIVA were ambiguous for nodes roughly older than 80 Ma. More recent events were firmly assessed and involved post-Gondwanan long-distance dispersal. The Neotropics was colonized three times, all from the Afrotropical region, with the latest event less than 25 Ma that included the ancestor of all Neotropical Platypodini. PMID:26190520
Rashid, A; Kim, S; Liu, D; Kim, K Y
Dynamic electrical impedance tomography-based image reconstruction using conventional algorithms such as the extended Kalman filter often exhibits inferior performance due to the presence of measurement noise, the inherent ill-posed nature of the problem and its critical dependence on the selection of the initial guess as well as the state evolution model. Moreover, many of these conventional algorithms require the calculation of a Jacobian matrix. This paper proposes a dynamic oppositional biogeography-based optimization (OBBO) technique to estimate the shape, size and location of the non-stationary region boundaries, expressed as coefficients of truncated Fourier series, inside an object domain using electrical impedance tomography. The conductivity of the object domain is assumed to be known a priori. Dynamic OBBO is a novel addition to the family of dynamic evolutionary algorithms. Moreover, it is the first such study on the application of dynamic evolutionary algorithms for dynamic electrical impedance tomography-based image reconstruction. The performance of the algorithm is tested through numerical simulations and experimental study and is compared with state-of-the-art gradient-based extended Kalman filter. The dynamic OBBO is shown to be far superior compared to the extended Kalman filter. It is found to be robust to measurement noise as well as the initial guess, and does not rely on a priori knowledge of the state evolution model. PMID:27203482
Kornilios, P; Giokas, S; Lymberakis, P; Sindaco, R
The majority of the family Typhlopidae occurs in the Neotropic, Australasian, Indo-Malayan and Afrotropic ecoregions. They show a restricted distribution in the western Palearctic, where they include few native species, i.e. Rhinotyphlops simoni, R. episcopus and Typhlops vermicularis. A unique species among typhlopids is T. socotranus, found in Socotra, one of the most endemic-rich archipelagoes. In this study we determine the phylogenetic position of the above mentioned species and discuss their systematics, origin and biogeography. For this purpose we use three protein-coding nuclear markers (AMEL-amelogenin, BDNF-brain-derived neurotrophic factor and NT3-neurotrophin 3) to construct a time-calibrated phylogeny of the family Typhlopidae. Our results show that T. socotranus is a sister-species to T. vermicularis, while R. simoni and R. episcopus are sister-species to each other and are found within the African clade of the family, although they are geographically distributed in west Asia. Additionally we discuss several hypotheses on their origin, as well as the occurence of typhlopids in Eurasia. PMID:23523862
Reynolds, R Graham; Niemiller, Matthew L; Hedges, S Blair; Dornburg, Alex; Puente-Rolón, Alberto R; Revell, Liam J
The evolutionary and biogeographic history of West Indian boid snakes (Epicrates), a group of nine species and 14 subspecies, was once thought to be well understood; however, new research has indicated that we are missing a clear understanding of the evolutionary relationships of this group. Here, we present the first multilocus, species-tree based analyses of the evolutionary relationships, divergence times, and historical biogeography of this clade with data from 10 genes and 6256 bp. We find evidence for a single colonization of the Caribbean from mainland South America in the Oligocene or early Miocene, followed by a radiation throughout the Greater Antilles and Bahamas. These findings support the previous suggestion that Epicrates sensu lato Wagler is paraphyletic with respect to the anacondas (Eunectes Wagler), and hence we restrict Epicrates to the mainland clade and use the available name Chilabothrus Duméril and Bibron for the West Indian clade. Our results suggest some diversification occurred within island banks, though most species divergence events seem to have occurred in allopatry. We also find evidence for a remarkable diversification within the Bahamian archipelago suggesting that the recognition of another Bahamian endemic species C. strigilatus is warranted. PMID:23669009
Full Text Available Swarm Intelligence techniques expedite the configuration and collimation of the remarkable ability of group members to reason and learn in an environment of contingency and corrigendum from their peers by sharing information. This paper introduces a novel approach of fusion of two intelligent techniques generally to augment the performance of a single intelligent technique by means of information sharing. Biogeography-based optimization (BBO is a recently developed heuristic algorithm, which proves to be a strong entrant in swarm intelligence with the encouraging and consistent performance. But, as BBO lacks inbuilt property of clustering, its behavior can be replaced with the honey bees of artificial bee colony (ABC, a new swarm intelligent technique. These two methods can be combined to create a new method which is easy to implement and gives more optimized results than the results when BBO is used. We have successfully applied this fusion of techniques for classifying diversified land cover areas in a multispectral remote sensing satellite image. The results illustrate that the proposed approach is very efficient than BBO and highly accurate land cover features can be extracted by using this approach.
Coleman-Derr, Devin; Desgarennes, Damaris; Fonseca-Garcia, Citlali; Gross, Stephen; Clingenpeel, Scott; Woyke, Tanja; North, Gretchen; Visel, Axel; Partida-Martinez, Laila P; Tringe, Susannah G
Desert plants are hypothesized to survive the environmental stress inherent to these regions in part thanks to symbioses with microorganisms, and yet these microbial species, the communities they form, and the forces that influence them are poorly understood. Here we report the first comprehensive investigation of the microbial communities associated with species of Agave, which are native to semiarid and arid regions of Central and North America and are emerging as biofuel feedstocks. We examined prokaryotic and fungal communities in the rhizosphere, phyllosphere, leaf and root endosphere, as well as proximal and distal soil samples from cultivated and native agaves, through Illumina amplicon sequencing. Phylogenetic profiling revealed that the composition of prokaryotic communities was primarily determined by the plant compartment, whereas the composition of fungal communities was mainly influenced by the biogeography of the host species. Cultivated A. tequilana exhibited lower levels of prokaryotic diversity compared with native agaves, although no differences in microbial diversity were found in the endosphere. Agaves shared core prokaryotic and fungal taxa known to promote plant growth and confer tolerance to abiotic stress, which suggests common principles underpinning Agave-microbe interactions. PMID:26467257
Salerno, Jennifer L; Bowen, Brian W; Rappé, Michael S
Factors driving the distribution of marine microorganisms are widely debated and poorly understood. Recent studies show that free-living marine microbes exhibit geographical patterns indicative of limited dispersal. In contrast, host-associated microbes face a different set of dispersal challenges, and hosts may function as habitat 'islands' for resident microbial populations. Here, we examine the biogeographical distributions of planktonic and adjacent coral-associated bacterial communities across the Hawaiian Archipelago, Johnston Atoll (∼1400 km southwest of Hawaii) and American Samoa in the Pacific Ocean and investigate the potential underlying processes driving observed patterns. Statistical analyses of bacterial community structure, determined using a small-subunit ribosomal RNA gene-based approach, showed that bacterioplankton and coral-associated bacterial communities were distinct, and correlated with geographical distance between sites. In addition, biogeographical patterns of bacterial associates paralleled those of their host coral Porites lobata, highlighting the specificity of these associations and the impact that host dispersal may have on bacterial biogeography. Planktonic and coral-associated bacterial communities from distant Johnston Atoll were shown to be connected with communities from the center of the Hawaiian Archipelago, a pattern previously observed in fish and invertebrates. No significant correlations were detected with habitat type, temperature or depth. However, non-distance-based geographical groupings were detected, indicating that, in addition to dispersal, unidentified environmental factors also affected the distributions of bacterial communities investigated here. PMID:27222221
Sanmartín, Isabel; Meseguer, Andrea S
Global climate change and its impact on biodiversity levels have made extinction a relevant topic in biological research. Yet, until recently, extinction has received less attention in macroevolutionary studies than speciation; the reason is the difficulty to infer an event that actually eliminates rather than creates new taxa. For example, in biogeography, extinction has often been seen as noise, introducing homoplasy in biogeographic relationships, rather than a pattern-generating process. The molecular revolution and the possibility to integrate time into phylogenetic reconstructions have allowed studying extinction under different perspectives. Here, we review phylogenetic (temporal) and biogeographic (spatial) approaches to the inference of extinction and the challenges this process poses for reconstructing evolutionary history. Specifically, we focus on the problem of discriminating between alternative high extinction scenarios using time trees with only extant taxa, and on the confounding effect introduced by asymmetric spatial extinction - different rates of extinction across areas - in biogeographic inference. Finally, we identify the most promising avenues of research in both fields, which include the integration of additional sources of evidence such as the fossil record or environmental information in birth-death models and biogeographic reconstructions, the development of new models that tie extinction rates to phenotypic or environmental variation, or the implementation within a Bayesian framework of parametric non-stationary biogeographic models. PMID:27047538
Full Text Available Considering that common subsynchronous resonance controllers cannot adapt to the characteristics of the time-varying and nonlinear behavior of a power system, the cosine migration model, the improved migration operator, and the mutative scale of chaos and Cauchy mutation strategy are introduced into an improved biogeography-based optimization (IBBO algorithm in order to design an optimal subsynchronous damping controller based on the mechanism of suppressing SSR by static var compensator (SVC. The effectiveness of the improved controller is verified by eigenvalue analysis and electromagnetic simulations. The simulation results of Jinjie plant indicate that the subsynchronous damping controller optimized by the IBBO algorithm can remarkably improve the damping of torsional modes and thus effectively depress SSR, and ensure the safety and stability of units and power grid operation. Moreover, the IBBO algorithm has the merits of a faster searching speed and higher searching accuracy in seeking the optimal control parameters over traditional algorithms, such as BBO algorithm, PSO algorithm, and GA algorithm.
Niño-García, Juan Pablo; Ruiz-González, Clara; Del Giorgio, Paul A
Disentangling the mechanisms shaping bacterioplankton communities across freshwater ecosystems requires considering a hydrologic dimension that can influence both dispersal and local sorting, but how the environment and hydrology interact to shape the biogeography of freshwater bacterioplankton over large spatial scales remains unexplored. Using Illumina sequencing of the 16S ribosomal RNA gene, we investigate the large-scale spatial patterns of bacterioplankton across 386 freshwater systems from seven distinct regions in boreal Québec. We show that both hydrology and local water chemistry (mostly pH) interact to shape a sequential structuring of communities from highly diverse assemblages in headwater streams toward larger rivers and lakes dominated by fewer taxa. Increases in water residence time along the hydrologic continuum were accompanied by major losses of bacterial richness and by an increased differentiation of communities driven by local conditions (pH and other related variables). This suggests that hydrology and network position modulate the relative role of environmental sorting and mass effects on community assembly by determining both the time frame for bacterial growth and the composition of the immigrant pool. The apparent low dispersal limitation (that is, the lack of influence of geographic distance on the spatial patterns observed at the taxonomic resolution used) suggests that these boreal bacterioplankton communities derive from a shared bacterial pool that enters the networks through the smallest streams, largely dominated by mass effects, and that is increasingly subjected to local sorting of species during transit along the hydrologic continuum. PMID:26849312
Wang, Li; Cao, Ying; Wang, En Tao; Qiao, Ya Juan; Jiao, Shuo; Liu, Zhen Shan; Zhao, Liang; Wei, Ge Hong
The biodiversity and biogeography of rhizobia associated with bean in Shaanxi Province were investigated. A total of 194 bacterial isolates from bean nodules collected from 13 sampling sites were characterized based on phylogenetic analyses of the 16S rRNA gene, the housekeeping genes recA, glnII and atpD, and the symbiotic genes nodC and nifH. Fifteen genospecies belonging to the genera Rhizobium, Agrobacterium, Ensifer, Bradyrhizobium and Ochrobactrum were defined among the isolates, with Rhizobium sp. II, Agrobacterium sp. II, E. fredii and R. phaseoli being the dominant groups. Four symbiotic gene lineages corresponding to Rhizobium sp. I, Rhizobium sp. II, R. phaseoli and B. liaoningense were detected in the nodC and nifH sequence analyses, indicating different origins for the symbiotic genes and their co-evolution with the chromosome of the bacteria. Moreover, the Ensifer isolates harbored symbiotic genes closely related to bean-nodulating Pararhizobium giardinii, indicating possible lateral gene transfer from Rhizobium to Ensifer. Correlation of rhizobial community composition with moisture, temperature, intercropping, soil features and nutrients were detected. All the results demonstrated a great diversity of bean rhizobia in Shaanxi that might be due to the adaptable evolution of the bean-nodulating rhizobia subjected to the diverse ecological conditions in the area. PMID:26966063
Yan Li; Yan Kong; Zhe Zhang; Yanqiang Yin; Bin Liu; Guanghui Lv; Xiyong Wang
The genus Alyssum consists of about 195 species native to Europe, Asia and northern Africa. All species were assigned to six sections. Previous molecular phylogeny studies indicate that Alyssum is polyphyletic. However, the divergence time and dispersal of the genus are not well studied. In this study, the phylogenetic relationships within the genus Alyssum were studied with nrDNA ITS sequences obtained from five sections. The divergence time was estimated by fossil calibration and the biogeography was examined by spread analysis. The phylogeny indicated two main lineages: lineage 1 includes the section of Alyssum, Gamosepalum and Psilonema; lineage 2 includes the section of Odontarrhena, Meniocus and Clypeola. The phylogenetic relationship was not congruent with the previous sectional classifications. The age of Alyssum was dated to the upper Miocene. Molecular data suggested the diversification of Alyssum in Mediterranean areas and wide-ranging distribution such as North Africa, eastward into Central Asia and immigration into North America. Climatic aridification and arid/semiarid areas established in the Pliocene/Pleistocene could have provided favourable conditions for the migration and diversification of Alyssum.
Maekawa, Kiyoto; Matsumoto, Tadao
We investigated mitochondrial COII gene sequences of Japanese wood-feeding cockroaches (Salganea spp. and Panesthia angustipennis) in detail to investigate their biogeography. The transition (TI) numbers between each genus north and south of the Tokara Strait, which is a border of the Oriental and the Palaearctic faunal regions, were almost same, but the transversion (TV) numbers were much lower in Panesthia compared with Salganea. These tendencies suggest that multiple substitutions of TIs occurred between certain pairs of Salganea taxa and that the genera must have entered to the north of the Tokara Strait at different times. Phylogenetic relationships and estimated divergence times using TVs divergences suggest that Salganea species and Panesthia taxa north and south of the Tokara Strait were diverged from each other during the latter half of the Miocene and from the late Pliocene to the early Pleistocene, respectively. These two periods are nearly consistent with the two land expanding times in the Ryukyu Islands supported by the recent palaeogeographical hypotheses. PMID:12679080
Waters, Jonathan M.; Wallis, Graham P.; Burridge, Christopher P.; Craw, Dave
Geological processes are hypothesised to strongly affect species distributions. In particular, a combination of geological and biological data has suggested that tectonic processes can drive vicariant isolation and speciation in freshwater-limited taxa. Here we synthesise geological and biological evidence to demonstrate a composite geological and biological history for New Zealand's 290-km long Taieri River. Specifically, we assess evidence from structural geology and petrology, combined with phylogenetic and biogeographic analysis of galaxiid fishes, to show that the modern Taieri River was formed via capture of the ancestral Kye Burn during the mid-late Quaternary. Molecular dating analyses support a late-Quaternary timeframe for the geologically-mediated divergence between formerly-connected sister taxa Galaxias depressiceps and G. 'teviot'. Fish biogeography lends further support to the geological hypothesis, as there is a substantial biogeographic disjunction between the lower- (ancestral) and upper (captured) portions of the Taieri River. Geological and biological data are assessed independently yet yield consilient patterns and timeframes for the evolutionary events inferred. Broadly, this study highlights the interplay between physical and biological processes in a geologically dynamic setting.
Miller, Dane M.; Miller, Ian M.; Jackson, Stephen T.
Pleistocene biogeography of conifer species is poorly known in much of western North America. We conducted morphological studies on 201 conifer cones and cone fragments recovered from Pleistocene sediments at the Ziegler Reservoir fossil site (2705 m) near Snowmass Village, Colorado. The basin, formed ~ 155-130 ka, contains fossil-bearing lacustrine, palustrine, and colluvial sediments spanning approximately 85 ka. Using a suite of morphological characters, particularly cone-scale bracts, we differentiated species of Abies, Picea, and Pseudotsuga. All fossil Abies specimens were assignable based on bract morphology to Abies concolor, which is currently absent from central Colorado (nearest populations are 160 km southwest of the site). A. concolor occurs only in sediments of MIS 5d and 5c. Pseudotsuga menziesii and Picea engelmannii cones occurred in sediments corresponding to MIS 5e, 5d, 5c, and 5a. A fourth conifer species, occurring in sediments of MIS 5e, 5d, 5c, and 5a, is difficult to assign to any extant species. Bract morphology is similar to Picea pungens, which grows near the site today, but scale morphology is unlike P. pungens. These fossils may represent ancestral P. pungens, an extinct variant, or an extinct sister species.
Monier, Adam; Worden, Alexandra Z; Richards, Thomas A
High-throughput diversity amplicon sequencing of marine microbial samples has revealed that members of the Mamiellophyceae lineage are successful phytoplankton in many oceanic habitats. Indeed, these eukaryotic green algae can dominate the picoplanktonic biomass, however, given the broad expanses of the oceans, their geographical distributions and the phylogenetic diversity of some groups remain poorly characterized. As these algae play a foundational role in marine food webs, it is crucial to assess their global distribution in order to better predict potential changes in abundance and community structure. To this end, we analyzed the V9-18S small subunit rDNA sequences deposited from the Tara Oceans expedition to evaluate the diversity and biogeography of these phytoplankton. Our results show that the phylogenetic composition of Mamiellophyceae communities is in part determined by geographical provenance, and do not appear to be influenced - in the samples recovered - by water depth, at least at the resolution possible with the V9-18S. Phylogenetic classification of Mamiellophyceae sequences revealed that the Dolichomastigales order encompasses more sequence diversity than other orders in this lineage. These results indicate that a large fraction of the Mamiellophyceae diversity has been hitherto overlooked, likely because of a combination of size fraction, sequencing and geographical limitations. PMID:26929141
Full Text Available In this paper an enhanced approach based on a modified biogeography optimization with predator and prey behavior (PMBBO is presented. The approach uses several predators with new proposed prey’s movement formula. The potential of using a modified predator and prey model is to increase the diversification along the optimization process so to avoid local optima and reach the optimal solution quickly. The proposed approach is used in tuning the gains of PID controller for nonlinear systems (Mass spring damper and an inverted pendulum and has given remarkable results when compared to genetic algorithm and classical BBO.
Full Text Available La proliferación de métodos en las últimas décadas ha llevado a algunos autores a cuestionar si la biogeografía es una disciplina coherente. Las biotas son mosaicos complejos debidos a dispersión (expansión de las distribuciones y vicarianza (fragmentación de las distribuciones, teniendo historias complejas y reticuladas, que necesariamente deben estudiarse a través de la integración de diferentes metodologías. Un análisis biogeográfico evolutivo involucraría cinco etapas: (1 reconocimiento de componentes bióticos (conjuntos de taxa integrados espacio-temporalmente debido a una historia común, mediante la panbiogeografía y métodos para identificar áreas de endemismo; (2 contrastación de los componentes bióticos e identificación de los eventos vicariantes que los fragmentaron, mediante la biogeografía cladística y filogeografía comparada; (3 establecimiento de un arreglo jerárquico de los componentes en un sistema biogeográfico de reinos, regiones, dominios, provincias y distritos; (4 identificación de los cenocrones (conjuntos de taxa con edad y orígenes similares, datados mediante la filogeografía intraespecífica, relojes moleculares y fósiles; y (5 formulación de un escenario geobiótico, que explique la evolución de los componentes y cenocrones, integrando información geológica y tectónicaThe proliferation of methods in the last decades has led some authors to question whether biogeography is a coherent discipline. Biotas are complex mosaics due to dispersal (expansion of distributions and vicariance (fragmentation of distributions, having complex, reticulate histories, which necessarily need to be studied through the integration of different methodologies. An evolutionary biogeographical analysis may involve five steps: (1 recognition of biotic components (sets of spatio-temporally integrated taxa due to common history, through panbiogeography and methods used to identify areas of endemism; (2
Hoberg, E P; Zarlenga, D S
History is the foundation that informs about the nuances of faunal assembly that are essential in understanding the dynamic nature of the host-parasite interface. All of our knowledge begins and ends with evolution, ecology and biogeography, as these interacting facets determine the history of biodiverse systems. These components, relating to Haemonchus, can inform about the complex history of geographical distribution, host association and the intricacies of host-parasite associations that are played out in physiological and behavioural processes that influence the potential for disease and our capacity for effective control in a rapidly changing world. Origins and evolutionary diversification among species of the genus Haemonchus and Haemonchus contortus occurred in a complex crucible defined by shifts in environmental structure emerging from cycles of climate change and ecological perturbation during the late Tertiary and through the Quaternary. A history of sequential host colonization associated with waves of dispersal bringing assemblages of ungulates from Eurasia into Africa and processes emerging from ecosystems in collision and faunal turnover defined the arena for radiation among 12 recognized species of Haemonchus. Among congeners, the host range for H. contortus is exceptionally broad, including species among artiodactyls of 40 genera representing 5 families (and within 12 tribes of Bovidae). Broad host range is dramatically reflected in the degree to which translocation, introduction and invasion with host switching, has characterized an expanding distribution over time in North America, South America, southern Eurasia, Australia and New Zealand, coincidental with agriculture, husbandry and global colonization by human populations driven particularly by European exploration after the 1500s. African origins in xeric to mesic habitats of the African savannah suggest that historical constraints linked to ecological adaptations (tolerances and
Full Text Available This study presents an experimental approach to assess the relative importance of climatic and biotic factors as determinants of species' geographical distributions. We asked to what extent responses of grassland plant species to biotic interactions vary with climate, and to what degree this variation depends on the species' biogeography. Using a gradient from oceanic to continental climate represented by nine common garden transplant sites in Germany, we experimentally tested whether congeneric grassland species of different geographic distribution (oceanic vs. continental plant range type responded differently to combinations of climate, competition and mollusc herbivory. We found the relative importance of biotic interactions and climate to vary between the different components of plant performance. While survival and plant height increased with precipitation, temperature had no effect on plant performance. Additionally, species with continental plant range type increased their growth in more benign climatic conditions, while those with oceanic range type were largely unable to take a similar advantage of better climatic conditions. Competition generally caused strong reductions of aboveground biomass and growth. In contrast, herbivory had minor effects on survival and growth. Against expectation, these negative effects of competition and herbivory were not mitigated under more stressful continental climate conditions. In conclusion we suggest variation in relative importance of climate and biotic interactions on broader scales, mediated via species-specific sensitivities and factor-specific response patterns. Our results have important implications for species distribution models, as they emphasize the large-scale impact of biotic interactions on plant distribution patterns and the necessity to take plant range types into account.
Hu, Junhua; Liu, Yang
It remains a challenge to identify the geographical patterns and underlying environmental associations of species with unique ecological niches and distinct behaviors. This in turn hinders our understanding of the ecology as well as effective conservation management of threatened species. The white-eared night heron (Gorsachius magnificus) is a non-migratory nocturnal bird species that has a patchy distribution in the mountainous forests of East Asia. It is currently categorized as "Endangered" on the IUCN Red List, primarily due to its restricted range and fragmented habitat. To improve our knowledge of the biogeography and conservation of this species, we modeled the geographical pattern of its suitable habitat and evaluated the potential impacts of climate change using ecological niche modeling with a maximum entropy approach implemented in Maxent. Our results indicated that the amount of suitable habitat in all of East Asia was about 130 000 km(2), which can be spatially subdivided into several mountain ranges in southern and southwestern China and northern Vietnam. The extent of suitable habitat range may shrink by more than 35% under a predicted changing climate when assuming the most pessimistic condition of dispersal, while some more suitable habitat would be available if the heron could disperse unrestrainedly. The significant future changes in habitat suitability suggested for Gorsachius magnificus urge caution in any downgrading of Red List status that may be considered. Our results also discern potentially suitable areas for future survey efforts on new populations. Overall, this study demonstrates that ecological niche modeling offers an important tool for evaluating the habitat suitability and potential impacts of climate change on an enigmatic and endangered species based on limited presence data. PMID:24404169
Full Text Available It remains a challenge to identify the geographical patterns and underlying environmental associations of species with unique ecological niches and distinct behaviors. This in turn hinders our understanding of the ecology as well as effective conservation management of threatened species. The white-eared night heron (Gorsachius magnificus is a non-migratory nocturnal bird species that has a patchy distribution in the mountainous forests of East Asia. It is currently categorized as "Endangered" on the IUCN Red List, primarily due to its restricted range and fragmented habitat. To improve our knowledge of the biogeography and conservation of this species, we modeled the geographical pattern of its suitable habitat and evaluated the potential impacts of climate change using ecological niche modeling with a maximum entropy approach implemented in Maxent. Our results indicated that the amount of suitable habitat in all of East Asia was about 130 000 km(2, which can be spatially subdivided into several mountain ranges in southern and southwestern China and northern Vietnam. The extent of suitable habitat range may shrink by more than 35% under a predicted changing climate when assuming the most pessimistic condition of dispersal, while some more suitable habitat would be available if the heron could disperse unrestrainedly. The significant future changes in habitat suitability suggested for Gorsachius magnificus urge caution in any downgrading of Red List status that may be considered. Our results also discern potentially suitable areas for future survey efforts on new populations. Overall, this study demonstrates that ecological niche modeling offers an important tool for evaluating the habitat suitability and potential impacts of climate change on an enigmatic and endangered species based on limited presence data.
Tamar, Karin; Carranza, Salvador; Sindaco, Roberto; Moravec, Jiří; Trape, Jean-François; Meiri, Shai
Acanthodactylus lizards are among the most diverse and widespread diurnal reptiles in the arid regions spanning from North Africa across to western India. Acanthodactylus constitutes the most species-rich genus in the family Lacertidae, with over 40 recognized species inhabiting a wide variety of dry habitats. The genus has seldom undergone taxonomic revisions, and although there are a number of described species and species-groups, their boundaries, as well as their interspecific relationships, remain largely unresolved. We constructed a multilocus phylogeny, combining data from two mitochondrial (12S, cytb) and three nuclear (MC1R, ACM4, c-mos) markers for 302 individuals belonging to 36 known species, providing the first large-scale time-calibrated molecular phylogeny of the genus. We evaluated phylogenetic relationships between and within species-groups, and assessed Acanthodactylus biogeography across its known range. Acanthodactylus cladogenesis is estimated to have originated in Africa due to vicariance and dispersal events from the Oligocene onwards. Radiation started with the separation into three clades: the Western and scutellatus clades largely distributed in North Africa, and the Eastern clade occurring mostly in south-west Asia. Most Acanthodactylus species diverged during the Miocene, possibly as a result of regional geological instability and climatic changes. We support most of the current taxonomic classifications and phylogenetic relationships, and provide genetic validity for most species. We reveal a new distinct blanfordii species-group, suggest new phylogenetic positions (A. hardyi, A. masirae), and synonymize several species and subspecies (A. lineomaculatus, A. boskianus khattensis and A. b. nigeriensis) with their phylogenetically closely-related species. We recommend a thorough systematic revision of taxa, such as A. guineensis, A. grandis, A. dumerilii, A. senegalensis and the pardalis and erythrurus species-groups, which exhibit high
Mi-Mi LI; Jian-Hua LI; Peter DEL TREDICI; Jeffrey CORAJOD; Cheng-Xin FU
Despite several morphological and molecular analyses of Theaceae,several outstanding issues remain in the phylogenetics and biogeography of the family including the disputed relationships among the tribes Gordonieae,Stewartieae,and Theeae,the controversial taxonomic status of Hartia and Stewartia,and the unclear biogeographic history of Gordonieae and Stewartieae.In this study we gathered DNA sequences of multiple plastid genes from 27 species of Theaceae representing all genera except Laplacea,conducted phylogenetic analyses using parsimony,likelihood,and Bayesian methods,and estimated divergence times within a Bayesian framework with fossil calibrations and molecular data.Our data provided further support for the three tribes in the family and for the sistergroup relationship of Theeae to Stewartieae plus Gordonieae.Within Gordonieae,our study for the first time offered strong molecular support for the sister relationship of Franklinia and Schima.Within Stewartieae,our data supported the paraphyly of Stewartia including Hartia.Within Stewartia,our data for the first time suggested that North American (NA) species Stewartia ovata was more closely related to eastern Asian (EA) species than to the other NA species Stewartia malacodendron.Biogeographic analyses indicated that disjunct endemic species of Gordonieae might have originated from NA and those of Stewartieae from EA.Divergence times of the EA-NA disjunct pairs identified in this study (Franklinia and Schima in Gordonieae and S.ovata (NA) and Asian species of Stewartia) were estimated to be in the Mid-Miocene.Population exchanges in Gordonieae and Stewartieae may have occurred over the Bering land bridge prior to the Mid-Miocene.
The Red Sea is a unique marine ecosystem with contrasting gradients of temperature and salinity along its north-to-south axis. It is an extremely oligotrophic environment that is characterized by perpetual year-round water column stratification, high annual solar irradiation, and negligible riverine and precipitation inputs. In this study, we investigated whether the contemporary environmental conditions shape community assemblages by pyrosequencing 16S rRNA genes of bacteria in surface water samples collected from the northeastern half of this water body. A combined total of 1855 operational taxonomic units (OTUs) were recovered from the \\'small-cell\\' and \\'large-cell\\' fractions. Here, a few major OTUs affiliated with Cyanobacteria and Proteobacteria accounted for â93% of all sequences, whereas a tail of \\'rare\\' OTUs represented most of the diversity. OTUs allied to Surface 1a/b SAR11 clades and Prochlorococcus related to the high-light-adapted (HL2) ecotype were the most widespread and predominant sequence types. Interestingly, the frequency of taxa that are typically found in the upper mesopelagic zone was significantly elevated in the northern transects compared with those in the central, presumably as a direct effect of deep convective mixing in the Gulf of Aqaba and water exchange with the northern Red Sea. Although temperature was the best predictor of species richness across all major lineages, both spatial and environmental distances correlated strongly with phylogenetic distances. Our results suggest that the bacterial diversity of the Red Sea is as high as in other tropical seas and provide evidence for fundamental differences in the biogeography of pelagic communities between the northern and central regions. © 2011 Blackwell Publishing Ltd.
Forthman, Michael; Weirauch, Christiane
For at least the past 80my, Madagascar, a major biodiversity hotspot, has been isolated from all other landmasses. This long-term isolation, along with geologic and climatic factors within Madagascar and throughout the Indian Ocean, has undoubtedly influenced the evolution of the island's biota. However, few systematic analyses incorporating modern divergence dating and biogeographic analyses have focused on Madagascan insects. The diverse Madagascan millipede assassin bugs (Heteroptera: Reduviidae: Ectrichodiinae) offer an opportunity to contribute to a limited body of insect-related research that explores Madagascar's historical biogeography. A molecular dataset (COI mtDNA and 18S, 28S D2 and D3-D5 rDNAs) for 56 taxa (39 ingroup) and a combined morphological (145 characters) and molecular dataset for 110 taxa (93 ingroup) are analyzed with maximum likelihood (ML) and parsimony approaches. Based on the molecular ML phylogeny, divergence times were estimated using fossil and secondary calibrations and biogeographic analyses performed using DIVA, DEC, and DEC+j models to determine the role and patterns of vicariance and dispersal in the origin of Madagascan Ectrichodiinae. Results indicate that Ectrichodiinae in Madagascar do not form a monophyletic group, different clades are closely related to Afrotropical and Oriental lineages, and have colonized the island via transoceanic dispersal at least twice from the Oriental region and once from the Afrotropical region in the last ∼68my. Additionally, the DEC+j and DIVA models infer a single out-of-Madagascar dispersal event to the Afrotropical region. Oceanic and geologic factors that may have facilitated dispersal between these three regions are discussed. Results of the combined analyses are used to explore character support for Madagascan taxa and inform taxonomic diagnoses. Our results are congruent with the small but growing body of biogeographic research supporting Cenozoic transoceanic dispersal for Madagascan
Asefi Najafabady, S.; Welch, R. M.; Nair, U.; Lawton, R. O.; Ray, D.
Tropical montane cloud forests (TMCFs) are ecosystems characterized by frequent and prolonged immersion in orographic clouds. TMCFs are biologically rich and diverse and they lie at the core of several of the global biological hotspots identified for conservation purposes. Recent studies show that TMCFs are sensitive to global and regional scale climate changes. Vegetation in TMCFs directly harvest water from clouds, which is usually termed horizontal precipitation, and is an important input to local hydrological cycle. Mosses and ferns present within the TMCFs absorbs moisture during rainfall and releases slowly over time thereby providing another important hydrological function, namely modulation of runoff. In spite of the ecological and hydrological importance of TMCFs, there is scant information regarding the geographical distribution of the TMCFs. One source of information that is currently available is the atlas of the potential cloud forest distribution published by the United Nations Environmental Program. However, this compilation does not directly consider the defining characteristics of cloud forests, namely frequency of immersion in cloud forests, in their classisification scheme. This talk will present the use of NASA MODIS satellite data to determine cloud immersion frequency and thus the biogeography of cloud forests. The MODIS derived cloud top heights and cloud thickness estimated from MODIS retrieval of cloud microphysical properties is used to estimate cloud base height. If the estimate cloud base height at a location is less than or equal to the surface elevation at that point, then that location is defined as experiencing cloud immersion. This classification procedure was applied to determine cloud immersion frequency at two study sites, namely Hawaii and Monteverde, Costa Rica. The cloud immersion frequency maps identifies some of the know cloud forest locations in these study areas. Comparison against a blended product created using numerical
Van Houtan, Kyle S; Francke, Devon L; Alessi, Sarah; Jones, T Todd; Martin, Summer L; Kurpita, Lauren; King, Cheryl S; Baird, Robin W
High seas oceanic ecosystems are considered important habitat for juvenile sea turtles, yet much remains cryptic about this important life-history period. Recent progress on climate and fishery impacts in these so-called lost years is promising, but the developmental biogeography of hawksbill sea turtles (Eretmochelys imbricata) has not been widely described in the Pacific Ocean. This knowledge gap limits the effectiveness of conservation management for this globally endangered species. We address this with 30 years of stranding observations, 20 years of bycatch records, and recent simulations of natal dispersal trajectories in the Hawaiian Archipelago. We synthesize the analyses of these data in the context of direct empirical observations, anecdotal sightings, and historical commercial harvests from the insular Pacific. We find hawksbills 0-4 years of age, measuring 8-34 cm straight carapace length, are found predominantly in the coastal pelagic waters of Hawaii. Unlike other species, we find no direct evidence of a prolonged presence in oceanic habitats, yet satellite tracks of passive drifters (simulating natal dispersal) and our small sample sizes suggest that an oceanic phase for hawksbills cannot be dismissed. Importantly, despite over 600 million hooks deployed and nearly 6000 turtle interactions, longline fisheries have never recorded a single hawksbill take. We address whether the patterns we observe are due to population size and gear selectivity. Although most sea turtle species demonstrate clear patterns of oceanic development, hawksbills in the North Pacific may by contrast occupy a variety of ecosystems including coastal pelagic waters and shallow reefs in remote atolls. This focuses attention on hazards in these ecosystems - entanglement and ingestion of marine debris - and perhaps away from longline bycatch and decadal climate regimes that affect sea turtle development in oceanic regions. PMID:27110350
Snow, J. T.; Schlosser, C.; Woodward, E. M. S.; Mills, M. M.; Achterberg, E. P.; Mahaffey, C.; Bibby, T. S.; Moore, C. M.
The cyanobacterium Trichodesmium is responsible for a significant proportion of the annual "new" nitrogen introduced into the global ocean. Despite being arguably the best studied marine diazotroph, the factors controlling the distribution and growth of Trichodesmium remain a subject of debate, with sea surface temperature, the partial pressure of CO2, and nutrients including iron (Fe) and phosphorus (P), all suggested to be important. Synthesizing data from seven cruises collectively spanning large temporal and spatial scales across the Atlantic Ocean, including two previously unreported studies crossing the largely undersampled South Atlantic gyre, we assessed the relationship between proposed environmental drivers and both community N2 fixation rates and the distribution of Trichodesmium. Simple linear regression analysis would suggest no relationship between any of the sampled environmental variables and N2 fixation rates. However, considering the concentrations of iron and phosphorus together within a simplified resource-ratio framework, illustrated using an idealized numerical model, indicates the combined effects these nutrients have on Trichodesmium and broader diazotroph biogeography, alongside the reciprocal maintenance of different biogeographic provinces of the (sub)tropical Atlantic in states of Fe or P oligotrophy by diazotrophy. The qualitative principles of the resource-ratio framework are argued to be consistent with both the previously described North-South Atlantic contrast in Trichodesmium abundance and the presence and consequence of a substantial non-Trichodesmium diazotrophic community in the western South Atlantic subtropical gyre. A comprehensive, observation-based explanation of the interactions between Trichodesmium and the wider diazotrophic community with iron and phosphorus in the Atlantic Ocean is thus revealed.
Full Text Available Spatial patterns of species diversity provide information about the mechanisms that regulate biodiversity and are important for setting conservation priorities. Present knowledge of the biogeography of meiofauna in the deep sea is scarce. This investigation focuses on the distribution of the deep-sea nematode genus Manganonema, which is typically extremely rare in deep-sea sediment samples. Forty-four specimens of eight different species of this genus were recorded from different Atlantic and Mediterranean regions. Four out of the eight species encountered are new to science. We report here that this genus is widespread both in the Atlantic and in the Mediterranean Sea. These new findings together with literature information indicate that Manganonema is a cosmopolitan genus, inhabiting a variety of deep-sea habitats and oceans. Manganonema shows the highest diversity at water depths >4,000 m. Our data, therefore, indicate that this is preferentially an abyssal genus that is able, at the same time, to colonize specific habitats at depths shallower than 1,000 m. The analysis of the distribution of the genus Manganonema indicates the presence of large differences in dispersal strategies among different species, ranging from locally endemic to cosmopolitan. Lacking meroplanktonic larvae and having limited dispersal ability due to their small size, it has been hypothesized that nematodes have limited dispersal potential. However, the investigated deep-sea nematodes were present across different oceans covering macro-scale distances. Among the possible explanations (hydrological conditions, geographical and geological pathways, long-term processes, specific historical events, their apparent preference of colonizing highly hydrodynamic systems, could suggest that these infaunal organisms are transported by means of deep-sea benthic storms and turbidity currents over long distances.
Piatt, J.F.; Springer, A.M.
Despite its great distance from productive shelf-edge habitat, the inner shelf area of the Bering Sea, from St. Lawrence Island to the Bering Strait, supports a surprisingly large number (>5 million) of seabirds during summer, mostly small plantivorous auklets (65%) and large piscivorous murres (19%) and kittiwakes (5%). This paradox of seabird biogeography is explained by the Anadyr "Green Belt" - a current that advects nutrients and plankton over 1200 km from the outer Bering Sea shelf-edge to the central Chukchi Sea. Turbulent upwelling of this nutrient-rich water at Anadyr and Bering straits further enhances high levels of primary production:(360 gC m-2y-1) and helps sustain the enormous biomass of zooplankton entrained in the Anadyr Current. Primary production in adjacent waters of the Chukchi Sea (420 gC m-2y-1) exceeds that observed below Bering Strait, and zooplankton are equally abundant. Auklets account for 49% of total food consumption below Bering Strait (411 mt d-1), whereas piscivores dominate (88% of 179 mt d-1) in the Chukchi Sea. Of 2 million seabirds in the Chukchi region, auklets (6%) are supplanted by planktivorous phalaropes (25%), and piscivorous murres (38%) and kittiwakes (15%). Average carbon flux to seabirds (0.65 mgC m -2d-1) over the whole region is more typical of upwelling than shelf ecosystems. The pelagic distribution of seabirds in the region appears to be a function of advection, productivity and water column stability. Planktivores flourish in areas with high zooplankton concentrations on the edge of productive upwelling and frontal zones along the "Green Belt", whereas piscivores avoid turbulent, mixed waters and forage in stable, stratified waters along the coast and in the central Chukchi Sea.
Timothy R McClanahan
Full Text Available Coral reefs are biodiverse ecosystems structured by abiotic and biotic factors operating across many spatial scales. Regional-scale interactions between climate change, biogeography and fisheries management remain poorly understood. Here, we evaluated large-scale patterns of coral communities in the western Indian Ocean after a major coral bleaching event in 1998. We surveyed 291 coral reef sites in 11 countries and over 30° of latitude between 2004 and 2011 to evaluate variations in coral communities post 1998 across gradients in latitude, mainland-island geography and fisheries management. We used linear mixed-effect hierarchical models to assess total coral cover, the abundance of four major coral families (acroporids, faviids, pocilloporids and poritiids, coral genus richness and diversity, and the bleaching susceptibility of the coral communities. We found strong latitudinal and geographic gradients in coral community structure and composition that supports the presence of a high coral cover and diversity area that harbours temperature-sensitive taxa in the northern Mozambique Channel between Tanzania, northern Mozambique and northern Madagascar. Coral communities in the more northern latitudes of Kenya, Seychelles and the Maldives were generally composed of fewer bleaching-tolerant coral taxa and with reduced richness and diversity. There was also evidence for continued declines in the abundance of temperature-sensitive taxa and community change after 2004. While there are limitations of our regional dataset in terms of spatial and temporal replication, these patterns suggest that large-scale interactions between biogeographic factors and strong temperature anomalies influence coral communities while smaller-scale factors, such as the effect of fisheries closures, were weak. The northern Mozambique Channel, while not immune to temperature disturbances, shows continued signs of resistance to climate disturbances and remains a priority for
Miracle, M Eulàlia Gassó
C.J. Temminck, director of the Rijksmuseum van Natuurlijke Historie (now the National Museum of Natural History in Leiden) and a renowned ornithologist, gained his contemporary's respect thanks to the description of many new species and to his detailed monographs on birds. He also published a small number of works on biogeography describing the fauna of the Dutch colonies in South East Asia and Japan. These works are remarkable for two reasons. First, in them Temminck accurately described the species composition of poorly explored regions, like the Sunda Islands and Japan. Secondly, he formulated a new law on the geographical distribution of animals around the globe, based on the parallels he observed between the fauna from Europe, Asia and Japan. The underlying ideas that lead Temminck to this law were the type-concept, which he understood as the ideal morphological plan behind animal form, the unchanging character of the species and a strong belief in nature's divine design. During the first half of the nineteenth century, the type- and the species-concept, the origin and fixity of the species and the meaning of variations aroused heated discussions. When put in the context of his time, Temminck emerges as a scientist whose work was driven by the dominating scientific philosophy of the time in which he lived, under the influence of late eighteenth century natural history and of French empiricists, in particular, the great zoologist and paleontologist Georges Cuvier. Temminck's detailed descriptions of the Dutch East Indian fauna helped the great naturalists after him to understand nature's patterns and to propose comprehensive theories that explain its diversity. PMID:19244845
Sanin, Camilo; Cadena, Carlos Daniel; Maley, James M.; Lijtmaer, Dario A.; Tubaro, Pablo L.; Chesser, R. Terry
The Andes are a hotspot of global avian diversity, but studies on the historical diversification of Andean birds remain relatively scarce. Evolutionary studies on avian lineages with Andean–Patagonian distributions have focused on reconstructing species-level phylogenies, whereas no detailed phylogeographic studies on widespread species have been conducted. Here, we describe phylogeographic patterns in the Bar-winged Cinclodes (Cinclodes fuscus), a widespread and common species of ovenbird (Furnariidae) that breeds from Tierra del Fuego to the northern Andes. Traditionally, C. fuscus has been considered a single species composed of nine subspecies, but its long and narrow range suggests the possibility of considerable genetic variation among populations. Sequences of two mitochondrial genes revealed three discrete and geographically coherent groups of C. fuscus, occupying the southern, central, and northern Andes. Surprisingly, phylogenetic analyses indicated that these groups were more closely related to other species of Cinclodes than to each other. Relationships of the southern and northern C. fuscus clades to other species of Cinclodes were straightforward; in combination with available information on plumage, behavioral, and vocal variation, this suggests that each should be recognized as a distinct biological species. The central Andean group was paraphyletic with respect to C. oustaleti, and relationships among these taxa and C. olrogi were poorly resolved. We suggest that the central Andean C. fuscus should also be considered a different species, pending new information to clarify species limits in this group. These new phylogenetic data, along with recently developed methods, allowed us to review the biogeography of the genus, confirming southern South America and the central Andes as important areas for the diversification of these birds.
D Ross Robertson
Full Text Available The Greater Caribbean biogeographic region is the high-diversity heart of the Tropical West Atlantic, one of four global centers of tropical marine biodiversity. The traditional view of the Greater Caribbean is that it is limited to the Caribbean, West Indies, southwest Gulf of Mexico and tip of Florida, and that, due to its faunal homogeneity, lacks major provincial subdivisions. In this scenario the northern 2/3 of the Gulf of Mexico and southeastern USA represent a separate temperate, "Carolinian" biogeographic region. We completed a comprehensive re-assessment of the biogeography of the Greater Caribbean by comparing the distributions of 1,559 shorefish species within 45 sections of shelf waters of the Greater Caribbean and adjacent areas. This analysis shows that that the Greater Caribbean occupies a much larger area than usually thought, extending south to at least Guyana, and north to encompass the entire Carolinian area. Rather than being homogenous, the Greater Caribbean is divided into three major provinces, each with a distinctive, primarily tropical fauna: (1 a central, tropical province comprising the West Indies, Bermuda and Central America; (2 a southern, upwelling-affected province spanning the entire continental shelf of northern South America; and (iii a northern, subtropical province that includes all of the Gulf of Mexico, Florida and southeastern USA. This three-province pattern holds for both reef- and soft bottom fishes, indicating a general response by demersal fishes to major variation in provincial shelf environments. Such environmental differences include latitudinal variation in sea temperature, availability of major habitats (coral reefs, soft bottom shorelines, and mangroves, and nutrient additions from upwelling areas and large rivers. The three-province arrangement of the Greater Caribbean broadly resembles and has a similar environmental basis to the provincial arrangement of its sister biogeographic region, the
Review of: Ne'eman, G. & Trabaud, L. Ecology, Biogeography and Management of Pinus halepensis and P. brutia Forest Ecosystems in the Mediterranean Basin. xii + 412 pp. Backhuys Publishers, Leiden. ISBN 90?5782-055-2 (hardcover). Price: USD 120.00.
Müller, C. J.; Matos Maravi, Pavel F.; Beheregaray, L. B.
Roč. 40, č. 5 (2013), s. 881-893. ISSN 0305-0270 Institutional support: RVO:60077344 Keywords : butterflies * DEC model * historical biogeography Subject RIV: EG - Zoology Impact factor: 4.969, year: 2013 http://onlinelibrary.wiley.com/doi/10.1111/jbi.12040/pdf
Tchaicka, Ligia; Freitas, Thales Renato Ochotorena de; Bager, Alex; Vidal, Stela Luengos; Lucherini, Mauro; Iriarte, Agustín; Novaro, Andres; Geffen, Eli; Garcez, Fabricio Silva; Johnson, Warren E; Wayne, Robert K; Eizirik, Eduardo
To investigate the evolution and biogeography of an endemic group of South American foxes, we examined mitochondrial DNA control region sequences for 118 individuals belonging to all six extant species of the genus Lycalopex. Phylogenetic and molecular dating analyses supported the inference that this genus has undergone a very recent and rapid radiation, stemming from a common ancestor that lived ca. 1 million years ago. The Brazilian endemic L. vetulus was supported as the most basal species in this genus, whereas the most internal group is comprised by the recently diverged (ca. 350,000 years ago) Andean/Patagonian species L. griseus and L. culpaeus. We discuss the inferred phylogenetic relationships and divergence times in the context of the current geographic distributions of these species, and the likely effects of Pleistocene climatic changes on the biogeography of this group. Furthermore, a remarkable finding was the identification of multiple individuals classified as L. gymnocercus bearing mtDNA haplotypes clearly belonging to L. griseus, sampled in regions where the latter is not known to occur. At a minimum, this result implies the need to clarify the present-day geographic distribution of each of these fox species, while it may also indicate an ongoing hybridization process between them. Future testing of this hypothesis with in-depth analyses of these populations is thus a priority for understanding the history, evolutionary dynamics and present-day composition of this endemic Neotropical genus. PMID:27560989
Full Text Available Databases are an essential tool and resource within the field of bioinformatics. The primary aim of this study was to generate an overview of global bacterial biodiversity and biogeography using available data from the two largest public online databases, NCBI Nucleotide and GBIF. The secondary aim was to highlight the contribution each geographic area has to each database. The basis for data analysis of this study was the metadata provided by both databases, mainly, the taxonomy and the geographical area origin of isolation of the microorganism (record. These were directly obtained from GBIF through the online interface, while E-utilities and Python were used in combination with a programmatic web service access to obtain data from the NCBI Nucleotide Database. Results indicate that the American continent, and more specifically the USA, is the top contributor, while Africa and Antarctica are less well represented. This highlights the imbalance of exploration within these areas rather than any reduction in biodiversity. This study describes a novel approach to generating global scale patterns of bacterial biodiversity and biogeography and indicates that the Proteobacteria are the most abundant and widely distributed phylum within both databases.
Foukal, Nicholas P.; Thomas, Andrew C.
Thirteen years (1998-2010) of satellite-measured chlorophyll a are used to establish spatial patterns in climatological phytoplankton biomass seasonality across the California Current System (CCS) and its interannual variability. Multivariate clustering based on the shape of the local climatological seasonal cycle divides the study area into four groups: two with spring-summer maxima representing the northern and southern coastal upwelling zones, one with a summer minimum offshore in mid-latitudes and a fourth with very weak seasonality in between. Multivariate clustering on the seasonal cycles from all 13 years produces the same four seasonal cycle types and provides a view of the interannual variability in seasonal biogeography. Over the study period these seasonal cycles generally appear in similar locations as the climatological clusters. However, considerable interannual variability in the geography of the seasonal cycles is evident across the CCS, the most spatially extensive of which are associated with the 1997-1999 El Niño-Southern Oscillation (ENSO) signal and the 2005 delayed spring transition off the Oregon and northern and central California coasts. We quantify linear trends over the study period in the seasonal timing of the two seasonal cycles that represent the biologically productive coastal upwelling zones using four different metrics of phenology. In the northern upwelling region, the date of the spring maximum is delaying (1.34 days yr-1) and the central tendency of the summer elevated chlorophyll period is advancing (0.63 days yr-1). In the southern coastal upwelling region, both the initiation and cessation of the spring maximum are delaying (1.78 days yr-1 and 2.44 days yr-1, respectively) and the peak is increasing in duration over the study period. Connections between observed interannual shifts in phytoplankton seasonality and physical forcing, expressed as either basin-scale climate signals or local forcing, show phytoplankton
Full Text Available Like hydrothermal vents along oceanic ridges, cold seeps are patchy and isolated ecosystems along continental margins, extending from bathyal to abyssal depths. The Atlantic Equatorial Belt (AEB, from the Gulf of Mexico to the Gulf of Guinea, was one focus of the Census of Marine Life ChEss (Chemosynthetic Ecosystems program to study biogeography of seep and vent fauna. We present a review and analysis of collections from five seep regions along the AEB: the Gulf of Mexico where extensive faunal sampling has been conducted from 400 to 3300 m, the Barbados accretionary prism, the Blake ridge diapir, and in the Eastern Atlantic from the Congo and Gabon margins and the recently explored Nigeria margin. Of the 72 taxa identified at the species level, a total of 9 species or species complexes are identified as amphi-Atlantic. Similarity analyses based on both Bray Curtis and Hellinger distances among 9 faunal collections, and principal component analysis based on presence/absence of megafauna species at these sites, suggest that within the AEB seep megafauna community structure is influenced primarily by depth rather than by geographic distance. Depth segregation is observed between 1000 and 2000 m, with the middle slope sites either grouped with those deeper than 2000 m or with the shallower sites. The highest level of community similarity was found between the seeps of the Florida escarpment and Congo margin. In the western Atlantic, the highest degree of similarity is observed between the shallowest sites of the Barbados prism and of the Louisiana slope. The high number of amphi-atlantic cold-seep species that do not cluster according to biogeographic regions, and the importance of depth in structuring AEB cold-seep communities are the major conclusions of this study. The hydrothermal vent sites along the Mid Atlantic Ridge (MAR did not appear as "stepping stones" for dispersal of the AEB seep fauna, however, the south MAR and off axis regions
Highlights: • New method for dynamic economic dispatch problem using POLBBO. • Considering valve-point effects, ramp rate limits, transmission network losses. • POLBBO is able to balance the global exploration and the local exploitation. • An effective simultaneous constraints handling technique is proposed. • The achieved results by POLBBO are better than those reported in other literatures. - Abstract: Shortage of energy resources, rising power generation cost, and increasing electric energy demand make the dynamic economic dispatch (DED) increasingly necessary in today’s competitive electricity market. In this paper, an enhanced biogeography-based optimization (BBO) referred to as POLBBO is proposed to solve the DED problem with valve-point effects. BBO is a relatively new powerful population-based meta-heuristic algorithm inspired by biogeography and has been extensively applied to many scientific and engineering problems. However, its direct-copying-based migration and random mutation operators make BBO possess good local exploitation ability but lack enough global exploration ability. To remedy the defect, on one hand, an efficient operator named polyphyletic migration operator is proposed to enhance the search ability of POLBBO. This operator can not only generate new features from more promising areas in the search space, but also effectively increase the population diversity. On the other hand, an orthogonal learning (OL) strategy based on orthogonal experimental design is presented. The OL strategy can quickly discover useful information from the search experiences and effectively utilize the information to construct a more promising solution, and thereby provide a systematic and elaborate reasoning method to guide the search directions of POLBBO. In addition, an effective simultaneous constraints handling technique without penalty factor settings is developed to handle various complicated constraints of the DED problem. Finally, four test
Cantley, Jason T; Markey, Adrienne S; Swenson, Nathan G; Keeley, Sterling C
The historical biogeography of many lineages-of both terrestrial and marine ocean habitats-remains poorly investigated even though remote ocean habitat covers approximately 66% of the Earth's surface. One such lineage with poorly understood biogeographic affinities across vast ocean habitat is the genus Coprosma (Rubiaceae) with numerous species, and a widespread and disjunct distribution among the far-flung insular localities of multiple Pacific Islands. Here, the first taxonomically robust phylogeny for Coprosma s.s. was dated using molecular clock techniques and indicated Coprosma s.s. diverged from its sister genus Nertera likely during or shortly after the Oligocene Marine Transgression of New Zealand. Diversification of the five major clades identified occurred in New Zealand during the Miocene, which was then followed by multiple independent dispersals from New Zealand to various localities in many directions. The pattern of Coprosma's distribution in the Pacific appears stochastic both temporally and spatially, but evolution of an orange to red fruit colour prior to nearly all inferred dispersals hints at endozoochory by birds. The number of inferred long-distance dispersals of Coprosma s.s. (>30), and number of repeated dispersals to the same insular locality from unrelated Coprosma s.s. sublineages (>8) is perhaps the most currently known for a remote Pacific-centred genus investigated to date. A New Zealand origin for a Pacific-wide dispersal of taxa is not novel, but the manner in which the temporal and spatial distribution for Coprosma s.s. was achieved contributes to a novel understanding of the historical biogeography of widespread Pacific genera that have origins in the Southern Hemisphere. PMID:27339053
Cantley, Jason T.; Markey, Adrienne S.; Swenson, Nathan G.; Keeley, Sterling C.
The historical biogeography of many lineages—of both terrestrial and marine ocean habitats—remains poorly investigated even though remote ocean habitat covers approximately 66% of the Earth’s surface. One such lineage with poorly understood biogeographic affinities across vast ocean habitat is the genus Coprosma (Rubiaceae) with numerous species, and a widespread and disjunct distribution among the far-flung insular localities of multiple Pacific Islands. Here, the first taxonomically robust phylogeny for Coprosma s.s. was dated using molecular clock techniques and indicated Coprosma s.s. diverged from its sister genus Nertera likely during or shortly after the Oligocene Marine Transgression of New Zealand. Diversification of the five major clades identified occurred in New Zealand during the Miocene, which was then followed by multiple independent dispersals from New Zealand to various localities in many directions. The pattern of Coprosma’s distribution in the Pacific appears stochastic both temporally and spatially, but evolution of an orange to red fruit colour prior to nearly all inferred dispersals hints at endozoochory by birds. The number of inferred long-distance dispersals of Coprosma s.s. (>30), and number of repeated dispersals to the same insular locality from unrelated Coprosma s.s. sublineages (>8) is perhaps the most currently known for a remote Pacific-centred genus investigated to date. A New Zealand origin for a Pacific-wide dispersal of taxa is not novel, but the manner in which the temporal and spatial distribution for Coprosma s.s. was achieved contributes to a novel understanding of the historical biogeography of widespread Pacific genera that have origins in the Southern Hemisphere. PMID:27339053
Matos Maravi, Pavel F.; Núňez Águila, R.; Peňa, C.; Miller, J.; Sourakov, A.; Wahlberg, N.
Roč. 14, 1 /article number 199/ (2014). ISSN 1471-2148 Grant ostatní: GA JU(CZ) 156/2013/P; National Geographic Society(US) 5717-96 Institutional support: RVO:60077344 Keywords : Caribbean * ecological limits * historical biogeography Subject RIV: EH - Ecology, Behaviour Impact factor: 3.368, year: 2014 http://www.biomedcentral.com/content/pdf/s12862-014-0199-7.pdf
PATRICIO A. CAMUS
literature review on the marine biogeography of Chile and related subjects, with the following objectives: (a to summarize the oceanographic, climatic and geomorphologic characteristics of the Chilean continental coast; (b to discuss 27 biogeographic classifications published for the Chilean coast, analyzing both the procedures and criteria used by their authors, along with their main conclusions and agreements; (c to assess the vicariant and dispersal processes associated with the displacement and modification of the regional biotas, regarding the available antecedentes on the prevailing conditions and main events during the Tertiary and Quaternary periods; and (d to propose a scenario of biogeographic change based on historical determinants and their influence on the formation, character, and dynamics of biotas along the Chilean coast, emphasizing the identification and biogeographic nature of the main spatial units. From the preceding information, I propose a hypothesis of biogeographic classification for the level of biotas, not necessarily coincident with prior studies at lower levels such as flora or fauna. This classification identifies three major spatial units: a southern area which comprises an austral biota (Magellan Province, a northern area which comprises a warm-temperate biota (Peruvian Province, and a non transitional, Intermediate Area including mixed components of biota and exhibiting a poor biogeographic definition of both its character and hierarchical rank. I also discuss the different nature of two transitional zones located at the boundaries of the Intermediate Area, a southward induced transition and a northward contact transition, likely produced by the migration of biotas and glacial-tectonic events, respectively
Zhang, Xian-Zhi; Zeng, Chun-Xia; Ma, Peng-Fei; Haevermans, Thomas; Zhang, Yu-Xiao; Zhang, Li-Na; Guo, Zhen-Hua; Li, De-Zhu
In this paper we investigate the biogeography of the temperate woody bamboos (Arundinarieae) using a densely-sampled phylogenetic tree of Bambusoideae based on six plastid DNA loci, which corroborates the previously discovered 12 lineages (I-XII) and places Kuruna as sister to the Chimonocalamus clade. Biogeographic analyses revealed that the Arundinarieae diversified from an estimated 12 to 14Mya, and this was followed by rapid radiation within the lineages, particularly lineages IV, V and VI, starting from c. 7-8Mya. It is suggested that the late Miocene intensification of East Asian monsoon may have contributed to this burst of diversification. The possibilities of the extant Sri Lankan and African temperate bamboo lineages representing 'basal elements' could be excluded, indicating that there is no evidence to support the Indian or African route for migration of temperate bamboo ancestors to Asia. Radiations from eastern Asia to Africa, Sri Lanka, and to North America all are likely to have occurred during the Pliocene, to form the disjunct distribution of Arundinarieae we observe today. The two African lineages are inferred as being derived independently from Asian ancestors, either by overland migrations or long-distance dispersals. Beringian migration may explain the eastern Asian-eastern North American disjunction. PMID:26723898
Full Text Available Abstract Background The fungal genus Serpula (Serpulaceae, Boletales comprises several saprotrophic (brown rot taxa, including the aggressive house-infecting dry rot fungus Serpula lacrymans. Recent phylogenetic analyses have indicated that the ectomycorrhiza forming genera Austropaxillus and Gymnopaxillus cluster within Serpula. In this study we use DNA sequence data to investigate phylogenetic relationships, historical biogeography of, and nutritional mode transitions in Serpulaceae. Results Our results corroborate that the two ectomycorrhiza-forming genera, Austropaxillus and Gymnopaxillus, form a monophyletic group nested within the saprotrophic genus Serpula, and that the Serpula species S. lacrymans and S. himantioides constitute the sister group to the Austropaxillus-Gymnopaxillus clade. We found that both vicariance (Beringian and long distance dispersal events are needed to explain the phylogeny and current distributions of taxa within Serpulaceae. Our results also show that the transition from brown rot to mycorrhiza has happened only once in a monophyletic Serpulaceae, probably between 50 and 22 million years before present. Conclusions This study supports the growing understanding that the same geographical barriers that limit plant- and animal dispersal also limit the spread of fungi, as a combination of vicariance and long distance dispersal events are needed to explain the present patterns of distribution in Serpulaceae. Our results verify the transition from brown rot to ECM within Serpulaceae between 50 and 22 MyBP.
Lanping ZHENG; Junxing YANG; Xiaoyong CHEN
The Labeoninae is a subfamily of the family Cyprinidae,Order Cypriniformes.Oromandibular morphology within the Labeoninae is the greatest among cyprinid fishes.Although several phylogenetic studies about labeonines have been undertaken the results have been inconsistent and a comprehensive phylogeny is needed.Further,an incongruence between morphological and molecular phylogeny requires a systematic exploration of the significance of morphological characters on the basis of the molecular phylogeny.In this study,a total of 292 nucleotide sequences from 73 individuals (representing 24 genera and 73 species) of Labeoninae were analyzed.The results of the phylogenetic analysis indicate that there are four major clades within Labeoninae and three monophyletic lineages within the fourth clade.Results of the character evolution show that all oromandibular morphological characters are homoplastically distributed on the molecular phylogenetic tree and suggests that these characters evolved several times during the history of labeonines.In particular,the labeonine,a specific disc on the lower lip,has been acquired three times and reversed twice.These morphological characters do not have systematic significance but can be useful for taxonomy.The results of biogeography suggest that the Labeoninae originated from Southeast Asia and separately dispersed to Africa,East Asia and South Asia.
Sérgio L. Pereira
Full Text Available Most Neotropical birds, including Pteroglossus aracaris, do not have an adequate fossil record to be used as time constraints in molecular dating. Hence, the evolutionary timeframe of the avian biota can only be inferred using alternative time constraints. We applied a Bayesian relaxed clock approach to propose an alternative interpretation for the historical biogeography of Pteroglossus based on mitochondrial DNA sequences, using different combinations of outgroups and time constraints obtained from outgroup fossils, vicariant barriers and molecular time estimates. The results indicated that outgroup choice has little effect on the Bayesian posterior distribution of divergence times within Pteroglossus , that geological and molecular time constraints seem equally suitable to estimate the Bayesian posterior distribution of divergence times for Pteroglossus , and that the fossil record alone overestimates divergence times within the fossil-lacking ingroup. The Bayesian estimates of divergence times suggest that the radiation of Pteroglossus occurred from the Late Miocene to the Pliocene (three times older than estimated by the “standard” mitochondrial rate of 2% sequence divergence per million years, likely triggered by Andean uplift, multiple episodes of marine transgressions in South America, and formation of present-day river basins. The time estimates are in agreement with other Neotropical taxa with similar geographic distributions.
Kivelä, Mikko; Arnaud-Haond, Sophie; Saramäki, Jari
The recent application of graph-based network theory analysis to biogeography, community ecology and population genetics has created a need for user-friendly software, which would allow a wider accessibility to and adaptation of these methods. EDENetworks aims to fill this void by providing an easy-to-use interface for the whole analysis pipeline of ecological and evolutionary networks starting from matrices of species distributions, genotypes, bacterial OTUs or populations characterized genetically. The user can choose between several different ecological distance metrics, such as Bray-Curtis or Sorensen distance, or population genetic metrics such as FST or Goldstein distances, to turn the raw data into a distance/dissimilarity matrix. This matrix is then transformed into a network by manual or automatic thresholding based on percolation theory or by building the minimum spanning tree. The networks can be visualized along with auxiliary data and analysed with various metrics such as degree, clustering coefficient, assortativity and betweenness centrality. The statistical significance of the results can be estimated either by resampling the original biological data or by null models based on permutations of the data. PMID:24902875
Genevcius, Bruno C; Schwertner, Cristiano F
Chinavia is one of the most diverse genera of Pentatomidae, comprising 80 species distributed in the Afrotropical, Neartic and Neotropical regions. Some groups of species have been proposed in the literature based on morphological similarities or phylogenetic analyses. The geniculata group was proposed to include C. geniculata, C. gravis and C. nigritarsis. However, eleven other species of Chinavia share somatic and genital characteristics with C. geniculata, C. gravis and C. nigritarsis, which allows hypothesizing the monophyly among these 14 species. In spite of the recent contributions to aspects of biology, immature stages and species catalogs in Chinavia, the definition of monophyletic groups within the genus and the establishment of boundaries among its species are essential to understand its diversity and to test hypotheses on biogeography and evolutionary biology. In this study we review the taxonomy of the geniculata group, test its monophyly and propose a phylogenetic hypothesis for the group. We discuss the phylogenetic relationships from a geographical perspective, and provide insights about morphological evolution. PMID:25112324
Pagenkopp Lohan, K M; Fleischer, R C; Carney, K J; Holzer, K K; Ruiz, G M
Ships' ballast water (BW) commonly moves macroorganisms and microorganisms across the world's oceans and along coasts; however, the majority of these microbial transfers have gone undetected. We applied high-throughput sequencing methods to identify microbial eukaryotes, specifically emphasizing the protistan parasites, in ships' BW collected from vessels calling to the Chesapeake Bay (Virginia and Maryland, USA) from European and Eastern Canadian ports. We utilized tagged-amplicon 454 pyrosequencing with two general primer sets, amplifying either the V4 or V9 domain of the small subunit (SSU) of the ribosomal RNA (rRNA) gene complex, from total DNA extracted from water samples collected from the ballast tanks of bulk cargo vessels. We detected a diverse group of protistan taxa, with some known to contain important parasites in marine systems, including Apicomplexa (unidentified apicomplexans, unidentified gregarines, Cryptosporidium spp.), Dinophyta (Blastodinium spp., Euduboscquella sp., unidentified syndinids, Karlodinium spp., Syndinium spp.), Perkinsea (Parvilucifera sp.), Opisthokonta (Ichthyosporea sp., Pseudoperkinsidae, unidentified ichthyosporeans), and Stramenopiles (Labyrinthulomycetes). Further characterization of groups with parasitic taxa, consisting of phylogenetic analyses for four taxa (Cryptosporidium spp., Parvilucifera spp., Labyrinthulomycetes, and Ichthyosporea), revealed that sequences were obtained from both known and novel lineages. This study demonstrates that high-throughput sequencing is a viable and sensitive method for detecting parasitic protists when present and transported in the ballast water of ships. These data also underscore the potential importance of human-aided dispersal in the biogeography of these microbes and emerging diseases in the world's oceans. PMID:26476551
Hoberg, E P; Klassen, G J
Parasites are integral components of marine ecosystems, a general observation accepted by parasitologists, but often considered of trifling significance to the broader community of zoologists. Parasites, however, represent elegant tools to explore the origins, distribution and maintenance of biodiversity. Among these diverse assemblages, host and geographic ranges described by various helminths are structured and historically constrained by genealogical and ecological associations that can be revealed and evaluated using phylogenetic methodologies within the context of frameworks and hypotheses for co-evolution and historical biogeography. Despite over 200 years of sporadic investigations of helminth systematics, knowledge of parasite faunal diversity in chondrichthyan and osteichthyan fishes, seabirds and marine mammals remains to be distilled into a coherent and comprehensive picture that can be assessed using phylogenetic approaches. Phylogenetic studies among complex host-parasite assemblages that encompass varying temporal and geographic scales are the critical context for elucidating biodiversity and faunal structure, and for identifying historical and contemporary determinants of ecological organization and biogeographic patterns across the marine biosphere. Insights from phylogenetic inference indicate (1) the great age of marine parasite faunas; (2) a significant role for colonization in diversification across a taxonomic continuum at deep and relatively recent temporal scales; and (3) a primary role for allopatric speciation. Integration of ecological and phylogenetic knowledge from the study of parasites is synergistic, contributing substantial insights into the history and maintenance of marine systems. PMID:12396213
Rodolpho Santos Telles Menezes
Full Text Available The Neotropical Region harbors high biodiversity and many studies on mammals, reptiles, amphibians and avifauna have investigated the causes for this pattern. However, there is a paucity of such studies that focus on Neotropical insect groups. Synoeca de Saussure, 1852 is a Neotropical swarm-founding social wasp genus with five described species that is broadly and conspicuously distributed throughout the Neotropics. Here, we infer the phylogenetic relationships, diversification times, and historical biogeography of Synoeca species. We also investigate samples of the disjoint populations of S. septentrionalis that occur in both northwestern parts of South America through Central American and the Brazilian Atlantic rainforests. Our results showed that the interspecific relationships for Synoeca could be described as follows: (S. chalibea + S. virginea + (S. cyanea + (S. septentrionalis/S. surinama. Notably, samples of S. septentrionalis and S. surinama collected in the Atlantic Forest were interrelated and may be the result of incomplete lineage sorting and/or mitochondrial introgression among them. Our Bayesian divergence dating analysis revealed recent Plio-Pleistocene diversification in Synoeca. Moreover, our biogeographical analysis suggested an Amazonian origin of Synoeca, with three main dispersal events subsequently occurring during the Plio-Pleistocene.
Full Text Available Extinctions and declines of large marine vertebrates have major ecological impacts and are of critical concern in marine environments. The Caribbean monk seal, Monachus tropicalis, last definitively reported in 1952, was one of the few marine mammal species to become extinct in historical times. Despite its importance for understanding the evolutionary biogeography of southern phocids, the relationships of M.tropicalis to the two living species of critically endangered monk seals have not been resolved. In this study we present the first molecular data for M. tropicalis, derived from museum skins. Phylogenetic analysis of cytochrome b sequences indicates that M. tropicalis was more closely related to the Hawaiian rather than the Mediterranean monk seal. Divergence time estimation implicates the formation of the Panamanian Isthmus in the speciation of Caribbean and Hawaiian monk seals. Molecular, morphological and temporal divergence between the Mediterranean and “New World monk seals” (Hawaiian and Caribbean is profound, equivalent to or greater than between sister genera of phocids. As a result, we classify the Caribbean and Hawaiian monk seals together in a newly erected genus, Neomonachus. The two genera of extant monk seals (Monachus and Neomonachus represent old evolutionary lineages each represented by a single critically endangered species, both warranting continuing and concerted conservation attention and investment if they are to avoid the fate of their Caribbean relative.
Morrissey, Barbara J; Helgason, Thorunn; Poppinga, Lena; Fünfhaus, Anne; Genersch, Elke; Budge, Giles E
American foulbrood is the most destructive brood disease of honeybees (Apis mellifera) globally. The absence of a repeatable, universal typing scheme for the causative bacterium Paenibacillus larvae has restricted our understanding of disease epidemiology. We have created the first multilocus sequence typing scheme (MLST) for P. larvae, which largely confirms the previous enterobacterial repetitive intergenic consensus (ERIC)-polymerase chain reaction (PCR)-based typing scheme's divisions while providing added resolution and improved repeatability. We have used the new scheme to determine the distribution and biogeography of 294 samples of P. larvae from across six continents. We found that of the two most epidemiologically important ERIC types, ERIC I was more diverse than ERIC II. Analysis of the fixation index (FST ) by distance suggested a significant relationship between genetic and geographic distance, suggesting that population structure exists in populations of P. larvae. Interestingly, this effect was only observed within the native range of the host and was absent in areas where international trade has moved honeybees and their disease. Correspondence analysis demonstrated similar sequence type (ST) distributions between native and non-native countries and that ERIC I and II STs mainly have differing distributions. The new typing scheme facilitates epidemiological study of this costly disease of a key pollinator. PMID:25244044
Beckman, Elizabeth J; Witt, Christopher C
Time-calibrated molecular phylogenies can help us to understand the origins of the diverse and unique Andean avifauna. Previous studies have shown that the tempo of diversification differed between the Andes and adjacent lowland regions of South America. Andean taxa were found to have speciated more recently and to have avoided the decelerated diversification that is typical of Neotropical lowland clades. The South American siskins, a Pleistocene finch radiation, may typify this Andean pattern. We investigated the phylogenetic biogeography of all the New World siskins and goldfinches in new detail. To understand the specific role of the Andes in siskin diversification, we asked: (1) Was diversification faster in Andean siskin lineages relative to non-Andean ones? (2) Did siskin lineages move into and out of the Andes at different rates? We found that siskin lineages in the Andes had higher diversification rates and higher outward dispersal rates than siskin lineages outside the Andes. We conclude that páramo expansion and contraction in response to Pleistocene climatic cycles caused accelerated diversification and outward dispersal in Andean siskins. The younger average age of bird species in the Andes compared to lowland South America may be attributable to bursts of recent diversification in siskins and several other vagile, open-habitat clades. PMID:25796324
Menezes, Rodolpho Santos Telles; Brady, Seán Gary; Carvalho, Antônio Freire; Del Lama, Marco Antonio; Costa, Marco Antônio
The Neotropical Region harbors high biodiversity and many studies on mammals, reptiles, amphibians and avifauna have investigated the causes for this pattern. However, there is a paucity of such studies that focus on Neotropical insect groups. Synoeca de Saussure, 1852 is a Neotropical swarm-founding social wasp genus with five described species that is broadly and conspicuously distributed throughout the Neotropics. Here, we infer the phylogenetic relationships, diversification times, and historical biogeography of Synoeca species. We also investigate samples of the disjoint populations of S. septentrionalis that occur in both northwestern parts of South America through Central American and the Brazilian Atlantic rainforests. Our results showed that the interspecific relationships for Synoeca could be described as follows: (S. chalibea + S. virginea) + (S. cyanea + (S. septentrionalis/S. surinama)). Notably, samples of S. septentrionalis and S. surinama collected in the Atlantic Forest were interrelated and may be the result of incomplete lineage sorting and/or mitochondrial introgression among them. Our Bayesian divergence dating analysis revealed recent Plio-Pleistocene diversification in Synoeca. Moreover, our biogeographical analysis suggested an Amazonian origin of Synoeca, with three main dispersal events subsequently occurring during the Plio-Pleistocene. PMID:25738705
Mckay, L. J.; Klokman, V.; Teske, A.
Hydrothermally active sediments at Guaymas Basin are rich in organic substrates and host a wide range of shallow subsurface temperatures: from 3°C to 200°C in the upper 45 centimeters. High temperatures and hydrothermal flow cause upward compression of metabolic zones in Guaymas Basin seafloor sediments. Using push core samples collected by the Alvin submersible (Cruises AT15-40 and 56 in 2008 and 2009) we are investigating thermal structure and carbon and sulfur substrate utilization and their influence on microbial biogeography. As a proxy for viable microbial life total RNA is being extracted from seven high temperature cores that approach, and in three of the cores surpass the upper temperature limit for life at 122°C (Takai et al., 2008). We are using reverse transcription PCR and subsequent pyrosequencing of the V5-V8 region of 16S rRNA to determine key hyperthermophilic archaeal and bacterial groups as well as the upper thermal limit for microbial life in situ. Porewater concentrations of sulfur species and concentrations and isotopic values of carbon species have been investigated in parallel to our high temperature cores. A combination of pyrosequencing data and porewater geochemistry profiles of carbon and sulfur species will help to elucidate the boundaries of life and provide insight into physiological mechanisms under extreme environmental conditions.
吴斌; 林锦国; 崔志勇
Biogeography-Based Optimization (BBO) algorithm is a new kind of optimization algorithm based on biogeography. It is designed based on the migration strategy of species to solve global optimization problem. The migration and mutation operators play the key role in the BBO. Four migration patterns based on the selection model for the islands (which is guiding high emigration rate or high immigration rate) and the scale of migration (single or part variable) are analyzed and discussed. To compare the performance of the four migration operators, 13 experiments are carried out on a set of well-known benchmark global optimization problems. Simulation results show that the partial immigration strategy outperforms other three operators.%生物地理学优化算法(Biogeography-Based Optimization,BBO)是一种模仿物种迁移规律的智能优化算法,其中迁移算子是影响优化效果的关键环节.基于迁移地的选择模式(以迁出率高的栖息地为主导或者以迁入率高的栖息地为主导)和迁移量的规模(单变量和部分变量),提出了BBO算法中可能存在的四种迁移方式.通过对13个经典实例的实验仿真,比较4种迁移算子的优化结果,阐明了产生差异的原因.实验结果表明,迁入主导的部分迁移式算子优化效果最好.
A Townsend Peterson
Parsimony analysis of endemism (PAE) has become a popular analytical approach in efforts to map the biogeography of Mexican biotas. Although attractive, the technique has serious drawbacks that make correct inferences of biogeographic history unlikely, which has been noted amply in the broader literature.El PAE se ha convertido en un método popular en los esfuerzos por resumir, en forma de mapas, la biogeografía de la biota de México. A pesar de su atractivo, la técnica tiene problemas serios...
Plum, C.; Gollner, S.; Martinez Arbizu, P.; Bright, M.
In order to characterize the copepod communitiesassociated with tubeworm and mussel aggregations around ahydrocarbon seep in the Green Canyon of the Gulf of Mexico,diversity, abundance, and community composition were analyzed.Also analyzed were species biogeography and the potentialconnectivity to other chemosynthesis-based habitats.Copepod abundance and biomass were very low amongtubeworms and mussels, with 0.22 to 6.08 individuals per10 cm2 sampled area and 9.02 to 42.43 µg wet weight10 cm2...
Full Text Available Here, insight is provided into the present knowledge on free-living nematodes associated with chemosynthetic environments in the deep sea. It was investigated if the same trends of high standing stock, low diversity, and the dominance of a specialized fauna, as observed for macro-invertebrates, are also present in the nematodes in both vents and seeps.This review is based on existing literature, in combination with integrated analysis of datasets, obtained through the Census of Marine Life program on Biogeography of Deep-Water Chemosynthetic Ecosystems (ChEss.Nematodes are often thriving in the sulphidic sediments of deep cold seeps, with standing stock values ocassionaly exceeding largely the numbers at background sites. Vents seem not characterized by elevated densities. Both chemosynthetic driven ecosystems are showing low nematode diversity, and high dominance of single species. Genera richness seems inversely correlated to vent and seep fluid emissions, associated with distinct habitat types. Deep-sea cold seeps and hydrothermal vents are, however, highly dissimilar in terms of community composition and dominant taxa. There is no unique affinity of particular nematode taxa with seeps or vents.It seems that shallow water relatives, rather than typical deep-sea taxa, have successfully colonized the reduced sediments of seeps at large water depth. For vents, the taxonomic similarity with adjacent regular sediments is much higher, supporting rather the importance of local adaptation, than that of long distance distribution. Likely the ephemeral nature of vents, its long distance offshore and the absence of pelagic transport mechanisms, have prevented so far the establishment of a successful and typical vent nematode fauna. Some future perspectives in meiofauna research are provided in order to get a more integrated picture of vent and seep biological processes, including all components of the marine ecosystem.
Castoe, Todd A; Spencer, Carol L; Parkinson, Christopher L
The western diamondback rattlesnake (Crotalus atrox) is a prominent member of North American desert and semi-arid ecosystems, and its importance extends from its impact on the region's ecology and imagery, to its medical relevance as a large deadly venomous snake. We used mtDNA sequences to identify population genetic structure and historical demographic patterns across the range of this species, and relate these to broader patterns of historical biogeography of desert and semi-arid regions of the southwestern USA and adjacent Mexico. We inferred a Late Pliocene divergence between peninsular and continental lineages of Crotalus, followed by an Early Mid Pleistocene divergence across the continental divide within C. atrox. Within desert regions (Sonoran and Chihuahuan Deserts, Southern Plains, and Tamaulipan Plain) we observed population structure indicating isolation of populations in multiple Pleistocene refugia on either side of the continental divide, which we attempt to identify. Evidence of post-glacial population growth and range expansion was inferred, particularly in populations east of the continental divide. We observed clear evidence of (probably recent) gene flow across the continental divide and secondary contact of haplotype lineages. This recent gene flow appears to be particularly strong in the West-to-East direction. Our results also suggest that Crotalus tortugensis (Tortuga Island rattlesnake) and a population of 'C. atrox' inhabiting Santa Cruz Island (in the Gulf of California) previously suggested to be an unnamed species, are in fact deeply phylogenetically nested within continental lineages of C. atrox. Accordingly, we suggest C. tortugensis and 'C. atrox' from Santa Cruz Island be placed in the synonymy of C. atrox. PMID:16934495
Metfies, Katja; von Appen, Wilken-Jon; Kilias, Estelle; Nicolaus, Anja; Nöthig, Eva-Maria
Information on recent photosynthetic biomass distribution and biogeography of Arctic marine pico-eukaryotes (0.2-3 μm) is needed to better understand consequences of environmental change for Arctic marine ecosystems. We analysed pico-eukaryote biomass and community composition in Fram Strait and large parts of the Central Arctic Ocean (Nansen Basin, Amundsen Basin) using chlorophyll a (Chl a) measurements, automated ribosomal intergenic spacer analysis (ARISA) and 454-pyrosequencing. Samples were collected during summer 2012, the year with the most recent record sea ice minimum. Chl a concentrations were highest in eastern Fram Strait and pico-plankton accounted for 60-90% of Chl a biomass during the observation period. ARISA-patterns and 454-pyrosequencing revealed that pico-eukaryote distribution is closely related to water mass distribution in the euphotic zone of the Arctic Ocean. Phaeocystaceae, Micromonas sp., Dinophyceae and Syndiniales constitute a high proportion of sequence reads, while sequence abundance of autotrophic Phaeocystaceae and mixotrophic Micromonas sp. was inversely correlated. Highest sequence abundances of Phaeocystaceae were observed in the warm Atlantic Waters in Fram Strait, while Micromonas sp. dominated the abundant biosphere in the arctic halocline. Our results are of particular interest considering existing hypotheses that environmental conditions in Nansen Basin might become more similar to the current conditions in Fram Strait. We propose that in response, biodiversity and biomass of pico-eukaryotes in Nansen Basin could resemble those currently observed in Fram Strait in the future. This would significantly alter biogeochemical cycles in a large part of the Central Arctic Ocean. PMID:26895333
Full Text Available Truffles have evolved from epigeous (aboveground ancestors in nearly every major lineage of fleshy fungi. Because accelerated rates of morphological evolution accompany the transition to the truffle form, closely related epigeous ancestors remain unknown for most truffle lineages. This is the case for the quintessential truffle genus Tuber, which includes species with socio-economic importance and esteemed culinary attributes. Ecologically, Tuber spp. form obligate mycorrhizal symbioses with diverse species of plant hosts including pines, oaks, poplars, orchids, and commercially important trees such as hazelnut and pecan. Unfortunately, limited geographic sampling and inconclusive phylogenetic relationships have obscured our understanding of their origin, biogeography, and diversification. To address this problem, we present a global sampling of Tuberaceae based on DNA sequence data from four loci for phylogenetic inference and molecular dating. Our well-resolved Tuberaceae phylogeny shows high levels of regional and continental endemism. We also identify a previously unknown epigeous member of the Tuberaceae--the South American cup-fungus Nothojafnea thaxteri (E.K. Cash Gamundí. Phylogenetic resolution was further improved through the inclusion of a previously unrecognized Southern hemisphere sister group of the Tuberaceae. This morphologically diverse assemblage of species includes truffle (e.g. Gymnohydnotrya spp. and non-truffle forms that are endemic to Australia and South America. Southern hemisphere taxa appear to have diverged more recently than the Northern hemisphere lineages. Our analysis of the Tuberaceae suggests that Tuber evolved from an epigeous ancestor. Molecular dating estimates Tuberaceae divergence in the late Jurassic (~156 million years ago, with subsequent radiations in the Cretaceous and Paleogene. Intra-continental diversification, limited long-distance dispersal, and ecological adaptations help to explain patterns of
Electrical impedance tomography (EIT) is a non-invasive imaging modality which has been actively studied for its industrial as well as medical applications. However, the performance of the inverse algorithms to reconstruct the conductivity images using EIT is often sub-optimal. Several factors contribute to this poor performance, including high sensitivity of EIT to the measurement noise, the rounding-off errors, the inherent ill-posed nature of the problem and the convergence to a local minimum instead of the global minimum. Moreover, the performance of many of these inverse algorithms heavily relies on the selection of initial guess as well as the accurate calculation of a gradient matrix. Considering these facts, the need for an efficient optimization algorithm to reach the correct solution cannot be overstated. This paper presents an oppositional biogeography-based optimization (OBBO) algorithm to estimate the shape, size and location of organ boundaries in a human thorax using 2D EIT. The organ boundaries are expressed as coefficients of truncated Fourier series, while the conductivities of the tissues inside the thorax region are assumed to be known a priori. The proposed method is tested with the use of a realistic chest-shaped mesh structure. The robustness of the algorithm has been verified, first through repetitive numerical simulations by adding randomly generated measurement noise to the simulated voltage data, and then with the help of an experimental setup resembling the human chest. An extensive statistical analysis of the estimated parameters using OBBO and its comparison with the traditional modified Newton–Raphson (mNR) method are presented. The results demonstrate that OBBO has significantly better estimation performance compared to mNR. Furthermore, it has been found that OBBO is robust to the initial guess of the size and location of the boundaries as well as offering a reasonable solution when the a priori knowledge of the conductivity of
Full Text Available Population genetic structure, historical biogeography and historical demography of the alpine toad Scutiger ningshanensis were studied using the combined data mtDNA cytochrome b (cyt b and the mtDNA cytochrome c oxidase subunit I (COI as the molecular markers. This species has high genetic variation. There was a significant genetic differentiation among most populations. Three lineages were detected. The phylogenetic relationship analyses and the SAMOVA (spatial analysis of molecular variance results showed significant phylogeographic structure. 82.15% genetic variation occurred among populations whereas differentiation within populations only contributed 17.85% to the total. Mantel test results showed a significant correlation between the pairwise calculated genetic distance and pairwise calculated geographical distance of the populations (regression coefficient = 0.001286, correlation coefficient = 0.77051, p (rrand≥robs = 0.0185<0.05, indicating the existence of isolation-by-distance pattern of genetic divergence for cyt b + COI sequence, which suggests that the distribution of genetic variation is due to geographical separation rather than natural selection. The population expansion or contraction and genetic differentiation between populations or lineages could be explained by topography and the repetitive uplifts of the Tsinling Mountains and the climatic cycles during the late Pliocene and Pleistocene. S. ningshanensis experienced a rapid population expansion about 40,000 years before present. The current decline in population size was probably caused by anthropogenic disturbance. Current populations of S. ningshanensis are from different refugia though the location of these refugia could not be determined in our study. Topography, climatic changes and repetitive population expansion/contraction together led to the high level of genetic variation in S. ningshanensis. A total of three management units (MUs was determined
Full Text Available Information on recent photosynthetic biomass distribution and biogeography of Arctic marine pico-eukaryotes (0.2-3 μm is needed to better understand consequences of environmental change for Arctic marine ecosystems. We analysed pico-eukaryote biomass and community composition in Fram Strait and large parts of the Central Arctic Ocean (Nansen Basin, Amundsen Basin using chlorophyll a (Chl a measurements, automated ribosomal intergenic spacer analysis (ARISA and 454-pyrosequencing. Samples were collected during summer 2012, the year with the most recent record sea ice minimum. Chl a concentrations were highest in eastern Fram Strait and pico-plankton accounted for 60-90% of Chl a biomass during the observation period. ARISA-patterns and 454-pyrosequencing revealed that pico-eukaryote distribution is closely related to water mass distribution in the euphotic zone of the Arctic Ocean. Phaeocystaceae, Micromonas sp., Dinophyceae and Syndiniales constitute a high proportion of sequence reads, while sequence abundance of autotrophic Phaeocystaceae and mixotrophic Micromonas sp. was inversely correlated. Highest sequence abundances of Phaeocystaceae were observed in the warm Atlantic Waters in Fram Strait, while Micromonas sp. dominated the abundant biosphere in the arctic halocline. Our results are of particular interest considering existing hypotheses that environmental conditions in Nansen Basin might become more similar to the current conditions in Fram Strait. We propose that in response, biodiversity and biomass of pico-eukaryotes in Nansen Basin could resemble those currently observed in Fram Strait in the future. This would significantly alter biogeochemical cycles in a large part of the Central Arctic Ocean.
Smith, Kathlyn M.; Stynder, Deano D.
Elandsfontein (EFT) is a Middle Pleistocene archaeological/paleontological site located in the Western Cape Province of South Africa. The largest herbivore in the assemblage is Loxodonta atlantica zulu, an extinct member of the genus that includes modern African elephants. No Elephas recki specimens were recovered at EFT, despite their common occurrence in other regions of Africa at the same time. Because E. recki and L. atlantica molars are similar in appearance, but the two species are traditionally viewed as dominating different regions of Africa during the Pleistocene, isolated molars may on occasions have been assessed to species level on the basis of geography rather than morphology. The last morphologic evaluation of EFT elephants was conducted in the 1970s, and revisiting this issue with new specimens provides added insight into the evolution of elephants in Africa. Reevaluating morphological characteristics of EFT elephant molars, through qualitative and quantitative description and comparison with Middle Pleistocene E. recki recki, L. atlantica atlantica, and L. atlantica zulu molar morphology, corroborates assessment of EFT elephants as L. a. zulu. Two recently discovered, previously undescribed molars from EFT show that molars of L. a. zulu exhibit greater variation in enamel thickness, lamellar frequency, and occlusal surface morphology than previously reported. An update of the Pleistocene biogeography of Loxodonta and Elephas indicates that fossil remains of both are often found at the same localities in eastern Africa. Their rare co-occurrences in the north and south, however, suggest geographic separation of the two genera in at least some regions of Africa, which may have been based on habitat preference.
Khehra, Baljit Singh; Pharwaha, Amar Partap Singh
Ductal carcinoma in situ (DCIS) is one type of breast cancer. Clusters of microcalcifications (MCCs) are symptoms of DCIS that are recognized by mammography. Selection of robust features vector is the process of selecting an optimal subset of features from a large number of available features in a given problem domain after the feature extraction and before any classification scheme. Feature selection reduces the feature space that improves the performance of classifier and decreases the computational burden imposed by using many features on classifier. Selection of an optimal subset of features from a large number of available features in a given problem domain is a difficult search problem. For n features, the total numbers of possible subsets of features are 2n. Thus, selection of an optimal subset of features problem belongs to the category of NP-hard problems. In this paper, an attempt is made to find the optimal subset of MCCs features from all possible subsets of features using genetic algorithm (GA), particle swarm optimization (PSO) and biogeography-based optimization (BBO). For simulation, a total of 380 benign and malignant MCCs samples have been selected from mammogram images of DDSM database. A total of 50 features extracted from benign and malignant MCCs samples are used in this study. In these algorithms, fitness function is correct classification rate of classifier. Support vector machine is used as a classifier. From experimental results, it is also observed that the performance of PSO-based and BBO-based algorithms to select an optimal subset of features for classifying MCCs as benign or malignant is better as compared to GA-based algorithm.
Alex D Rogers
Full Text Available Since the first discovery of deep-sea hydrothermal vents along the Galápagos Rift in 1977, numerous vent sites and endemic faunal assemblages have been found along mid-ocean ridges and back-arc basins at low to mid latitudes. These discoveries have suggested the existence of separate biogeographic provinces in the Atlantic and the North West Pacific, the existence of a province including the South West Pacific and Indian Ocean, and a separation of the North East Pacific, North East Pacific Rise, and South East Pacific Rise. The Southern Ocean is known to be a region of high deep-sea species diversity and centre of origin for the global deep-sea fauna. It has also been proposed as a gateway connecting hydrothermal vents in different oceans but is little explored because of extreme conditions. Since 2009 we have explored two segments of the East Scotia Ridge (ESR in the Southern Ocean using a remotely operated vehicle. In each segment we located deep-sea hydrothermal vents hosting high-temperature black smokers up to 382.8°C and diffuse venting. The chemosynthetic ecosystems hosted by these vents are dominated by a new yeti crab (Kiwa n. sp., stalked barnacles, limpets, peltospiroid gastropods, anemones, and a predatory sea star. Taxa abundant in vent ecosystems in other oceans, including polychaete worms (Siboglinidae, bathymodiolid mussels, and alvinocaridid shrimps, are absent from the ESR vents. These groups, except the Siboglinidae, possess planktotrophic larvae, rare in Antarctic marine invertebrates, suggesting that the environmental conditions of the Southern Ocean may act as a dispersal filter for vent taxa. Evidence from the distinctive fauna, the unique community structure, and multivariate analyses suggest that the Antarctic vent ecosystems represent a new vent biogeographic province. However, multivariate analyses of species present at the ESR and at other deep-sea hydrothermal vents globally indicate that vent biogeography is more
Full Text Available Many recent researches in island biogeography attempted to disentangle the effects of area per se and “habitat diversity” on species richness. However, the expression “habitat diversity” in this context should be avoided, because habitats can be only recognized by referring to the resources needed by a particular species. What is really measured in such researches is some form of “environmental heterogeneity”. Although habitat heterogeneity can be measured in various ways, most researches in island biogeography simply used the number of biotopes (typically classified as land cover categories. However, not all biotopes have the same surface. On the basis of the area occupied by each land cover category, it is possible to calculate indices of environmental diversity, evenness and dominance, as commonly done in community ecology research. These indices can be used to investigate the role of environmental diversity in determining species richness. We used the tenebrionid beetles inhabiting twenty-five small islands around Sicily (Central Mediterranean to illustrate these concepts. We found that both area per se and environmental heterogeneity contributed to determine species richness. Moreover, we found that the relationship between species richness and environmental homogeneity followed a power function model. This indicates that environmental homogenization may determine a rapid, non linear decline in species richness.
Full Text Available Abstract Background Tribe Fabeae comprises about 380 legume species, including some of the most ancient and important crops like lentil, pea, and broad bean. Breeding efforts in legume crops rely on a detailed knowledge of closest wild relatives and geographic origin. Relationships within the tribe, however, are incompletely known and previous molecular results conflicted with the traditional morphology-based classification. Here we analyse the systematics, biogeography, and character evolution in the tribe based on plastid and nuclear DNA sequences. Results Phylogenetic analyses including c. 70% of the species in the tribe show that the genera Vicia and Lathyrus in their current circumscription are not monophyletic: Pisum and Vavilovia are nested in Lathyrus, the genus Lens is nested in Vicia. A small, well-supported clade including Vicia hirsuta, V. sylvatica, and some Mediterranean endemics, is the sister group to all remaining species in the tribe. Fabeae originated in the East Mediterranean region in the Miocene (23–16 million years ago (Ma and spread at least 39 times into Eurasia, seven times to the Americas, twice to tropical Africa and four times to Macaronesia. Broad bean (V. faba and its sister V. paucijuga originated in Asia and might be sister to V. oroboides. Lentil (Lens culinaris ssp. culinaris is of Mediterranean origin and together with eight very close relatives forms a clade that is nested in the core Vicia, where it evolved c. 14 Ma. The Pisum clade is nested in Lathyrus in a grade with the Mediterranean L. gloeosperma, L. neurolobus, and L. nissolia. The extinct Azorean endemic V. dennesiana belongs in section Cracca and is nested among Mediterranean species. According to our ancestral character state reconstruction results, ancestors of Fabeae had a basic chromosome number of 2n=14, an annual life form, and evenly hairy, dorsiventrally compressed styles. Conclusions Fabeae evolved in the Eastern Mediterranean in the
A. Townsend Peterson
Full Text Available Parsimony analysis of endemism (PAE has become a popular analytical approach in efforts to map the biogeography of Mexican biotas. Although attractive, the technique has serious drawbacks that make correct inferences of biogeographic history unlikely, which has been noted amply in the broader literature.El PAE se ha convertido en un método popular en los esfuerzos por resumir, en forma de mapas, la biogeografía de la biota de México. A pesar de su atractivo, la técnica tiene problemas serios que impiden que las conclusiones resultantes sean las correctas. Estos problemas se han hecho ampliamente evidentes en la literatura sobre este campo.
Huntley, Jerry W; Voelker, Gary
Recent investigations of distributional patterns of Afro-tropical lowland forest species have demonstrated to some degree our overall lack of understanding involving historical diversification patterns. Traditionally, researchers have relied upon two hypotheses, each of which views the lowland forest of Africa in differing roles. The Pleistocene Forest Refuge Hypothesis (PFRH) posits that biogeographic patterns of avian lowland species are explained via allopatric speciation during forest fragmentation cycles in the Pleistocene epoch (c. 1.8Ma-11,700Ka). The Montane Speciation Hypothesis (MSH) countered by suggesting that lowland forests are "evolutionary museums" where species, which originally evolved in montane forest refuge centers, remained without further diversification. Furthermore, investigations have largely regarded widespread, avian species which lack phenotypic variability as biogeographically "uninformative", with regards to historical biogeographic patterns. To test the tenets of these ideas, we investigated the systematics and biogeography of the genus Bleda, whose constituent species are restricted to lowland forest and are lacking in phenotypic variation. Using extracted DNA from 179 individuals, we amplified two mitochondrial genes and three nuclear loci and utilized Bayesian phylogenetic methods and molecular clock dating to develop a time-calibrated phylogeny of Bleda. We used LaGrange to develop an ancestral area reconstruction for the genus. Haplotype networks for three species were generated using Network. We recovered the four currently recognized species of Bleda, plus a monophyletic B. ugandae, a current sub-species which may warrant full species status. We found that the origins of the genus Bleda are estimated to be in the Upper Guinean forests of West Africa, dating to the Miocene (c. 7.5Ma), while the speciation events for the rest of the genus are dated to the Pliocene (c. 5-1.8Ma). Our analyses recovered discrete and highly
Fox, D. L.; Rose, P.
significant negative relationship with paleolatitude. For both analyses, results are similar at the genus levels. In eight species that occur in four or more regions, none demonstrate a statistically significant increase in m1 area with latitude. Thus, despite climatic gradients in the mid-Paleocene that were similar to modern gradients, mammals in the region during the Paleocene appear to violate two essentially canonical biogeographic patterns seen in modern mammals and diverse other organisms, potentially ruling out climate as a long-term control on these patterns. The contrasts between the biogeography of modern and mid-Paleocene mammals in the region could result from distinct community ecology of faunas dominated by extinct “archaic” clades of mammals, ongoing ecological recovery after the Cretaceous-Paleogene extinction, and/or the modern biogeographic patterns being geologically recent or episodic phenomenon and not long-term characteristics of the geographic distribution of mammalian species richness or body size.
PETER LOWENBERG-NETO; Kirstern L. F. Haseyama; Claudio J. B. de Carvalho
In a study on Fanniidae biogeography, Dominguez & Roig-Juñent (2011) argued that the family had a Pangeic origin, Late Jurassic/early Cretaceous (~146 Ma). However, recent literature on Diptera supports that Schizophora radiation occurred during Cenozoic. Fanniidae is a widespread taxon and it was interpreted under the maximum vicariance paradigm; the consequence was an analysis with no alternative hypothesis, but Pangeic origin. We verified that Fanniidae historical narrative was incongruent...
Brooks, Daniel R.
Historical biogeography has recently experienced a significant advancement in three integrated areas. The first is the adoption of an ontology of complexity, replacing the traditional ontology of simplicity, or a priori parsimony; simple and elegant models of the biosphere are not sufficient for explaining the geographical context of the origin of species and their post-speciation movements, producing evolutionary radiations and complex multi-species biotas. The second is the development of a...
Alfaro, Michael E; Karns, Daryl R; Voris, Harold K; Brock, Chad D; Stuart, Bryan L
Homalopsid snakes are widely distributed throughout Southeast Asia and form the ecologically dominant component of the herpetofauna over much of their range. Although they are considered well differentiated from other colubrid lineages, several aspects of their radiation including within-family relationships, temporal patterns of species diversification, and biogeographic history remain under studied. We analyzed sequence data from four genes (three mitochondrial and one nuclear) for 22 species of the Homalopsidae to generate the most comprehensive phylogeny of the family to date. We also estimated divergence times within the family using a model of independent but log-normally distributed rates of evolution in conjunction with two external fossil calibrations. Using this chronogram, we inferred historical patterns of species diversification within the family. Finally, we used previously published sequence data for 172 snake species to test for the monophyly of the Homalopsidae. Phylogenetic analysis reveals strong support for homalopsid monophyly with an estimate age of the crown group of approximately 22 MYA. The family comprises three major clades which all originated 18-20 MY. Lineage through time plots reveal that homalopsids experienced a significantly higher rate of effective cladogenesis in their early history, consistent with a hypothesis of adaptive radiation. We discuss several Miocene and Pliocene paleogeographic factors that might underlie observed patterns of temporal diversification and biogeography. PMID:18182308
Full Text Available Fruit classification is quite difficult because of the various categories and similar shapes and features of fruit. In this work, we proposed two novel machine-learning based classification methods. The developed system consists of wavelet entropy (WE, principal component analysis (PCA, feedforward neural network (FNN trained by fitness-scaled chaotic artificial bee colony (FSCABC and biogeography-based optimization (BBO, respectively. The K-fold stratified cross validation (SCV was utilized for statistical analysis. The classification performance for 1653 fruit images from 18 categories showed that the proposed “WE + PCA + FSCABC-FNN” and “WE + PCA + BBO-FNN” methods achieve the same accuracy of 89.5%, higher than state-of-the-art approaches: “(CH + MP + US + PCA + GA-FNN ” of 84.8%, “(CH + MP + US + PCA + PSO-FNN” of 87.9%, “(CH + MP + US + PCA + ABC-FNN” of 85.4%, “(CH + MP + US + PCA + kSVM” of 88.2%, and “(CH + MP + US + PCA + FSCABC-FNN” of 89.1%. Besides, our methods used only 12 features, less than the number of features used by other methods. Therefore, the proposed methods are effective for fruit classification.
Conti, E; Soltis, D E; Hardig, T M; Schneider, J
The silver saxifrages (Saxifraga sect. Ligulatae Haworth; Saxifragaceae) exhibit remarkable variation of substrate specialization, with strictly calcicole to calcifuge species, as well as life histories which range from semelparity to iteroparity. They occur almost exclusively in the European mountain ranges and display high levels of endemism. Sequences from chloroplast and nuclear ribosomal DNA were obtained to resolve phylogenetic relationships among the silver saxifrages and related taxa and to gain insight into the evolution of substrate specificity, life history, and biogeography. The resulting phylogenies suggested that (1) Saxifraga sect. Ligulatae, as traditionally defined, does not constitute a monophyletic group; (2) lime-secreting hydathodes in calcifuge species apparently represent a secondary nonaptation; (3) semelparity evolved independently two or three times in the silver saxifrages and allied sections, possibly in response to climatic changes that occured during the Pleistocene; and (4) narrow endemics, for example S. cochlearis, likely evolved from the fragmentation of the widespread S. paniculata into refugial populations that became isolated during the glacial maxima of the Pleistocene. PMID:10620412
Nicholas Joseph Matzke
Full Text Available Historical biogeography has been characterized by a large diversity of methods and unresolved debates about which processes, such as dispersal or vicariance, are most important for explaining distributions. A new R package, BioGeoBEARS, implements many models in a common likelihood framework, so that standard statistical model selection procedures can be applied to let the data choose the best model. Available models include a likelihood version of DIVA (“DIVALIKE”, LAGRANGE’s DEC model, and BAYAREA, as well as “+J” versions of these models which include founder-event speciation, an important process left out of most inference methods. I use BioGeoBEARS on a large sample of island and non-island clades (including two fossil clades to show that founder-event speciation is a crucial process in almost every clade, and that most published datasets reject the non-J models currently in widespread use. BioGeoBEARS is open-source and freely available for installation at the Comprehensive R Archive Network at http://CRAN.R-project.org/package=BioGeoBEARS. A step-by-step tutorial is available at http://phylo.wikidot.com/biogeobears.
Rundell, Rebecca J
The endemic diplommatinid land snails (Caenogastropoda: Mollusca) of Belau (Republic of Palau, Micronesia) are an exceptionally diverse group of largely undescribed species distributed among rock and leaf litter habitats on most of Belau's 586 islands. Diplommatinid shell morphology (e.g. shell sculpture) reflects habitat type. In this study, I analysed a subset of the 90 diplommatinid species representing a broad geographical spread of islands in order to reveal the species' phylogenetic relationships and biogeography within the Belau archipelago. Diplommatinid species from the islands of Yap, Pohnpei, Kosrae and Guam are also included in the analysis. One nuclear (28S rRNA) and two mitochondrial (16S rRNA, COI) gene regions comprising 1906bp were used for phylogenetic reconstruction. Results show that (i) the Belau Diplommatinidae are not monophyletic, as Guam and Yap species should be included as part of the radiation, (ii) Pohnpei and Kosrae species are highly divergent from Belau diplommatinids, (iii) there is little evidence for in situ radiation within individual Belau islands, (iv) spined and heavily calcified rock-dwelling species form a well-supported clade, and (v) Belau diplommatinid genera are in need of revision. PMID:18765361
Manconi, Renata; Cadeddu, Barbara; Pronzato, Roberto
A comparative analysis of gemmular architecture adaptive morpho-traits at family level is reported for Metaniidae together with the discovery and description of a new species from the River Mangoky (High Plateau), Madagascar. The new Malagasy species, ascribed to Metania for diagnostic traits of the skeleton and the gemmular architecture, differs from all the other known species of the genus in its unique combination of diagnostic traits. Metania madagascariensis sp. nov. is characterised by encrusting growth form, conulose surface, specialized ectosomal skeleton, alveolate-reticulate choanosomal skeleton, two types of megascleres as smooth oxeas (α) and acanthoxeas (β) ornamented with spines and/or tubercles, one type of microsclere as acanthoxeas with dense spines/tubercles bearing rosettes of microspines at tips; gemmules with or without cage of megascleres and frequently surrounded by microscleres; gemmular theca trilayered with pneumatic layer of fibrous spongin, boletiform (trumpet-like) gemmuloscleres with proximal true rotule large, smooth and with irregular blunt margins, and distal knob-like pseudorotule notably smaller, with a few hooks at the margins. M. madagascariensis belongs to the Afrotropical species group of Metania. Identification keys and an annotated checklist at global level are also provided together with a species-level discussion of Metania focusing on morphology, taxonomy, nomenclature and biogeography. PMID:25781081
Janssens, Steven B; Vandelook, Filip; De Langhe, Edmond; Verstraete, Brecht; Smets, Erik; Vandenhouwe, Ines; Swennen, Rony
Tropical Southeast Asia, which harbors most of the Musaceae biodiversity, is one of the most species-rich regions in the world. Its high degree of endemism is shaped by the region's tectonic and climatic history, with large differences between northern Indo-Burma and the Malayan Archipelago. Here, we aim to find a link between the diversification and biogeography of Musaceae and geological history of the Southeast Asian subcontinent. The Musaceae family (including five Ensete, 45 Musa and one Musella species) was dated using a large phylogenetic framework encompassing 163 species from all Zingiberales families. Evolutionary patterns within Musaceae were inferred using ancestral area reconstruction and diversification rate analyses. All three Musaceae genera - Ensete, Musa and Musella - originated in northern Indo-Burma during the early Eocene. Musa species dispersed from 'northwest to southeast' into Southeast Asia with only few back-dispersals towards northern Indo-Burma. Musaceae colonization events of the Malayan Archipelago subcontinent are clearly linked to the geological and climatic history of the region. Musa species were only able to colonize the region east of Wallace's line after the availability of emergent land from the late Miocene onwards. PMID:26832306
Renz, Jasmin; Markhaseva, Elena L.
Calanoid copepods constitute the most numerous organisms not only in the pelagic realm, but also in the benthic boundary layer, which gives them an important role in the turnover of organic matter in the benthopelagic habitat. During seven expeditions to the South Atlantic and Southern Ocean, the diversity and biogeography of deep-sea benthopelagic calanoid copepods were studied. The communities of calanoids living in the vicinity of the seabed were characterized by high diversity comparable to many pelagic habitats, but low abundance of individuals. Members of the taxon Clausocalanoidea dominated the communities, and within this taxon most individuals belonged to detritivore calanoids characterized by sensory setae on the second maxillae or aetideid copepods. 73% of all genera classified as obligate or predominantly benthopelagic copepods detected during these expeditions were new to science and a vast number of genera and species have been described since then. Comparing the communities of calanoid genera between different regions, the assemblages in the Southern Ocean differed significantly from the Southeast and Southwest Atlantic. A latitudinal diversity gradient could be observed, with highest numbers of genera in the Southwest Atlantic and low numbers at stations in the Southern Ocean. Reviewing the literature, endemism for benthopelagic calanoids appeared to be low on a latitudinal range caused by connectivity in benthopelagic habitats through spreading water masses. However, considering the habitats structuring the water column vertically, a high number of genera are endemic in the benthopelagial and specialized to living within the vicinity of the seabed.
Chen, Zhiqun; Tian, Tian; Gao, Lihong; Tian, Yongqiang
Solar greenhouse is a common facility type used for horticultural crop production in China. However, most solar greenhouse fields have been degraded due to continuous cropping and excessive fertilizer use. Therefore, we investigated solar greenhouse soils covering a wide range of cultivation years and environmental conditions in Round-Bohai Bay-Region to test the effects of cultivation year and biogeography on nutrients, heavy metals, and phthalate acid esters (PAEs). In general, soil pH decreased while soil electrical conductivity (EC), organic matter (OM), total nitrogen (TN), NO3 (-)-N, NH4 (+)-N, mineral nitrogen (MN), Olsen-P, and NH4OAc-K contents increased as time of cultivation increased. However, this trend was influenced by sampling sites. Among sampling sites, Jiangsu showed a relatively low soil pH and high Olsen-P content, while Hebei showed a relatively high soil EC value, NO3 (-)-N, NH4 (+)-N, MN, and NH4OAc-K contents. Liaoning was characterized by relatively high soil OM and TN contents. The nutrient level indexes in evaluation of soil quality on Olsen-P and NH4OAc-K exceeded the standard seriously. The maximum values of the heavy metals Cd, Cu, and Zn were 4.87, 2.78, and 1.15 times higher than the threshold values, respectively. There was a rising trend on the heavy metal contents with the increasing cultivation years, and this trend was significantly influenced by sampling sites. Both Cu and Zn had relative high heavy metal indexes in evaluation of soil pollution. The PAEs were not detected in almost all sampling soils. Overall, the excessive fertilizer application was an important cause of nutrient accumulation and heavy metal pollution, resulting in soil degradation in solar greenhouses. PMID:26996919
目前,虽然有多种智能计算方法用于移动机器人路径规划问题,但在复杂环境下,多数智能计算方法表现出效率低下,结果较差的问题. 提出一种结合基于有效顶点的栅格编码法和改进的生物地理学优化算法的移动机器人路径规划方法,以解决该类问题. 结合已知的环境信息,从精英策略、降维机制和基于惯性算子的迁移操作3方面改进了生物地理学优化算法. 改进算法用于机器人移动路径,与人工蜂群算法、粒子群算法和人工鱼群算法等智能算法进行比较,实验的结果证实改进算法能够更有效地解决复杂环境下机器人路径规划问题.%At present, there are many intelligent computing methods used in mobile robot path planning;however, in complex environments, most of them have low efficiency and poor results. In order to solve such problems, this paper proposes a new method for mobile robot path planning, which combines the grid coding method based on the effective vertex with the improved biogeography-based optimization ( BBO) . On the basis of the environmental infor-mation that has been learned, the BBO is improved in three aspects:elite strategies, dimension reduction mecha-nisms and migration based on inertial operator. The improved BBO is applied in path planning. The method is com-pared with artificial bee colony ( ABC) , particle swarm optimization ( PSO) and artificial fish algorithm ( AFA) . Experiment results show that the improved method can solve the problem of mobile robot path planning in a complex environment more efficiently.
Outbreeding lethality between toxic Group I and nontoxic Group III Alexandrium tamarense spp. isolates: Predominance of heterotypic encystment and implications for mating interactions and biogeography
Brosnahan, Michael L.; Kulis, David M.; Solow, Andrew R.; Erdner, Deana L.; Percy, Linda; Lewis, Jane; Anderson, Donald M.
collected over an 18-year period indicated a leaky pre-mating barrier between ribosomal species (including Groups I and III). Whether the observed selectivity inhibits hybridization in nature is dependent on its mechanism. If the point of selectivity is the induction of gametogenesis, dissimilar ribotypes could interbreed freely, promoting displacement in cases where hybridization is lethal. If instead, selectivity occurs during the adhesion of gamete pairs, it could enable stable co-existence of A. tamarense species. In either case, hybrid inviability may impose a significant obstacle to range expansion. The nested PCR assay developed here is a valuable tool for investigation of interspecies hybridization and its consequences for the global biogeography of these important organisms.
González-Wevar Claudio A
the species. Hence recolonization seems to follow a west to east direction to areas that were progressively deglaciated. Significant genetic differences among Pacific, Atlantic and Falkland/Malvinas Islands populations may be also explained through disparities in their respective glaciological and geological histories. The Falkland/Malvinas Islands, more than representing a glacial refugium for the species, seems to constitute a sink area considering the strong asymmetric gene flow detected from Pacific to Atlantic sectors. These results suggest that historical and contemporary processes represent the main factors shaping the modern biogeography of most shallow marine benthic invertebrates inhabiting the Patagonian Province.
Full Text Available La répartition actuelle du silure glane (Silurus glanis en France et en Europe résulte de la combinaison de facteurs à la fois hydrographiques, climatiques et anthropiques. Des données paléontologiques montrent que l'espèce faisait partie de l'ichtyofaune française (bassin du Rhône avant d'être éliminée par les glaciations. Le réchauffement climatique qui a suivi (10 000 av. JC et l'existence d'interconnexions entre, d'une part, des tributaires de la mer Noire et de la mer Caspienne et d'autre part ceux de la mer Baltique et de la mer du Nord lui ont permis de rapidement coloniser le Nord de l'Europe occidentale. Deux périodes de transplantations-introductions de l'espèce, à but économique, sont identifiées. Une première vague d'introductions hors du bassin danubien semble avoir eu lieu dès le Moyen-Age (lacs de Suisse, suivie par une deuxième période débutant vers 1800, et se poursuivant actuellement. Les effets combinés de ces introductions et des dégradations du milieu d'origine anthropique ont induit un décalage de l'aire de distribution vers le Sud et le Sud-Est de l'Europe (Italie, Espagne, tandis que ne subsistent en Suède, Carélie, Russie et Estonie que des populations relictuelles. Les résultats présentés ici, pourraient aussi concerner d'autres espèces de poissons (Percidés, Cyprinidés, qui, après avoir bénéficié pendant les glaciations des refuges constitués par les bassins de la mer Noire et de la mer Caspienne, ont pu (re- colonisé l'Europe continentale, de manière « naturelle » et avec l'aide de l'Homme. The biogeography of the sheatfish (Silurus glanis results from the combined impacts of hydrogeography, climate and man. Paleontological evidences prove that the species was present in France (Rhône river before the glaciations. The improvement of the climatic conditions (from 10 000 JC and hydrographical interconnexions between tributaries of the Black and Caspian Sea basins, and between
Silva, Luís; Tavares, João; Smith, Clifford W.
Alien plants are a major component of the Azorean vascular flora. We present a general biogeographic analysis of the taxa considered as introduced in the Archipelago. This work results from the construction of a data-base of Azorean plant invaders. Of the 996 taxa recorded for the Azores, 6,6% are considered endemic, 10,2% native, 72.6% alien, and 10,5% to be of uncertain status. The percentage of alien taxa is lowest in the Pteridophyta (26,0%) and highest in the Dicotyledoneae (78,9%). S...
Carstensen, D.W.; Dalsgaard, B.; Svenning, J.-C.; Rahbek, C.; Fjeldså, J.; Sutherland, W.J.; Olesen, Jens M.
between species traits and large-scale species distribution patterns in archipelagos, we use a network approach to classify birds as one of four biogeographical species roles: peripherals, connectors, module hubs, and network hubs. These roles are based upon the position of species within the modular...... distributions at the local community level. We finally discuss how our biogeographical species roles may correspond to the stages of the taxon cycle and other prominent theories of species assembly. © 2013 The Authors....
Ravkin Yury Solomonovich
Full Text Available The article discusses methods and approaches to identify and assess the communication of environmental factors and variability of totals and the character of flora, fauna, vegetation and animal population by the given environment gradients and search of trends inherent in heterogeneity of communities. Attention is paid to the feasibility assessment of connections not only with single factors, but their inseparable combinations - natural and man-made modes. The differences are shown between targeted and value approaches in the researches and connected with this either their greater geographical or ecological bias.
John C. Briggs
Documented extinctions, that have taken place among surrogate taxa during the past 500 years, provide useful information about the extent of recent faunal extinctions and their geographic locations. Species extinctions among terrestrial vertebrates (birds and mammals) and invertebrates (insects and molluscs) have generally taken place in space-restricted habitats, primarily oceanic islands. An extinction pathway leads from the high diversity tropics to less diverse, peripheral habitats that f...
John C. Briggs
Full Text Available Documented extinctions, that have taken place among surrogate taxa during the past 500 years, provide useful information about the extent of recent faunal extinctions and their geographic locations. Species extinctions among terrestrial vertebrates (birds and mammals and invertebrates (insects and molluscs have generally taken place in space-restricted habitats, primarily oceanic islands. An extinction pathway leads from the high diversity tropics to less diverse, peripheral habitats that function as extinction traps. The pace along the extinction pathway is gradual and its function is similar to a pathway which has been observed in the marine environment. Overall, the low incidence of recent extinctions appears to be a continuation of the minimal rates that were characteristic of the Pleistocene epoch. Thousands of species, represented by small populations on the pathways to extinction, can still be rescued if there is sufficient interest in doing so.
Full Text Available In a study on Fanniidae biogeography, Dominguez & Roig-Juñent (2011 argued that the family had a Pangeic origin, Late Jurassic/early Cretaceous (~146 Ma. However, recent literature on Diptera supports that Schizophora radiation occurred during Cenozoic. Fanniidae is a widespread taxon and it was interpreted under the maximum vicariance paradigm; the consequence was an analysis with no alternative hypothesis, but Pangeic origin. We verified that Fanniidae historical narrative was incongruent with the Gondwana sequential break-up. A second analysis, assuming the Fanniidae origin during early Paleocene (65 Ma, showed congruence with recent geological events and with the Muscidae diversification, a closely related Muscoidea family. Our hypothesis suggests that the Fanniidae originated in Paleogene and they were affected by few events of vicariance and several expansions during Cenozoic.En un estudio sobre biogeografía de Fanniidae, Domínguez & Roig-Juñent (2011 argumentaron que la familia era de origen Pangeico, Jurásico superior/Cretáceo inferior (~146 Ma. Sin embargo, literatura reciente sobre Diptera, confirma que la radiación de Schizophora ocurrió durante el Cenozoico. Fanniidae es un taxón ampliamente distribuido y fue interpretado bajo el paradigma de máxima vicarianza; la consecuencia, fue un análisis sin hipótesis alternativas, pero de origen pangeico. Nosotros verificamos que la narrativa histórica de Fanniidae es incongruente con la quiebra secuencial de Gondwana. Un segundo análisis, asumiendo el origen de Fanniidae durante el Paleoceno inferior (65 Ma, mostró congruencia con eventos geológicos recientes y con la diversificación de Muscidae, una familia de Muscoidea próximamente relacionada. Nuestra hipótesis sugiere que Fanniidae se originó en el Paleógeno y fueron afectados por pocos eventos de vicarianza y muchas expansiones durante el Cenozoico.
Marcela L. Monné
Full Text Available A revisão do gênero sul-americano Coccoderus é apresentada. Dez espécies são reconhecidas, das quais C. sexguttatus, considerada sinônimo de C. amazonicus, é revalidada. São fornecidas chave de identificação e ilustrações das espécies. A análise cladística, com 31 caracteres morfológicos e 12 táxons, resultou em dois cladogramas igualmente mais parcimoniosos e em ambos a monofilia de Coccoderus é suportada por cinco sinapomorfias. São incluídos notas sobre biogeografia e mapas de distribuição. Sete espécies ocorrem em simpatria no Cerrado, das quais duas espécies também ocorrem na Floresta Amazônica e duas na Mata Atlântica. Duas espécies ocorrem apenas na Floresta Amazônica e uma espécie nas matas orientais das encostas dos Andes.A revision of the South American genus Coccoderus is presented. Ten species are recognized, of which C. sexguttatus, previously considered a synonym of C. amazonicus, is reinstated. Key to identification and illustrations of the species are added. The cladistic analysis, based on 31 morphological characters and 12 taxa, resulted in two equally most parsimonious cladograms and in both the monophyly of Coccoderus is supported by five synapomorphies. Notes on biogeography and maps of distribution are provided. Seven species occurs in sympatry on Cerrado, of which two species also occur in the Amazon Forest and two on the Atlantic Forest. Two species occurs only in the Amazon Forest and one species in the oriental forests of the Andes.
Revision and biogeography of the Neotropical dung beetle genus Scybalophagus (Coleoptera: Scarabaeidae Revisión y Biogeografía del género neotropical de escarabajos estercoleros Scybalophagus (Coleoptera: Scarabaeidae
Federico Carlos Ocampo
Full Text Available The South American genus Scybalophagus Martínez is comprehensively revised. The genus now includes five species, distributed in Argentina, Chile, Bolivia and Peru. All species are redescribed and diagnostic characters are provided along with illustrations of each species. Lectotypes are designated for Canthon lacordairei Laporte, 1840 (now Scybalophagus lacordairei and Canthon rugosus Blanchard, 1845 (now Scybalophagus rugosus. Scybalophagus zumpti (Frey, 1963 (=Epirinus zumpti Frey is now considered a junior synonym of S. rugosus (Blanchard. The biogeography of the genus and of each species is discussed and predictive distributions, based on environmental niche modeling, are provided for all species. Information on the biology and natural history of Scybalophagus species is discussed.El género suramericano Scybalophagus Martínez es revisado exhaustivamente. El género ahora incluye cinco especies distribuidas en Argentina, Chile, Bolivia y Perú. Se redescriben todas las especies y se proveen caracteres diagnósticos junto con ilustraciones para cada especie. Se designan lectotipos para Canthon lacordairei Laporte, 1840 (ahora Scybalophagus lacordairei y Canthon rugosus Blanchard, 1845 (ahora S. rugosus. Scybalophagus zumpti (Frey 1963 (=Epirinus zumpti Frey es ahora considerado un sinónimo junior de S. rugosus (Blanchard. La Biogeografía del género y cada especie es discutida y se presentan distribuciones potenciales, basadas en modelos de nicho ecológico, para todas las especies. Se discute la información sobre la biología e historia natural de las especies de Scybalophagus.
Gilberto E Flores
Full Text Available We spend the majority of our lives indoors where we are constantly exposed to bacteria residing on surfaces. However, the diversity of these surface-associated communities is largely unknown. We explored the biogeographical patterns exhibited by bacteria across ten surfaces within each of twelve public restrooms. Using high-throughput barcoded pyrosequencing of the 16 S rRNA gene, we identified 19 bacterial phyla across all surfaces. Most sequences belonged to four phyla: Actinobacteria, Bacteriodetes, Firmicutes and Proteobacteria. The communities clustered into three general categories: those found on surfaces associated with toilets, those on the restroom floor, and those found on surfaces routinely touched with hands. On toilet surfaces, gut-associated taxa were more prevalent, suggesting fecal contamination of these surfaces. Floor surfaces were the most diverse of all communities and contained several taxa commonly found in soils. Skin-associated bacteria, especially the Propionibacteriaceae, dominated surfaces routinely touched with our hands. Certain taxa were more common in female than in male restrooms as vagina-associated Lactobacillaceae were widely distributed in female restrooms, likely from urine contamination. Use of the SourceTracker algorithm confirmed many of our taxonomic observations as human skin was the primary source of bacteria on restroom surfaces. Overall, these results demonstrate that restroom surfaces host relatively diverse microbial communities dominated by human-associated bacteria with clear linkages between communities on or in different body sites and those communities found on restroom surfaces. More generally, this work is relevant to the public health field as we show that human-associated microbes are commonly found on restroom surfaces suggesting that bacterial pathogens could readily be transmitted between individuals by the touching of surfaces. Furthermore, we demonstrate that we can use high-throughput analyses of bacterial communities to determine sources of bacteria on indoor surfaces, an approach which could be used to track pathogen transmission and test the efficacy of hygiene practices.
Leigh, EG; O'Dea, A; Vermeij, GJ
About 3million years ago (Ma), the Isthmus of Panama joined the Americas, forming a land bridge over which inhabitants of each America invaded the other-the Great American Biotic Interchange. These invasions transformed land ecosystems in South and Middle America. Humans invading from Asia over 12000years ago killed most mammals over 44kg, again transforming tropical American ecosystems. As a sea barrier, the isthmus induced divergent environmental change off its two coasts-creating contrasti...
Baker, William J.; Eiserhardt, Wolf L.; Kissling, W. Daniel;
Recent biogeographic and ecoinformatic studies of palms provide a global context for the spatio-temporal evolution of palms and the tropical rain forests that they inhabit. Palms display high rain forest niche conservatism, with >90% of species occurring in this biome. The global distribution of...... clades and species richness is highly structured, suggestive of complex, differentiated patterns of evolutionary drivers. Macroecological studies show that palm species richness is globally contingent on climatic variables typical of the humid tropics, while island palm floras are also influenced by area...... for our understanding of rain forests because fossil evidence for this biome prior to the Palaeocene is weak. Lineage diversification in palms has proceeded in a constant manner from 100 Ma at least until the Miocene, conforming to the museum model of diversification. Since the Miocene...
Burrett, Clive; Richardson, Robert
The biogeographic patterns of Cambrian trilobites are almost impossible to explain on an Early Palaeozoic Pangaea but may be explained by relative movements of several continental blocks separated by wide ocean basins. Realms, regions, provinces and sub-provinces are recognised by progressively agglomerating 450 faunal lists, based on 1371 genera, distributed through eleven time segments. The agglomerating method proposed, is a simple one that may be performed by hand or computer and provides Medial Cambrian results similar to those of Jell (1974) who used principal components and cluster analyses. Simplified results are obtained when time segments are combined or when only the largest list from each 10° (lat. × long.) tessera is used or when only illustrated papers are used or when only lists containing ⩾ 3, 5 or 10 genera are used. The program was also run with all of the presumably planktonic miomerids removed resulting in smaller, better defined provinces with few links between tectonic blocks. The number of polymerid-only realms is three in Albertella Zone times, four in Glossopleura Zone and Eluinia/Conaspis Zone times and five in all other time segments. The average five realms recognised tend to be restricted to one (or rarely two) of the major tectonic blocks: America (excluding Boston and maritime Canada), Europe (including Morocco), Siberia, China and Australia. The existence of the American realm in Argentina through most of the Cambrian and the unlikelihood of a dismembered Gondwanaland necessitates using the latitudinal control hypothesis of Palmer (1972). This hypothesis places the European realm in high palaeolatitudes, the American realm in low palaeolatitudes in the Southern Hemisphere, the Australian realm in low palaeolatitudes in the Northern Hemisphere and the Siberian realm in temperate palaeolatitudes in the Southern Hemisphere. When the miomerids are included, connections between the peripheral ocean-facing regions of one tectonic block are frequently strong with other tectonic blocks. Some of these connections are preserved even when the miomerids are excluded suggesting that many polymerids were pelagic. Connections between Siberia and ocean-facing regions of North America are particularly strong throughout most of the Cambrian.
Read, Daniel S; Gweon, Hyun S; Bowes, Michael J; Newbold, Lindsay K; Field, Dawn; Bailey, Mark J; Griffiths, Robert I
Lotic ecosystems such as rivers and streams are unique in that they represent a continuum of both space and time during the transition from headwaters to the river mouth. As microbes have very different controls over their ecology, distribution and dispersion compared with macrobiota, we wished to explore biogeographical patterns within a river catchment and uncover the major drivers structuring bacterioplankton communities. Water samples collected across the River Thames Basin, UK, covering the transition from headwater tributaries to the lower reaches of the main river channel were characterised using 16S rRNA gene pyrosequencing. This approach revealed an ecological succession in the bacterial community composition along the river continuum, moving from a community dominated by Bacteroidetes in the headwaters to Actinobacteria-dominated downstream. Location of the sampling point in the river network (measured as the cumulative water channel distance upstream) was found to be the most predictive spatial feature; inferring that ecological processes pertaining to temporal community succession are of prime importance in driving the assemblages of riverine bacterioplankton communities. A decrease in bacterial activity rates and an increase in the abundance of low nucleic acid bacteria relative to high nucleic acid bacteria were found to correspond with these downstream changes in community structure, suggesting corresponding functional changes. Our findings show that bacterial communities across the Thames basin exhibit an ecological succession along the river continuum, and that this is primarily driven by water residence time rather than the physico-chemical status of the river. PMID:25238398
Eger, J.L.; Mitchell, L
Sept des 17 familles de chauve-souris sont représentées sur l'île de Madagascar, dont une, est endémique, le #Myzopodidae$. Trois genres, #Pteropus$, #Emballonura$ et #Mormopterus$, sont présents à Madagascar et en Asie mais pas en Afrique. Deux autres genres, #Eidolon$ et #Triaenops$, existent à Madagascar et en Afrique, mais sont absents en Asie. Parmi les 28 espèces des chauve-souris malgaches, dont il existe des spécimens, 18 sont endémiques. Sur la base de leur distribution et des analys...
Larick, Roy; Ciochon, Russell L
Island Southeast Asia covers Eurasia's tropical expanse of continental shelf and active subduction zones. Cutting between island landmasses, Wallace's Line separates Sunda and the Eastern Island Arc (the Arc) into distinct tectonic and faunal provinces. West of the line, on Sunda, Java Island yields many fossils of Homo erectus. East of the line, on the Arc, Flores Island provides one skeleton and isolated remains of Homo floresiensis. Luzon Island in the Philippines has another fossil hominin. Sulawesi preserves early hominin archeology. This insular divergence sets up a unique regional context for early hominin dispersal, isolation, and extinction. The evidence is reviewed across three Pleistocene climate periods. Patterns are discussed in relation to the pulse of global sea-level shifts, as well as regional geo-tectonics, catastrophes, stegodon dispersal, and paleogenomics. Several patterns imply evolutionary processes typical of oceanic islands. Early hominins apparently responded to changing island conditions for a million-and-a-half years, likely becoming extinct during the period in which Homo sapiens colonized the region. PMID:26478140
Lee, J. A.; Francis, C. A.
The largest estuary on the west coast of North America, San Francisco Bay is an ecosystem of enormous biodiversity, and also enormous human impact. The benthos has experienced dredging, occupation by invasive species, and over a century of sediment input as a result of hydraulic mining. Although the Bay's great cultural and ecological importance has inspired numerous surveys of the benthic macrofauna, to date there has been almost no investigation of the microbial communities on the Bay floor. An understanding of those microbial communities would contribute significantly to our understanding of both the biogeochemical processes (which are driven by the microbiota) and the physical processes (which contribute to microbial distributions) in the Bay. Here, we present the first broad survey of bacterial and archaeal taxa in the sediments of the San Francisco Bay. We conducted 16S rRNA community sequencing of bacteria and archaea in sediment samples taken bimonthly for one year, from five sites spanning the salinity gradient between Suisun and Central Bay, in order to capture the effect of both spatial and temporal environmental variation on microbial diversity. From the same samples we also conducted deep sequencing of a nitrogen-cycling functional gene, nirS, allowing an assessment of evolutionary diversity at a much finer taxonomic scale within an important and widespread functional group of bacteria. We paired these sequencing projects with extensive geochemical metadata as well as information about macrofaunal distribution. Our data reveal a diversity of distinct biogeographical patterns among different taxa: clades ubiquitous across sites; clades that respond to measurable environmental drivers; and clades that show geographical site-specificity. These community datasets allow us to test the hypothesis that salinity is a major driver of both overall microbial community structure and community structure of the denitrifying bacteria specifically; and to assess whether patterns of diversity observed at the broadest of taxonomic scales also apply to patterns observed within a single extremely diverse gene (nirS). In sum, this project provides a first look at the forces driving the migration and selection of microbial communities in San Francisco Bay.
Vishnivetskaya, Tatiana A [ORNL; Kathariou, Sophia [North Carolina State University; Tiedje, James M. [Michigan State University, East Lansing
Abstract. Bacteria of the genus Exiguobacterium are low G + C, Gram-positive facultative anaerobes that have been repeatedly isolated from ancient Siberian permafrost. In addition, Exiguobacterium spp. have been isolated from markedly diverse sources, including Greenland Glacial ice, hot springs at Yellowstone National Park, the rhizosphere of plants, and the environment of food processing plants. Strains of this hereto little known bacterium that have been retrieved from such different (and often extreme) environments are worthy of attention as they are likely to be specifically adapted to such environments and to carry variations in the genome which may correspond to psychrophilic and thermophilic adaptations. However, comparative genomic investigations of Exiguobacterium spp. from different sources have been limited. In this study, we employed different molecular approaches for the comparative analysis of 24 isolates from markedly diverse environments including ancient Siberian permafrost and hot springs at Yellowstone National Park. Pulsed-field gel electrophoresis (PFGE) with I-CeuI (an intron-encoded endonuclease), AscI and NotI were optimized for the determination of genomic fingerprints of nuclease-producing isolates. The application of a DNA macroarray for 82 putative stress-response genes yielded strain-specific hybridization profiles. Cluster analyses of 16S rRNA gene sequence data, PFGE I-CeuI restriction patterns and hybridization profiles suggested that Exiguobacterium strains formed two distinct divisions that generally agreed with temperature ranges for growth. With few exceptions (e.g., Greenland ice isolate GIC31), psychrotrophic and thermophilic isolates belonged to different divisions.
Full Text Available Biodiversity and biogeographic studies comparing the distribution patterns of benthic marine organisms across the Iberian Atlantic and Mediterranean waters are scarce. The Pycnogonida (sea spiders are a clear example of both endemicity and diversity, and are considered a key taxon to study and monitor biogeographic and biodiversity patterns. This is the first review that compiles data about abundance and diversity of Iberian pycnogonids and examines their biogeographic patterns and bathymetric constraints using GIS tools. A total of 17,762 pycnogonid records from 343 localities were analyzed and were found to contain 65 species, 21 genera and 12 families. Achelia echinata and Ammothella longipes (family Acheliidae were the most abundant comprising ~80% of the total records. The Acheliidae is also the most speciose in Iberian waters with 15 species. In contrast, the family Nymphonidae has 7 species but is significantly less abundant (<1% of the total records than Acheliidae. Species accumulation curves indicate that further sampling would increase the number of Iberian species records. Current sampling effort suggests that the pycnogonid fauna of the Mediterranean region may be richer than that of the Atlantic. The Strait of Gibraltar and the Alboran Sea are recognized as species-rich areas that act as buffer zones between the Atlantic and Mediterranean boundaries. The deep waters surrounding the Iberian Peninsula are poorly surveyed, with only 15% of the sampling sites located below 1000 m. Further deep-water sampling is needed mainly on the Iberian Mediterranean side.
Floeter, S.R.; Rocha, L.A.; Robertson, D.R.; Joyeux, J.C.; Smith-Vaniz, W.F.; Wirtz, P.; Edwards, A.J.; Barreiros, J.P.; Ferreira, C.E.L.; Gasparini, J.L.; Brito, A.; Falcon, J.M.; Bowen, B.W.; Bernardi, G.
Aim: To understand why and when areas of endemism (provinces) of the tropical Atlantic Ocean were formed, how they relate to each other, and what processes have contributed to faunal enrichment. Location: Atlantic Ocean. Methods: The distributions of 2605 species of reef fishes were compiled for 25 areas of the Atlantic and southern Africa. Maximum-parsimony and distance analyses were employed to investigate biogeographical relationships among those areas. A collection of 26 phylogenies of various Atlantic reef fish taxa was used to assess patterns of origin and diversification relative to evolutionary scenarios based on spatio-temporal sequences of species splitting produced by geological and palaeoceanographic events. We present data on faunal (species and genera) richness, endemism patterns, diversity buildup (i.e. speciation processes), and evaluate the operation of the main biogeographical barriers and/or filters. Results: Phylogenetic (proportion of sister species) and distributional (number of shared species) patterns are generally concordant with recognized biogeographical provinces in the Atlantic. The highly uneven distribution of species in certain genera appears to be related to their origin, with highest species richness in areas with the greatest phylogenetic depth. Diversity buildup in Atlantic reef fishes involved (1) diversification within each province, (2) isolation as a result of biogeographical barriers, and (3) stochastic accretion by means of dispersal between provinces. The timing of divergence events is not concordant among taxonomic groups. The three soft (non-terrestrial) inter-regional barriers (mid-Atlantic, Amazon, and Benguela) clearly act as 'filters' by restricting dispersal but at the same time allowing occasional crossings that apparently lead to the establishment of new populations and species. Fluctuations in the effectiveness of the filters, combined with ecological differences among provinces, apparently provide a mechanism for much of the recent diversification of reef fishes in the Atlantic. Main conclusions: Our data set indicates that both historical events (e.g. Tethys closure) and relatively recent dispersal (with or without further speciation) have had a strong influence on Atlantic tropical marine biodiversity and have contributed to the biogeographical patterns we observe today; however, examples of the latter process outnumber those of the former. ?? 2007 The Authors.
The distribution of the Ordovician (~444–488 Ma) rhynchonelliform brachiopods was investigated for identification of biogeographic provinces and areas constituting focal points for taxon speciation, and to describe the faunas and biodiversity associated with the provinces, palaeoplates, and terra...
Weissleader, L.S.; Gilinsky, N.L.; Ross, R.M.; Cronin, T. M.
Bottom lagoonal sediment samples from 12 islands and atolls yielded >70 species representing >32 ostracode genera. All or most samples from a particular lagoon generally form distinct subgroups (Jaccard =0.45-0.50). At lower levels, 5 groups delineate faunal regions within Micronesia: the Gilbert Islands (Onotoa) in the SE part of the region, the N Marshall Islands (Enewetak, Rongelap, Bikini), the SE Marshall Islands (Kwajalein, Jaluit, Majuro, Arno), the Marianas and Caroline Islands (Guam, Truk, Pohnpei) and Pingelap. Pingelap, Kwajalein and Onotoa have the highest species richness (S=32-42) and Shannon-Wiener diversity values (H(S)=2.62-3.02) in the study area. Enewetak, Jaluit, Majuro and Arno show lower values (S=23-27, H(S)=2.29-2.70). Of the ostracode species living in Micronesia, 64.3% have Indo-West Pacific affinities, 7.1% are circumtropical, 5.7% have East Pacific-Caribbean affinities, 11.4% are endemic to Micronesia, and 11.4% have unknown affinities. If the SE Asian region is a primary species-source, results show that each Micronesian lagoon is equally likely to be colonized by dispersal from the source region, despite differences in distance from a hypothetical source. However, each lagoon has a distinct ostracode assemblage, probably the result of unique history of random colonization events, local extinctions and environmental disturbances. -from Authors
Fei, Songlin; Liang, Liang; Paillet, Frederick L.;
of American chestnut [C. dentata (Marsh.) Borkh.] by incorporating blight-resistant genes from Asiatic species. Location North America, Europe and East Asia. Methods General chestnut biology was reviewed on the basis of published literature and field observations. Chestnut distributions were......Aim Chestnuts (Castanea spp.) are ecologically and economically important species. We studied the general biology, distribution and climatic limits of seven chestnut species from around the world. We provided climatic matching of Asiatic species to North America to assist the range-wide restoration...... of chestnut distribution. Climatic spaces of different species overlap with one another to different degrees, but strong similarities are shown especially between Chinese species and American species. Climatic envelope matching suggested that large areas in eastern North America have a favourable...
The existing literature on the Odonata inhabiting the three large divisions of the Pacific Ocean (Micronesia, Melanesia, Polynesia) is revised taking into consideration earlier discussions on the species origin, historical faunistic records, various palaeogeographical models proposed for the area, general data on the biology and ecology of this insect order. Special emphasis is paid on the incomplete data set for the region and inconsistency of the exploration of this vast area. The taxonomy ...
Burridge, A.K.; Goetze, E.; Raes, N.; Huisman, J.; Peijnenburg, K.T.C.A.
Background Shelled pteropods are planktonic gastropods that are potentially good indicators of the effects of ocean acidification. They also have high potential for the study of zooplankton evolution because they are metazoan plankton with a good fossil record. We investigated phenotypic and genetic variation in pteropods belonging to the genus Cuvierina in relation to their biogeographic distribution across the world’s oceans. We aimed to assess species boundaries and to reconstruct their ev...
Revisão sistemática, análise cladística e biogeografia dos gêneros Tribotropis e Hypselotropis (Coleoptera, Anthribidae, Anthribinae, Ptychoderini Systematic revision, cladistic analysis and biogeography of the genera Tribotropis and Hypselotropis (Coleoptera, Anthribidae, Anthribinae, Ptychoderini
José Ricardo M. Mermudes
comb. nov.; e H. vittata (Kirsch, 1889 comb. nov.. A key to species, illustrations and maps of distribution are provided. The biogeography based on patterns of distribution of the species are discussed.
Davis, Charles Cavender; Ellison, Aaron M.; Butler, Elena D.; Hicks, Emily Jean; Calie, Patrick J.; Bell, Charles D.; Naczi, Robert F. C.
The carnivorous plant family Sarraceniaceae comprises three genera of wetland-inhabiting pitcher plants: Darlingtonia in the northwestern United States, Sarracenia in eastern North America, and Heliamphora in northern South America. Hypotheses concerning the biogeographic history leading to this unusual disjunct distribution are controversial, in part because genus- and species-level phylogenies have not been clearly resolved. Here, we present a robust, species-rich phylogeny of Sarraceniacea...
Ellison, Aaron M; Butler, Elena D; Hicks, Emily Jean; Naczi, Robert F C; Calie, Patrick J; Bell, Charles D; Davis, Charles C
The carnivorous plant family Sarraceniaceae comprises three genera of wetland-inhabiting pitcher plants: Darlingtonia in the northwestern United States, Sarracenia in eastern North America, and Heliamphora in northern South America. Hypotheses concerning the biogeographic history leading to this unusual disjunct distribution are controversial, in part because genus- and species-level phylogenies have not been clearly resolved. Here, we present a robust, species-rich phylogeny of Sarraceniaceae based on seven mitochondrial, nuclear, and plastid loci, which we use to illuminate this family's phylogenetic and biogeographic history. The family and genera are monophyletic: Darlingtonia is sister to a clade consisting of Heliamphora+Sarracenia. Within Sarracenia, two clades were strongly supported: one consisting of S. purpurea, its subspecies, and S. rosea; the other consisting of nine species endemic to the southeastern United States. Divergence time estimates revealed that stem group Sarraceniaceae likely originated in South America 44-53 million years ago (Mya) (highest posterior density [HPD] estimate = 47 Mya). By 25-44 (HPD = 35) Mya, crown-group Sarraceniaceae appears to have been widespread across North and South America, and Darlingtonia (western North America) had diverged from Heliamphora+Sarracenia (eastern North America+South America). This disjunction and apparent range contraction is consistent with late Eocene cooling and aridification, which may have severed the continuity of Sarraceniaceae across much of North America. Sarracenia and Heliamphora subsequently diverged in the late Oligocene, 14-32 (HPD = 23) Mya, perhaps when direct overland continuity between North and South America became reduced. Initial diversification of South American Heliamphora began at least 8 Mya, but diversification of Sarracenia was more recent (2-7, HPD = 4 Mya); the bulk of southeastern United States Sarracenia originated co-incident with Pleistocene glaciation, <3 Mya. Overall, these results suggest climatic change at different temporal and spatial scales in part shaped the distribution and diversity of this carnivorous plant clade. PMID:22720090
Naff, C S; Darcy, J L; Schmidt, S K
Numerous studies have shown that snow can contain a diverse array of algae known as 'snow algae'. Some reports also indicate that parasites of algae (e.g. chytrids) are also found in snow, but efforts to phylogenetically identify 'snow chytrids' have not been successful. We used culture-independent molecular approaches to phylogenetically identify chytrids that are common in long-lived snowpacks of Colorado and Europe. The most remarkable finding of the present study was the discovery of a new clade of chytrids that has representatives in snowpacks of Colorado and Switzerland and cold sites in Nepal and France, but no representatives from warmer ecosystems. This new clade ('Snow Clade 1' or SC1) is as deeply divergent as its sister clade, the Lobulomycetales, and phylotypes of SC1 show significant (P snow chytrids were phylogenetically shown to be in the order Rhizophydiales, a group with known algal parasites and saprotrophs. We suggest that these newly discovered snow chytrids are important components of snow ecosystems where they contribute to snow food-web dynamics and the release of nutrients due to their parasitic and saprotrophic activities. PMID:23551529
Mechanisms for the generation of biodiversity in species-rich biomes such as rain forests remain unclear. Molecular phylogenies using DNA sequence data, calibrated with a temporal dimension offer a means of addressing this question, enabling the testing of different hypotheses on biogeographic histories and causes of diversification. Manilkara is a genus of trees in the Sapotaceae consisting of ~79 species distributed throughout the tropics (30 South and Central American, 35 African and 14 So...
Boucher, Florian C; Thuiller, Wilfried; Davies, T Jonathan; Lavergne, Sébastien
Recent debate on whether climatic niches are conserved through time has focused on how phylogenetic niche conservatism can be measured by deviations from a Brownian motion model of evolutionary change. However, there has been no evaluation of this methodological approach. In particular, the fact that climatic niches are usually obtained from distribution data and are thus heavily influenced by biogeographic factors has largely been overlooked. Our main objective here was to test whether patterns of climatic niche evolution that are frequently observed might arise from neutral dynamics rather than from adaptive scenarios. We developed a model inspired by neutral biodiversity theory, where individuals disperse, compete, and undergo speciation independently of climate. We then sampled the climatic niches of species according to their geographic position and showed that even when species evolve independently of climate, their niches can nonetheless exhibit evolutionary patterns strongly differing from Brownian motion. Indeed, climatic niche evolution is better captured by a model of punctuated evolution with constraints due to landscape boundaries, two features that are traditionally interpreted as evidence for selective processes acting on the niche. We therefore suggest that deviation from Brownian motion alone should not be used as evidence for phylogenetic niche conservatism but that information on phenotypic traits directly linked to physiology is required to demonstrate that climatic niches have been conserved through time. PMID:24739191
Full Text Available Apresenta-se um breve panorama das principais teorias biogeográficas, mostrando como o conhecimento acumulado por naturalistas viajantes foi responsável por seu teste e eventual rejeição. Enfatiza-se a importância de se conhecerem os relatos dos antigos viajantes e naturalistas, para avaliar o quão severa foi a ação antrópica sobre a distribuição geográfica de alguns grupos de vertebrados.This article shows a brief panorama of the most important biogeographic theories and how scientific knowledge rendered by travelling naturalists plays a relevant role in testing and sometimes rejecting some of these theories. The article also emphasizes the importance of becoming familiar with past travellers' and naturalists' reports in order to understand how severe human action was in geographically distributing some vertebrate groups.
Full Text Available Abstract Five taxa of the Mustelidae family now occur on the Mediterranean islands: the pine marten, Martes martes L., 1758, distributed on some of the Balearic and Tyrrhenian islands, the stone marten, M. foina Erxleben, 1777, which occurs on many islands of the basin, the badger, Meles meles Brisson, 1762, that has been only reported from some Greek islands, the weasel, Musteln nivalis L., 1766, common to many of the islands, and the otter, Lutra lutra L., 1758, recorded from the Greek islands. During Late Pleistocene times, only few carnivores seem to have occurred, however, on these islands and none is referable to the species that are present today. Paleontological evidence attests only to the occurrence of endemic elements, most of which were related to the Lutrinae subfamily. Apart from L. lutra, the absence during Late Pleistocene and Early Holocene of the continental species present today suggests that these carnivores are allochthonous. They were imported by man, for various purposes, probably since prehistorical and/or early historical times. Riassunto Biogeografia quaternaria della famiglia Mustelidae nelle isole del Mediterraneo - La distribuzione attuale dei rappresentanti della famiglia Mustelidae nelle isole mediterranee interessa esclusivamente cinque specie: la martora, Martes martes L., 1758, presente su alcune isole baleariche e tirreniche, la faina, M. foina Erxleben, 1777, diffusa in varie isole del Mediterraneo, il tasso, Meles meles Brisson, 1762, che viene solo segnalato per alcune isole greche, la donnola, Mustela nivalis L., 1766, che interessa molte isole del bacino e la lontra, Lutra lutra L., 1758, nota solamente per alcune isole greche. Nel corso del Pleistocene altre forme di mustelidi hanno comunque interessato queste isole e nessuna di esse può essere riferita tassonomicamente a quelle oggi presenti. Il Quaternario delle isole mediterranee è infatti esclusivamente caratterizzato dalla presenza di mustelidi endemici, appartenenti per la maggior parte alla sottofamiglia Lutrinae. Fatta eccezione per L. lutra, l'assenza durante il tardo Pleistocene e l'Olocene antico dei mustelidi continentali, oggi presenti sulle isole, suggerisce un'origine antropocora della loro diffusione. Essi devono essere stati infatti introdotti dall'uomo, per ragioni diverse, fino dalle epoche preistoriche e/o protostoriche.
(S)erban PROCHE(S); Syd RAMDHANI
The relationships of Madagascan plant and animal taxa have been the object of much fascination,Madagascar sharing numerous lineages with Africa,others with Asia,Australia,or the Americas,and many others being of uncertain relationships.In commonly accepted global regionalization schemata,Madagascar is treated together with Africa for animals,and with Africa,tropical Asia and the Pacific islands in the case of plants.Here we examine the similarities between the biotic assemblages of (ⅰ)tropical Africa,(ⅱ) Madagascar,and (ⅲ) the rest of the world,on a basic taxonomic level,considering the families of vascular plants and vertebrates as analysis units.The percentages of endemic families,families shared pair-wise between regions,or present in all three,are roughly similar between the two broad groups,though plant famlies with ranges limited to one region are proportionally fewer.In dendrograms and multidimensional scaling plots for different groups,Madagascar clusters together with Africa,Asia or both,and sometimes with smaller Indian Ocean Islands,but quite often (though not in plants) as a convincingly separate cluster.Our results for vertebrates justify the status of full zoogeographic region for Madagascar,though an equally high rank in geobotanical regionaliration would mean also treating Africa and Tropical Asia as separate units,which would be debatable given the overall greater uniformity of plant assemblages.Beyond the Madagascan focus of this paper,the differences between plant and vertebrate clusters shown here suggest different levels of ecological plasticity at the same taxonomic level,with plant families being much more environmentally-bound,and thus clustering along biome lines rather than regional lines.
Kooistra, Wiebe H C F; Sarno, Diana; Balzano, Sergio; Gu, Haifeng; Andersen, Robert A; Zingone, Adriana
Recent studies have shown that the cosmopolitan diatom Skeletonema costatum sensu lato is composed of several morphologically and genetically distinct species. To assess whether the separate species have a cosmopolitan distribution, we analysed 184 strains from marine and estuarine sites worldwide. We identified the strains using light and electron microscopy, and we sequenced the hyper-variable region of nuclear LSU rDNA. All recently described species were genetically distinct, and all but two were morphologically distinct. Variability was found for the only ultrastructural character used to distinguish Skeletonema dohrnii and S. marinoi, which cannot be identified based on morphology alone. Furthermore, multiple genetically distinct taxa, which may represent cryptic species, were found within the S. menzelii and S. tropicum clades. We found that all currently recognized species of Skeletonema are widespread, however, gaps seem to occur in their geographical ranges. For example, some species are found in both the northern and southern temperate latitudes whereas other species appear to have only subtropical to tropical ranges. Skeletonema pseudocostatum and S. grethae seem to have more restricted geographical ranges because the former was not found along American coasts and the latter was encountered only in US waters. A taxonomic update is provided for Skeletonema strains currently available in several culture collections, which could aid reinterpretation of results obtained in comparative studies using these strains. PMID:18042429
Larson, Greger; Karlsson, Elinor K.; Perri, Angela;
geographic locations of 14 so-called "ancient" breeds (defined by their genetic differentiation) resulted in a counterintuitive pattern. First, none of the ancient breeds derive from regions where the oldest archeological remains have been found. Second, three of the ancient breeds (Basenjis, Dingoes, and...
Steffen, Simone; Ball, Peter; Mucina, Ladislav; Kadereit, Gudrun
Background and Aims Sarcocornia comprises about 28 species of perennial succulent halophytes distributed worldwide, mainly in saline environments of warm-temperate and subtropical regions. The genus is characterized by strongly reduced leaves and flowers, which cause taxonomic difficulties; however, species in the genus show high diversity in growth form, with a mat-forming habit found in coastal salt marshes of all continents. Sarcocornia forms a monophyletic lineage with Salicornia whose...
White, Brian N.
The first cladogram to treat oceanic water masses as distinct geographic units presents a ‘hydrotectonic’ history of Pacific surface water masses. It is used to test the idea that the oceanographic subdivision of the surface waters of the Pacific Basin into separate water masses shaped pelagic biogeographic patterns in much the same way that the tectonic fragmentation of Pangea influenced biogeographic patterns on land. The historical water-mass relationships depicted by the surface water-mass cladogram resemble modern pelagic biogeographic regions. The prediction that the cladistic phylogenies of monophyletic groups having allopatric taxa in three or more surface water masses will be consistent with the topology of the surface water-mass cladogram is met by the pelagic fish genera Stomias and Evermanella.
Olesen, Jens Mogens; Alarcón, M.; Ehlers, Bodil;
the species, and at least C. jacobaea had both insect- and self-pollination. Several morphological traits were interpreted as adaptations to bird and lizard pollination, e.g. all had a robust flower morphology and, in addition, bird-pollinated species were scentless, whereas lizard-pollinated species...... of these species and their relatives were gathered from atpB, matK, rbcL and trnL-F regions, building the most complete phylogeny of Campanulaceae to date. Six of the island bellflower species were bird-pollinated and two (A. vidalii and M. aurea) were lizard-pollinated. Insects also visited some of...
water body to another involves dangerous changes of the environment, and the ability to avoid desiccation during transport is crucial. So, air-borne and ectozoic dispersal by birds or mammals can only work at short distances. This danger may be avoided by endozoic dispersal of thick-walled cysts; as far......—show distribution types comparable to those found in, e.g., blue–greens and desmids, whose cell construction appears much better adapted for dispersal....
A total of 98 liverwort species (43 genera, 10 families), 54 moss species (33 genera, 17 families) and one species of hornwort have been reported for Cocos Island (5°32’N, 87°04’W), Costa Rica. Over 60% of the bryophytes have a Neotropical or Pantropical distribution, about 10% are Caribbean, and less than 5% are endemic or subendemic. In comparison to the Galapagos Archipelago, Cocos Island harbors a more typical tropical bryoflora with foliose hepatics (e. g. Lejeuneaceae, Lepidoziaceae) co...
Full Text Available Increasing food production without compromising biodiversity is one of the great challenges for humanity. The aims of my thesis were to define spatial priorities for biodiversity conservation and to evaluate conservation conflicts considering agricultural expansion in the 21st century. I also tested the effect of globalizing conservation efforts on both food production and biodiversity conservation. I found spatial conflicts between biodiversity conservation and agricultural expansion. However, incorporating agricultural expansion data into the spatial prioritization process can significantly alleviate conservation conflicts, by reducing spatial correlation between the areas under high impact of agriculture and the priority areas for conservation. Moreover, developing conservation blueprints at the global scale, instead of the usual approach based on national boundaries, can benefit both food production and biodiversity. Based on these findings I conclude that the incorporation of agricultural expansion as a key component for defining global conservation strategies should be added to the list of solutions for our cultivated planet.
Archer, Will; Pop, Cornel M; Gunz, Philipp; McPherron, Shannon P
'Still Bay' is the name given to a cultural phase within the southern African Middle Stone Age, which remains critical to our understanding of modern human behavioural evolution. Although represented in only a handful of sites, the Still Bay is widespread geographically and, at certain localities, persisted over a substantial period of time. Many studies have focused on tracing the temporal range and geographic reach of the Still Bay, as well as inferring degrees of early modern human demographic connectedness from these parameters. Variation within the Still Bay, relative to the accuracy with which it can be identified, has received considerably less attention. However, demographic models based on the spread of the Still Bay in space and time hinge on the reliability with which it can be recognized in the archaeological record. Here we document patterns of bifacial point shape and size variation in some key Still Bay assemblages, and analyse these patterns using the statistical shape analysis tools of geometric morphometrics. Morphological variation appears to be geographically structured and is driven by the spatial separation between north-eastern and south-western clusters of sites. We argue that allometric variation is labile and reflects environmentally driven differences in point reduction, whereas shape differences unrelated to size more closely reflect technological and cultural fragmentation. Our results suggest that the biogeographic structure of Middle Stone Age populations was complex during the period associated with the Still Bay, and provide little support for heightened levels of cultural interconnectedness between distantly separated groups at this time. We briefly discuss the implications of our findings for tracing classic techno-traditions in the Middle Stone Age record of southern Africa, and for inferring underpinning population dynamics from these patterns. PMID:27457545
Ratnam, Jayashree; Tomlinson, Kyle W; Rasquinha, Dina N; Sankaran, Mahesh
The savannahs of Asia remain locally unrecognized as distinctive ecosystems, and continue to be viewed as degraded forests or seasonally dry tropical forests. These colonial-era legacies are problematic, because they fail to recognize the unique diversity of Asian savannahs and the critical roles of fire and herbivory in maintaining ecosystem health and diversity. In this review, we show that: the palaeo-historical evidence suggests that the savannahs of Asia have existed for at least 1 million years, long before widespread landscape modification by humans; savannah regions across Asia have levels of C4 grass endemism and diversity that are consistent with area-based expectations for non-Asian savannahs; there are at least three distinct Asian savannah communities, namely deciduous broadleaf savannahs, deciduous fine-leafed and spiny savannahs and evergreen pine savannahs, with distinct functional ecologies consistent with fire- and herbivory-driven community assembly. Via an analysis of savannah climate domains on other continents, we map the potential extent of savannahs across Asia. We find that the climates of African savannahs provide the closest analogues for those of Asian deciduous savannahs, but that Asian pine savannahs occur in climates different to any of the savannahs in the southern continents. Finally, we review major threats to the persistence of savannahs in Asia, including the mismanagement of fire and herbivory, alien woody encroachment, afforestation policies and future climate uncertainty associated with the changing Asian monsoon. Research agendas that target these issues are urgently needed to manage and conserve these ecosystems.This article is part of the themed issue 'Tropical grassy biomes: linking ecology, human use and conservation'. PMID:27502371
Streelman, J T; Alfaro, M; Westneat, M W; Bellwood, D R; Karl, S A
The family Scaridae comprises about 90 species of herbivorous coral reef, rock reef, and seagrass fishes. Parrotfishes are important agents of marine bioerosion who rework the substrate with their beaklike oral jaws. Many scarid populations are characterized by complex social systems including highly differentiated sexual stages, territoriality, and the defense of harems. Here, we test a hypothesis of relationships among parrotfish genera derived from nearly 2 kb of nuclear and mitochondrial DNA sequence. The DNA tree is different than a phylogeny based on comparative morphology and leads to important reinterpretations of scarid evolution. The molecular data suggest a split among seagrass and coral reef associated genera with nearly 80% of all species in the coral reef clade. Our phylogenetic results imply an East Tethyan origin of the family and the recurrent evolution of excavating and scraping feeding modes. It is likely that ecomorphological differences played a significant role in the initial divergence of major scarid lineages, but that variation in color and breeding behavior has triggered subsequent diversification. We present a two-phase model of parrotfish evolution to explain patterns of comparative diversity. Finally, we discuss the application of this model to other adaptively radiating clades. PMID:12093031
Linse, Katrin; Griffiths, Huw J.; Barnes, David K. A.; Clarke, Andrew
For many decades molluscan data have been critical to the establishment of the concept of a global-scale increase in species richness from the poles to the equator. Low polar diversity is key to this latitudinal cline in diversity. Here we investigate richness patterns in the two largest classes of molluscs at both local and regional scales throughout the Southern Ocean. We show that biodiversity is very patchy in the Southern Ocean (at the 1000-km scale) and test the validity of historical biogeographic sub-regions and provinces. We used multivariate analysis of biodiversity patterns at species, genus and family levels to define richness hotspots within the Southern Ocean and transition areas. This process identified the following distinct sub-regions in the Southern Ocean: Antarctic Peninsula, Weddell Sea, East Antarctic—Dronning Maud Land, East Antarctic—Enderby Land, East Antarctic—Wilkes Land, Ross Sea, and the independent Scotia arc and sub Antarctic islands. Patterns of endemism were very different between the bivalves and gastropods. On the basis of distributional ranges and radiation centres of evolutionarily successful families and genera we define three biogeographic provinces in the Southern Ocean: (1) the continental high Antarctic province excluding the Antarctic Peninsula, (2) the Scotia Sea province including the Antarctic Peninsula, and (3) the sub Antarctic province comprising the islands in the vicinity of the Antarctic Circumpolar Current.
Harper, David A T; Rasmussen, Christian M Ø; Liljeroth, Maria;
local biodiversity epicentres, notably on the South China Palaeoplate; low-latitude porambonitoid-dominated faunas with early plectambonitoid and clitambonitoid representatives, as well as high-latitude assemblages mostly dominated by orthoids, can be recognized, but many taxa are rooted in Late....... Biodiversity epicentres were located on most of the larger palaeoplates, as well as within the Iapetus Ocean. Provincial patterns were disrupted during the Sandbian and early Katian with the migration of many elements of the benthos into deeper-water regimes, enjoying a more cosmopolitan distribution. Later...
Background/Question/Methods: The national U.S.D.A. Conservation Effects Assessment Project (CEAP) is a multi-agency effort to quantify the environmental benefits of conservation practices. The goal of CEAP is to determine the effectiveness of wetland conservation practices and programs, including im...
Full Text Available We provide a list of the 392 described species of Staphylinidae confined to coastal habitats worldwide. The list is in taxonomic sequence by subfamily, tribe, and genus and includes 91 genera. We provide the page reference of the original description of every species and genus listed and of many synonyms. We note the existence of recent reviews, phylogenies and keys of each of the tribes and genera included. Coastal Staphylinidae contain eight subfamilies: Microsilphinae, Omaliinae, Pselaphinae, Aleocharinae, Oxytelinae, Scydmaeninae, Paederinae, and Staphylininae. By ‘coastal habitats’ we mean habitats existing on the sea coast and subject to inundation or at least splashing by the very highest tides. This includes rocky, boulder, coral, sandy, and muddy seashores, and at least portions of salt-marshes, estuaries, and mangrove swamps. We exclude the sand dune habitat and higher parts of sea-cliffs. The list notes distribution of all the species, first according to the ocean or sea on whose shores it has been recorded, and second by country (and for the larger countries by province or state. Although this distribution is undoubtedly incomplete, it provides a basis for future development of a dedicated database. The ‘Habitats, Habits, and Classificatory Notes’ section is designed to provide ecologists with further taxonomic and ecological information. It includes references to descriptions of the immature stages, behavior of adults and immatures, their food, natural enemies, and habitat. We would have preferred to separate these entities, but current knowledge of ecology is developed in few instances beyond natural history. The Pacific Ocean basin was the origin and contributed to the dispersal of the majority of specialist coastal Staphylinidae at the level of genus. However, at the level of species, species belonging to non-coastal-specialist genera are about as likely to occur on the shores of other oceans as on the shores of the Pacific. This difference is a reflection of the antiquity of coastal genera and species. A complete bibliography, and habitat and habitus photographs of some representative coastal Staphylinidae species are provided.
Castillon, David A.
This unit is designed to help social studies or science teachers incorporate ecological concepts into the teaching of science and Missouri geography. The unit includes: (1) a topic outline; (2) general unit objectives; (3) an introduction to basic biogeographical concepts; (4) descriptions of the glaciated prairie, unglaciated prairie, ozark, and…
J.P.;; Thomson, J. A.; Stratford, J. K.; Paul G Wolf
Bracken ferns (genus Pteridium) represent an ancient species complex with a natural worldwide distribution. Pteridium has historically been treated as comprising a single species, but recent treatments have recognized several related species. Phenotypic plasticity, geographically structured morphological variation, and geographically biased sampling have all contributed to taxonomic confusion in the genus. We sampled bracken specimens worldwide and used variable regions of the chloroplast gen...
Jønsson Knud A
Full Text Available Abstract Background Crows and ravens (Passeriformes: Corvus are large-brained birds with enhanced cognitive abilities relative to other birds. They are among the few non-hominid organisms on Earth to be considered intelligent and well-known examples exist of several crow species having evolved innovative strategies and even use of tools in their search for food. The 40 Corvus species have also been successful dispersers and are distributed on most continents and in remote archipelagos. Results This study presents the first molecular phylogeny including all species and a number of subspecies within the genus Corvus. We date the phylogeny and determine ancestral areas to investigate historical biogeographical patterns of the crows. Additionally, we use data on brain size and a large database on innovative behaviour and tool use to test whether brain size (i explains innovative behaviour and success in applying tools when foraging and (ii has some correlative role in the success of colonization of islands. Our results demonstrate that crows originated in the Palaearctic in the Miocene from where they dispersed to North America and the Caribbean, Africa and Australasia. We find that relative brain size alone does not explain tool use, innovative feeding strategies and dispersal success within crows. Conclusions Our study supports monophyly of the genus Corvus and further demonstrates the direction and timing of colonization from the area of origin in the Palaearctic to other continents and archipelagos. The Caribbean was probably colonized from North America, although some North American ancestor may have gone extinct, and the Pacific was colonized multiple times from Asia and Australia. We did not find a correlation between relative brain size, tool use, innovative feeding strategies and dispersal success. Hence, we propose that all crows and ravens have relatively large brains compared to other birds and thus the potential to be innovative if conditions and circumstances are right.
Lynch, Heather L.; Grant, Evan H. Campbell; Muneepeerakul, Rachata; Arunachalam, Muthukumarasamy; Rodriguez-Iturbe, Ignacio; Fagan, William F.
Interbasin water transfer projects, in which river connectivity is restructured via man-made canals, are an increasingly popular solution to address the spatial mismatch between supply and demand of fresh water. However, the ecological consequences of such restructuring remain largely unexplored, and there are no general theoretical guidelines from which to derive these expectations. River systems provide excellent opportunities to explore how network connectivity shapes habitat occupancy, community dynamics, and biogeographic patterns. We apply a neutral model (which assumes competitive equivalence among species within a stochastic framework) to an empirically derived river network to explore how proposed changes in network connectivity may impact patterns of freshwater fish biodiversity. Without predicting the responses of individual extant species, we find the addition of canals connecting hydrologically isolated river basins facilitates the spread of common species and increases average local species richness without changing the total species richness of the system. These impacts are sensitive to the parameters controlling the spatial scale of fish dispersal, with increased dispersal affording more opportunities for biotic restructuring at the community and landscape scales. Connections between isolated basins have a much larger effect on local species richness than those connecting reaches within a river basin, even when those within-basin reaches are far apart. As a result, interbasin canal projects have the potential for long-term impacts to continental-scale riverine communities.
Cortés-Ortiz, L; Bermingham, E; Rico, C; Rodríguez-Luna, E; Sampaio, I; Ruiz-García, M
We take advantage of the broad distribution of howler monkeys from Mexico to Argentina to provide a historical biogeographical analysis on a regional scale that encompasses the entire Neotropics. The phylogenetic relationships among 9 of the 10 recognized Alouatta species were inferred using three mitochondrial and two nuclear genes. The nuclear gene regions provided no phylogenetic resolution among howler monkey species, and were characterized by very low levels of sequence divergence between Alouatta and the Ateles outgroup. The mtDNA genes, on the other hand, produced a well-resolved phylogeny, which indicated that the earliest split among howler monkeys separated cis- and trans-Andean clades. Eight monophyletic mtDNA haplotype clades were identified, representing six named species in South America, including Alouatta seniculus, Alouatta sara, Alouatta macconelli, Alouatta caraya, Alouatta belzebul, and Alouatta guariba, and two in Mesoamerica, Alouatta pigra and Alouatta palliata. Molecular clock-based estimates of branching times indicated that contemporary howler monkey species originated in the late Miocene and Pliocene, not the Pleistocene. The causes of Alouatta diversification were more difficult to pin down, although we posit that the initial cis-, trans-Andean split in the genus was caused by the late Miocene completion of the northern Andes. Riverine barriers to dispersal and putative forest refuges can neither be discounted nor distinguished as causes of speciation in many cases, and one, the other or both have likely played a role in the diversification of South American howler monkeys. Finally, we estimated the separation of Mesoamerican A. pigra and A. palliata at 3Ma, which corresponds to the completion date of the Panama Isthmus promoting a role for this earth history event in the speciation of Central American howler monkeys. PMID:12470939
Cardinal-McTeague, Warren M; Sytsma, Kenneth J; Hall, Jocelyn C
Brassicales is a diverse order perhaps most famous because it houses Brassicaceae and, its premier member, Arabidopsis thaliana. This widely distributed and species-rich lineage has been overlooked as a promising system to investigate patterns of disjunct distributions and diversification rates. We analyzed plastid and mitochondrial sequence data from five gene regions (>8000bp) across 151 taxa to: (1) produce a chronogram for major lineages in Brassicales, including Brassicaceae and Arabidopsis, based on greater taxon sampling across the order and previously overlooked fossil evidence, (2) examine biogeographical ancestral range estimations and disjunct distributions in BioGeoBEARS, and (3) determine where shifts in species diversification occur using BAMM. The evolution and radiation of the Brassicales began 103Mya and was linked to a series of inter-continental vicariant, long-distance dispersal, and land bridge migration events. North America appears to be a significant area for early stem lineages in the order. Shifts to Australia then African are evident at nodes near the core Brassicales, which diverged 68.5Mya (HPD=75.6-62.0). This estimated age combined with fossil evidence, indicates that some New World clades embedded amongst Old World relatives (e.g., New World capparoids) are the result of different long distance dispersal events, whereas others may be best explained by land bridge migration (e.g., Forchhammeria). Based on these analyses, the Brassicaceae crown group diverged in Europe/Northern Africa in the Eocene, circa 43.4Mya (HPD=46.6-40.3) and Arabidopsis separated from close congeners circa 10.4Mya. These ages fall between divergent dates that were previously published, suggesting we are slowly converging on a robust age estimate for the family. Three significant shifts in species diversification are observed in the order: (1) 58Mya at the crown of Capparaceae, Cleomaceae and Brassicaceae, (2) 38Mya at the crown of Resedaceae+Stixis clade, and (3) 21Mya at the crown of the tribes Brassiceae and Sisymbrieae within Brassicaceae. PMID:26993763
Ma, Ka Yan; Craig, Matthew Thomas; Choat, John Howard; van Herwerden, Lynne
Groupers (family Epinephelidae) are a clade of species-rich, biologically diverse reef fishes. Given their ecological variability and widespread distribution across ocean basins, it is important to scrutinize their evolutionary history that underlies present day distributions. This study investigated the patterns and processes by which grouper biodiversity has been generated and what factors have influenced their present day distributions. We reconstructed a robust, time-calibrated molecular phylogeny of Epinephelidae with comprehensive (∼87%) species sampling, whereby diversification rates were estimated and ancestral ranges were reconstructed. Our results indicate that groupers originated in what is now the East Atlantic during the mid-Eocene and diverged successively to form six strongly supported main clades. These clades differ in age (late Oligocene to mid-Miocene), geographic origin (West Atlantic to West Indo-Pacific) and temporal-spatial diversification pattern, ranging from constant rates of diversification to episodes of rapid radiation. Overall, divergence within certain biogeographic regions was most prevalent in groupers, while vicariant divergences were more common in Tropical Atlantic and East Pacific groupers. Our findings reveal that both biological and geographical factors have driven grouper diversification. They also underscore the importance of scrutinizing group-specific patterns to better understand reef fish evolution. PMID:26908372
Oliver, W.A., Jr.
Three marine benthic faunal realms can be recognized in the Early and Middle Devonian. The Eastern Americas Realm consisted of most of the eastern half of North America and South America north of the Amazon. This realm extended in a southwest direction from the Devonian equator to approximately 35??S and was an isolated epicontinental sea during much of its history. The Eastern Americas Realm was bounded on the west by the Transcontinental Arch, on the north by the Canadian Shield and on the east and southeast by a peninsular extension of the Old Red Continent. These barriers were emergent during much, but not all, of Devonian time. Seaways beyond these barriers belonged to the Old World Realm. The Malvinokaffric Realm that was farther south was apparently temperate to arctic in climate and latitudinal position and contained few corals. Rugose corals in the Eastern Americas Realm show increasing generic-level endemism from the Late Silurian through the Early Devonian; during the late Early Devonian, 92% of the rugosan genera are not known anywhere else in the world. Endemism decreased through the Middle Devonian to zero in the early Late Devonian. The Early Devonian increase in endemism paralleled, and was probably related to, the development of the Old Red Continent as a barrier between America and Africa-Europe. The waning of endemism in the Middle Devonian reflects the breaching of the land barriers. This permitted some migration in and out of the realm in early Middle Devonian time but greatest movements were in late Middle Devonian time. Principal migration directions were from western or Arctic North America into the Michigan-Hudson Bay area and from the southern Appalachian area into Africa. ?? 1977.
Santini, Francesco; Sorenson, Laurie; Alfaro, Michael E
Bodianus wrasses comprise one of the most diverse genera of labrids. Also known as hogfishes due to the presence of a large pig-like snout, Bodianus species are found in warm waters across the Pacific, Atlantic and Indian Oceans. To this date no densely sampled molecular phylogeny is available for this group, and a single morphological study did not include two genera (Clepticus and Semicossyphus) that have been shown to belong within hogfishes by molecular studies. Our study produced the first multi-locus molecular phylogeny of Bodianus species, and corroborated the non-monophyly of this group without the inclusion of the Creole wrasse (Clepticus) and the sheepheads (Semicossyphus). We further showed that hogfishes and allies started to radiate during the Early Miocene, ∼20Ma, and that while this group originated in the Indo-western and South-western Pacific, it experienced multiple episodes during which it successfully invaded different geographic regions and/or ocean basins. PMID:26944013
Strains of Pseudomonas fluorescens producing the antibiotic 2,4-diacetylphloroglucinol (phlD+) are biocontrol agents of soilborne pathogens and play a key role in the disease suppressiveness of some soils. Considerable variation among isolates has been observed by using genomic fingerprinting techn...
Aquatic invaders are a major threat to ecological integrity and biodiversity of marine, estuarine, and freshwater ecosystems around the world. These invaders have been successful in passing through four discrete phases in their invasion of a new environment: (1) transport, (2) ...
Llewellyn, Martin S; McGinnity, Philip; Dionne, Melanie; Letourneau, Justine; Thonier, Florian; Carvalho, Gary R; Creer, Simon; Derome, Nicolas
Although understood in many vertebrate systems, the natural diversity of host-associated microbiota has been little studied in teleosts. For migratory fishes, successful exploitation of multiple habitats may affect and be affected by the composition of the intestinal microbiome. We collected 96 Salmo salar from across the Atlantic encompassing both freshwater and marine phases. Dramatic differences between environmental and gut bacterial communities were observed. Furthermore, community composition was not significantly impacted by geography. Instead life-cycle stage strongly defined both the diversity and identity of microbial assemblages in the gut, with evidence for community destabilisation in migratory phases. Mycoplasmataceae phylotypes were abundantly recovered in all life-cycle stages. Patterns of Mycoplasmataceae phylotype recruitment to the intestinal microbial community among sites and life-cycle stages support a dual role for deterministic and stochastic processes in defining the composition of the S. salar gut microbiome. PMID:26517698
Fernández-Palacios, José María
An analysis of changes in island topography and climate that have occurred since the last glacial maximum 21,000 years ago shows how sea-level change has influenced the current biodiversity of oceanic islands. See Letter p.99
Briggs, J. C.
Geophysical maps depicting continental movement have consistently shown India, as it moved northward, to be located far out in the Tethys Sea. India split off from the African east coast about 148 m.y.a. From that time onward, according to almost all geophysical accounts, India was isolated from all of other continents until the early Miocene when it made contact with Eurasia. But the biological data, both fossil and Recent, indicate that this concept cannot be correct. If India had really existed as an isolated, oceanic continent for about 100 m.y., it should have developed a peculiar biota with many endemic genera and families in its terrestrial and shallow marine habitats. But there are virtually no remains of organisms indicating that India was isolated for any substantial time (millions of years). Instead, we find that almost all Indian taxa were possessed in common with other continents. As time went on, the northern relationships became stronger and the southern ones weaker. Most of the recent geophysical accounts show India not making contact with Eurasia until the early Miocene, but fossil materials show that this event must have taken place by the early Eocene. It has been postulated that, as India moved northward, it created a biogeographic barrier that separated marine fish populations and resulted in the east-west provinces that are now apparent in the Indian Ocean. At the same time, the barrier effect was supposed to have resulted in the formation of sister species that are now located far apart. Information currently available indicates that most living, tropical marine species are probably not over 3 m.y. old. Consequently, the northward movement of India, which took place primarily between 148 and 50 m.y.a., could have no bearing on the relationships of modern species.
Quantitative analyses of planktonic foraminiferal assemblages from Deep Sea Drilling Project (DSDP) Holes 334 and 410 demonstrate that subpolar and subtropical faunal provinces existed in the North Atlantic during the late Miocene. Climatic oscillations are clearly recorded in Hole 410 by variations in abundance of the Neogloboquadrina subpolar assemblage. These climatic oscillations have a period of about 1 m.y. Higher frequency oscillations with a periodicity of one to several hundred thousand years are evident from about 6.5 to 7.5 m.y. and are probably present throughout the entire late Miocene. A revised age of 7.0 m.y. is proposed for the first occurrence of the calcareous nannofossil Amaurolithus primus (the Amaurolithus datum). ?? 1981.
The eastern Asian and eastern North American disjunction in Juglans offers an opportunity to estimate the time since divergence of the Eurasian and American lineages and to compare it with paleobotanical evidences. Five chloroplast DNA non-coding spacer (NCS) sequences: trnT-trnF, psbA-trnH, atpB-r...
Vicencio Aguilar, M E; Fernández Alamo, M A
A list of the species and taxa of some pelagic animals from a tropical upwelling region, based on collections made off the coast of Costa Rica is presented. The list includes a total of 224 species, 53 genera and 11 subspecific forms in Cnidaria, Annelida, Mollusca, Artropoda (Crustacea), Chaetognatha and Pisces. PMID:9246370
Sérgio R. Posso; Reginaldo J. Donatelli
Cuckoos are widely distributed, but are concentrated in the tropics, where they occupy a wide range of habitats. Both terrestrial and arboreal behaviors can be found in this group, but there is no consensus on as to whether these behaviors have arisen more than once. Moreover, the historical distribution of cuckoos is poorly understood. This paper presents a biogeographyc analysis of the early history of the distribution of these birds. The analysis was performed by using the Principle of Par...
van der Lee, Theo; Zhang, Hao; van Diepeningen, Anne; Waalwijk, Cees
Differences in the geographic distribution of distinct trichothecene mycotoxins in wheat and barley were first recorded two decades ago. The different toxicological properties of deoxynivalenol (DON), nivalenol (NIV) and their acetylated derivatives require careful monitoring of the dynamics of these mycotoxins and their producers. The phylogenetic species concept has become a valuable tool to study the global occurrence of mycotoxin-producing Fusarium species. This has revolutionised our views on the terrestrial distribution of trichothecene-producing Fusaria in the context of agronomics, climatic conditions, and human interference by the global trade and exchange of agricultural commodities. This paper presents an overview of the dynamics of the different trichothecene-producing Fusarium species as well as their chemotypes and genotypes across different continents. Clearly not one global population exists, but separate ones can be distinguished, sometimes even sympatric in combination with different hosts. A population with more pathogenic strains and chemotypes can replace another. Several displacement events appear to find their origin in the inadvertent introduction of new genotypes into new regions: 3-acetyl-DON-producing F. graminearum in Canada; 3-acetyl-DON-producing F. asiaticum in Eastern China; 15-acetyl-DON F. graminearum in Uruguay; and NIV-producing F asiaticum in the southern United States. PMID:25530109
Duellman, William E; Marion, Angela B; Hedges, S Blair
A phylogenetic analysis of sequences from 503 species of hylid frogs and four outgroup taxa resulted in 16,128 aligned sites of 19 genes. The molecular data were subjected to a maximum likelihood analysis that resulted in a new phylogenetic tree of treefrogs. A conservative new classification based on the tree has (1) three families composing an unranked taxon, Arboranae, (2) nine subfamilies (five resurrected, one new), and (3) six resurrected generic names and five new generic names. Using the results of a maximum likelihood timetree, times of divergence were determined. For the most part these times of divergence correlated well with historical geologic events. The arboranan frogs originated in South America in the Late Mesozoic or Early Cenozoic. The family Pelodryadidae diverged from its South American relative, Phyllomedusidae, in the Eocene and invaded Australia via Antarctica. There were two dispersals from South America to North America in the Paleogene. One lineage was the ancestral stock of Acris and its relatives, whereas the other lineage, subfamily Hylinae, differentiated into a myriad of genera in Middle America. PMID:27394762
Jønsson, Knud Andreas; Fabre, Pierre-Henri Fréderic; Irestedt, Martin
BACKGROUND:Crows and ravens (Passeriformes: Corvus) are large-brained birds with enhanced cognitive abilities relative to other birds. They are among the few non-hominid organisms on Earth to be considered intelligent and well-known examples exist of several crow species having evolved innovative...... Corvus. We date the phylogeny and determine ancestral areas to investigate historical biogeographical patterns of the crows. Additionally, we use data on brain size and a large database on innovative behaviour and tool use to test whether brain size (i) explains innovative behaviour and success in...... alone does not explain tool use, innovative feeding strategies and dispersal success within crows.CONCLUSIONS:Our study supports monophyly of the genus Corvus and further demonstrates the direction and timing of colonization from the area of origin in the Palaearctic to other continents and archipelagos...
Cibois, Alice; Thibault, Jean-Claude; Bonillo, Céline; Filardi, Christopher E; Watling, Dick; Pasquet, Eric
We reconstruct the phylogeny of fruit doves (genus Ptilinopus) and allies with a dense sampling that includes almost all species, based on mitochondrial and nuclear sequence data. We evaluate the most likely biogeographic scenario for the evolution of this group that colonized many islands of the Pacific Ocean. We also investigate the evolution of one of the main plumage character of fruit doves (the color of the crown), and we propose several revisions of the group's systematics. All Ptilinopus taxa formed a monophyletic group that includes two morphologically distinct genera, Alectroenas and Drepanoptila, confirming a previous result found with less species and genes. The divergence time analysis suggests that the basal divergences within Ptilinopus dated to the Early Oligocene, and the biogeographic analysis indicates that fruit doves originated most probably from the proto New Guinea region. The earliest dispersals from the New Guinea region to Oceania occurred with the colonization of New Caledonia and Fiji. A large group of Polynesian species (Central and Eastern), as well as the three taxa found in Micronesia and four species from the Guinean-Moluccan region, form the "purpuratus" clade, the largest diversification of fruit doves within Oceania, which also has a New Guinean origin. However, the eastbound colonization of fruit doves was not associated with a significant increase of their diversification rate. Overall, the Melanesian region did not act as a cradle for fruit doves, in contrast to the New Guinea region which is found as the ancestral area for several nodes within the phylogeny. PMID:24012584
Diversity, dynamics and biogeography of Chilean benthic nearshore ecosystems: an overview and guidelines for conservation Diversidad, dinámica y biogeografía del ecosistema costero bentónico de Chile: revisión y bases para conservación marina
Full Text Available Despite Chile has been one of the pioneering countries in studies of human impact on marine communities, and despite the enormous economic and social significance that the marine environment has for the country, the development of marine conservation programs and the scientific basis for sustainability has not kept pace, with the exploitation rate of marine fisheries and the increasing use of the coast for other purposes. Although we think that the establishment of any conservation policies along the vast coastline of Chile must be based on a multitude of approaches and considerations, scientific, biological, and ecological principles should guide much of these efforts. In this paper, we attempt to present a general overview of the current knowledge about the ecology and biogeography of nearshore systems in Chile. Based on the most relevant existing information, our goals are to: 1 Identify major biogeographic and ecological features of nearshore ecosystems, and the obvious gaps in information, 2 identify the most harmful human activities impacting the structure and dynamics of these systems, and 3 suggest the possible use of indicators to assess the conservational status of different environments along the coast. This overview shows, on one side, the geographic areas of deficitary knowledge on nearshore environments that are critical for future marine conservation and management plans, and on the other, the availability of high quality information for other geographic areas along the coast. Regarding the taxonomy and large-scale patterns of species distribution, important gaps in information were detected, however no big changes in the total number of species are expected in the future. There are few large-scale patterns of species distribution are reported in the literature, and in this contribution, but more work needs to be done, particularly for some taxa, to identify areas of high species diversity as well as areas which possess unique
Recent years have shown a rise in mean global temperatures and a shift in the geographical distribution of ectothermic animals. For a cause and effect analysis the present paper discusses those physiological processes limiting thermal tolerance. The lower heat tolerance in metazoa compared to unicellular eukaryotes and bacteria suggests that a complex systemic rather than molecular process is limiting in metazoa.Whole animal aerobic scope appears as the first process limited at low and high t...
Lutz, Stefanie; Anesio, Alexandre M.; Raiswell, Rob; Edwards, Arwyn; Newton, Rob J.; Gill, Fiona; Benning, Liane G.
The Arctic is melting at an unprecedented rate and key drivers are changes in snow and ice albedo. Here we show that red snow, a common algal habitat blooming after the onset of melting, plays a crucial role in decreasing albedo. Our data reveal that red pigmented snow algae are cosmopolitan as well as independent of location-specific geochemical and mineralogical factors. The patterns for snow algal diversity, pigmentation and, consequently albedo, are ubiquitous across the Arctic and the reduction in albedo accelerates snow melt and increases the time and area of exposed bare ice. We estimated that the overall decrease in snow albedo by red pigmented snow algal blooms over the course of one melt season can be 13%. This will invariably result in higher melt rates. We argue that such a `bio-albedo' effect has to be considered in climate models.
Fournie, G.; Goodman, S J; CRUZ, M.; Cedeno, V.; Velez, A; Patino, L.; Millins, C.; Gibbons, L. M.; Fox, M T; Cunningham, A.A.
The Galápagos giant tortoise is an icon of the unique, endemic biodiversity of Galápagos, but little is known of its parasitic fauna. We assessed the diversity of parasitic nematode communities and their spatial distributions within four wild tortoise populations comprising three species across three Galápagos islands, and consider their implication for Galápagos tortoise conservation programmes. Coprological examinations revealed nematode eggs to be common, with more than 80% of tortoises in...
Smith, Joshua B; Lamanna, Matthew C
Recent paleogeographic scenarios postulate the isolation of continental Africa during the Late Cretaceous. The absence of abelisaurid theropods from Upper Cretaceous African strata was offered as support of hypothesized African isolation with the acknowledgement that the paucity of African abelisaurids may be mostly an issue of sampling. Here we report on a shed theropod tooth from the Upper Cretaceous (Maastrichtian, approximately 70 Ma) Duwi Formation of Egypt. The tooth was referred to the Malagasy abelisaurid "Megalosaurus" crenatissimus (=Majungasaurus crenatissimus) in 1921. A discriminant function analysis was run to test for morphological congruence between the Egyptian tooth and the dentitions of 24 theropod taxa. The analysis correctly classified 96.6% of the teeth in the sample and assigned the tooth to Majungasaurus. As current paleogeographic reconstructions posit Madagascar had attained its current position relative to Africa before the Late Cretaceous, it is unlikely that the Egyptian tooth actually pertains to Majungasaurus. Nevertheless, its classification as an abelisaurid supports its referral to the clade. This tooth thus constitutes defensible evidence of an abelisaurid from the post-Cenomanian Cretaceous of mainland Africa. Combined with recent discoveries of abelisaurids in Niger and Morocco, the result indicates that Abelisauridae was a diverse group in Africa during the Cretaceous, existing in multiple places for at least approximately 25 Ma and weakens support for hypotheses of an isolated Africa during the Late Cretaceous. PMID:16541232
National Oceanic and Atmospheric Administration, Department of Commerce — This dataset represents depth predictions from a bathymetric model developed for the New York offshore spatial planning area. The model also includes...
Junhua Hu; Yang Liu
It remains a challenge to identify the geographical patterns and underlying environmental associations of species with unique ecological niches and distinct behaviors. This in turn hinders our understanding of the ecology as well as effective conservation management of threatened species. The white-eared night heron (Gorsachius magnificus) is a non-migratory nocturnal bird species that has a patchy distribution in the mountainous forests of East Asia. It is currently categorized as "Endangere...
Usher, K M; Fromont, J; Sutton, D C; Toze, S
The distribution, host associations, and phylogenetic relationships of the unicellular cyanobacterial symbionts of selected marine sponges were investigated with direct 16s rDNA sequencing. The results indicate that the symbionts of the marine sponges Aplysina aerophoba, Ircinia variabilis, and Petrosia ficiformis from the Mediterranean, four Chondrilla species from Australia and the Mediterranean, and Haliclona sp. from Australia support a diversity of symbionts comprising at least four closely related species of Synechococcus. These include the symbionts presently described as Aphanocapsa feldmannii from P. ficiformis and Chondrilla nucula. A fifth symbiont from Cymbastela marshae in Australia is an undescribed symbiont of sponges, related to Oscillatoria rosea. One symbiont, Candidatus Synechococcus spongiarum, was found in diverse sponge genera in the Mediterranean Sea and the Indian, Pacific, and Southern oceans, whereas others were apparently more restricted in host association and distribution. These results are discussed in terms of the biodiversity and biogeographic distributions of cyanobacterial symbionts. PMID:15546037
Full Text Available Few studies have explored the role of Cenozoic tectonic evolution in shaping patterns and processes of extant animal distributions within East Asian margins. We select Hynobius salamanders (Amphibia: Hynobiidae as a model to examine biogeographical consequences of Cenozoic tectonic events within East Asian margins. First, we use GenBank molecular data to reconstruct phylogenetic interrelationships of Hynobius by bayesian and maximum likelihood analyses. Second, we estimate the divergence time using the bayesian relaxed clock approach and infer dispersal/vicariance histories under the 'dispersal-extinction-cladogenesis' model. Finally, we test whether evolutionary history and biogeographical processes of Hynobius should coincide with the predictions of two major hypotheses (the 'vicariance'/'out of southwestern Japan' hypothesis. The resulting phylogeny confirmed Hynobius as a monophyletic group, which could be divided into nine major clades associated with six geographical areas. Our results show that: (1 the most recent common ancestor of Hynobius was distributed in southwestern Japan and Hokkaido Island, (2 a sister taxon relationship between Hynobius retardatus and all remaining species was the results of a vicariance event between Hokkaido Island and southwestern Japan in the Middle Eocene, (3 ancestral Hynobius in southwestern Japan dispersed into the Taiwan Island, central China, 'Korean Peninsula and northeastern China' as well as northeastern Honshu during the Late Eocene-Late Miocene. Our findings suggest that Cenozoic tectonic evolution plays an important role in shaping disjunctive distributions of extant Hynobius within East Asian margins.
Stephen J. Ivanyisky III; Albert, James S.
The Sternarchellini (Gymnotiformes, Apteronotidae) is a clade of 10 electric fish species that inhabit deep river channels of the Amazon and Orinoco basins, attain moderate adult body sizes (15-50 cm TL), and have a predatory life style. Here we trace the evolutionary origin and diversification of Sternarchellini using standard phylogenetic and biogeographic procedures and a dataset of 70 morphological characters. The main results are: 1) the genus Sternarchellaincludes both species currently...
Studying parasites of the genus Trichinella provides scientists of today many advantages. This is a group of zoonotic nematodes that circulate freely among wildlife hosts with one in particular, Trichinella spiralis that is particularly well adapted to domestic swine. Indeed, recent reports suggest ...
C Barry Cox
Full Text Available The marsupial and placental mammals originated at a time when the pattern of geographical barriers (oceans, shallow seas and mountains was very different from that of today, and climates were warmer. The sequence of changes in these barriers, and their effects on the dispersal of the mammal families and on the faunas of mammals in the different continents, are reviewed. The mammal fauna of South America changed greatly in the Pliocene/Pleistocene, when the newly-complete Panama Isthmus allowed the North American fauna to enter the continent and replace most of the former South American mammal families. Marsupial, but not placental, mammals reached Australia via Antarctica before Australia became isolated, while rats and bats are the only placentals that dispersed naturally from Asia to Australia in the late Cenozoic. Little is known of the early history of the mammal fauna of India. A few mammal families reached Madagascar from Africa in the early Cenozoic over a chain of islands. Africa was isolated for much of the early Cenozoic, though some groups did succeed in entering from Europe. Before the climate cooled in the mid-Cenozoic, the mammal faunas of the Northern Hemisphere were much richer than those of today.
species differed in their oceanographic distributions, with E. spinifer dominating oligotrophic waters of the subtropical gyres and E. hyalinus more abundant along central water mass boundaries and in frontal zones and upwelling systems. This species-specific difference in the oceanographic habitat is an...
Blair, Christopher; Sánchez-Ramírez, Santiago
Rattlesnakes (Crotalus and Sistrurus) represent a radiation of approximately 42 species distributed throughout the New World from southern Canada to Argentina. Interest in this enigmatic group of snakes continues to accrue due, in part, to their ecomorphological diversity, contributions to global envenomations, and potential medicinal importance. Although the group has garnered substantial attention from systematists and evolutionary biologists for decades, little is still known regarding patterns of lineage diversification. In addition, few studies have statistically quantified broad-scale biogeographic patterns in rattlesnakes to ascertain how dispersal occurred throughout the New World, particularly among the different major biomes of the Americas. To examine diversification and biogeographic patterns in this group of snakes we assemble a multilocus data set consisting of over 6700bp encompassing three nuclear loci (NT-3, RAG-1, C-mos) and seven mitochondrial genes (12S, 16S, ATPase6, ATPase8, ND4, ND5, cytb). Fossil-calibrated phylogenetic and subsequent diversification rate analyses are implemented using maximum likelihood and Bayesian inference, to examine their evolutionary history and temporal dynamics of diversity. Based on ancestral area reconstructions we explore dispersal patterns throughout the New World. Cladogenesis occurred predominantly during the Miocene and Pliocene with only two divergences during the Pleistocene. Two different diversification rate models, advocating diversity-dependence, are strongly supported. These models indicate an early rapid radiation followed by a recent speciation rate decline. Biogeographic analyses suggest that the high elevation pine-oak forests of western Mexico served as a major speciation pump for the majority of lineages, with the desert biome of western North America colonized independently at least twice. All together, these results provide evidence for rapid diversification of rattlesnakes throughout the Mexican highlands during the Neogene, likely in response to continual orogenesis of Mexico's major mountain systems, followed by more recent dispersal into desert and tropical biomes. PMID:26802208
Wüster, Wolfgang; Peppin, Lindsay; Pook, Catharine E; Walker, Daniel E
Despite their medical interest, the phylogeny of the snake family Viperidae remains inadequately understood. Previous studies have generally focused either on the pitvipers (Crotalinae) or on the Old World vipers (Viperinae), but there has been no comprehensive molecular study of the Viperidae as a whole, leaving the affinities of key taxa unresolved. Here, we infer the phylogenetic relationships among the extant genera of the Viperidae from the sequences of four mitochondrial genes (cytochrome b, NADH subunit 4, 16S and 12S rRNA). The results confirm Azemiops as the sister group of the Crotalinae, whereas Causus is nested within the Viperinae, and thus not a basal viperid or viperine. Relationships among the major clades of Viperinae remain poorly resolved despite increased sequence information compared to previous studies. Bayesian molecular dating in conjunction with dispersal-vicariance analysis suggests an early Tertiary origin in Asia for the crown group Viperidae, and rejects suggestions of a relatively recent, early to mid-Tertiary origin of the Caenophidia. PMID:18804544
Dedeine, Franck; Dupont, Simon; Guyot, Sylvain; Matsuura, Kenji; Wang, Changlu; Habibpour, Behzad; Bagnères, Anne-Geneviève; Mantovani, Barbara; Luchetti, Andrea
Termites of the genus Reticulitermes are ecologically and economically important wood-feeding social insects that are widespread in the Holarctic region. Despite their importance, no study has yet attempted to reconstruct a global time-scaled phylogeny of Reticulitermes termites. In this study, we sequenced mitochondrial (2096bp) and nuclear (829bp) loci from 61 Reticulitermes specimens, collected across the genus' entire range, and one specimen of Coptotermes formosanus, which served as an outgroup. Bayesian and Maximum likelihood analyses conducted on the mitochondrial and nuclear sequences support the existence of four main lineages that span four global geographical regions: North America (NA lineage), western Europe (WE lineage), a region including eastern Europe and western Asia (EA+WA lineage), and eastern Asia (EA lineage). The mitochondrial data allowed us to clarify the phylogenetic relationships among these lineages. They were also used to infer a chronogram that was time scaled based on age estimates for termite fossils (including the oldest Reticulitermes fossils, which date back to the late Eocene-early Oligocene). Our results support the hypothesis that the extant Reticulitermes lineage first differentiated in North America. The first divergence event in the ancestral lineage of Reticulitermes occurred in the early Miocene and separated the Nearctic lineages (i.e., the NA lineages) from the Palearctic lineages (i.e., WE, EE+WA, and EA lineages). Our analyses revealed that the main lineages of Reticulitermes diversified because of vicariance and migration events, which were probably induced by major paleogeographic and paleoclimatic changes that occurred during the Cenozoic era. This is the first global and comprehensive phylogenetic study of Reticulitermes termites, and it provides a crucial foundation for studying the evolution of phenotypic and life-history traits in Reticulitermes. For instance, the phylogeny we obtained suggested that 'asexual queen succession', a unique reproductive system, independently evolved at least three times during the diversification of the genus. PMID:26541239
Kryštufek, B.; Baxter, R. M.; Haberl, W.; Zima, Jan; Bužan, E. V.
Roč. 89, č. 2 (2008), s. 325-335. ISSN 0022-2372 R&D Projects: GA MŠk LC06073 Institutional research plan: CEZ:AV0Z60930519 Keywords : chromosomes * cytochrome-b gene * Grammomys * morphology * systematics Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 1.737, year: 2008 http://www.asmjournals.org/archive/1545-1542/89/2/pdf/i1545-1542-89-2-325.pdf
Searles, R. B.
The northern boundary of the warm temperate region of the mid-Atlantic coast of the United States is set at Cape Hatteras; the southern boundary lies at Cape Canaveral. There is some spillover of cool temperate species south of Cape Hatteras into North Carolina and spillover of warm temperate species south of Cape Canaveral toward Palm Beach. Elements of the warm temperate flora also extend into the northern Gulf of Mexico, but precise limits to the flora cannot be drawn there. Thirty-one species are endemic to the warm temperate flora. The inshore waters of North Carolina include approximately equal numbers of species with northern and southern centres of distribution; the species of the offshore waters have predominantly southern affinities, but also include most of the endemic species. Seasonal changes in the shallow water flora of North Carolina reflect eurythermal cool temperate and tropical elements in winter and summer respectively and a year-round warm temperate element. These groupings have been verified by experimental studies in which light and temperature were varied. The deep water flora is a summer flora dominated by perennial species. The inshore, eurythermal cool temperate and tropical species have a variety of cryptic stages by which they persist throughout the year.
Leach, Katie; Montgomery, W. Ian; Reid, Neil
1. In addition to abiotic determinants, biotic factors, including competitive, interspecific interactions, limit species’ distributions. Environmental changes in human disturbance, land use and climate are predicted to have widespread impacts on interactions between species, especially in the order Lagomorpha due to the higher latitudes and more extreme environmental conditions they occupy. 2. We reviewed the published literature on interspecific interactions in the order Lagomorpha, and comp...
Methanotrophic bacteria perform a central function in our climate system representing the only biogenic sink for the greenhouse gas methane. In wetland rice fields, they function as bio-filters preventing methane produced in anoxic layers escaping into the atmosphere, attenuating the potential methane emission by up to 90%. Despite intensive studies in the past, molecular approaches have barely started to explore the full diversit...
Full Text Available The ultra-structure of the shell and the morphometric variability of soil inhabiting testate amoeba Lamtopyxis callistoma from Madagascar were studied by using light- and scanning electron microscopy. The biometrical characteristic of the species was made on the basis of 75 specimens measured. In addition to the diameter of the shell, six other shell characters were described biometrically for the first time. The analysis of the variation coefficients shows that the studied population of L. callistoma is comparatively homogeneous and almost all measured characters are weakly to moderate variable (CV less than 10%. Scanning electron microscopy (SEM studies on the shell ultra-morphology show that it has a smooth apertural surface with a thick layer of porous and fibrous organic cement and a rough dorsal surface composed of bigger and angular pieces of quartz. The shell wall has a thickness of about 5-6 µm and is composed of three layers. Unlike the previously accepted opinion that species is characterized by the presence of four teeth, this study shows that population of L. callistoma from Madagascar is comprised of both, specimens with four teeth and specimens with three teeth, in ratio of about 60% to 40%. Taking into account the restricted geographical distribution, large sizes and characteristic apertural morphology of L. callistoma it is assumed that this species, like some bryophilic ‘Nebelas’ with circumaustral distribution (e.g. Apodera vas, Alocodera cockayni, Certesella certesi, Certesella martiali, etc., can be used as an example that in free-living microbial eukaryotes ‘not everything is everywhere’.
Advances in habitat and climate modelling allow us to reduce uncertainties of climate change impacts on species distribution. We evaluated the impacts of future climate change on community structure, diversity, distribution and phenology of 14 copepod species in the North Atlantic. We developed and validated habitat models for key zooplankton species using continuous plankton recorder (CPR) survey data collected at mid latitudes of the North Atlantic. Generalized additive models (GAMs) were applied to relate the occurrence of species to environmental variables. Models were projected to future (2080–2099) environmental conditions using coupled hydroclimatix–biogeochemical models under the Intergovernmental Panel on Climate Change (IPCC) A1B climate scenario, and compared to present (2001–2020) conditions. Our projections indicated that the copepod community is expected to respond substantially to climate change: a mean poleward latitudinal shift of 8.7 km per decade for the overall community with an important species range variation (–15 to 18 km per decade); the species seasonal peak is expected to occur 12–13 d earlier for Calanus finmarchicus and C. hyperboreus; and important changes in community structure are also expected (high species turnover of 43–79% south of the Oceanic Polar Front). The impacts of the change expected by the end of the century under IPCC global warming scenarios on copepods highlight poleward shifts, earlier seasonal peak and changes in biodiversity spatial patterns that might lead to alterations of the future North Atlantic pelagic ecosystem. Our model and projections are supported by a temporal validation undertaken using the North Atlantic climate regime shift that occurred in the 1980s: the habitat model built in the cold period (1970–1986) has been validated in the warm period (1987–2004).
Meilland, Julie; Fabri-Ruiz, Salomé; Koubbi, Philippe; Monaco, Claire Lo; Cotte, Cédric; Hosie, Graham W.; Sanchez, Sophie; Howa, Hélène
Within the framework of the Scientific Committee on Antarctic Research (SCAR) Southern Ocean-Continuous Plankton Recorder (SO-CPR) Survey, the oceanic regions around Crozet and Kerguelen Islands were investigated in February-March 2013. Living planktonic Foraminifera (LPF) were collected in the upper mixed layer with a CPR along a 2160 nautical mile sea transect that crossed main hydrological fronts in the Indian sector of the Southern Ocean. In the SO-CPR database, mean total abundances of Foraminifera occurring during late austral summer are highly variable at an inter-annual scale, from 10 to 250 ind.m-3, representing 10-40% of the total zooplankton abundance, respectively. In the Southern Ocean, major inter-annual changes in zooplankton community structure were already reported. In this study, we describe the large scale distributional pattern of individual planktonic foraminiferal species living in near-surface waters of the Indian sector of the Southern Ocean, and we attempt to explain why major spatial variability in relative species abundances occurs during a late austral summer. In February-March 2013, LPF total abundances recorded between 42.86°S and 56.42°S ranged from 0 to a maximum of 258 ind.m-3. In the Open Ocean Zone, the LPF community was composed of four major species (Globigerinita uvula, Neogloboquadrina pachyderma, Neogloboquadrina incompta, Globigerina bulloides). Generally, LPF total abundances are supposed to mirror primary production induced by hydrological fronts or induced by topography near Crozet and Kerguelen Islands. However, during late austral summer 2013, high foraminiferal abundances in the upper mixed layer did not always match the pattern of near-surface primary production (high Chl-a concentration areas delineated from satellite imagery). Low LPF standing stocks in late austral summer in the Southern Ocean contrasted with the presence of high densities of heavily silicified diatoms. This suggests that the late bloom production is not a suitable resource for planktonic Foraminifera. Consequently, LPF regional distribution in the upper mixed layer cannot be directly reconstructed from Chl-a concentration maps derived from satellite imagery. Knowledge of phytoplankton community composition is needed to understand the impact of primary production on foraminiferal population dynamics. Our results also emphasize that the polar/subpolar foraminiferal assemblages are characterized by high abundances of G. uvula in the iron-enriched waters surrounding the French Sub-Antarctic Islands. This species might react either to coastal or late summer production in high latitudes.
Prior to the 1960s the biota of the western Indian Ocean inshore marine habitats received scant attention from taxonomists resulting in a poorly known flora and fauna. Fortunately, over the last 40 years there have been considerable developments in the study of marine biodiversity in this region, both from regional scientists and by those based at institutions in Europe and elsewhere. This paper reviews the current status of taxonomic knowledge of the marine biodiversity of the western Ind...
Full Text Available The highland sandstones of southeastern Venezuela, termed collectivelly Pantepui, are one of the most wonderful landscapes of the planet because their biogeographical conditions have concentred hot spots of high endemicity, importantly birds. Analysis of some theories about the origins of endemics Pantepui bird fauna, would invoke an “andean origin” via Llanos; nevertheless, such theories revealed serious discordances: a if the south american migrating land birds movements seem to have had a directional pattern northern-southern: how well can we to explain a “pantepuian colonization” western-eastern? b if, geologically, orogenesis of Guayana Shield is much more ancient to Andes, some “chance colonization” could have enterprised from a vice versa route: Pantepui-Andes. c if, ecologically and phytophysiographically, both the tropical and subtropical conditions of northern and northeastern venezuelan cordilleras are highly similar to guianan highlands than Andes ones (e.g., “messenerhebung” effect and formerly both formations was nearest, logically, I would suggest a new route through those cordilleras, to avoiding the enormous llanean hopping (1000 km and their antagonistic ecological features. On the grounds, it would allow to explain, partially: 1 Occurrence of guianian species, e.g., Nannopsittaca panychlora, relict on peninsula of Paria 2 That pantepuian species are nearest allied, numerically, with northern and eastern cordilleras species than such as andean ones. It seems likely that cordillerean route, ecologically more accesible only having two barriers, depresion of Unare and Pantano Oriental, on the one hand, and the conspicuous amount of paleoendemic elements, on the other hand, it allow me to infer that the Pantepui region resulted an important diversification center instead colonization center bird fauna in ancient times. Such assumption should empathize, partially, with the controvertible croizatian school, which have inquired since long ago with the mayrian viewpoints about pantepuian bird fauna origin. In light the everincreasing effects of new empirical and theorical findings, I argue contribution, consistence and current of the theories so far postulated, by using the latest scientific conceptual achievements. Nevertheless, my interpretations should be considered merely a working model based on a number of inferences to it may serve for testing the biogeographical pattern of several lineages of tepuian bird fauna.
Host switching and geographical dispersal of parasites are common phenomena, occurring on many temporal and spatial scales. Diversification involves both coevolution and colonization to explain complex host ¬ parasite associations. Across the expanse of earth history, the major radiations in parasit...
Lynn G Clark
Full Text Available The present paper analyses the distribution of bamboos in New World. For convenience, bamboos are divided into two broad groups, the woody bamboos and the herbaceous bamboos. These categories do not necessarily reflect phylogenetic relationships among bamboo groups. The Bambuseae includes all of the woody bamboos and is probably monophyletic, whereas the herbaceous bamboos are classified into eight tribes. In the New World (including underscribed taxa, 45-46 genera and approximately 515 species are represented; only two genera: Arundinaria and Streptogyna are not exclusively neotropical. The area of greatest endemism and diversity is the humid coastal forests of Bahia, Brazil. 22 genera have been found in this relatively small area, representing 48% of all New World genera. Five of the 22 genera are endemic to the Bahia coastal forests.O presente trabalho analisa a distribuição geográfica dos bambus do Novo Mundo. Por questões práticas, os bambus foram divididos em dois grupos: os bambus lenhosos e os herbáceos, essas categorias entretanto, nem sempre refletem relacionamentos filogenéticos, pois embora as Bambuseae incluam todos os bambus lenhosos, sendo portanto provavelmetne monofiléticos, os bambus herbáceos são classificados em oito tribos. No Novo Mundo, (incluindo os taxa ainda não descritos existem cerca de 45-46 gêneros e aproximadamente 515 espécies. Desses gêneros, apenas dois: Arundinaria e Streptogyna não são exclusivamente neotropicais. A área de maior endemismo e diversidade do grupo, está nas florestas costeiras da Bahia, Brasil. Nesta região são encontrados 22 gêneros, representando 48% de todos os gêneros neotropicais e desses, 5 são exclusivos desta região da Bahia.
Whittaker, Robert J.; Rigal, François; Paulo A V Borges; Cardoso, Pedro; Terzopoulou, Sofia; Casanoves, Fernando; Pla, Laura; Guilhaumon, François; Richard J Ladle; Triantis, Kostas A.
Analyses of species-diversity patterns of remote islands have been crucial to the development of biogeographic theory, yet little is known about corresponding patterns in functional traits on islands and how, for example, they may be affected by the introduction of exotic species. We collated trait data for spiders and beetles and used a functional diversity index (FRic) to test for nonrandomness in the contribution of endemic, other native (also combined as indigenous), and exotic species to...
Colin R. Trainor
Full Text Available The Wallacean island of Timor is of particular biological interest due to its relatively large size and transitional location between the Indo-Malayan and Australasian biogeographic realms. However, the origins and levels of endemism of its invertebrate fauna are poorly known. A recent study of Timorese ants revealed a diverse fauna with predominantly Indo-Malayan affinities, but species-level taxonomy was considered to be too poorly understood for an analysis of levels of endemism. The highly diverse Old World tropical genus Polyrhachis represents a notable exception, and here we analyse levels of endemism in the Polyrhachis fauna of Timor and surrounding islands. We supplement the species listed in the previous study with additional collections to record a total of 35 species of Polyrhachis from Timor and surrounding islands. Only 14 (40% of the 35 species could be named (P. constricta, P. costulata, P. gab, P. sokolova, P. hera, P. illaudata, P. rixosa, P. acantha chrysophanes, P. saevissima, P. bicolor, P. cryptoceroides, P. dives, P. longipes and P. olybria, and the large majority of the remaining species have not previously been collected. These are very likely to be endemic to Timor and surrounding islands, and point to remarkably high levels (>50% of endemism in the regional ant fauna.
Akito Y Kawahara
Full Text Available BACKGROUND: The 1400 species of hawkmoths (Lepidoptera: Sphingidae comprise one of most conspicuous and well-studied groups of insects, and provide model systems for diverse biological disciplines. However, a robust phylogenetic framework for the family is currently lacking. Morphology is unable to confidently determine relationships among most groups. As a major step toward understanding relationships of this model group, we have undertaken the first large-scale molecular phylogenetic analysis of hawkmoths representing all subfamilies, tribes and subtribes. METHODOLOGY/PRINCIPAL FINDINGS: The data set consisted of 131 sphingid species and 6793 bp of sequence from five protein-coding nuclear genes. Maximum likelihood and parsimony analyses provided strong support for more than two-thirds of all nodes, including strong signal for or against nearly all of the fifteen current subfamily, tribal and sub-tribal groupings. Monophyly was strongly supported for some of these, including Macroglossinae, Sphinginae, Acherontiini, Ambulycini, Philampelini, Choerocampina, and Hemarina. Other groupings proved para- or polyphyletic, and will need significant redefinition; these include Smerinthinae, Smerinthini, Sphingini, Sphingulini, Dilophonotini, Dilophonotina, Macroglossini, and Macroglossina. The basal divergence, strongly supported, is between Macroglossinae and Smerinthinae+Sphinginae. All genes contribute significantly to the signal from the combined data set, and there is little conflict between genes. Ancestral state reconstruction reveals multiple separate origins of New World and Old World radiations. CONCLUSIONS/SIGNIFICANCE: Our study provides the first comprehensive phylogeny of one of the most conspicuous and well-studied insects. The molecular phylogeny challenges current concepts of Sphingidae based on morphology, and provides a foundation for a new classification. While there are multiple independent origins of New World and Old World radiations, we conclude that broad-scale geographic distribution in hawkmoths is more phylogenetically conserved than previously postulated.
Stevens, Calvin H.; Poole, Forrest G.; Amaya-Martínez, Ricardo
Three sets of fusulinid faunas in Sonora, Mexico, discussed herein, record different depositional and paleotectonic settings along the southwestern margin of Laurentia (North America) during Pennsylvanian and Permian time. The settings include: offshelf continental rise and ocean basin (Rancho Nuevo Formation in the Sonora allochthon), shallow continental shelf (La Cueva Limestone), and foredeep basin on the continental shelf (Mina México Formation). Our data represent 41 fusulinid collections from 23 localities with each locality providing one to eight collections. Reworked fusulinids in the Middle and Upper Pennsylvanian part of the Rancho Nuevo Formation range in age from Desmoinesian into Virgilian (Moscovian-Gzhelian). Indigenous Permian fusulinids in the La Cueva Limestone range in age from middle or late Wolfcampian to middle Leonardian (late Sakmarian-late Artinskian), and reworked Permian fusulinids in the Mina México Formation range in age from early to middle Leonardian (middle-late Artinskian). Conodonts of Guadalupian age occur in some turbidites in the Mina México Formation, indicating the youngest foredeep deposit is at least Middle Permian in age. Our fusulinid collections indicate a hiatus of at least 10 m.y. between the youngest Pennsylvanian (Virgilian) rocks in the Sonora allochthon and the oldest Permian (middle Wolfcampian) rocks in the region. Most fusulinid faunas in Sonora show affinities to those of West Texas, New Mexico, and Arizona; however, some genera and species are similar to those in southeastern California. As most species are similar to those east of the southwest-trending Transcontinental arch in New Mexico and Arizona, this arch may have formed a barrier preventing large-scale migration and mixing of faunas between the southern shelf of Laurentia in northwestern Mexico and the western shelf in the southwestern United States. The Sonora allochthon, consisting of pre-Permian (Lower Ordovician to Upper Pennsylvanian) deep-water continental-rise and ocean-basin rocks, was thrust northward 50–200 km over Permian and older shallow-water carbonate-shelf rocks and Permian deep-water foredeep rocks of southern Laurentia. As Triassic rocks unconformably overlie the Sonora allochthon, we conclude that terminal movement of the allochthon was in Late Permian time.
Sommer Ralf J
Full Text Available Abstract Background The nematode Pristionchus pacificus has originally been developed as a satellite organism for comparison to Caenorhabditis elegans. A 10X coverage of the whole genome of P. pacificus is available, making P. pacificus the first non-Caenorhabditis nematode with a fully sequenced genome. The macroevolutionary comparison between P. pacificus and C. elegans has been complemented by microevolutionary studies of closely related strains and species within the genus Pristionchus. In addition, new understanding of the biology of Pristionchus from field studies, demonstrating a close association with various scarab beetles and the Colorado potato beetle, supports consideration of this nematode in studies of ecosystems. In the course of field studies on four continents more than 1,200 isolates were established from 15,000 beetle specimens representing 18 Pristionchus species. Two remarkable features of the Pristionchus – beetle association are the high species specificity of the interaction and the interception of the beetle's sex communication system for host recognition by the nematodes, as suggested by chemotaxis studies. Evolutionary interpretations of differences in developmental, behavioral and ecological patterns require a phylogenetic framework of the genus Pristionchus. Results Here, we provide a robust phylogeny of all 18 available Pristionchus species based on a set of 27 ribosomal protein genes encompassing a total of 10,971 bp. The phylogenetic tree provides evidence for North American and European clades, which are embedded in a deeper clade that includes Asian species. It also indicates putative invasion events. Of the 18 Pristionchus species, 13 are gonochoristic and five are hermaphroditic. The phylogeny indicates that all hermaphroditic species have arisen independently within the genus Pristionchus. Conclusion Combined ribosomal protein cDNA data can provide the basis for reconstruction of a robust phylogenetic framework for microevolutionary and biogeographic analyses. An additional major implication of our studies is the use of Pristionchus for nematode biodiversity assessments. While some species are represented by more than 100 isolates, others were found less than four times. Such patterns were observed on all continents and in all phylogenetic clades indicating that species asymmetry is a widespread phenomenon, which can now be further investigated by molecular tools.
Gudynas, E.; Williams, J. D.; Mercedes Azpelicueta, de las, M.
This study of Chthonerpeton indistinctum (Reinhardt & Lütken, 1861) considers 25 morphometric characters, teeth-counts and sex, based on 96 specimens. A multivariate analysis of characters and comparisons of geographically arranged samples is carried out by graphic and statistical methods. No trends in geographical variation were found. Subsequently a redescription of the species is presented, including measurements and counts. Sexual dimorphism was observed for four characters related to the...
Eiserhardt, Wolf L.
evolutionary processes. These topics fall into four categories: (i) Previous empirical evidence on the factors influencing palm species distributions, community composition, and species richness was summarised in a hierarchical scale framework. The effects of different components of the abiotic environment....... Richnessenvironment relationships were found to be spatially variable; richness-water correlations decreased in strength, and richness-energy correlations increased in strength with latitude, indicating complex and systematic interactions between factors. Evolutionary history has a significant impact on continental...
Marivaux, Laurent; Antoine, Pierre-Olivier; Baqri, Syed Rafiqul Hassan; Benammi, Mouloud; Chaimanee, Yaowalak; Crochet, Jean-Yves; de Franceschi, Dario; Iqbal, Nayyer; Jaeger, Jean-Jacques; Métais, Grégoire; Roohi, Ghazala; Welcomme, Jean-Loup
Asian tarsiid and sivaladapid primates maintained relictual distributions in southern Asia long after the extirpation of their close Holarctic relatives near the Eocene–Oligocene boundary. We report here the discovery of amphipithecid and eosimiid primates from Oligocene coastal deposits in Pakistan that demonstrate that stem anthropoids also survived in southern Asia beyond the climatic deterioration that characterized the Eocene–Oligocene transition. These fossils provide data on temporal and paleobiogeographic aspects of early anthropoid evolution and significantly expand the record of stem anthropoid evolution in the Paleogene of South Asia. PMID:15937103
Marivaux, Laurent; Antoine, Pierre-Olivier; Baqri, Syed Rafiqul Hassan; Benammi, Mouloud; Chaimanee, Yaowalak; Crochet, Jean-Yves; De Franceschi, Dario; Iqbal, Nayyer; Jaeger, Jean-Jacques; Métais, Grégoire; Roohi, Ghazala; Welcomme, Jean-Loup
Asian tarsiid and sivaladapid primates maintained relictual distributions in southern Asia long after the extirpation of their close Holarctic relatives near the Eocene–Oligocene boundary. We report here the discovery of amphipithecid and eosimiid primates from Oligocene coastal deposits in Pakistan that demonstrate that stem anthropoids also survived in southern Asia beyond the climatic deterioration that characterized the Eocene–Oligocene transition. These fossils provide data on temporal a...
Full Text Available A legtöbb mérsékelt övi madárfaj életciklusában alapvető szerepet tölt be a vonulás. A rendszeres, nagy kiterjedésű mozgások, melyek a mérsékelt övi vonulási rendszereket jellemzik, egyes feltételezések szerint a trópusi fajok poszt-glaciális, északi irányú terjeszkedésével párhuzamosan jelentek meg. Ezen felül a vonulás előfordulását számos ökológiai tényező is befolyásolhatja, mint például a környezet szezonalitásának mértéke vagy a téli túlélést befolyásoló tényezők. A vonulás eredete és evolúciója ezért csak úgy érthető meg, ha a madarak biogeográfiai történetiségét és ökológiáját filogenetikai kontextusban tanulmányozzuk. Jelen vizsgálatban a vágómadár-alakúak (Accipitriformes vonulásának evolúcióját elemeztük komparatív módszerekkel. Első lépésben létrehoztunk egy fosszilis adatok alapján datált molekuláris törzsfát, amelyen jellegrekonstrukciót végeztünk és rekonstruáltuk a fajok ősi elterjedési területét. Az elemzéseink alapján a vonulás többször alakult ki a ragadozók esetében, legkorábban a héjaformákon (Accipitrinae belül, vélhetően a Miocén közepén. A legtöbb esetben a vonuló leszármazási vonalak nem vonuló őseinél trópusi elterjedésre következtethetünk. A direkcionális evolúciós teszt alapján a vonulás a trópusokon jelent meg és megnövelte a mérsékelt égöv kolonizációjának rátáját. Eszerint tehát a mérsékelt övi ragadozómadár fajok vonuló trópusi fajok leszármazottainak tekinthetők, melyek az erősen szezonális, északi élőhelyek irányába terjeszkedtek. Végezetül negatív kapcsolatot találtunk a vonulás megjelenése és a táplálékspecializáció mértéke között.
Ritchie, H.; Jamieson, A. J.; Piertney, S. B.
Amphipods of the superfamily Lysianassoidea are ubiquitous at hadal depths (>6000 m) and therefore are an ideal model group for investigating levels of endemism and the drivers of speciation in deep ocean trenches. The taxonomic classification of hadal amphipods is typically based on conventional morphological traits but it has been suggested that convergent evolution, phenotypic plasticity, intra-specific variability and ontogenetic variation may obscure the ability to robustly diagnose taxa and define species. Here we use phylogenetic analysis of DNA sequence variation at two mitochondrial (COI and 16S rDNA) and one nuclear (18S rDNA) regions at to examine the evolutionary relationships among 25 putative amphipod species representing 14 genera and 11 families that were sampled from across seven hadal trenches. We identify several instances where species, genera and families do not resolve monophyletic clades, highlighting incongruence between the current taxonomic classification and the molecular phylogeny for this group. Our data also help extend and resolve the known biogeographic distributions for the different species, such as identifying the co-occurrence of Hirondellea dubia and Hirondellea gigas in the Mariana trench.
Hibbs Jr., Douglas A.; Olsson, Ola
The most important event in human economic history before the Industrial Revolution was the Neolithic transition from a nomadic hunter-gatherer lifestyle to sedentary agriculture, beginning about 10,000 years ago. The transition made possible the human population explosion, the rise of non-foodproducing specialists, and the acceleration of technological progress that led eventually to the Industrial Revolution. But the transitio n occurred at different times in different regions of the world,...
Hastie, L. C.; Pierce, G.J.; Jing WANG; Bruno, I. (Isabel); Moreno, A.; Piatkowski, Uwe; Robin, J P
Cephalopods play a significant role in coastal and oceanic ecosystems, both as consumers of invertebrates and small fish and as the prey of some fish, seabirds and marine mammals and other large predators. Approximately 30 species of cephalopod have been recorded in the north-eastern Atlantic and adjacent waters, including 18 teuthid (squid), seven sepiolid (bobtail), three sepiid (cuttlefish) and 10 octopod (octopus) species. A number of these are exploited commercially and support important...
Crump, Byron C; Hopkinson, Charles S; Sogin, Mitchell L; Hobbie, John E
Shifts in bacterioplankton community composition along the salinity gradient of the Parker River estuary and Plum Island Sound, in northeastern Massachusetts, were related to residence time and bacterial community doubling time in spring, summer, and fall seasons. Bacterial community composition was characterized with denaturing gradient gel electrophoresis (DGGE) of PCR-amplified 16S ribosomal DNA. Average community doubling time was calculated from bacterial production ([(14)C]leucine incorporation) and bacterial abundance (direct counts). Freshwater and marine populations advected into the estuary represented a large fraction of the bacterioplankton community in all seasons. However, a unique estuarine community formed at intermediate salinities in summer and fall, when average doubling time was much shorter than water residence time, but not in spring, when doubling time was similar to residence time. Sequencing of DNA in DGGE bands demonstrated that most bands represented single phylotypes and that matching bands from different samples represented identical phylotypes. Most river and coastal ocean bacterioplankton were members of common freshwater and marine phylogenetic clusters within the phyla Proteobacteria, Bacteroidetes, and ACTINOBACTERIA: Estuarine bacterioplankton also belonged to these phyla but were related to clones and isolates from several different environments, including marine water columns, freshwater sediments, and soil. PMID:15006771
Musilová, Zuzana; Říčan, Oldřich; Janko, Karel; Novák, J.
Roč. 46, - (2008), s. 659-672. ISSN 1055-7903 R&D Projects: GA MŠk LC06073 Grant ostatní: GA UK(CZ) 182/2004/B-BIO; GA UK(CZ) 139407 Institutional research plan: CEZ:AV0Z50450515 Keywords : molecular phylogeny * Cichlids * south America Subject RIV: EG - Zoology Impact factor: 3.871, year: 2008
Stephen J. Ivanyisky III
Full Text Available The Sternarchellini (Gymnotiformes, Apteronotidae is a clade of 10 electric fish species that inhabit deep river channels of the Amazon and Orinoco basins, attain moderate adult body sizes (15-50 cm TL, and have a predatory life style. Here we trace the evolutionary origin and diversification of Sternarchellini using standard phylogenetic and biogeographic procedures and a dataset of 70 morphological characters. The main results are: 1 the genus Sternarchellaincludes both species currently assigned to the genus Magosternarchus; and 2 neither of the multi-species assemblages of Sternarchellini in the Amazon and Orinoco basins are monophyletic. Historical biogeographic analysis suggests that sternarchelline evolution was linked to the large-scale river capture event that formed the modern Amazon and Orinoco basins, i.e. the Late Miocene rise of the Vaupes structural arch and concomitant breaching of the Purus structural arch. This event is hypothesized to have contributed to formation of the modern sternarchelline species, and to the formation of the modern basin-wide sternarchelline species assemblages. The results indicate that cladogenesis (speciation and anagenesis (adaptive evolution were decoupled processes in the evolution of Sternarchellini.
Full Text Available This study assesses the biogeographic classification of the Western Indian Ocean (WIO on the basis of the species diversity and distribution of reef-building corals. Twenty one locations were sampled between 2002 and 2011. Presence/absence of scleractinian corals was noted on SCUBA, with the aid of underwater digital photographs and reference publications for species identification. Sampling effort varied from 7 to 37 samples per location, with 15 to 45 minutes per dive allocated to species observations, depending on the logistics on each trip. Species presence/absence was analyzed using the Bray-Curtis similarity coefficient, followed by cluster analysis and multi-dimensional scaling. Total (asymptotic species number per location was estimated using the Michaelis-Menten equation. Three hundred and sixty nine coral species were named with stable identifications and used for analysis. At the location level, estimated maximum species richness ranged from 297 (Nacala, Mozambique to 174 (Farquhar, Seychelles. Locations in the northern Mozambique Channel had the highest diversity and similarity, forming a core region defined by its unique oceanography of variable meso-scale eddies that confer high connectivity within this region. A distinction between mainland and island fauna was not found; instead, diversity decreased radially from the northern Mozambique Channel. The Chagos archipelago was closely related to the northern Mozambique Channel region, and analysis of hard coral data in the IUCN Red List found Chagos to be more closely related to the WIO than to the Maldives, India and Sri Lanka. Diversity patterns were consistent with primary oceanographic drivers in the WIO, reflecting inflow of the South Equatorial Current, maintenance of high diversity in the northern Mozambique Channel, and export from this central region to the north and south, and to the Seychelles and Mascarene islands.
Stimpson, Christopher M.; Lister, Adrian; Parton, Ash; Clark-Balzan, Laine; Breeze, Paul S.; Drake, Nick A.; Groucutt, Huw S.; Jennings, Richard; Scerri, Eleanor M. L.; White, Tom S.; Zahir, Muhammad; Duval, Mathieu; Grün, Rainer; Al-Omari, Abdulaziz; Al Murayyi, Khalid Sultan M.; Zalmout, Iyaed S.; Mufarreh, Yahya A.; Memesh, Abdullah M.; Petraglia, Michael D.
The current paucity of Pleistocene vertebrate records from the Arabian Peninsula - a landmass of over 3 million km2 - is a significant gap in our knowledge of the Quaternary. Such data are critical lines of contextual evidence for considering animal and hominin dispersals between Africa and Eurasia generally, and hominin palaeoecology in the Pleistocene landscapes of the Arabian interior specifically. Here, we describe an important contribution to the record and report stratigraphically-constrained fossils of mammals, birds and reptiles from recent excavations at Ti's al Ghadah in the southwestern Nefud Desert. Combined U-series and ESR analyses of Oryx sp. teeth indicate that the assemblage is Middle Pleistocene in age and dates to ca. 500 ka. The identified fauna is a biogeographical admixture that consists of likely endemics and taxa of African and Eurasian affinity and includes extinct and extant (or related Pleistocene forms of) mammals (Palaeoloxodon cf. recki, Panthera cf. gombaszogenis, Equus hemionus, cf. Crocuta crocuta, Vulpes sp., Canis anthus, Oryx sp.), the first Pleistocene records of birds from the Arabian Peninsula (Struthio sp., Neophron percnopterus, Milvus cf. migrans, Tachybaptus sp. Anas sp., Pterocles orientalis, Motacilla cf. alba) and reptiles (Varanidae/Uromastyx sp.). We infer that the assemblage reflects mortality in populations of herbivorous animals and their predators and scavengers that were attracted to freshwater and plant resources in the inter-dune basin. At present, there is no evidence to suggest hominin agency in the accumulation of the bone assemblages. The inferred ecological characteristics of the taxa recovered indicate the presence, at least periodically, of substantial water-bodies and open grassland habitats.
C. J. Geldenhuys
Full Text Available Patterns in species richness of 23 small, isolated forests on the inland mountains of the southern Cape were studied. Species richness of woody plants and vines of the Kouga-Baviaanskloof Forests was higher than in the western mountain complexes, where species richness in the more southern Rooiberg and Kamanassie Mountains was higher than in the Swartberg range. The Rooiberg, a dry mountain with small forests far away from the coastal source area, had more species than, and contained many species which are absent from, the larger, moister forests of the Kamanassie which are closest to the coastal source areas. Neither altitude nor distance from the source area, the forests south of the coastal mountains, nor long-distance dispersal, adequately explained the variation in species richness. The variations are best explained in terms of dispersal corridors along the Gouritz and Gamtoos River systems which connect the coastal forests with the inland mountains. The distribution patterns of four species groups in relation to the geomorphological history of the two river systems provide relative dates for the expansion and contraction of temperate forest, subtropical forest and subtropical transitional thicket in the southern Cape.
Frydman, Galit H; Davis, Nick; Beck, Paul L; Fox, James G
Idiopathic thrombocytopenic purpura (ITP) is typically a diagnosis of exclusion, assigned by clinicians after ruling out other identifiable etiologies. Since a report by Gasbarrini et al. in 1998, an accumulating body of evidence has proposed a pathophysiological link between ITP and chronic Helicobacter pylori (H. pylori) infection. Clinical reports have described a spontaneous resolution of ITP symptoms in about 50% of chronic ITP patients following empirical treatment of H. pylori infection, but response appears to be geography dependent. Studies have also documented that ITP patients in East Asian countries are more likely to express positive antibody titers against H. pylori-specific cytotoxic-associated gene A (CagA), a virulence factor that is associated with an increased risk for gastric diseases including carcinoma. While a definitive mechanism by which H. pylori may induce thrombocytopenia remains elusive, proposed pathways include molecular mimicry of CagA by host autoantibodies against platelet surface glycoproteins, as well as perturbations in the phagocytic activity of monocytes. Traditional treatments of ITP have been largely empirical, involving the use of immunosuppressive agents and immunoglobulin therapy. However, based on the findings of clinical reports emerging over the past 20 years, health organizations around the world increasingly suggest the detection and eradication of H. pylori as a treatment for ITP. Elucidating the exact molecular mechanisms of platelet activation in H. pylori-positive ITP patients, while considering biogeographical differences in response rates, could offer insight into how best to use clinical H. pylori eradication to treat ITP, but will require well-designed studies to confirm the suggested causative relationship between bacterial infection and an autoimmune disease state. PMID:25728540
Hibbs, Douglas A.; Olsson, Ola
The most important event in human economic history before the industrial revolution was the Neolithic transition from a nomadic hunter-gatherer lifestyle to sedentary agriculture, beginning ≈10,000 years ago. The transition made possible the human population explosion, the rise of non-food-producing specialists, and the acceleration of technological progress that led eventually to the industrial revolution. But the transition occurred at different times in different regions of the world, with...
Veith, M.; Fromhage, L.; Kosuch, J.; Vences, M.
Spadefoot toads (Pelobates) and Parsley frogs (Pelodytes) are an enigmatic group of Western Palaearctic anurans. In the genus Pelobates, a fossorial lifestyle has enforced a conserved bauplan that masks their intraspecific evolutionary history. We used partial sequences of the mitochondrial 16S and
Veith, M.; Fromhage, L.; Kosuch, J.; Vences, M.
Abstract Spadefoot toads (Pelobates) and Parsley frogs (Pelodytes) are an enigmatic group of Western Palaearctic anurans. In the genus Pelobates, a fossorial lifestyle has enforced a conserved bauplan that masks their intraspecific evolutionary history. We used partial sequences of the mitochondrial 16S and 12S rRNA genes to infer a paleobiogeographic scenario of speciation events in these two anuran genera. Based on two alternative, mutually exclusive calibrations of the Iberian-African spli...
National Oceanic and Atmospheric Administration, Department of Commerce — This dataset represents sediment composition class predictions from a sediment spatial model developed for the New York offshore spatial planning area. The...
Full Text Available BACKGROUND: Biogeographic models partition ecologically similar species assemblages into discrete ecoregions. However, the history, relationship and interactions between these regions and their assemblages have rarely been explored. METHODOLOGY/PRINCIPAL FINDINGS: Here we develop a taxon-based approach that explicitly utilises molecular information to compare ecoregion history and status, which we exemplify using a continentally distributed mammalian species: the African bushbuck (Tragelaphus scriptus. We reveal unprecedented levels of genetic diversity and structure in this species and show that ecoregion biogeographic history better explains the distribution of molecular variation than phenotypic similarity or geography. We extend these data to explore ecoregion connectivity, identify core habitats and infer ecological affinities from them. CONCLUSIONS/SIGNIFICANCE: This analysis defines 28 key biogeographic regions for sub-Saharan Africa, and provides a valuable framework for the incorporation of genetic and biogeographic information into a more widely applicable model for the conservation of continental biodiversity.
Tershy, Bernie R.; Newton, Kelly M.; Spatz, Dena R.; Swinnerton, Kirsty; Iverson, John B.; Fisher, Robert N.; Harlow, Peter S.; Holmes, Nick D.; Croll, Donald A.
Iguanas are a particularly threatened group of reptiles, with 61% of species at risk of extinction. Primary threats to iguanas include habitat loss, direct and indirect impacts by invasive vertebrates, overexploitation, and human disturbance. As conspicuous, charismatic vertebrates, iguanas also represent excellent flagships for biodiversity conservation. To assist planning for invasive vertebrate management and thus benefit threatened iguana recovery, we identified all islands with known extant or extirpated populations of Critically Endangered and Endangered insular iguana taxa as recognized by the International Union for Conservation of Nature (IUCN) Red List of Threatened Species. For each island, we determined total area, sovereignty, the presence of invasive alien vertebrates, and human population. For the 23 taxa of threatened insular iguanas we identified 230 populations, of which iguanas were extant on 185 islands and extirpated from 45 islands. Twenty-one iguana taxa (91% of all threatened insular iguana taxa) occurred on at least one island with invasive vertebrates present; 16 taxa had 100% of their population(s) on islands with invasive vertebrates present. Rodents, cats, ungulates, and dogs were the most common invasive vertebrates. We discuss biosecurity, eradication, and control of invasive vertebrates to benefit iguana recovery: (1) on islands already free of invasive vertebrates; (2) on islands with high iguana endemicity; and (3) for species and subspecies with small total populations occurring across multiple small islands. Our analyses provide an important first step toward understanding how invasive vertebrate management can be planned effectively to benefit threatened insular iguanas.
Full Text Available Chagas disease control strategies strongly depend on the triatomine vector species involved in Trypanosoma cruzi transmission within each area. Here we report the results of the identification of specimens belonging to various species of Triatominae captured in Ecuador (15 species from 17 provinces and deposited in the entomological collections of the Catholic University of Ecuador (Quito, Instituto Oswaldo Cruz (Brazil, the Natural History Museum London (UK, the London School of Hygiene and Tropical Medicine (UK, the National Institute of Hygiene (Quito, and the Vozandes Hospital (Quito. A critical review of published information and new field records are presented. We analysed these data in relation to the life zones where triatomines occur (11 life zones, excluding those over 2,200 m altitude, and provide biogeographical maps for each species. These records are discussed in terms of epidemiological significance and design of control strategies. Findings relevant to the control of the main vector species are emphasised. Different lines of evidence suggest that Triatoma dimidiata is not native to Ecuador-Peru, and that synanthropic populations of Rhodnius ecuadoriensis in southern Ecuador-northern Peru might be isolated from their sylvatic conspecifics. Local eradication of T. dimidiata and these R. ecuadoriensis populations might therefore be attainable. However, the presence of a wide variety of native species indicates the necessity for a strong longitudinal surveillance system.
Anderson, Gregory J.
Full Text Available The endemic and rare Solanum vespertilio and S. lidii from the Canary Islands are notable in being andromonoecious, self compatible, highly heterandrous (with short >reward= anthers and one very long >pollination= anther, and bearing strongly zygomorphic corollas. Solanum vespertilio flowers are also tetramerous, and some display enantiostyly. Given their island distribution, uncommon for solanums, and many distinctive reproductive features, the phylogenetic position is of interest. With new molecular data from the chloroplast trnT-F region and the nuclear granule-bound starch synthase gene (GBSSI or waxy, we confirm the hypothesis that these two species are phylogenetically associated with Solanum lineages from Africa, rather than with previously suggested Mexican species. The phylogeny facilitates understanding the evolution of the unique suite of reproductive characteristics in these island endemics.Las endémicas y raras especies Solanum vespertilio y S. lidii de las Islas Canarias son notables por ser andromonoicas, autocompatibles, altamente heterándricas (con anteras cortas para recompensa y una muy larga para polinización y por tener corolas fuertemente zigomórficas. Las flores de Solanum vespertilio son, además, tetrámeras y muestran enantiostilia. Dada su distribución insular, poco común para Solanum, y sus distintivas características reproductivas, su posición filogenética es de interés. Con nuevos datos moleculares de la región trnT-F del ADN del cloroplasto y del gen nuclear de la enzima almidón sintasa unida al gránulo (GBSSI o waxy, confirmamos la hipótesis de que estas dos especies están filogenéticamente asociadas con los linajes geográficamente próximos de Solanum africanos, más que con especies mexicanas previamente sugeridas. La filogenia facilita la comprensión de la evolución del conjunto singular de características reproductivas de estas especies endémicas de islas.
Wernberg, Thomas; Thomsen, Mads S.; Connell, Sean D.; Russell, Bayden D.; Waters, Jonathan M.; Zuccarello, Giuseppe C.; Kraft, Gerald T.; Sanderson, Craig; West, John A.; Gurgel, Carlos F. D.
Explaining spatial patterns of biological organisation remains a central challenge for biogeographic studies. In marine systems, large-scale ocean currents can modify broad-scale biological patterns by simultaneously connecting environmental (e.g. temperature, salinity and nutrients) and biological (e.g. amounts and types of dispersed propagules) properties of adjacent and distant regions. For example, steep environmental gradients and highly variable, disrupted flow should lead to heterogene...
Loehle, C. [Argonne National Lab., IL (United States). Environmental Research Div.; Iltis, H. [Univ. of Wisconsin, Madison, WI (United States). Dept. of Botany
The current reconstruction of the vegetation of eastern North America at the last glacial maximum postulates a very wide zone of tundra and boreal forest south of the ice. This reconstruction requires that the deciduous forest retreated far to the south. The authors believe that this reconstruction is seriously in error. Geologic evidence for glacial activity or tundra is absent from the southern Appalachians. Positive evidence for boreal forest is based on pollen identifications for Picea, Betula, and Pinus, when in reality southern members of these genera have pollen that cannot be distinguished from that of northern members. Further, pollen of typical southern species such as oaks and hickories occurs throughout profiles that past authors had labeled boreal. Pollen evidence for a far southern deciduous forest refuge is lacking. Data on endemics are particularly challenging for the scenario in which deciduous forest migrated to the south and back. The southern Appalachian region is rife with endemics that are often extreme-habitat specialists unable to migrate. The previously glaciated zone is almost completely lacking in endemics. Outlier populations, range boundaries, and absence of certain hybrids all argue against a large boreal zone. The new reconstruction postulates a cold zone no more than 75--100 miles wide south of the ice in the East.
Species of the genus Pontonia Latreille, 1829, are distributed in tropical and subtropical waters around the world, living in association with either molluscan or ascidian hosts. In the present taxonomic revision, Pontonia sensu lato is divided into six genera: Pontonia sensu stricto; Ascidonia gen. nov., Rostronia gen. nov., Dactylonia gen. nov., Odontonia gen. nov., and Bruceonia gen. nov. A total of 29 species is described and figured, four of which are new to science: Pontonia pilosa spec...
Normand, Philippe; Lapierre, Pascal; Tisa, Louis S.; Gogarten, J.Peter; Alloisio, Nicole; Bagnarol, Emilie; Bassi, Carla A.; Berry,Alison; Bickhart, Derek M.; Choisne, Nathalie; Couloux, Arnaud; Cournoyer, Benoit; Cruveiller, Stephane; Daubin, Vincent; Demange, Nadia; Francino, M. Pilar; Ggoltsman, Eugene; Huang, Ying; Kopp, Olga; Labarre,Laurent; Lapidus, Alla; Lavire, Celine; Marechal, Joelle; Martinez,Michele; Mastronunzio, Juliana E.; Mullin, Beth; Niemann, James; Pujic,Pierre; Rawnsley, Tania; Rouy, Zoe; Schenowitz, Chantal; Sellstedt,Anita; Tavares, Fernando; Tomkins, Jeffrey P.; Vallenet, David; Valverde,Claudio; Wall, Luis; Wang, Ying; Medigue, Claudine; Benson, David R.
Filamentous actinobacteria from the genus Frankia anddiverse woody trees and shrubs together form N2-fixing actinorhizal rootnodule symbioses that are a major source of new soil nitrogen in widelydiverse biomes 1. Three major clades of Frankia sp. strains are defined;each clade is associated with a defined subset of plants from among theeight actinorhizal plant families 2,3. The evolution arytrajectoriesfollowed by the ancestors of both symbionts leading to current patternsof symbiont compatibility are unknown. Here we show that the competingprocesses of genome expansion and contraction have operated in differentgroups of Frankia strains in a manner that can be related to thespeciation of the plant hosts and their geographic distribution. Wesequenced and compared the genomes from three Frankia sp. strains havingdifferent host plant specificities. The sizes of their genomes variedfrom 5.38 Mbp for a narrow host range strain (HFPCcI3) to 7.50Mbp for amedium host range strain (ACN14a) to 9.08 Mbp for a broad host rangestrain (EAN1pec.) This size divergence is the largest yet reported forsuch closely related bacteria. Since the order of divergence of thestrains is known, the extent of gene deletion, duplication andacquisition could be estimated and was found to be inconcert with thebiogeographic history of the symbioses. Host plant isolation favoredgenome contraction, whereas host plant diversification favored genomeexpansion. The results support the idea that major genome reductions aswell as expansions can occur in facultatively symbiotic soil bacteria asthey respond to new environments in the context of theirsymbioses.
This study assesses the biogeographic classification of the Western Indian Ocean (WIO) on the basis of the species diversity and distribution of reef-building corals. Twenty one locations were sampled between 2002 and 2011. Presence/absence of scleractinian corals was noted on SCUBA, with the aid of underwater digital photographs and reference publications for species identification. Sampling effort varied from 7 to 37 samples per location, with 15 to 45 minutes per dive allocated to species ...
Gudynas, E.; Williams, J.D.; Mercedes Azpelicueta, de las M.
This study of Chthonerpeton indistinctum (Reinhardt & Lütken, 1861) considers 25 morphometric characters, teeth-counts and sex, based on 96 specimens. A multivariate analysis of characters and comparisons of geographically arranged samples is carried out by graphic and statistical methods. No trends
Yan-Wen Cai; Xin-Yue Cheng; Ru-Mei Xu; Dong-Hong Duan; Lawrence R. Kirkendall
Sequences of 479 bp region of the mitochondrial COI gene were applied to detect population genetic diversity and structure of Dendroctonus valens populations. By comparing the genetic diversity between native and invasive populations, it was shown that the genetic diversity of Chinese populations was obviously lower than that of native populations with both indices of haplotype diversity and Nei's genetic diversity, suggesting genetic bottleneck occurred in the invasive process of D. valens, and was then followed by a relatively quick population buildup. According to phylogenetic analyses of haplotypes, we suggested that the origin of the Chinese population was from California, USA. Phylogenetic and network analysis of native populations of D. valens revealed strong genetic structure at two distinct spatial and temporal scales in North America. The main cause resulting in current biogeographic pattern was supposedly due to recycled glacial events. Meanwhile, a cryptic species might exist in the Mexican and Guatemalan populations.
Goicoechea, Noemí; Padial, José M; Chaparro, Juan C; Castroviejo-Fisher, Santiago; De la Riva, Ignacio
The family Gymnophthalmidae comprises ca. 220 described species of Neotropical lizards distributed from southern Mexico to Argentina. It includes 36 genera, among them Proctoporus, which contains six currently recognized species occurring across the yungas forests and wet montane grasslands of the Amazonian versant of the Andes from central Peru to central Bolivia. Here, we investigate the phylogenetic relationships and species limits of Proctoporus and closely related taxa by analyzing 2121 base pairs of mitochondrial (12S, 16S, and ND4) and nuclear (c-mos) genes. Our taxon sampling of 92 terminals includes all currently recognized species of Proctoporus and 15 additional species representing the most closely related groups to the genus. Maximum parsimony, maximum likelihood and Bayesian phylogenetic analyses recovered a congruent, fully resolved, and strongly supported hypothesis of relationships that challenges previous phylogenetic hypotheses and classifications, and biogeographic scenarios. Our main results are: (i) discovery of a strongly supported clade that includes all species of Proctoporus and within which are nested the monotypic Opipeuter xestus (a genus that we consider a junior synonym of Proctoporus), and two species of Euspondylus, that are therefore transferred to Proctoporus; (ii) the paraphyly of Proctoporus bolivianus with respect to P. subsolanus, which is proposed as a junior synonym of P. bolivianus; (iii) the detection of seven divergent and reciprocally monophyletic lineages (five of them previously assigned to P. bolivianus) that are considered confirmed candidate species, which implies that more candidate species are awaiting formal description and naming than currently recognized species in the genus; (iv) rejection of the hypothesis that Proctoporus diversified following a south to north pattern parallel to the elevation of the Andes; (v) species diversity in Proctoporus is the result of in situ diversification through vicariance in the grasslands of the high Andes, with at least five dispersals contributing to montane forest species. PMID:22982151
Shibl, Ahmed A.
Aquatic primary productivity mainly depends on pelagic phytoplankton. The globally abundant marine picocyanobacteria Prochlorococcus comprises a significant fraction of the photosynthetic biomass in most tropical, oligotrophic oceans. The Red Sea is an enclosed narrow body of water characterized by continuous solar irradiance, and negligible annual rainfall, in addition to elevated temperatures and salinity levels, which mimics a global warming scenario. Analysis of 16S rRNA sequences of bacterioplankton communities indicated the predominance of a high-light adapted ecotype (HL II) of Prochlorococcus at the surface of the Northern and Central Red Sea. To this end, we analyzed the distribution of Prochlorococcus at multiple depths within and below the euphotic zone in different regions of the Red Sea, using clone libraries of the 16S–23S rRNA internal transcribed spacer (ITS) region. Results indicated a high diversity of Prochlorococcus ecotypes at the 100 m depth in the water column and an unusual dominance of HL II-related sequences in deeper waters of the Red Sea. To further investigate the microdiversity of Prochlorococcus over a wider biogeographical scope, we used a 454-pyrosequencing approach to analyze rpoC1 gene pyrotags. Samples were collected from the surface of the water column to up to 500 m at 45 stations that span the Red Sea’s main basin from 4 north to south. Phylogenetic analysis of abundant rpoC1 OTUs revealed genotypes of recently discovered strains that belong to the high-light and lowlight clades. In addition, we used a rapid community-profiling tool (GraftM) and quantitatively analyzed rpoC1 gene abundance from 45 metagenomes to assess the Prochlorococcus community structure across vertical and horizontal physicochemical gradients. Results revealed the clustering of samples according to their depth and a strong influence on ecotypic distribution by temperature and oxygen levels. In efforts to better understand how the cells survive the unusual features of the Red Sea, a Prochlorococcus strain of the HL II adapted clade from the euphotic zone was cultured, enabling morphological analyses and growth rates measurements for the strain. In addition, we successfully sequenced and annotated the genome of the strain, which was then used for genomic comparison with other ecotypes. Interestingly, the set of unique genes identified in the draft genome included genes encoding proteins involved in salt tolerance mechanisms. The expression level and pattern of these genes in the Red Sea water column was explored through metatranscriptomic mapping and revealed their occurrence throughout, independent of the diel cycle. This led to the hypothesis that Prochlorococcus populations in the highly saline Red Sea are able to biosynthesize additional compatible solutes via several pathways to counterbalance the effects of salt stress. The results presented in this dissertation provide the first glimpse on how the environmental parameters of the Red Sea can affect the evolution, diversity and distribution patterns of Prochlorococcus ecotypes.
Full Text Available Knowledge on spatial scales of the distribution of deep-sea life is still sparse, but highly relevant to the understanding of dispersal, habitat ranges and ecological processes. We examined regional spatial distribution patterns of the benthic bacterial community and covarying environmental parameters such as water depth, biomass and energy availability at the Arctic Long-Term Ecological Research (LTER site HAUSGARTEN (Eastern Fram Strait. Samples from 13 stations were retrieved from a bathymetric (1,284-3,535 m water depth, 54 km in length and a latitudinal transect (∼ 2,500 m water depth; 123 km in length. 454 massively parallel tag sequencing (MPTS and automated ribosomal intergenic spacer analysis (ARISA were combined to describe both abundant and rare types shaping the bacterial community. This spatial sampling scheme allowed detection of up to 99% of the estimated richness on phylum and class levels. At the resolution of operational taxonomic units (97% sequence identity; OTU3% only 36% of the Chao1 estimated richness was recovered, indicating a high diversity, mostly due to rare types (62% of all OTU3%. Accordingly, a high turnover of the bacterial community was also observed between any two sampling stations (average replacement of 79% of OTU3%, yet no direct correlation with spatial distance was observed within the region. Bacterial community composition and structure differed significantly with increasing water depth along the bathymetric transect. The relative sequence abundance of Verrucomicrobia and Planctomycetes decreased significantly with water depth, and that of Deferribacteres increased. Energy availability, estimated from phytodetrital pigment concentrations in the sediments, partly explained the variation in community structure. Overall, this study indicates a high proportion of unique bacterial types on relatively small spatial scales (tens of kilometers, and supports the sampling design of the LTER site HAUSGARTEN to study bacterial community shifts in this rapidly changing area of the world's oceans.
Kawahara, Akito Y.; Mignault, Andre A.; Regier, Jerome C; Ian J Kitching; Mitter, Charles
Background The 1400 species of hawkmoths (Lepidoptera: Sphingidae) comprise one of most conspicuous and well-studied groups of insects, and provide model systems for diverse biological disciplines. However, a robust phylogenetic framework for the family is currently lacking. Morphology is unable to confidently determine relationships among most groups. As a major step toward understanding relationships of this model group, we have undertaken the first large-scale molecular phylogenetic analys...
Dijkstra, Klaas-Douwe Benediktus
Africa has a large and almost uninterrupted land surface that is isolated from surrounding continents. In the last 20 million years Africa had a variable and increasingly dry climate. As a result the Afrotropics have only half as many odonate species as tropical America or Asia. ‘Relict’ families ar
Ridder-Numan, Jeannette W.A.
The genera Butea, Meizotropis and Spatholobus (Leguminosae—Papilionoideae), occurring in continental Southeast Asia and the West Malesian Archipelago, are treated phylogenetically with Kunstleria as an outgroup. The genera Spatholobus (29 species), Butea and Meizotropis (each 2 species) are usually placed in the tribe Phaseoleae of the Papilionoideae, whereas Kunstleria belongs to the less advanced tribe Millettieae. Spatholobus is probably basal in the Phaseoleae. An analysis with PAUP of th...
Milici, Mathias; Tomasch, Jürgen; Wos-Oxley, Melissa L.; Decelle, Johan; Jáuregui, Ruy; Wang, Hui; Deng, Zhi-Luo; Plumeier, Iris; Giebel, Helge-Ansgar; Badewien, Thomas H.; Wurst, Mascha; Pieper, Dietmar H.; Simon, Meinhard; Wagner-Döbler, Irene
In order to determine the influence of geographical distance, depth, and Longhurstian province on bacterial community composition and compare it with the composition of photosynthetic micro-eukaryote communities, 382 samples from a depth-resolved latitudinal transect (51°S–47°N) from the epipelagic zone of the Atlantic ocean were analyzed by Illumina amplicon sequencing. In the upper 100 m of the ocean, community similarity decreased toward the equator for 6000 km, but subsequently increased again, reaching similarity values of 40–60% for samples that were separated by ~12,000 km, resulting in a U-shaped distance-decay curve. We conclude that adaptation to local conditions can override the linear distance-decay relationship in the upper epipelagial of the Atlantic Ocean which is apparently not restrained by barriers to dispersal, since the same taxa were shared between the most distant communities. The six Longhurstian provinces covered by the transect were comprised of distinct microbial communities; ~30% of variation in community composition could be explained by province. Bacterial communities belonging to the deeper layer of the epipelagic zone (140–200 m) lacked a distance-decay relationship altogether and showed little provincialism. Interestingly, those biogeographical patterns were consistently found for bacteria from three different size fractions of the plankton with different taxonomic composition, indicating conserved underlying mechanisms. Analysis of the chloroplast 16S rRNA gene sequences revealed that phytoplankton composition was strongly correlated with both free-living and particle associated bacterial community composition (R between 0.51 and 0.62, p < 0.002). The data show that biogeographical patterns commonly found in macroecology do not hold for marine bacterioplankton, most likely because dispersal and evolution occur at drastically different rates in bacteria. PMID:27199923
DeBruyn, Jennifer M.; Nixon, Lauren T.; Fawaz, Mariam N.; Johnson, Amy M.; Radosevich, Mark
Bacteria belonging to phylum Gemmatimonadetes comprise approximately 2% of soil bacterial communities. However, little is known of their ecology due to a lack of cultured representation. Here we present evidence from biogeographical analyses and seasonal quantification of Gemmatimonadetes in soils, which suggests an adaptation to low soil moisture.
Albouy, C; Guilhaumon, François; Leprieur, F; Lasram, F. B.; Somot, S.; Aznar, R; Velez, Laure; Le Loc'h, François; Mouillot, D.
Aim To forecast the potential effects of climate change in the Mediterranean Sea on the species richness and mean body size of coastal fish assemblages. Location The Mediterranean Sea. Methods Using an ensemble forecasting approach, we used species distribution modelling to project the potential distribution of 288 coastal fish species by the middle and end of the 21st century based on the IPCC A2 scenario implemented with the Mediterranean climatic model NEMOMED8. Results A mean rise of 1.4 ...
Morwood, M J; Jungers, W L
Excavations at Liang Bua, on the Indonesian island of Flores, have yielded a stratified sequence of stone artifacts and faunal remains spanning the last 95k.yr., which includes the skeletal remains of two human species, Homo sapiens in the Holocene and Homo floresiensis in the Pleistocene. This paper summarizes and focuses on some of the evidence for Homo floresiensis in context, as presented in this Special Issue edition of the Journal of Human Evolution and elsewhere. Attempts to dismiss the Pleistocene hominins (and the type specimen LB1 in particular) as pathological pygmy humans are not compatible with detailed analyses of the skull, teeth, brain endocast, and postcranium. We initially concluded that H. floresiensis may have evolved by insular dwarfing of a larger-bodied hominin species over 880k.yr. or more. However, recovery of additional specimens and the numerous primitive morphological traits seen throughout the skeleton suggest instead that it is more likely to be a late representative of a small-bodied lineage that exited Africa before the emergence of Homo erectus sensu lato. Homo floresiensis is clearly not an australopithecine, but does retain many aspects of anatomy (and perhaps behavior) that are probably plesiomorphic for the genus Homo. We also discuss some of the other implications of this tiny, endemic species for early hominin dispersal and evolution (e.g., for the "Out of Africa 1" paradigm and more specifically for colonizing Southeast Asia), and we present options for future research in the region. PMID:19913680
Janssens, Steven B; Groeninckx, Inge; De Block, Petra J; Verstraete, Brecht; Smets, Erik F; Dessein, Steven
Despite the close proximity of the African mainland, dispersal of plant lineages towards Madagascar remains intriguing. The composition of the Madagascan flora is rather mixed and shows besides African representatives, also floral elements of India, Southeast Asia, Australia, and the Neotropics. Due to its proportionally large number of Madagascan endemics, the taxonomically troublesome Spermacoceae tribe is an interesting group to investigate the origin and evolution of the herbaceous Rubiaceae endemic to Madagascar. The phylogenetic position of these endemics were inferred using four plastid gene markers. Age estimates were obtained by expanding the Spermacoceae dataset with representatives of all Rubiaceae tribes. This allowed incorporation of multiple fossil-based calibration points from the Rubiaceae fossil record. Despite the high morphological diversity of the endemic herbaceous Spermacoceae on Madagascar, only two colonization events gave rise to their current diversity. The first clade contains Lathraeocarpa, Phylohydrax and Gomphocalyx, whereas the second Madagascan clade includes the endemic genera Astiella, Phialiphora, Thamnoldenlandia and Amphistemon. The tribe Spermacoceae is estimated to have a Late Eocene origin, and diversified during Oligocene and Miocene. The two Madagascan clades of the tribe originated in the Oligocene and radiated in the Miocene. The origin of the Madagascan Spermacoceae cannot be explained by Gondwanan vicariance but only by means of Cenozoic long distance dispersal events. Interestingly, not only colonization from Africa occurred but also long distance dispersal from the Neotropics shaped the current diversity of the Spermacoceae tribe on Madagascar. PMID:26639100
Carotenuto, F; Tsikaridze, N; Rook, L; Lordkipanidze, D; Longo, Laura; Condemi, Silvana; Raia, P
The dispersal of Homo erectus out of Africa at some 1.9 million years ago is one of the most important, crucial, and yet controversial events in human evolution. Current opinions about this episode expose the contrast between those who see H. erectus as a highly social, cooperative species seeking out new ecological opportunities to exploit, and those preferring a passive, climate driven explanation for such an event. By using geostatistics techniques and probabilistic models, we characterised the ecological context of H. erectus dispersal, from its East African origin to the colonization of Eurasia, taking into account both the presence of other large mammals and the physical characteristics of the landscape as potential factors. Our model indicated that H. erectus followed almost passively the large herbivore fauna during its dispersal. In Africa, the dispersal was statistically associated with the presence of large freshwater bodies (Rift Valley Lakes). In Eurasia, the presence of H. erectus was associated with the occurrence of geological outcrops likely yielding unconsolidated flint. During the early phase of dispersal, our model indicated that H. erectus actively avoided areas densely populated by large carnivores. This pattern weakened as H. erectus dispersed over Europe, possibly because of the decreasing presence of carnivores there plus the later acquisition of Acheulean technology. During this later phase, H. erectus was associated with limestone and shaley marl, and seems to have been selecting for high-elevation sites. While our results do not directly contradict the idea that H. erectus may have been an active hunter, they clearly point to the fact that predator avoidance may have conditioned its long-distance diffusion as it moved outside Africa. The modelled dispersal route suggests that H. erectus remained preferentially associated with low/middle latitude (i.e., comparatively warm) sites throughout its colonization history. PMID:27260171
Treseder, KK; Maltz, MR; Hawkins, BA; Fierer, N.; Stajich, JE; Mcguire, KL
Although fungal communities are known to vary along latitudinal gradients, mechanisms underlying this pattern are not well-understood. We used high-throughput sequencing to examine the large-scale distributions of soil fungi and their relation to evolutionary history. We tested the Tropical Conservatism Hypothesis, which predicts that ancestral fungal groups should be more restricted to tropical latitudes and conditions than would more recently derived groups. We found support for this hypoth...
Jelić, Mišel; Klobučar, Göran I V; Grandjean, Frédéric; Puillandre, Nicolas; Franjević, Damjan; Futo, Momir; Amouret, Julien; Maguire, Ivana
In this study, the evolutionary history of the white-clawed crayfish (WCC) was evaluated using large-scale datasets comprising >1350 specimens from the entire distribution range. Using species delimitation methods on mitochondrial DNA (mtDNA) sequences, we propose four primary species hypotheses for WCC. Sequences for several nuclear regions were screened but none showed significant variation within WCC. This result favours a single secondary species hypothesis and indicates the existence of a mito-nuclear discordance in WCC. Therefore, mtDNA groups were considered only as genetic units that carry information about ancient divergences within WCC and not as taxonomic units. The reconstruction of ancestral ranges and divergence time estimates were used to link the current genetic structure with paleogeographic processes. These results showed that the emergence of mtDNA groups in WCC could be related to the Messinian Salinity Crisis, the climate cooling during the Pliocene and Pleistocene, and (paleo)shifting of the Adriatic Sea coastline in the Padanovenezian Plain. The most recent common ancestor of the mtDNA groups most likely originated from Dalmatia (eastern Adriatic coast) as indicated by the reconstruction of ancestral ranges. This ecoregion, along with the Gulf of Venice Drainages, harbours a high genetic diversity and should be emphasised as an area of the highest conservation priority. PMID:27404041
Mueller, Rachel Lockridge; Macey, J. Robert; Jaekel, Martin; Wake, David B.; Boore, Jeffrey L.
The evolutionary history of the largest salamander family (Plethodontidae) is characterized by extreme morphological homoplasy. Analysis of the mechanisms generating such homoplasy requires an independent, molecular phylogeny. To this end, we sequenced 24 complete mitochondrial genomes (22 plethodontids and two outgroup taxa), added data for three species from GenBank, and performed partitioned and unpartitioned Bayesian, ML, and MP phylogenetic analyses. We explored four dataset partitioning strategies to account for evolutionary process heterogeneity among genes and codon positions, all of which yielded increased model likelihoods and decreased numbers of supported nodes in the topologies (PP > 0.95) relative to the unpartitioned analysis. Our phylogenetic analyses yielded congruent trees that contrast with the traditional morphology-based taxonomy; the monophyly of three out of four major groups is rejected. Reanalysis of current hypotheses in light of these new evolutionary relationships suggests that (1) a larval life history stage re-evolved from a direct-developing ancestor multiple times, (2) there is no phylogenetic support for the ''Out of Appalachia'' hypothesis of plethodontid origins, and (3) novel scenarios must be reconstructed for the convergent evolution of projectile tongues, reduction in toe number, and specialization for defensive tail loss. Some of these novel scenarios imply morphological transformation series that proceed in the opposite direction than was previously thought. In addition, they suggest surprising evolutionary lability in traits previously interpreted to be conservative.
Dora Nancy Padilla Gil
Full Text Available Este análisis biogeográfico examina los procesos históricos, geológicos, climáticos y ecológicos que han influido en la formación de los bosques tropicales secos (DTF de Mesoamérica y Colombia, bosques que son sitios de múltiples historias biogeográficas como la que ilustran los Canthonini. Sometemos a prueba la hipótesis de que la fauna de Canthonini de los bosques tropicales secos tiene una afinidad sudamericana. Para este propósito comparamos las especies que se encuentran en un enclave de bosque tropical seco en México, en un segundo enclave en Costa Rica, en cuatro de la región Caribe de Colombia y finalmente uno más en el norte de Tolima en el valle superior del río Magdalena, Colombia. Las características geomorfológicas de los enclaves son también comparadas, así como la distribución geográfica y las afinidades taxonómicas de cada una de las especies de Canthonini que se encuentran en estos bosques tropicales secos. Los aspectos de historia biogeográfica, geológica y ecológica de los enclaves son evaluados usando un Análisis de Parsimonia de Endemicidad (PAE, utilizando como grupo externo dos lugares de selva siempre verde: Leticia (Amazonas, Colombia y Los Tuxtlas (Veracruz, México. Este estudio pone de manifiesto que el origen y distribución de los bosques tropicales secos de la región ocurre durante el Pleistoceno, con una acentuación de las características de sequía durante el Holoceno. También revela similitudes entre los Canthonini de los bosques tropicales secos de México, Costa Rica y Colombia, con tres patrones de distribución que corresponden a diferentes grados de expansión hacia el norte y a la diversificación de líneas evolutivas, incluso a la presencia de especies sudamericanas. La comparación entre el cladograma generado por las especies de Canthonini y el de eventos geológicos, indica que la distribución de los primeros en los bosques tropicales secos comienza en el Plioceno con el restablecimiento de la conexión panameña, sin evidencias de que eventos geomorfológicos previos hayan ejercido influencias. Por otra parte, hay muy pocas especies compartidas con las selvas siempre verdes usadas como grupo externo en los cladogramas.
Dora Nancy Padilla-Gil; Gonzalo Halffter
Este análisis biogeográfico examina los procesos históricos, geológicos, climáticos y ecológicos que han influido en la formación de los bosques tropicales secos (DTF) de Mesoamérica y Colombia, bosques que son sitios de múltiples historias biogeográficas como la que ilustran los Canthonini. Sometemos a prueba la hipótesis de que la fauna de Canthonini de los bosques tropicales secos tiene una afinidad sudamericana. Para este propósito comparamos las especies que se encuentran en ...
Dora Nancy Padilla-Gil
Full Text Available This biogeographical analysis examines the historical, geological, climatic and ecological processes that have influenced the formation of the dry tropical forests (DTF of Mesoamerica and Colombia, areas that are the setting for multiple biogeographical stories that in this case are illustrated by the patterns and evolutionary processes of Canthonini. In this study we test the hypothesis that the Canthonini fauna of dry tropical forests has a South American affinity. To this end, we compare extant species from a tract of dry tropical forest in Mexico, a second enclave in Costa Rica, four from the Caribbean region of Colombia and finally one from the north of Tolima in the Upper Magdalena River Valley, Colombia. The geomorphological characteristics of the enclaves of DTF are also compared, as are the geographical distribution and taxonomic affinities of each of the species found in these dry tropical forests. The biogeographical, historical and geological aspects of the enclaves were evaluated using a Parsimony Analysis of Endemicity (PAE, with two tropical rain forests as the outgroup: Leticia (Amazonas, Colombia and Los Tuxtlas (Veracruz, Mexico. This study reveals the origin and distribution of Neotropical dry forests in the Pleistocene, and the establishment of its dry conditions during the Holocene. It also reveals apparent similarities among the Canthonini of the dry tropical forests of Mexico, Costa Rica and Colombia, with three geographical distribution patterns that correspond to different degrees of expansion towards the north and the diversification of evolutionary lines, and even species of South American origin. The comparison of the cladogram generated for species of Canthonini with that of the geological events that have occurred in the study regions indicates that the distribution of Canthonini in dry tropical forests began during the Pliocene with the re-establishment of the Panamanian connection, with no evidence of previous geomorphological events having any influence. On the other hand, there are few species shared with the tropical rain forests used as the outgroup for the cladograms.
We consider a branching process with Poissonian immigration where individuals have inheritable types. At rate $\\theta$, new individuals singly enter the total population and start a new population which evolves like a supercritical, homogeneous, binary Crump-Mode-Jagers process: individuals have i.i.d. lifetimes durations (non necessarily exponential) during which they give birth independently at constant rate b. First, using spine decomposition, we relax previously known assumptions required for a.s. convergence of total population size. Then, we consider three models of structured populations: either all immigrants have a different type, or types are drawn in a discrete spectrum or in a continuous spectrum. In each model, the vector (P_1,P_2,...) of relative abundances of surviving families converges a.s. In the first model, the limit is the GEM distribution with parameter $\\theta/b$.
Carnicer, Jofre; Brotons, Lluis; Stefanescu, Constanti; Penuelas, Josep
Here we review how adaptive traits contribute to the emergence and maintenance of species richness gradients through their influence on demographic and diversification processes. We start by reviewing how demographic dynamics change along species richness gradients. Empirical studies show that geogr
Xavier, Ariane Lima; Guedes, Thaís Barreto; Napoli, Marcelo Felgueiras
The east coast of Brazil comprises an extensive area inserted in the Tropical Atlantic Domain and is represented by sandy plains of beach ridges commonly known as Restingas. The coastal environments are unique and house a rich amphibian fauna, the geographical distribution patterns of which are incipient. Biogeographical studies can explain the current distributional patterns and provide the identification of natural biogeographical units. These areas are important in elucidating the evolutionary history of the taxa and the areas where they occur. The aim of this study was to seek natural biogeographical units in the Brazilian sandy plains of beach ridges by means of distribution data of amphibians and to test the main predictions of the vicariance model to explain the patterns found. We revised and georeferenced data on the geographical distribution of 63 anuran species. We performed a search for latitudinal distribution patterns along the sandy coastal plains of Brazil using the non-metric multidimensional scaling method (NMDS) and the biotic element analysis to identify natural biogeographical units. The results showed a monotonic variation in anuran species composition along the latitudinal gradient with a break in the clinal pattern from 23°S to 25°S latitude (states of Rio de Janeiro to São Paulo). The major predictions of the vicariance model were corroborated by the detection of four biotic elements with significantly clustered distribution and by the presence of congeneric species distributed in distinct biotic elements. The results support the hypothesis that vicariance could be one of the factors responsible for the distribution patterns of the anuran communities along the sandy coastal plains of eastern Brazil. The results of the clusters are also congruent with the predictions of paleoclimatic models made for the Last Glacial Maximum of the Pleistocene, such as the presence of historical forest refugia and biogeographical patterns already detected for amphibians in the Atlantic Rainforest. PMID:26047484
Ariane Lima Xavier
Full Text Available The east coast of Brazil comprises an extensive area inserted in the Tropical Atlantic Domain and is represented by sandy plains of beach ridges commonly known as Restingas. The coastal environments are unique and house a rich amphibian fauna, the geographical distribution patterns of which are incipient. Biogeographical studies can explain the current distributional patterns and provide the identification of natural biogeographical units. These areas are important in elucidating the evolutionary history of the taxa and the areas where they occur. The aim of this study was to seek natural biogeographical units in the Brazilian sandy plains of beach ridges by means of distribution data of amphibians and to test the main predictions of the vicariance model to explain the patterns found. We revised and georeferenced data on the geographical distribution of 63 anuran species. We performed a search for latitudinal distribution patterns along the sandy coastal plains of Brazil using the non-metric multidimensional scaling method (NMDS and the biotic element analysis to identify natural biogeographical units. The results showed a monotonic variation in anuran species composition along the latitudinal gradient with a break in the clinal pattern from 23°S to 25°S latitude (states of Rio de Janeiro to São Paulo. The major predictions of the vicariance model were corroborated by the detection of four biotic elements with significantly clustered distribution and by the presence of congeneric species distributed in distinct biotic elements. The results support the hypothesis that vicariance could be one of the factors responsible for the distribution patterns of the anuran communities along the sandy coastal plains of eastern Brazil. The results of the clusters are also congruent with the predictions of paleoclimatic models made for the Last Glacial Maximum of the Pleistocene, such as the presence of historical forest refugia and biogeographical patterns already detected for amphibians in the Atlantic Rainforest.
Abad-Franch Fernando; Paucar C Aura; Carpio C Carlos; Cuba Cuba César A.; Aguilar V H Marcelo; Miles Michael A
Chagas disease control strategies strongly depend on the triatomine vector species involved in Trypanosoma cruzi transmission within each area. Here we report the results of the identification of specimens belonging to various species of Triatominae captured in Ecuador (15 species from 17 provinces) and deposited in the entomological collections of the Catholic University of Ecuador (Quito), Instituto Oswaldo Cruz (Brazil), the Natural History Museum London (UK), the London School of Hygiene ...
EDUARDO H. RAPOPORT
Full Text Available The percentage of exotic plant species (PES at large geographic scales is presented in form of political maps (Texas and North America and of isoline maps (Great Britain. In the latter case it is possible to visualize that higher proportions of alien invaders are present in urban and industrial areas as well as in maritime ports rather than in agricultural lands. Consequently, it is possible to predict that the ratio of urban to agricultural species will continue to increase in the future. Based on a survey of 200 world floras, a multiple regression analysis is presented in order to determine the importance of different factors in the yield of PES values. The contribution to the total variance was: disturbance degree 55 %; total species richness 14%; insularity 9%, and latitude 2%. Neither the mean annual precipitation nor the mean annual temperature showed a significant contribution to the total variance. The predominance of Europe as the main deliverer of weeds to other temperate regions in the world has been attributed to the aggressive or imperialistic geopolitics of this region, and to the construction of the first international oceanic fleet. There are reasons to believe, however, that the great size of Eurasia also played a role in the success of its weedy invasive flora. Since several authors found a weak positive correlation between the radial rate of dispersal and the invading success in plants, a table collecting 153 data allowed a first, tentative comparison among different taxa. The mean dispersal rates were 64.2 for microorganisms; 48.5 for invertebrates, 17.2 for vertebrates, 6.9 for plants, and 0.19 km/yr for palynological registers. A discussion about the significance of these results is included. An alternative way to compare invasive ability, especially among agricultural pests, is by means of an index of cosmopolitanism (C* which varied as follows: 0.642 for phytopathogens, 0.439 for insects and 0.259 for weeds. Weeds are 15 times, agricultural insects 26 times and phytopathogens 37 times more cosmopolitan than, say, common mammals, taken as an example for comparison. Finally, although animals (invertebrates plus vertebrates show a higher mean dispersal rate than plants (field observations plus ancient pollen registers, it seems that animals are better colonizers of pristine or scarcely disturbed communities, while plants are more successful in anthropic habitatsSe analiza el porcentaje de especies de plantas exóticas (PES a escala macrogeográfica en forma de mapas políticos (Texas y América del Norte y mapas de isolíneas (Gran Bretaña. En estos últimos se observa mayor concentración del PES en puertos y áreas urbanas e industriales más que en áreas agrícolas. En consecuencia, es predecible que la razón entre ruderales y arvenses siga aumentando en el futuro. Sobre la base de un censo de 200 floras del mundo se hace un análisis de regresión múltiple para determinar la importancia de factores que contribuyen a la variación en el PES (disturbios 55 %, riqueza de especies 14%, insularidad 9% y latitud 2%. Precipitación y temperatura media anual no contribuyen significativamente en la varianza. La predominancia de Europa como principal distribuidora mundial de malezas ha sido atribuida a su geopolítica imperialista y construcción de la primera flota marina internacional. A ello, sin embargo, debió contribuir también el tamaño de Eurasia. Ya que varios autores hallaron una débil correlación positiva entre la tasa de dispersión y el éxito invasor en plantas, se hizo una comparación entre taxones mediante 153 datos colectados. Las tasas lineales de dispersión, en km/año, fueron 64,2 en microorganismos, 48,5 en invertebrados, 17,2 en vertebrados, 6,9 en plantas y 0,19 en registros palinológicos. Otra manera de comparar la capacidad invasora, especialmente, en plagas agrícolas, es a través del índice de cosmopolitismo (C*, que resultó ser 0,642 para fitopatógenos, 0,439 para insectos y 0,259 para malezas. Las malezas son 15, los insectos agrícolas 26 veces y los fitopatógenos 37 veces más cosmopolitas que los mamíferos, tomados como ejemplo comparativo. Finalmente, aunque los animales (invertebrados y vertebrados muestran mayor tasa media de dispersión que las plantas, y son mejores colonizadores de comunidades prístinas o poco disturbadas, las plantas son más exitosas en ambientes antrópicos
Full Text Available Abstract Background Carassius auratus is a primary freshwater fish with bisexual diploid and unisexual gynogenetic triploid lineages. It is distributed widely in Eurasia and is especially common in East Asia. Although several genetic studies have been conducted on C. auratus, they have not provided clear phylogenetic and evolutionary descriptions of this fish, probably due to selection bias in sampling sites and the DNA regions analysed. As the first step in clarifying the evolutionary entity of the world's Carassius fishes, we attempted to clarify the phylogeny of C. auratus populations distributed in East Asia. Results We conducted a detailed analysis of a large dataset of mitochondrial gene sequences [CR, 323 bp, 672 sequences (528 sequenced + 144 downloaded; CR + ND4 + ND5 + cyt b, 4669 bp in total, 53 sequences] obtained from C. auratus in East Asia. Our phylogeographic analysis revealed two superlineages, one distributed mainly among the Japanese main islands and the other in various regions in and around the Eurasian continent, including the Ryukyus and Taiwan. The two superlineages include seven lineages with high regional specificity that are composed of endemic populations indigenous to each region. The divergence time of the seven lineages was estimated to be 0.2 million years ago (Mya by a fossil-based method and 1.0-1.9 Mya by the molecular clock method. The antiquity and endemism of these lineages suggest that they are native to their respective regions, although some seem to have been affected by the artificial introduction of C. auratus belonging to other lineages. Triploids of C. auratus did not form a monophyletic lineage but were clustered mostly with sympatric diploids. Conclusions The results of the present study revealed the existence of two superlineages of C. auratus in East Asia that include seven lineages endemic to each of the seven regions examined. The lack of substantial genetic separation between triploids and diploids indicates that triploids are not composed of a single independent lineage. The ancient origins and evolutionary uniqueness of the seven lineages warrant their conservation. An overall phylogenetic framework obtained from the present study will be of use for estimating the phylogenetic relationships of Carassius fishes on the Eurasian continent.
Ndiaye, A.; Ba, K.; Aniskin, V. M.; Benazzou, T.; Chevret, P.; Konečný, Adam; Sembene, M.; Tatard, C.; Kergoat, G. J.; Granjon, L.
Roč. 41, č. 1 (2012), s. 11-28. ISSN 0300-3256 R&D Projects: GA AV ČR IAA6093404 Institutional research plan: CEZ:AV0Z60930519 Keywords : geometric morphometrics * Middle Pleistocene * African gerbils * West Africa * taxonomy Subject RIV: EG - Zoology Impact factor: 2.793, year: 2012
Arias Fernández, María del Carmen
This paper examines the role played by palaeoceanographic and climatic conditions on the palaeobiogeography of the Pliensbachian–Toarcian ostracods (Early Jurassic) in the European Epicontinental Sea (EES). The influence of the palaeogeography, ocean currents and sea level, temperature and salinity variations on ostracod abundance, diversity and migration patterns is reconstructed. Ostracod migration follows an anticlockwise circulation in the eastern side of the EES, with a leading ...
National Oceanic and Atmospheric Administration, Department of Commerce — This dataset represents sediment size predictions from a sediment spatial model developed for the New York offshore spatial planning area. The model also includes...
Bartish, Igor; Antonelli, A.; Richardson, J. E.; Swenson, U.
Roč. 38, č. 1 (2011), s. 177-190. ISSN 0305-0270 Institutional research plan: CEZ:AV0Z60050516 Keywords : molecular dating * Neotropics * vicariance Subject RIV: EF - Botanics Impact factor: 4.544, year: 2011
Placostylus hongii (Lesson) is recorded from sites between Whangaroa and Whangarei on the mainland Northland coast, and from the Poor Knights, Chicken, Mokohinau and Great Barrier islands offshore. There is considerable variation in shell morphology between the various populations, commonly with marked morphological divergence at a local scale but with overlapping variation overall across all populations of the taxon. Patterns of morphological variation show no clear geographic trends and are at least in part related to local environmental factors. Correlations are identified between shell shape and substratum type, and between shell size and vegetation type. Placostylus hongii has a very restricted stratigraphic distribution in mainland Northland, with most if not all of the few known fossil populations post-dating Polynesian settlement at c. 900-700 years BP. We suggest that P. hongii populations on the Poor Knights and possibly also those on the Mokohinau islands are endemic, whereas the mainland populations and those on Great Barier and the Chicken islands have originated from anthropic redistribution of snails in prehistoric time. A high proportion of the mainland P. hongii populations and some offshore island populations became extinct in the last few hundred years as a result of predation by introduced mammals and the modification and destruction of shrubland and forest habitat. (author). 54 refs., 9 figs., 1 tab
Torres-Carvajal, Omar; Lobos, Simón E; Venegas, Pablo J; Chávez, Germán; Aguirre-Peñafiel, Vanessa; Zurita, Daniel; Echevarría, Lourdes Y
Nearly 50% of the diversity of the speciose Neotropical lizard clade Gymnophthalmidae is nested within the subclade Cercosaurinae. The taxonomy of Cercosaurinae lizards has been historically confusing because many diagnostic characters of those clades traditionally ranked as genera do not represent true diagnostic apomorphies. Even though molecular phylogenies of several 'genera' have been presented in the last few years, some of them remain poorly sampled (e.g., Anadia, Echinosaura, Potamites, Riama). In this paper we present a more comprehensive phylogeny of Cercosaurinae lizards with emphasis on Andean taxa from Ecuador and Peru, as well as a time-calibrated phylogeny with reconstruction of ancestral areas. Our analysis includes 52% of all recognized species of Cercosaurinae (67 species) and 1914 characters including three mitochondrial and one nuclear gene. We find that Anadia, Echinosaura, Euspondylus, Potamites, Proctoporus, and Riama are not monophyletic: the Tepuian Anadia mcdiarmidi is not sister to Andean species of Anadia; Echinosaura sulcarostrum is not included in the same clade formed by other species of Echinosaura and their more recent common ancestor; Teuchocercus is nested within Echinosaura; species of Euspondylus included in this study are nested within Proctoporus; Riama laudahnae is included in Proctoporus; and Potamites is paraphyletic and split in two separate clades, one of which we name Gelanesaurus, also a new genus-group name. Within Potamites, P. ecpleopus is paraphyletic, and P. strangulatus strangulatus and P. strangulatus trachodus are recognized as two distinct species. We also identify three unnamed clades (i.e., not nested within any of the recognized 'genera') from Andean populations in Ecuador and Peru. The estimated age of the clade Cercosaurinae (∼60Ma) corresponds to the early stages of the northern Andes. Even though the distribution of the most recent common ancestor of Cercosaurinae remains equivocal, our analysis shows that these lizards colonized and radiated along the northern Andes before reaching the central Andes in Peru. Finally, we present phylogenetic definitions for some of the recovered clades to promote a clear and precise classification of Cercosaurinae lizards. PMID:26975692
Previously, we documented a 14-fold increase in 3ADON-producing F. graminearum between 1998 and 2004 in western Canadian provinces. Significant population structure associated with trichothecene chemotype differences was observed, and isolates from the 3ADON populations were found to accumulate sig...
The primary goal of this research was to investigate the prokaryotic and fungal communities associated with the bulk soil, the rhizosphere, the phyllosphere, and the root and leaf endospheres, for three Agave species: the cultivated Agave tequilana and the native species, A. salmiana and A. deserti ...
Perry, G.; Rodda, G.H.; Fritts, T.H.; Sharp, T.R.
We sampled the lizard fauna of twenty-two small islets fringing the Pacific island of Guam and used these data to shed light on the processes responsible for present-day diversity. Habitat diversity, measured by islet area and vegetation complexity, was significantly correlated with the number of species found on an islet. However, islet distance and elevation were not significant predictors of diversity. Distribution patterns were slightly different for the two major families in our sample, Scincidae and Gekkonidae: skinks needed larger islets to maintain a population than did geckos. Presence/absence patterns were highly and significantly nested, and population density was correlated with the number of islets on which a species was found. An area cladogram was poorly supported and showed no faunal similarity between nearby islands. These patterns indicate that extinctions on most islets were due mostly to non-catastrophic, long-acting biological causes. The presence on the islets of species extirpated on Guam and the lack of significant nestedness on islands with greater maximum elevation highlight the impact that predators (primarily brown treesnakes) can have. Our findings also show that small reserves will not suffice to protect endangered lizard faunas, and that the islets may serve as a short-term repository of such species until snake-free areas can be established on Guam.
Strunecký, Otakar; Komárek, Jiří; Elster, Josef
Roč. 33, č. 4 (2012), 369-382. ISSN 0138-0338 R&D Projects: GA MŠk ME 934; GA MŠk LA341 Institutional research plan: CEZ:AV0Z60050516 Institutional support: RVO:67985939 Keywords : Svalbard * blue−green algae * ecology Subject RIV: EH - Ecology, Behaviour Impact factor: 0.745, year: 2012
Musilová, Zuzana; Říčan, O.; Říčanová, Š.; Janšta, P.; Gahura, O.; Novák, J.
Roč. 65, č. 3 (2015), s. 333-350. ISSN 1864-5755 R&D Projects: GA MŠk LC06073 Institutional support: RVO:67985904 Keywords : Andean uplift * Andinoacara * Mesoheros Subject RIV: EG - Zoology Impact factor: 0.593, year: 2014
Cronin, T. M.
Three types of geographic isolation - land barriers, deep water barriers, and climatic barriers - resulted in three distinct evolutionary responses in Neogene and Quaternary species of the epineritic ostracode genus Puriana. Through systematic, paleobiogeographic, and morphologic study of several hundred fossil and Recent populations from the eastern Pacific, western Atlantic, Gulf of Mexico, and the Caribbean, the phylogeny of the genus and the geography of speciation events were determined. Isolation of large populations by the Isthumus of Panama during the Pliocene did not lead to lineage splitting in species known to have existed before the Isthmus formed. Conversely, the establishment of small isolated populations on Caribbean islands by passive dispersal mechanisms frequently led to the evolution of new species or subspecies. Climatic changes along the southeastern United States during the Pliocene also catalyzed possible parapatric speciation as populations that immigrated to the northeastern periphery of the genus' range split to form new species. The results provide evidence that evolutionary models describing the influence of abiotic events on patterns of evolution and speciation can be tested using properly selected tectonic and climatic events and fossil groups amenable to species-level analysis. Two new species, P. bajaensis and P. paikensis, are described. -Author
Zajíc, Jaroslav; Štamberg, S.
Prague: Czech Geological Survey, 2013 - (Pašava, J.; Vymazalová, A.), s. 78-80 ISBN 978-80-7075-844-1 Institutional support: RVO:67985831 Keywords : palaeozoic * vertebrate Subject RIV: DB - Geology ; Mineralogy
Goüy de Bellocq, Joëlle; Leirs, H.; Bryja, Josef; Makundi, R.; Madebo, M.; Patzenhauerová, Hana; Šumbera, R.; Čížková, Dagmar; Mazoch, V.; Zima Jr., J.; Gryseels, S.; Akaibe, D.; Amundala, N.; Kennis, J.; Verheyen, E.; Laudisoit, A.; Schmidt-Chanasit, J.; Günther, S.
Kwaluseni: University of Swaziland, 2011. s. 79-80. [African Small Mammal Symposium /11./. 03.08.2011-08.08.2011, Kwaluseni] Institutional research plan: CEZ:AV0Z60930519 Keywords : arenaviruses * hantaviruses * Africa Subject RIV: EG - Zoology
Although theory dictates that limited gene flow between populations is a necessary precursor to speciation under allopatric and parapatric models, it is currently unclear how genetic differentiation between conspecific populations can arise in open-ocean plankton species. I examined two recently ...
Steadman, David W.; Oswald, Jessica A.; Rincón, Ascanio D.
The Neotropical lowlands sustain the world's richest bird communities, yet little that we know about their history is based on paleontology. Fossils afford a way to investigate distributional shifts in individual species, and thus improve our understanding of long-term change in Neotropical bird communities. We report a species-rich avian fossil sample from a late Pleistocene tar seep (Mene de Inciarte) in northwestern Venezuela. A mere 175 identified fossils from Mene de Inciarte represent 73 species of birds, among which six are extinct, and eight others no longer occur within 100 km. These 14 species consist mainly of ducks (Anatidae), snipe (Scolopacidae), vultures/condors (Vulturidae), hawks/eagles (Accipitridae), and blackbirds (Icteridae). Neotropical bird communities were richer in the late Pleistocene than today; their considerable extinction may be related to collapse of the large mammal fauna at that time. The species assemblage at Mene de Inciarte suggests that biogeographic patterns, even at continental scales, have been remarkably labile over short geological time frames. Mene de Inciarte is but one of 300 + tar seeps in Venezuela, only two of which have been explored for fossils. We may be on the cusp of an exciting new era of avian paleontology in the Neotropics.
Eder, Wolfgang; Kinoshita, Shunichi; Woeger, Julia; Hohenegger, Johann; Briguglio, Antonino; Ferrandez-Canadell, Carles
The foraminiferal subfamily Heterostegininae has been the centre of interest of many interdisciplinary studies in the last decades. Some of them reviewing only taxonomic criteria used to identify the different lineages by application of classical two dimensional biometry, while others focussing on more biological interests. This study tries to integrate new means of three-dimensional quantification on biometry used in micropalaeontology. By applying Micro-computed tomography (µCT) each chamber's volume of the foraminiferal test can be extracted and used to quantify and model the cell growth of larger benthic Foraminifera. This work concentrated on the single but abundant extant representative of the Heterostegina lineage (sensu d'Orbigny), H. depressa, studying the growth in specimens from two natural populations, Okinawa (Japan) and Maui (Hawaii), and from laboratory cultures (offspring of the Hawaiian population). Data obtained from measurements of the volume of the 25 initial chambers were fitted to a theoretical growth model using an exponential function. Two parameters of this function, a (= initial size) and b (= growth rate) were observed to reflect distinct information related to the either provenance or the ecology of the populations. The parameter a represents the proloculus size, which is frequently used in its two dimensional form (equatorial diameter) as a biometrical significant parameter. When comparing the proloculus volume in specimens of the three samples, a distinctive trend becomes visible: All specimens from a single locality group together, while laboratory cultured individuals are more similar to their relatives from Hawaii (with which they share the gene pool) than those from Okinawa. Proloculus volume is thus more influenced by internal (genetic) factors than to external (ecological) ones. Parameter b shows a different trend, related to the intensity of growth. The naturally grown specimens from different geographic localities show higher similarities in growth rates than those originating from the same gene pool. Therefore, growth rate seems to be more ecologically controlled than the proloculus volume, for instance by light intensity. More detailed investigation with larger samples from different geographical localities might allow to refine these observed patterns and to link them to the biogeographical distribution of this taxon.
Filipe, Ana F.; Araújo, Miguel B.; Doadrio, Ignacio; Angermeier, Paul L.; Collares-Pereira, Maria J.
Aim The question of how much of the shared geographical distribution of biota is due to environmental vs. historical constraints remains unanswered. The aim of this paper is to disentangle the contribution of historical vs. contemporary factors to the distribution of freshwater fish species. In addition, it illustrates how quantifying the contribution of each type of factor improves the classification of biogeographical provinces.
Licandro, P.; Blackett, M.; Fischer, A.; Hosia, A.; Kennedy, J.; Kirby, R. R.; Raab, K.; Stern, R.; Tranter, P.
Scientific debate on whether or not the recent increase in reports of jellyfish outbreaks represents a true rise in their abundance has outlined a lack of reliable records of Cnidaria and Ctenophora. Here we describe different jellyfish data sets produced within the EU programme EURO-BASIN. These data were assembled with the aim of creating an improved baseline and providing new data that can be used to evaluate the current diversity and standing stocks of jellyfish in the North Atlantic region. Using a net adapted to sample gelatinous zooplankton quantitatively, cnidarians and ctenophores were collected from the epipelagic layer during spring-summer 2010-2013, in inshore and offshore waters between lat 59 and 68° N and long 62° W and 5° E. Jellyfish were also identified and counted in samples opportunistically collected by other sampling equipment in the same region and at two coastal stations in the Bay of Biscay and in the Gulf of Cadiz. Continuous Plankton Recorder (CPR) samples collected in 2009-2012 were re-analysed with the aim of identifying the time and location of cnidarian blooms across the North Atlantic Basin. Overall the data show high variability in jellyfish abundance and diversity, mainly in relation to different water masses and bathymetry. Higher densities were generally recorded on the shelves, where the communities tend to be more diverse due to the presence of meropelagic medusae. Comparison of net records from the G.O. Sars transatlantic cruise shows that information on jellyfish diversity differs significantly depending on the sampling gear utilised. Indeed, the big trawls mostly collect relatively large scyphozoan and hydrozoan species, while small hydrozoans and early stages of Ctenophora are only caught by smaller nets. Based on CPR data from 2009 to 2012, blooms of cnidarians occurred in all seasons across the whole North Atlantic Basin. Molecular analysis revealed that, contrary to previous hypotheses, the CPR is able to detect blooms of meroplanktonic and holoplanktonic hydrozoans and scyphozoans. Through combination of different types of data, key jellyfish taxa for the spring-summer period were identified in the northern North Atlantic regions. Key species for the central and southern North Atlantic could be inferred based on the blooms identified by the CPR survey, although this should be confirmed further by comparison with quantitative data. The identification by DNA barcoding of 23 jellyfish specimens collected during the EURO-BASIN cruises contributes to increasing the still very limited number of jellyfish sequences available on GenBank. All observations presented here can be downloaded from PANGAEA (http://doi.pangaea.de/10.1594/PANGAEA.835732).
Moniliophthora roreri is the causal agent of frosty pod rot, which occurs on the neotropical rainforest genera Theobroma and Herrania. While this basidiomycete has had devastating effects on the commercially important cacao tree (T. cacao) in tropical America, where it is confined, little is known ...
Bryja, Josef; Patzenhauerová, Hana; Mikula, Ondřej; Matur, Ferhat; Chitaukali, W. N.; Verheyen, E.; Šumbera, R.
Paris: Université P. et M. Curie, 2011. s. 69 [European Congress of Mammalogy /7./. 19.07.2011-23.07.2011, Paris] Institutional research plan: CEZ:AV0Z60930519 Keywords : forest-dwelling mountain rodent * Eastern Africa Subject RIV: EG - Zoology http://www.alphavisa.com/ecm2011/pdf/ECM2011-Abstract_Book.pdf
Aquatic invasive species are one of the major ecological threats to the ecological integrity of estuarine and near-coastal waters. However, lack of systematic inventories of nonindigenous species across the North Pacific countries limits our ability to assess how the extent of i...
Melle, W.; Runge, J. A.; Head, E.; Plourde, S.; Castellani, C.; Licandro, P.; Pierson, J.; Jónasdóttir, S. H.; Johnson, C.; Broms, C.; Debes, H.; Falkenhaug, T.; Gaard, E.; Gislason, A.; Heath, M. R.; Niehoff, B.; Nielsen, T. G.; Pepin, P.; Stenevik, E. K.; Chust, G.
Here we present a new, pan-North-Atlantic compilation of data on key mesozooplankton species, including the most important copepod, Calanus finmarchicus. Distributional data of eight representative zooplankton taxa, from recent (2000-2009) Continuous Plankton Recorder data, are presented, along with basin-scale data of the phytoplankton colour index. Then we present a compilation of data on C. finmarchicus, including observations of abundance, demography, egg production and female size, with accompanying data on temperature and chlorophyll. This is a contribution by Canadian, European and US scientists and their institutions: http://doi.pangaea.de/10.1594/PANGAEA.820732, http://doi.pangaea.de/10.1594/PANGAEA.824423, http://doi.pangaea.de/10.1594/PANGAEA.828393 (please also see Melle et al., 2013; Castellani and Licandro, 2013; Jónasdóttir et al., 2014).
Brandt, A.; Brix, S.; Brökeland, W.; Cedhagen, Tomas; Choudhury, M.; Cornelius, N.; Danis, B.; De Mesel, I.; Diaz, R.J.; Gillan, D.C.; Ebbe, B.; Howe, J.; Janussen, D.; Kaiser, S.; Linse, K.; Malyutina, M.; Brandao, S.N.; Pawlowski, J.; Raupach, M.; Vanreuse, A.; Gooday, A.J.
Shallow marine benthic communities around Antarctica show high levels of endemism, gigantism, slow growth, longevity and late maturity, as well as adaptive radiations that have generated considerable biodiversity in some taxa1. The deeper parts of the Southern Ocean exhibit some unique environmen...
Southern South America and Australia/New Zealand share some 15 plant families more or less restricted to them. Understanding these Austral floristic links requires extensive sampling in both regions. For the Alstroemeriaceae, with 189 species in three South American genera, two in an Australian/Tasm...
Brischoux, François; Cotté, Cédric; Lillywhite, Harvey B; Bailleul, Frédéric; Lalire, Maxime; Gaspar, Philippe
It is well recognized that most marine vertebrates, and especially tetrapods, precisely orient and actively move in apparently homogeneous oceanic environments. Here, we investigate the presumptive role of oceanic currents in biogeographic patterns observed in a secondarily marine tetrapod, the yellow-bellied sea snake (Hydrophis [Pelamis] platurus). State-of-the-art world ocean circulation models show how H. platurus, the only pelagic species of sea snake, can potentially exploit oceanic currents to disperse and maintain population mixing between localities that spread over two-thirds of the Earth's circumference. The very close association of these snakes with surface currents seems to provide a highly efficient dispersal mechanism that allowed this species to range extensively and relatively quickly well beyond the central Indo-Pacific area, the centre of origin, abundance and diversity of sea snakes. Our results further suggest that the pan-oceanic population of this species must be extraordinarily large. PMID:27555651
Mittelasien (Kasachstan, Kirgistan, Tadschikistan, Turkmenistan, Usbekistan) ist neben dem Mediterranraum das bedeutendste paläarkische Bienen-Diversitätszentrum (MICHENER 1979). POPOV (1957) schätzt für den Raum 1.200 Arten aus 70 Gattungen, die Gesamtzahl dürfte jedoch bei über 2.000 Arten liegen. Über die innere biogeographische Gliederung der Region und die Lage von Endemiezentren ist bei den Bienen jedoch kaum etwas bekannt (POPOV 1958, MARIKOVSKAYA 1999). Am Beispiel der Seidenbienengat...
Sims, C. A.; Riginos, C.; Blomberg, S. P.; Huelsken, T.; Drew, J.; Grutter, A. S.
Cleaner fishes are some of the most conspicuous organisms on coral reefs due to their behaviour and prominent body pattern, consisting of a lateral stripe and blue/yellow colouration. All obligate cleaner fishes share this body stripe pattern, which is an important signal for attracting client fishes. However, variability in the cleaning signal of the cleaner fish Labroides dimidiatus has been documented across its range. Here, we investigate the geographic distribution of cleaner signal polymorphisms in L. dimidiatus and contrast this to phylogeographic variation in mitochondrial (mt) DNA. We used samples from 12 sites for genetic analyses, encompassing much of L. dimidiatus' range from the Red Sea to Fiji. We obtained morphometric measures of the cleaner signal body stripe width from individuals among six of the sites and qualitatively grouped tail stripe shape. mtDNA control region sequences were used for phylogenetic and population genetic analyses. We found that body stripe width was significantly correlated with tail stripe shape and geographical location, with Indian Ocean populations differing in morphology from western Pacific populations. L. dimidiatus haplotypes formed two reciprocally monophyletic clades, although in contrast to morphology, Japanese cleaner fish fell within the same clade as Indian Ocean cleaner fish and both clade types were sympatric in Papua New Guinea. An additional novel finding of our research was that the inclusion of two closely related cleaner fish species, Labroides pectoralis and Labroides bicolor, in the phylogenetic analysis rendered L. dimidiatus polyphyletic. Overall, the findings suggest the diversity within L. dimidiatus is underestimated.
Pozio, Edoardo; Hoberg, Eric; La Rosa, Giuseppe; Zarlenga, Dante S
Studying parasites of the genus Trichinella provides scientists of today many advantages. This is a group of zoonotic nematodes that circulates freely among wildlife hosts with one in particular, Trichinella spiralis that is exceptionally well adapted to domestic swine. Recent reports suggest that human infections from hunted animals are on the rise worldwide and numerous countries still experience problems with T. spiralis in their domestic food supplies. Trichinella is a genus whose members are easily propagated in the laboratories, have been used as models to investigate host-parasite relationships and parasitism among clade I organisms, and represent a poorly investigated link between the phylum Nematoda and other Metazoans. The importance of T. spiralis in better understanding the tree of life was so recognized that in 2004, its genome was carefully selected as one of only nine key non-mammalian organisms to be sequenced to completion. Since it was first discovered in 1835, this genus has expanded from being monospecific to eight species including four other genotypes of undetermined taxonomic rank. Inasmuch as discriminating morphological data have been scant, our understanding of the genus has been relegated to a compilation of molecular, biochemical and biological data. Herein, we provide a collection of information and up-to-date interpretations on the taxonomy, diagnostics, systematics, micro- and macroevolution, and the biogeographical and biohistorical reconstruction of the genus Trichinella. PMID:19460327
Das, Ranajit; Hergenrother, Scott D; Soto-Calderón, Iván D; Dew, J Larry; Anthony, Nicola M; Jensen-Seaman, Michael I
The Western and Eastern species of gorillas (Gorilla gorilla and Gorilla beringei) began diverging in the mid-Pleistocene, but in a complex pattern with ongoing gene flow following their initial split. We sequenced the complete mitochondrial genomes of 1 Eastern and 1 Western gorilla to provide the most accurate date for their mitochondrial divergence, and to analyze patterns of nucleotide substitutions. The most recent common ancestor of these genomes existed about 1.9 million years ago, slightly more recent than that of chimpanzee and bonobo. We in turn use this date as a calibration to reanalyze sequences from the Eastern lowland and mountain gorilla subspecies to estimate their mitochondrial divergence at approximately 380000 years ago. These dates help frame a hypothesis whereby populations became isolated nearly 2 million years ago with restricted maternal gene flow, followed by ongoing male migration until the recent past. This process of divergence with prolonged hybridization occurred against the backdrop of the African Pleistocene, characterized by intense fluctuations in temperature and aridity, while at the same time experiencing tectonic uplifting and consequent shifts in the drainage of major river systems. Interestingly, this same pattern of introgression following divergence and discrepancies between mitochondrial and nuclear loci is seen in fossil hominins from Eurasia, suggesting that such processes may be common in hominids and that living gorillas may provide a useful model for understanding isolation and migration in our extinct relatives. PMID:25189777
Das, Ranajit; Hergenrother, Scott D.; Soto-Calderón, Iván D.; Dew, J. Larry; Anthony, Nicola M; Jensen-Seaman, Michael I
The Western and Eastern species of gorillas (Gorilla gorilla and Gorilla beringei) began diverging in the mid-Pleistocene, but in a complex pattern with ongoing gene flow following their initial split. We sequenced the complete mitochondrial genomes of 1 Eastern and 1 Western gorilla to provide the most accurate date for their mitochondrial divergence, and to analyze patterns of nucleotide substitutions. The most recent common ancestor of these genomes existed about 1.9 million years ago, sli...
Lawton, R. O.; Nair, U. S.; Ray, D.; Regmi, A.; Pounds, J. A.; Welch, R. M.
Sites described as tropical montane cloud forests differ greatly, in part because observers tend to differ in their opinion as to what constitutes frequent and prolonged immersion in cloud. This definitional difficulty interferes with hydrologic analyses, assessments of environmental impacts on ecosystems, and biogeographical analyses of cloud forest communities and species. Quantitative measurements of cloud immersion can be obtained on site, but the observations are necessarily spatially limited, although well-placed observers can examine 10 50 km of a mountain range under rainless conditions. Regional analyses, however, require observations at a broader scale. This chapter discusses remote sensing and modeling approaches that can provide quantitative measures of the spatiotemporal patterns of cloud cover and cloud immersion in tropical mountain ranges. These approaches integrate remote sensing tools of various spatial resolutions and frequencies of observation, digital elevation models, regional atmospheric models, and ground-based observations to provide measures of cloud cover, cloud base height, and the intersection of cloud and terrain. This combined approach was applied to the Monteverde region of northern Costa Rica to illustrate how the proportion of time the forest is immersed in cloud may vary spatially and temporally. The observed spatial variation was largely due to patterns of airflow over the mountains. The temporal variation reflected the diurnal rise and fall of the orographic cloud base, which was influenced in turn by synoptic weather conditions, the seasonal movement of the Intertropical Convergence Zone and the north-easterly trade winds. Knowledge of the proportion of the time that sites are immersed in clouds should facilitate ecological comparisons and biogeographical analyses, as well as land use planning and hydrologic assessments in areas where intensive on-site work is not feasible.
Full Text Available Deep-sea hydrothermal vent fields are areas on the seafloor with high biological productivity fueled by microbial chemosynthesis. Members of the Aquificales genus Persephonella are obligately chemosynthetic bacteria, and appear to be key players in carbon, sulfur, and nitrogen cycles in high temperature habitats at deep-sea vents. Although this group of bacteria has cosmopolitan distribution in deep-sea hydrothermal ecosystem around the world, little is known about their population structure such as intraspecific genomic diversity, distribution pattern, and phenotypic diversity. We developed the multi-locus sequence analysis (MLSA scheme for their genomic characterization. Sequence variation was determined in five housekeeping genes and one functional gene of 36 P. hydrogeniphila strains originated from the Okinawa Trough and the South Mariana Trough. Although the strains share > 98.7% similarities in 16S rRNA gene sequences, MLSA revealed 35 different sequence types, indicating their extensive genomic diversity. A phylogenetic tree inferred from all concatenated gene sequences revealed the clustering of isolates according to the geographic origin. In addition, the phenotypic clustering pattern inferred from whole-cell matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF/MS analysis can be correlated to their MLSA clustering pattern. This study represents the first MLSA combined with phenotypic analysis indicative of allopatric speciation of deep-sea hydrothermal vent bacteria.
Full Text Available Massive usage, along with careless handling, storage, spills and leakages made chloroethenes (CEs one of the most abundant classes of groundwater contaminants. Anaerobic organohalide-respiring bacteria (OHRB can couple reductive dechlorination of CEs with energy conservation, a central microbial process in (enhanced natural attenuation of CE-contaminated aquifers. Spatial variability of OHRB guild members present in contaminated sites has not yet been investigated in detail and it is not known whether the spatial localization of contaminated sites could impact differentially remediation capacities. The goal of this study was to investigate how spatially-distant microbial communities responded to the presence of CEs. Bacterial communities associated with five geographically distant European CEs-contaminated aquifers were analyzed with terminal-restriction fragment length polymorphism. Numerical ecology tools were used to assess the separate and combined effects on the communities of their spatial localization, their local environmental conditions and their contaminant concentrations. Three spatial scales were used for the assessment of the structuration of the communities as a function of geographical distances, namely at the aquifer scale, at medium (50 km and long (ca. 1000 km distances between aquifers. As a result, bacterial communities were structured with an almost identical contribution by both the geographical position of the aquifer and local environmental variables, especially electron donors and acceptors. The impact of environmental factors decreased with distance between aquifers, with the concomitant increase in importance of a geographical factor. Contrastingly, CEs contributed at a low extent at the medium scale and became important only when all aquifers were considered together, at a large geographical scale, suggesting that distant communities were structured partially by a common niche specialization in organohalide respiration.
Pietro L H de Mello
Full Text Available Little is known about the threat levels and impacts of habitat loss over the Cerrado Squamate fauna. The region is under severe habitat loss due to mechanized agriculture, accelerated by changes in the Brazilian National Forest Code. The Squamate fauna of the Cerrado is rich in endemics and is intrinsically associated with its surrounding microhabitats, which make up a mosaic of phitophysiognomies throughout the region. Herein we evaluate current conservation status of Squamate biogeographic patterns in the Brazilian Cerrado, the single savanna among global biodiversity hotspots. To do so, we first updated point locality data on 49 endemic Squamates pertaining to seven non-random clusters of species ranges in the Cerrado. Each cluster was assumed to be representative of different biogeographic regions, holding its own set of species, herein mapped according to their extent of occurrence (EOO. We then contrasted these data in four different scenarios, according to the presence or absence of habitat loss and the presence or absence of the current protected area (PA cover. We searched for non-random patterns of habitat loss and PA coverage among these biogeographic regions throughout the Cerrado. Finally, with the species EOO as biodiversity layers, we used Zonation to discuss contemporary PA distribution, as well as to highlight current priority areas for conservation within the Cerrado. We ran Zonation under all four conservation scenarios mentioned above. We observed that habitat loss and PA coverage significantly differed between biogeographic regions. The southernmost biogeographic region is the least protected and the most impacted, with priority areas highly scattered in small, disjunct fragments. The northernmost biogeographic region (Tocantins-Serra Geral is the most protected and least impacted, showing extensive priority areas in all Zonation scenarios. Therefore, current and past deforestation trends are severely threatening biogeographic patterns in the Cerrado. Moreover, PA distribution is spatially biased, and does not represent biogeographic divisions of the Cerrado. Consequently, we show that biogeographic patterns and processes are being erased at an accelerated pace, reinforcing the urgent need to create new reserves and to avoid the loss of the last remaining fragments of once continuous biogeographic regions. These actions are fundamental and urgent for conserving biogeographic and evolutionary information in this highly imperiled savanna hotspot.
de Mello, Pietro L H; Machado, Ricardo B; Nogueira, Cristiano de C
Little is known about the threat levels and impacts of habitat loss over the Cerrado Squamate fauna. The region is under severe habitat loss due to mechanized agriculture, accelerated by changes in the Brazilian National Forest Code. The Squamate fauna of the Cerrado is rich in endemics and is intrinsically associated with its surrounding microhabitats, which make up a mosaic of phitophysiognomies throughout the region. Herein we evaluate current conservation status of Squamate biogeographic patterns in the Brazilian Cerrado, the single savanna among global biodiversity hotspots. To do so, we first updated point locality data on 49 endemic Squamates pertaining to seven non-random clusters of species ranges in the Cerrado. Each cluster was assumed to be representative of different biogeographic regions, holding its own set of species, herein mapped according to their extent of occurrence (EOO). We then contrasted these data in four different scenarios, according to the presence or absence of habitat loss and the presence or absence of the current protected area (PA) cover. We searched for non-random patterns of habitat loss and PA coverage among these biogeographic regions throughout the Cerrado. Finally, with the species EOO as biodiversity layers, we used Zonation to discuss contemporary PA distribution, as well as to highlight current priority areas for conservation within the Cerrado. We ran Zonation under all four conservation scenarios mentioned above. We observed that habitat loss and PA coverage significantly differed between biogeographic regions. The southernmost biogeographic region is the least protected and the most impacted, with priority areas highly scattered in small, disjunct fragments. The northernmost biogeographic region (Tocantins-Serra Geral) is the most protected and least impacted, showing extensive priority areas in all Zonation scenarios. Therefore, current and past deforestation trends are severely threatening biogeographic patterns in the Cerrado. Moreover, PA distribution is spatially biased, and does not represent biogeographic divisions of the Cerrado. Consequently, we show that biogeographic patterns and processes are being erased at an accelerated pace, reinforcing the urgent need to create new reserves and to avoid the loss of the last remaining fragments of once continuous biogeographic regions. These actions are fundamental and urgent for conserving biogeographic and evolutionary information in this highly imperiled savanna hotspot. PMID:26252746
Full Text Available Subsocial, xylophagous cockroaches of the genus Cryptocercus exhibit a disjunct distribution, with representatives in mature montane forests of North America, China, Korea and the Russian Far East. All described species are wingless and dependent on rotting wood for food and shelter at all stages of their life cycle; consequently, their distribution is tied to that of forests and strongly influenced by palaeogeographical events. Asian and American lineages form distinct monophyletic groups, comprised of populations with complex geographic substructuring. We review the phylogeny and distribution of Cryptocercus, and discuss splitting events inferred from molecular data.
Lutz, Holly L; Weckstein, Jason D; Patané, José S L; Bates, John M; Aleixo, Alexandre
Andean uplift, Plio-Pleistocene climatic fluctuation, and river dynamics in the Amazon basin have all been implicated in the diversification of the South American avifauna. We reconstructed phylogenetic relationships in the genus Selenidera, which has served as a classic case of putative refugial speciation, and the closely related genus Andigena, to better understand the processes driving their diversification. Using mitochondrial and nuclear DNA sequences, we constructed a phylogeny to estimate the pattern and timing of divergence within and between seven lowland Selenidera toucanets and the five species of Andigena mountain-toucans, which together form a single clade. All phylogenetic analyses supported the monophyly of the montane genus Andigena, but indicated that the genus Selenidera is likely paraphyletic with respect to Andigena. Our time tree analysis is consistent with the orogenic uplift of the northern Andean range having initiated the divergence between Selenidera and Andigena, and that the movement and fragmentation of montane habitats in response to Pleistocene climatic oscillations likely influenced diversification within Andigena. Estimated divergence times for lowland Amazonian Selenidera did not support the Last Glacial Maximum (LGM) refuge hypothesis as an important biogeographic factor for the diversification of lineages studied here. The timing of divergence within Selenidera is consistent with the hypothesis that geographic isolation of areas of endemism generated by Amazonian river dynamics during the Plio-Pleistocene contributed to Selenidera speciation and current species distributions. PMID:23831458
Chatterjee, Sankar; Scotese, Christopher
Palaeobiogeographic analysis of Indian tetrapods during the Late Cretaceous-Early Tertiary time has recognized that both vicariance and geodispersal have played important roles in producing biogeographic congruence. The biogeographic patterns show oscillating cycles of geodispersal (Late Cretaceous), followed by congruent episodes of vicariance and geodispersal (Early Eocene), followed by another geodispersal event (Middle Eocene). New biogeographic synthesis suggests that the Late Cretaceous Indian tetrapod fauna is cosmopolitan with both Gondwanan and Laurasian elements. Throughout most of the Cretaceous, India was separated from the rest of Gondwana, but in the latest Cretaceous it reestablished contact with Africa through Kohistan-Dras (K-D) volcanic arc, and maintained biotic link with South America via Ninetyeast Ridge-Kerguelen-Antarctica corridor. These two geodispersal routes allowed exchanges of "pan-Gondwana" terrestrial tetrapods from Africa, South America, and Madagascar. During that time India also maintained biotic connections with Laurasia across the Neotethys via Kohistan-Dras Arc and Africa. During the Palaeocene, India, welded to the K-D Arc, rafted like a "Noah's Ark" as an island continent and underwent rapid cladogenesis because of allopatric speciation. Although the Palaeocene fossil record is blank, Early Eocene tetrapods contain both endemic and cosmopolitan elements, but Middle Eocene faunas have strong Asian character. India collided with Asia in Early and Middle Eocene time and established a new northeast corridor for faunal migration to facilitate the bidirectional "Great Asian Interchange" dispersals.
Hodač, Ladislav; Hallmann, Christine; Spitzer, Karolin; Elster, Josef; Faßhauer, Fabian; Brinkmann, Nicole; Lepka, Daniela; Diwan, Vaibhav; Friedl, Thomas
Chlorella and Stichococcus are morphologically simple airborne microalgae, omnipresent in terrestrial and aquatic habitats. The minute cell size and resistance against environmental stress facilitate their long-distance dispersal. However, the actual distribution of Chlorella- and Stichococcus-like species has so far been inferred only from ambiguous morphology-based evidence. Here we contribute a phylogenetic analysis of an expanded SSU and ITS2 rDNA sequence dataset representing Chlorella- and Stichococcus-like species from terrestrial habitats of polar, temperate and tropical regions. We aim to uncover biogeographical patterns at low taxonomic levels. We found that psychrotolerant strains of Chlorella and Stichococcus are closely related with strains originating from the temperate zone. Species closely related to Chlorella vulgaris and Muriella terrestris, and recovered from extreme terrestrial environments of polar regions and hot deserts, are particularly widespread. Stichococcus strains from the temperate zone, with their closest relatives in the tropics, differ from strains with the closest relatives being from the polar regions. Our data suggest that terrestrial Chlorella and Stichococcus might be capable of intercontinental dispersal; however, their actual distributions exhibit biogeographical patterns. PMID:27279416
SayakaMino; HirokoMaikita; TomohiroToki; ShingoKato; HiromiWatanabe; ShigeakiKojima
Deep-sea hydrothermal vent fields are areas on the seafloor with high biological productivity fueled by microbial chemosynthesis. Members of the Aquificales genus Persephonella are obligately chemosynthetic bacteria, and appear to be key players in carbon, sulfur, and nitrogen cycles in high temperature habitats at deep-sea vents. Although this group of bacteria has cosmopolitan distribution in deep-sea hydrothermal ecosystem around the world, little is known about their population structure ...
Mino, Sayaka; Makita, Hiroko; Toki, Tomohiro; Miyazaki, Junichi; Kato, Shingo; Watanabe, Hiromi; Imachi, Hiroyuki; Watsuji, Tomo-O; Nunoura, Takuro; Kojima, Shigeaki; Sawabe, Tomoo; Takai, Ken; Nakagawa, Satoshi
Deep-sea hydrothermal vent fields are areas on the seafloor with high biological productivity fueled by microbial chemosynthesis. Members of the Aquificales genus Persephonella are obligately chemosynthetic bacteria, and appear to be key players in carbon, sulfur, and nitrogen cycles in high temperature habitats at deep-sea vents. Although this group of bacteria has cosmopolitan distribution in deep-sea hydrothermal ecosystem around the world, little is known about their population structure such as intraspecific genomic diversity, distribution pattern, and phenotypic diversity. We developed the multi-locus sequence analysis (MLSA) scheme for their genomic characterization. Sequence variation was determined in five housekeeping genes and one functional gene of 36 Persephonella hydrogeniphila strains originated from the Okinawa Trough and the South Mariana Trough (SNT). Although the strains share >98.7% similarities in 16S rRNA gene sequences, MLSA revealed 35 different sequence types (ST), indicating their extensive genomic diversity. A phylogenetic tree inferred from all concatenated gene sequences revealed the clustering of isolates according to the geographic origin. In addition, the phenotypic clustering pattern inferred from whole-cell matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF/MS) analysis can be correlated to their MLSA clustering pattern. This study represents the first MLSA combined with phenotypic analysis indicative of allopatric speciation of deep-sea hydrothermal vent bacteria. PMID:23630523
Mino, Sayaka; Makita, Hiroko; Toki, Tomohiro; Miyazaki, Junichi; Kato, Shingo; Watanabe, Hiromi; Imachi, Hiroyuki; Watsuji, Tomo-o; Nunoura, Takuro; Kojima, Shigeaki; Sawabe, Tomoo; Takai, Ken; Nakagawa, Satoshi
Deep-sea hydrothermal vent fields are areas on the seafloor with high biological productivity fueled by microbial chemosynthesis. Members of the Aquificales genus Persephonella are obligately chemosynthetic bacteria, and appear to be key players in carbon, sulfur, and nitrogen cycles in high temperature habitats at deep-sea vents. Although this group of bacteria has cosmopolitan distribution in deep-sea hydrothermal ecosystem around the world, little is known about their population structure ...
Romero-Pérez, Gustavo A.; Ominski, Kim H.; McAllister, Tim A.; Denis O Krause
Feces from cattle production are considered important sources of bacterial contamination of food and the environment. Little is known about the combined effects of arctic temperatures and fodder tannins on rumen and hindgut bacterial populations. Individual rumen liquor and rectal fecal samples from donor steers fed either alfalfa silage or sainfoin (Onobrychis viciifolia Scop.) silage and water ad libitum were collected weekly on the first three sampling days and fortnightly afterwards. The ...
Galván-Quesada, Sesángari; Doadrio, Ignacio; Alda, Fernando; Perdices, Anabel; Reina, Ruth Gisela; García Varela, Martín; Hernández, Natividad; Campos Mendoza, Antonio; Bermingham, Eldredge; Domínguez-Domínguez, Omar
Species of the genus Dormitator, also known as sleepers, are representatives of the amphidromous freshwater fish fauna that inhabit the tropical and subtropical coastal environments of the Americas and Western Africa. Because of the distribution of this genus, it could be hypothesized that the evolutionary patterns in this genus, including a pair of geminate species across the Central American Isthmus, could be explained by vicariance following the break-up of Gondwana. However, the evolutionary history of this group has not been evaluated. We constructed a time-scaled molecular phylogeny of Dormitator using mitochondrial (Cytochrome b) and nuclear (Rhodopsin and β-actin) DNA sequence data to infer and date the cladogenetic events that drove the diversification of the genus and to relate them to the biogeographical history of Central America. Two divergent lineages of Dormitator were recovered: one that included all of the Pacific samples and another that included all of the eastern and western Atlantic samples. In contrast to the Pacific lineage, which showed no phylogeographic structure, the Atlantic lineage was geographically structured into four clades: Cameroon, Gulf of Mexico, West Cuba and Caribbean, showing evidence of potential cryptic species. The separation of the Pacific and Atlantic lineages was estimated to have occurred ~1 million years ago (Mya), whereas the four Atlantic clades showed mean times of divergence between 0.2 and 0.4 Mya. The splitting times of Dormitator between ocean basins are similar to those estimated for other geminate species pairs with shoreline estuarine preferences, which may indicate that the common evolutionary histories of the different clades are the result of isolation events associated with the closure of the Central American Isthmus and the subsequent climatic and oceanographic changes. PMID:27074006
National Oceanic and Atmospheric Administration, Department of Commerce — This dataset represents depth uncertainty predictions from a bathymetric model developed for the New York offshore spatial planning area. The model also includes...
Juan J. Morrone
Full Text Available El reconocimiento de componentes bióticos constituye una primera etapa hacia una teoría biogeográfica sintética. En México podemos caracterizar 3 componentes bióticos principales, cada uno con una combinación diferente de elementos bióticos. El componente Neártico (región Neártica incluye las áreas áridas subtropicales del norte del país, en las provincias biogeográficas de California, Baja California, Sonora, Altiplano Mexicano y Tamaulipas. En este componente predomina el elemento original (Septentrional Antiguo o Paleoamericano, junto con otro de dispersión más reciente (Neártico y un tercero Neotropical Antiguo. Los eventos vicariantes asociados con la evolución biótica del componente Neártico se relacionan con la formación de la Sierra Madre Occidental, que aisló el desierto de Chihuahua de los desiertos de Sonora y Mohave; y la expansión del Mar de Cortés, que aisló la Península de Baja California del continente. El componente Transicional (Zona de Transición Mexicana incluye las áreas básicamente montañosas del centro del país, que se asignan a las provincias biogeográficas de la Sierra Madre Oriental, Sierra Madre Occidental, Eje Volcánico Transmexicano, Cuenca del Balsas y Sierra Madre del Sur. En este componente coexisten los elementos Paleoamericano, Neártico, Mesoamericano Tropical y Mesoamericano de Montaña. Los eventos vicariantes asociados con la evolución biótica del componente Transicional se relacionan con el desarrollo de las Sierras Madre y el vulcanismo del Eje Volcánico Transmexicano. El componente Neotropical (región Neotropical incluye áreas tropicales húmedas y subhúmedas del sur de México, asignadas a las provincias biogeográficas de la Costa Pacífica Mexicana, Golfo de México, Chiapas y Península de Yucatán. En éste predomina el elemento Mesoamericano Tropical, aunque también presenta los elementos Neártico y Antillano. Los eventos vicariantes asociados con la evolución biótica del componente Neotropical se relacionan con el desarrollo de los istmos de Tehuantepec y Panamá y la inundación de las tierras bajas de Nicaragua y de la Península de Yucatán.Recognition of biotic components constitutes the first step toward a synthetic biogeographic theory. In Mexico we can characterize three main biotic components, each one having a particular combination of different biotic elements. The Nearctic component (Nearctic region includes the arid subtropical areas in the north of the country, in the Californian, Baja Californian, Sonoran, Mexican Plateau and Tamaulipan biogeographic provinces. This component is dominated by the original element (Old Northern or Paleoamerican, together with one of more recent dispersal (Nearctic and a third of ancient Neotropical origin. Vicariant events associated with the biotic evolution of the Nearctic component are related to the uplift of the Sierra Madre Occidental, which separated the Chihuahuan desert from the Sonoran and Mojave deserts; and the expansion of the Sea of Cortes, separating the Peninsula of Baja California from the continental mainland. The Transitional component (Mexican Transition Zone includes basically montane areas in central Mexico, which are assigned to the Sierra Madre Oriental, Sierra Madre Occidental, Transmexican Volcanic Belt, Balsas basin and Sierra Madre del Sur biogeographic provinces. In this component, the Paleoamerican, Nearctic, Tropical Mesoamerican and Montane Mesoamerican elements coexist. Vicariant events associated with the biotic evolution of the Transitional component are the development of the Sierras Madre and the volcanism of the Transmexican Volcanic Belt. The Neotropical component (Neotropical region includes humid and subhumid tropical areas of southern Mexico, assigned to the Mexican Pacific Coast, Mexican Gulf, Chiapas and Yucatan Peninsula biogeographic provinces. In it the Tropical Mesoamerican element predominates, but Nearctic and Antillean elements are also present. Vicariant events associated with the biotic evolution of the Neotropical component are related to the development of the isthmuses of Tehuantepec and Panama, and the inundation of the lowlands of Nicaragua and the Yucatan Peninsula.
Jeffries, Thomas C; Ostrowski, Martin; Williams, Rohan B;
Microorganisms act both as drivers and indicators of perturbations in the marine environment. In an effort to establish baselines to predict the response of marine habitats to environmental change, here we report a broad survey of microbial diversity across the Indian Ocean, including the first m...
Ann Vanreusel; Annelies De Groote; Sabine Gollner; Monika Bright
Background: Here, insight is provided into the present knowledge on free-living nematodes associated with chemosynthetic environments in the deep sea. It was investigated if the same trends of high standing stock, low diversity, and the dominance of a specialized fauna, as observed for macro-invertebrates, are also present in the nematodes in both vents and seeps. Methodology: This review is based on existing literature, in combination with integrated analysis of datasets, obtained through...
Full Text Available The early Palaeozoic order Ascocerida is a group of morphologically unique and rare cephalopods known from the Ordovician and Silurian rocks of Avalonia, Baltica, Laurentia and Perunica. The limited Estonian record of Silurian ascocerids is complemented with a specimen from the Pähkla locality (Island of Saaremaa; Paadla Regional Stage, Ludlow Series representing the stratigraphically oldest known occurrence of ascocerids in the Silurian of Estonia. The strata that were formerly exposed in Pähkla are likely correlated to the Hemse Group of the Island of Gotland (Sweden having a remarkable record of ascocerids. The appearance of Silurian ascocerids in Estonia is confined to a time interval when the group had the highest species diversity and the widest geographic dispersion, reaching also outside Baltica for the first time.
Carranza, S; Arnold, E N; Pleguezuelos, J M
Variation in 815bp of mitochondrial DNA from two gene fragments (300bp of cytochrome b and 395-515bp of 12S rRNA) for 26 Malpolon monspessulanus, and cytochrome b for a further 21 individuals, indicates that this species originated in the Maghreb area of Northwest Africa. Here, an estimated 3.5-6Mya, it divided into the western M. m. monspessulanus, and an eastern clade including M. m. insignitus and M. m. fuscus. The very limited genetic differentiation between Maghreb and Southwest European populations of this form suggests that it arrived in the Iberian Peninsula only recently. Population genetics and demographic tests indicate subsequent expansion in this area around 83,000-168,000 year ago. Because present populations of Malpolon arrived recently, mid-Pliocene and at least some Pleistocene fossils of the genus Malpolon in Southwest Europe are probably derived from an earlier invasion from the Maghreb, possibly as early as the end of the Miocene period, 5.3-5.9Mya, when there was a temporary land bridge across the site of the Strait of Gibraltar and the Mediterranean Sea desiccated. The descendants of this earlier invasion must have eventually become extinct, perhaps during one of the Pleistocene glaciations. In contrast to the western M. m. monspessulanus, the greater genetic divergence found in the eastern clade of M. monspessulanus suggests that it dispersed at an earlier date and probably over a longer period, spreading eastwards through northern Libya and Egypt to Syria, Iraq, and Iran, and around the Mediterranean Sea through Turkey into the Aegean archipelagos and the Balkan peninsula. The western and eastern units of M. monspessulanus have different dorsal color pattern, differences in skull structure and exhibit an 8.4% uncorrected genetic divergence in the combined gene fragments investigated here. It is consequently recommended that they should be treated as separate species: M. monspessulanus (sensu stricto) and Malpolon insignitusstat. nov., the latter including the subspecies Malpolon insignitus fuscuscomb. nov. The same combined mitochondrial gene fragments used in Malpolon were investigated in 20 individuals of Hemorrhois hippocrepis, and of cytochrome b alone in a further 17. They indicate that this species also originated in the Maghreb and again invaded the Iberian Peninsula quite recently. Some of the most recent invasions of the Iberian Peninsula by reptiles and amphibian taxa could probably be anthropogenic in origin. Some other species including M. monspessulanus and H. hippocrepis, may have crossed naturally, by "hopping" across the Strait of Gibraltar via temporary islands on the shallowest parts that were exposed during sea-level fall associated with Pleistocene glaciations. PMID:16679033
Zhi-hua JIAO; Jian-hua LI
Pachysandra is an eastern Asian-North American disjunct genus with three species, two in eastern Asia (Pachysandra axillaris and Pachysandra terminalis) and one in eastern North America (Pachysandra procumbens). Although morphological and cytological studies suggest a close affinity of Pprocumbens with P axillaris, molecular data from nuclear and chloroplast DNA regions have provided conflicting signals. In this study, we tested previous phylogenetic hypotheses using sequences of nuclear ribosomal DNA internal transcribed spacers and chloroplast ndhF gene from multiple individuals of each of the three species. We also estimated the time of divergence between eastern Asia and eastern North America. Our results support the morphological and cytological conclusion that P procumbens is more closely related to P axillaris than to P terminalis. The estimated time of divergence of P axillaris and P procumbens was 14.64-5.5 mya, consistent with estimates from many other eastern Asian-North American disjunct genera. The migration of Pachysandra populations from eastern Asia to North America might have occurred by way of the North Atlantic land bridge.
Cardenas, Paco; Rapp, Hans Tore; Klitgaard, Anne Birgitte;
Geodia species north of 60 degrees N in the Atlantic appeared in the literature for the first time when Bowerbank described Geodia barretti and G.macandrewii in 1858 from western Norway. Since then, a number of species have been based on material from various parts of the region: G.simplex, Isops...
Full Text Available This is the first comprehensive study of freshwater decapoda crustaceans from Vanuatu. Of the nineteen species collected during this study, eighteen appear to be new records for the archipelago. However none of these species is endemic to Vanuatu, nine having a Pacific distribution and ten an Indo-Pacific distribution. Half of the species recorded were widely distributed in Vanuatu, whereas the others were more restricted. A comparison is made with the freshwater decapoda fauna of the two neighbouring archipelagoes namely, those of Fiji and New Caledonia, which have already been thoroughly surveyed.
Full Text Available Abstract Background In the past ten years, the Indian Ocean region has been the theatre of severe epidemics of chikungunya and dengue. These outbreaks coincided with a high increase in populations of Aedes albopictus that outcompete its sister taxon Aedes aegypti in most islands sampled. The objective of this work was to update the entomological survey of the two Aedes species in the island of Madagascar which has to face these arboviroses. Methods The sampling of Aedes mosquitoes was conducted during two years, from October 2007 to October 2009, in fifteen localities from eight regions of contrasting climates. Captured adults were identified immediately whereas immature stages were bred until adult stage for determination. Phylogenetic analysis was performed using two mtDNA genes, COI and ND5 and trees were constructed by the maximum likelihood (ML method with the gene time reversible (GTR model. Experimental infections with the chikungunya virus strain 06.21 at a titer of 107.5 pfu/mL were performed to evaluate the vector competence of field-collected mosquitoes. Disseminated infection rates were measured fourteen days after infection by immunofluorescence assay performed on head squashes. Results The species Aedes aegypti was detected in only six sites in native forests and natural reserves. In contrast, the species Aedes albopictus was found in 13 out of the 15 sites sampled. Breeding sites were mostly found in man-made environments such as discarded containers, used tires, abandoned buckets, coconuts, and bamboo cuts. Linear regression models showed that the abundance of Ae. albopictus was significantly influenced by the sampling region (F = 62.00, p -16 and period (F = 36.22, p = 2.548 × 10-13, that are associated with ecological and climate variations. Phylogenetic analysis of the invasive Ae. albopictus distinguished haplotypes from South Asia and South America from those of Madagascar, but the markers used were not discriminant enough to discern Malagasy populations. The experimental oral infection method showed that six Ae. albopictus populations exhibited high dissemination infection rates for chikungunya virus ranging from 98 to 100%. Conclusion In Madagascar, Ae. albopictus has extended its geographical distribution whereas, Ae. aegypti has become rare, contrasting with what was previously observed. Changes are predominantly driven by human activities and the rainfall regime that provide suitable breeding sites for the highly anthropophilic mosquito Ae. albopictus. Moreover, these populations were found to be highly susceptible to chikungunya virus. In the light of this study, Ae. albopictus may have been involved in the recent outbreaks of chikungunya and dengue epidemics in Madagascar, and consequently, control measures should be promoted to limit its current expansion.
Robin L Miller-Coleman
Full Text Available Over 100 hot spring sediment samples were collected from 28 sites in 12 areas/regions, while recording as many coincident geochemical properties as feasible (>60 analytes. PCR was used to screen samples for Korarchaeota 16S rRNA genes. Over 500 Korarchaeota 16S rRNA genes were screened by RFLP analysis and 90 were sequenced, resulting in identification of novel Korarchaeota phylotypes and exclusive geographical variants. Korarchaeota diversity was low, as in other terrestrial geothermal systems, suggesting a marine origin for Korarchaeota with subsequent niche-invasion into terrestrial systems. Korarchaeota endemism is consistent with endemism of other terrestrial thermophiles and supports the existence of dispersal barriers. Korarchaeota were found predominantly in >55°C springs at pH 4.7-8.5 at concentrations up to 6.6×10(6 16S rRNA gene copies g(-1 wet sediment. In Yellowstone National Park (YNP, Korarchaeota were most abundant in springs with a pH range of 5.7 to 7.0. High sulfate concentrations suggest these fluids are influenced by contributions from hydrothermal vapors that may be neutralized to some extent by mixing with water from deep geothermal sources or meteoric water. In the Great Basin (GB, Korarchaeota were most abundant at spring sources of pH<7.2 with high particulate C content and high alkalinity, which are likely to be buffered by the carbonic acid system. It is therefore likely that at least two different geological mechanisms in YNP and GB springs create the neutral to mildly acidic pH that is optimal for Korarchaeota. A classification support vector machine (C-SVM trained on single analytes, two analyte combinations, or vectors from non-metric multidimensional scaling models was able to predict springs as Korarchaeota-optimal or sub-optimal habitats with accuracies up to 95%. To our knowledge, this is the most extensive analysis of the geochemical habitat of any high-level microbial taxon and the first application of a C-SVM to microbial ecology.
Atazadeh, Islam; Edlund, Mark B.; van de Vijver, Bart; Mills, Keely; Spaulding, Sarah A.; Gell, Peter A.; Crawford, Simon; Barton, Andrew F.; Lee, Sylvia S.; Smith, Kathryn E.L.; Newall, Peter; Potapova, Marina
Stauroneis pachycephala was described in 1881 from the Baakens River, Port Elizabeth, South Africa. Recently, it was found during surveys of the MacKenzie River (Victoria, Australia), the Florida Everglades (USA) and coastal marshes of Louisiana (USA). The morphology, ecology and geographic distribution of this species are described in this article. This naviculoid species is characterised by lanceolate valves with a gibbous centre, a sigmoid raphe, an axial area narrowing toward the valve ends, and capitate valve apices. The central area is a distinct stauros that is slightly widened near the valve margin. The raphe is straight and filiform, and the terminal raphe fissures are strongly deflected in opposite directions. Striae are fine and radiate in the middle of the valve, becoming parallel and eventually convergent toward the valve ends. The external surface of the valves and copulae is smooth and lacks ornamentation. We also examined the type material of S. pachycephala. Our observations show this species has morphological characteristics that fit within the genus Envekadea. Therefore, the transfer of S. pachycephala to Envekadea is proposed and a lectotype is designated.
Beck, Robin M. D.
Recent molecular data strongly support the monophyly of all extant Australian and New Guinean marsupials (Eomarsupialia) to the exclusion of extant South American marsupials. This, together with available geological and fossil evidence, has been used to argue that the presence of marsupials in Australia is simply the result of a single dispersal event from South America during the latest Cretaceous or Palaeocene, without subsequent dispersals between the two continents. Here, I describe an isolated ankle bone (calcaneus) of a metatherian from the early Eocene Tingamarra Local Fauna in northeastern Australia. Strikingly, this specimen, QM F30060, lacks the `continuous lower ankle joint pattern' (CLAJP), presence of which is a highly distinctive apomorphy of the marsupial clade Australidelphia, which includes Eomarsupialia, the living South American microbiotherian Dromiciops and the Tingamarran fossil marsupial Djarthia. Comparisons with a range of marsupials and stem-metatherians strongly suggest that the absence of the CLAJP in QM F30060 is plesiomorphic, and that this specimen represents the first unequivocal non-australidelphian (`ameridelphian') metatherian known from Australia. This interpretation is confirmed by phylogenetic analyses that place QM F30060 within (crown-group) Marsupialia, but outside Australidelphia. Based on these results, the distribution of marsupials within Gondwana cannot be explained by simply a single dispersal event from South America and Australia. Either there were multiple dispersals by marsupials (and possibly also stem-metatherians) between South America and Australia, in one or both directions, or, alternatively, there was a broadly similar metatherian fauna stretching across southern South America, Antarctica and Australia during the Late Cretaceous-early Palaeogene.
Full Text Available Abstract Background Butterflies of the subtribe Mycalesina (Nymphalidae: Satyrinae are important model organisms in ecology and evolution. This group has radiated spectacularly in the Old World tropics and presents an exciting opportunity to better understand processes of invertebrate rapid radiations. However, the generic-level taxonomy of the subtribe has been in a constant state of flux, and relationships among genera are unknown. There are six currently recognized genera in the group. Mycalesis, Lohora and Nirvanopsis are found in the Oriental region, the first of which is the most speciose genus among mycalesines, and extends into the Australasian region. Hallelesis and Bicyclus are found in mainland Africa, while Heteropsis is primarily Madagascan, with a few species in Africa. We infer the phylogeny of the group with data from three genes (total of 3139 bp and use these data to reconstruct events in the biogeographic history of the group. Results The results indicate that the group Mycalesina radiated rapidly around the Oligocene-Miocene boundary. Basal relationships are unresolved, but we recover six well-supported clades. Some species of Mycalesis are nested within a primarily Madagascan clade of Heteropsis, while Nirvanopsis is nested within Lohora. The phylogeny suggests that the group had its origin either in Asia or Africa, and diversified through dispersals between the two regions, during the late Oligocene and early Miocene. The current dataset tentatively suggests that the Madagascan fauna comprises two independent radiations. The Australasian radiation shares a common ancestor derived from Asia. We discuss factors that are likely to have played a key role in the diversification of the group. Conclusions We propose a significantly revised classification scheme for Mycalesina. We conclude that the group originated and radiated from an ancestor that was found either in Asia or Africa, with dispersals between the two regions and to Australasia. Our phylogeny paves the way for further comparative studies on this group that will help us understand the processes underlying diversification in rapid radiations of invertebrates.
Honda, Masanao; Matsui, Masafumi; Tominaga, Atsushi; Ota, Hidetoshi; Tanaka, Satoshi
The Anderson's crocodile newt, Echinotriton andersoni, is considered a relic and endangered species distributed in the Central Ryukyus. To elucidate phylogenetic relationships and detailed genetic structures among populations, we analyzed variation in the mitochondrial cytochrome b gene. Results strongly support a primary dichotomy between populations from the Amami and Okinawa Island Groups with substantial genetic divergence, favoring a primary divergence between the two island groups. Within the latter, populations from the southern part of Okinawajima Island are shown to be more closely related to those from Tokashikijima Island than to those from the northern and central parts of Okinawajima. The prominent genetic divergence between the two island groups of the Central Ryukyus seems to have initiated in the Miocene, i.e., prior to formation of the strait that has consistently separated these island groups since the Pleistocene. The ancestor of the southern Okinawajima-Tokashikijima is estimated to have migrated from the northern and central parts of Okinawajima into southern Okinawajima at the Pleistocene, and dispersed into Tokashikijima subsequently. PMID:22846685
Borges, Adolfo; Bermingham, Eldredge; Herrera, Nimiadina; Alfonzo, Marcelo J; Sanjur, Oris I
We provide a mitochondrial DNA-based phylogenetic hypothesis for 21 Tityus species collected in Venezuela, Trinidad, Brazil and Panama, including 12 taxa known to be toxic to humans. Our phylogenetic reconstruction is based on 850 nucleotides of the combined cytochrome oxidase subunit I and 16S rRNA genes for most species, and centered on Venezuelan scorpions owing to the detailed taxonomic and biogeographic information available for Tityus in this region. The principal phylogenetic result was the strong support for mtDNA clades representing geographical groupings associated with the Perijá mountain range, the Mérida Andes, or the central and eastern coastal ranges in Venezuela, suggesting that vicariance has been a potent force in the diversification of local scorpions. Venezuelan Tityus species have been organized by González-Sponga into three artificial morphological groups, "androcottoides", "discrepans", and "nematochirus", based on the array of ventral carinae in metasomal segments II-IV. We also incorporated a fourth morphological group ("Tityus clathratus"), recently documented in Venezuela. Our results do not support the clustering of the species in the "androcottoides" and "discrepans" morphological groups, which include the majority of taxa of medical importance, but provided support for the "nematochirus" species group. T. clathratus was found to cluster with the Brazilian T. serrulatus and T. bahiensis. Divergence times of most clades are consistent with major events in the geological history of northern Venezuela and suggest that many Venezuelan Tityus species formed in the late Miocene and the Pliocene. In turn, we used the Tityus mtDNA phylogeny to determine the potential utility of phylogenetic systematics to predict Tityus venom antigenic reactivity by testing the recognition of T. nororientalis, T. discrepans, T. zulianus, T. perijanensis, and T. clathratus venoms by anti-T. discrepans horse antibodies. Cross-reactivity was significantly higher for the closely related eastern (T. nororientalis) and central coastal (T. discrepans) species in comparison to the distantly related Andean (T. zulianus) and Perijá (T. perijanensis) species. Reactivity of T. clathratus low mol. mass toxic components towards anti-T. serrulatus and anti-T. discrepans antivenoms was low, suggesting that venom components produced by the subgenus Archaeotityus (which encompass "clathratus" species) diverge antigenically from other Tityus scorpions. PMID:19799925
Arecaceae tribe Cocoseae is the most economically important tribe of palms, including both coconut and African oil palm. It is mostly represented in the Neotropics, with one and two genera endemic to South Africa and Madagascar, respectively. Using primers for six single copy WRKY gene family loci...
Morden, C.W.; Gardner, D.E.; Weniger, D.A.
The endemic Hawaiian raspberries Rubus hawaiensis and R. macraei (both subgenus Idaeobatus) had been thought to be closely related species until recent molecular studies demonstrated otherwise. These studies suggest that they are the products of separate colonizations to the Hawaiian Islands. Affinities of R. hawaiensis to R. spectabilis of western North America were clearly confirmed. However, no clear relation to R. macraei has been published. This study was initiated to examine species of subg. Idaeobatus from the surrounding Pacific region as well as species from other subgenera to better evaluate biogeographic and phylogenetic affinities of R. macraei by means of chromosome analysis and molecular data using the chloroplast gene ndbF. Results show that R. macraei clusters in a clade with species of blackberries, subg. Rubus, and of these it is most closely linked to R. ursinus. Chromosomally, R. macraei is 2n = 6x = 42, a number that would be a new report for subg. Idaeobatus. However, polyploidy is common in subg. Rubus. Analyses indicate that R. macraei and R. hawaiensis are derived from separate colonizations from North America and that similarities between them are due to convergent evolution in the Hawaiian environment.
Sophie von der Heyden
Full Text Available Numerous studies have demonstrated population genetic structuring in marine species, yet few have investigated the effect of vertical zonation on gene flow and population structure. Here we use three sympatric, closely related clinid species, Clinus cottoides, C. superciliosus and Muraenoclinus dorsalis, to test whether zonation on South African intertidal rocky shores affects phylogeographic patterns. We show that the high‐shore restricted species has reduced gene flow and considerably higher Fst values (Fst = 0.9 than the mid‐ and low‐shore species (Fst
Sophie von der Heyden; Enelge Gildenhuys; Giacomo Bernardi; Bowie, Rauri C. K.
Numerous studies have demonstrated population genetic structuring in marine species, yet few have investigated the effect of vertical zonation on gene flow and population structure. Here we use three sympatric, closely related clinid species, Clinus cottoides, C. superciliosus and Muraenoclinus dorsalis, to test whether zonation on South African intertidal rocky shores affects phylogeographic patterns. We show that the high‐shore restricted species has reduced gene flow and considerably highe...
The guttulinervis group is proposed for a monophyletic group of four northern New Guinean species of the cicada genus Baeturia Stål, 1866. B. guttulinervis Blöte, 1960, is redescribed and three species (B. biroi, B. inconstans, and B. roonensis) are described as new to science. The phylogenetic position of the guttulinervis group, within the genus Baeturia, is discussed. The distribution of shared characters suggests a sister group relationship with the conviva group. A key to the males is pr...
Galbany-Casals, Mercè; Garcia-Jacas, Núria; Sáez, Llorenç; Benedí González, Carles; Susanna de la Serna, Alfonso
[EN] The genus Helichrysum has 500–600 species in Africa, Madagascar, the Mediterranean basin, Macaronesia, western and central Asia, and India. The aims of this study are to confirm the exclusion of Castroviejoa from Helichrysum, to elucidate the origin of the Macaronesian endemics, to confirm the monophyly of the Mediterranean-Asiatic group, and, within this group, to contrast molecular data with sectional classification and to provide insight into trends in character evolution ...
Bürki, Sven; Küpfer, Philippe; Alvarez, Nadir
La famille des Sapindaceae est importante d’un point de vue économique et comprend plus de 1900 espèces (distribuées dans approximativement 140 genres; par exemple Litchi, Paullinia), majoritairement distribuées en zone tropicale. Cependant, certains genres peuvent coloniser les zones tempérées. Depuis plus d’un siècle, la définition de cette famille (plus particulièrement la possible inclusion des Aceraceae et Hippocastanacae au sein des Sapindaceae) ainsi que les relations entre les sous-fa...
Jeffries, Thomas C.; Ostrowski, Martin; Williams, Rohan B.; Xie, Chao; Jensen, Rachelle M.; Grzymski, Joseph J.; Senstius, Svend Jacob; Givskov, Michael; Hoeke, Ron; Philip, Gayle K.; Neches, Russell Y.; Drautz-Moses, Daniela I.; Chénard, Caroline; Paulsen, Ian T.; Lauro, Federico M.
Microorganisms act both as drivers and indicators of perturbations in the marine environment. In an effort to establish baselines to predict the response of marine habitats to environmental change, here we report a broad survey of microbial diversity across the Indian Ocean, including the first microbial samples collected in the pristine lagoon of Salomon Islands, Chagos Archipelago. This was the first large-scale ecogenomic survey aboard a private yacht employing a ‘citizen oceanography’ approach and tools and protocols easily adapted to ocean going sailboats. Our data highlighted biogeographic patterns in microbial community composition across the Indian Ocean. Samples from within the Salomon Islands lagoon contained a community which was different even from adjacent samples despite constant water exchange, driven by the dominance of the photosynthetic cyanobacterium Synechococcus. In the lagoon, Synechococcus was also responsible for driving shifts in the metatranscriptional profiles. Enrichment of transcripts related to photosynthesis and nutrient cycling indicated bottom-up controls of community structure. However a five-fold increase in viral transcripts within the lagoon during the day, suggested a concomitant top-down control by bacteriophages. Indeed, genome recruitment against Synechococcus reference genomes suggested a role of viruses in providing the ecological filter for determining the β-diversity patterns in this system.
Tamar, Karin; Scholz, Sebastian; Crochet, Pierre-André; Geniez, Philippe; Meiri, Shai; Schmitz, Andreas; Wilms, Thomas; Carranza, Salvador
Since the Oligocene, regions adjacent to the Red Sea have experienced major environmental changes, from tectonic movements and continuous geological activity to shifting climatic conditions. The effect of these events on the distribution and diversity of the regional biota is still poorly understood. Agamid members of the genus Pseudotrapelus are diurnal, arid-adapted lizards distributed around the Red Sea from north-eastern Africa, across the mountains and rocky plateaus of the Sinai and Arabian Peninsulas northwards to Syria. Despite recent taxonomic work and the interest in the group as a model for studying biogeographic and diversity patterns of the arid areas of North Africa and Arabia, its taxonomy is poorly understood and a comprehensive phylogeny is still lacking. In this study, we analyzed 92 Pseudotrapelus specimens from across the entire distribution range of the genus. We included all known species and subspecies, and sequenced them for mitochondrial (16S, ND4 and tRNAs) and nuclear (MC1R, c-mos) markers. This enabled us to obtain the first time-calibrated molecular phylogeny of the genus, using gene trees, species trees and coalescent-based methods for species delimitation. Our results revealed Pseudotrapelus as a monophyletic genus comprised of two major clades and six independently evolving lineages. These lineages correspond to the five currently recognized species and a sixth lineage relating to the synonymized P. neumanni. The subspecific validity of P. sinaitus werneri needs further assessment as it does not form a distinct cluster relative to P. s. sinaitus. The onset of Pseudotrapelus diversification is estimated to have occurred in Arabia during the late Miocene. Radiation has likely resulted from vicariance and dispersal events due to the continued geological instability, sea level fluctuations and climatic changes within the region. PMID:26772670
Fernando Abad-Franch; Fernando A Monteiro
An ecological-evolutionary classification of Amazonian triatomines is proposed based on a revision of their main contemporary biogeographical patterns. Truly Amazonian triatomines include the Rhodniini, the Cavernicolini, and perhaps Eratyrus and some Bolboderini. The tribe Rhodniini comprises two major lineages (pictipes and robustus). The former gave rise to trans-Andean (pallescens) and Amazonian (pictipes) species groups, while the latter diversified within Amazonia (robustus group) and r...
Full Text Available An ecological-evolutionary classification of Amazonian triatomines is proposed based on a revision of their main contemporary biogeographical patterns. Truly Amazonian triatomines include the Rhodniini, the Cavernicolini, and perhaps Eratyrus and some Bolboderini. The tribe Rhodniini comprises two major lineages (pictipes and robustus. The former gave rise to trans-Andean (pallescens and Amazonian (pictipes species groups, while the latter diversified within Amazonia (robustus group and radiated to neighbouring ecoregions (Orinoco, Cerrado-Caatinga-Chaco, and Atlantic Forest. Three widely distributed Panstrongylus species probably occupied Amazonia secondarily, while a few Triatoma species include Amazonian populations that occur only in the fringes of the region. T. maculata probably represents a vicariant subset isolated from its parental lineage in the Caatinga-Cerrado system when moist forests closed a dry trans-Amazonian corridor. These diverse Amazonian triatomines display different degrees of synanthropism, defining a behavioural gradient from household invasion by adult triatomines to the stable colonisation of artificial structures. Anthropogenic ecological disturbance (driven by deforestation is probably crucial in the onset of the process, but the fact that only a small fraction of species effectively colonises artificial environments suggests a role for evolution at the end of the gradient. Domestic infestation foci are restricted to drier subregions within Amazonia; thus, populations adapted to extremely humid rainforest microclimates may have limited chances of successfully colonising the slightly drier artificial microenvironments. These observations suggest several research avenues, from the use of climate data to map risk areas to the assessment of the synanthropic potential of individual vector species.
Doadrio, Ignacio; Perea, Silvia; Alcaraz, Lourdes; Hernandez, Natividad
Phylogenetic relationships among members of the freshwater fish tribe Girardinini were inferred to test existing colonization and diversification hypotheses for this group in the Caribbean. The genetic material examined was mitochondrial (cytochrome b, 1140 bp) and nuclear (RAG-1 and beta-actin, 2450 bp) DNA from 161 specimens representing 44 ingroup and three outgroup taxa. Our mtDNA and combined data matrix (mtDNA+nuclear DNA) results rendered a well-supported phylogeny for the tribe Girardinini and suggest the need to review the group's current taxonomy. From the data presented here, it may be inferred that the Girardinini diverged from other poeciliid fishes approximately 62 Mya ago in the Palaeocene period. This estimate, however, conflicts with the hypothesis that today's vertebrate fauna is the result of the more recent colonization of the Antillean islands during the Early Oligocene (35-33 Mya ago). The isolation of western, central and eastern Cuba during the Miocene and that of the Juventud Island and Guanahacabibes Peninsula during the Pliocene, are the main geologic events that could have promoted speciation in this group. PMID:18854217
Graham, B. S.; Fry, B.; Popp, B. N.; Allain, V.; Olson, R.; Galvan, F.
By mapping the δ15N and δ13C values of three top-level pelagic predators, yellowfin (Thunnus albacares), bigeye (T. obesus), and skipjack (Katsuwonus pelamis) tuna throughout the equatorial Pacific Ocean, we demonstrated systematic geographic isotopic variation (up to ~12‰ for the δ15N values) that reflect nutrient dynamics that occur at the base of the food web. Remarkably the variation observed in the δ15N values of the tunas is geographically similar to δ15N values previously reported in surface particulate organic matter and deep-sea sediments in the tropical Pacific. We discuss the mechanisms occurring at the base of the food web that could produce the spatial variability observed in tropical tuna δ15N values. We present a simple Rayleigh fractionation model that can explain much of the spatial structure. We also discuss the temporal stability in the isotopic compositions at the base and top of the food web. Overall, this nitrogen isotope cartography or “isoscapes” suggests nitrogen is tightly retained in the marine food web, up to the top predators, and that the uptake of nitrate from the equatorial upwelling zone, denitrification in the oxygen minimum zones, and nitrogen fixation at the base of the food web play major roles in the observed geographical variation. In addition to providing insight into the nutrient dynamics of the open ocean, these predator isoscapes can begin to be used to characterize regional residency in tropical tunas, which is important for the successful management of tuna fisheries.
Nunney, Leonard; Ortiz, Beatriz; Russell, Stephanie A; Ruiz Sánchez, Rebeca; Stouthamer, Richard
The bacterium Xylella fastidiosa is a plant pathogen with a history of economically damaging introductions of subspecies to regions where its other subspecies are native. Genetic evidence is presented demonstrating the introduction of two new taxa into Central America and their introgression into the native subspecies, X. fastidiosa subsp. fastidiosa. The data are from 10 genetic outliers detected by multilocus sequence typing (MLST) of isolates from Costa Rica. Six (five from oleander, one from coffee) defined a new sequence type (ST53) that carried alleles at six of the eight loci sequenced (five of the seven MLST loci) diagnostic of the South American subspecies Xylella fastidiosa subsp. pauca which causes two economically damaging plant diseases, citrus variegated chlorosis and coffee leaf scorch. The two remaining loci of ST53 carried alleles from what appears to be a new South American form of X. fastidiosa. Four isolates, classified as X. fastidiosa subsp. fastidiosa, showed a low level of introgression of non-native DNA. One grapevine isolate showed introgression of an allele from X. fastidiosa subsp. pauca while the other three (from citrus and coffee) showed introgression of an allele with similar ancestry to the alleles of unknown origin in ST53. The presence of X. fastidiosa subsp. pauca in Central America is troubling given its disease potential, and establishes another route for the introduction of this economically damaging subspecies into the US or elsewhere, a threat potentially compounded by the presence of a previously unknown form of X. fastidiosa. PMID:25379725
Mende, Michael; Hundsdörfer, Anna
Background: Mitochondrial genes are among the most commonly used markers in studies of species’ phylogeography and to draw conclusions about taxonomy. The Hyles euphorbiae complex (HEC) comprises six distinct mitochondrial lineages in the Mediterranean region, of which one exhibits a cryptic disjunct distribution. The predominant mitochondrial lineage in most of Europe, euphorbiae, is also present on Malta; however, it is nowadays strangely absent from Southern Italy and Sicily, where it is r...
Sintes, Eva; Bergauer, Kristin; de Corte, Daniele; Yokokawa, Taichi; Herndl, Gerhard J.
Mesophilic ammonia-oxidizing Archaea (AOA) are abundant in a diverse range of marine environments, including the deep ocean, as revealed by the quantification of the archaeal amoA gene encoding the alpha-subunit of the ammonia monooxygenase. Using two different amoA primer sets, two distinct ecotypes of marine Crenarchaeota Group I (MCGI) were detected in the waters of the tropical Atlantic and the coastal Arctic. The HAC-AOA ecotype (high ammonia concentration AOA) was ≍ 8000 times and 15 ti...
Sintes, Eva; Bergauer, Kristin; De Corte, Daniele; Yokokawa, Taichi; Herndl, Gerhard J.
Mesophilic ammonia-oxidizing Archaea (AOA) are abundant in a diverse range of marine environments, including the deep ocean, as revealed by the quantification of the archaeal amoA gene encoding the alpha-subunit of the ammonia monooxygenase. Using two different amoA primer sets, two distinct ecotype
Gooday, A.J.; Cedhagen, Tomas; Kamenskaya, O.E.;
families Komokiidae and Baculellidae, respectively, and another 2 to the Komokiacea incertae sedis. We include in the Baculellidae an undescribed species in which very fine hair-like fibres, similar to those seen in some species currently included in this family, arise from the segments that make up the...... depths in the oceans. They also support other evidence that many undescribed komokiacean species exist and highlight some of the difficulties involved in defining the morphological limits of this difficult taxon....
Fine, P.; Zapata, F.; Daly, D.
Andean uplift and the collision of North and South America are thought to have major implications for the diversification of the Neotropical biota. However, few studies have investigated how these geological events may have influenced diversification. We present a multilocus phylogeny of 102 Protieae taxa (73% of published species), sampled pantropically, to test hypotheses about the relative importance of dispersal, vicariance, habitat specialization, and biotic factors in the diversification of this ecologically dominant tribe of Neotropical trees. Bayesian fossil-calibrated analyses date the Protieae stem at 55 Mya. Biogeographic analyses reconstruct an initial late Oligocene/early Miocene radiation in Amazonia for Neotropical Protieae, with several subsequent late Miocene dispersal events to Central America, the Caribbean, Brazil's Atlantic Forest, and the Chocó. Regional phylogenetic structure results indicate frequent dispersal among regions throughout the Miocene and many instances of more recent regional in situ speciation. Habitat specialization to white sand or flooded soils was common, especially in Amazonia. There was one significant increase in diversification rate coincident with colonization of the Neotropics, followed by a gradual decrease consistent with models of diversity-dependent cladogenesis. Dispersal, biotic interactions, and habitat specialization are thus hypothesized to be the most important processes underlying the diversification of the Protieae.
Štefka, Jan; Hypša, Václav; Scholz, Tomáš
Roč. 18, č. 6 (2009), s. 1187-1206. ISSN 0962-1083 R&D Projects: GA MŠk LC06073; GA ČR GA524/08/0885; GA MŠk LC522 Institutional research plan: CEZ:AV0Z60220518 Keywords : cryptic speciation * geographical isolation * host specificity * microsatellites * parasite * population structure Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine Impact factor: 5.960, year: 2009
Chomicki, Guillaume; Renner, Susanne S
Ecological research on ant/plant symbioses in Fiji, combined with molecular phylogenetics, has brought to light four new species of Squamellaria in the subtribe Hydnophytinae of the Rubiaceae tribe Psychotrieae and revealed that four other species, previously in Hydnophytum, need to be transferred to Squamellaria. The diagnoses of the new species are based on morphological and DNA traits, with further insights from microCT scanning of flowers and leaf δ(13)C ratios (associated with Crassulacean acid metabolism). Our field and phylogenetic work results in a new circumscription of the genus Squamellaria, which now contains 12 species (to which we also provide a taxonomic key), not 3 as in the last revision. A clock-dated phylogeny and a model-testing biogeographic framework were used to infer the broader geographic history of rubiaceous ant plants in the Pacific, specifically the successive expansion of Squamellaria to Vanuatu, the Solomon Islands, and Fiji. The colonization of Vanuatu may have occurred from Fiji, when these islands were still in the same insular arc, while the colonization of the Solomon islands may have occurred after the separation of this island from the Fiji/Vanuatu arc. Some of these ant-housing epiphytes must have dispersed with their specialized ants, for instance attached to floating timber. Others acquired new ant symbionts on different islands. PMID:27028599
Full Text Available Intercontinental disjunctions between tropical regions, which harbor two-thirds of the flowering plants, have drawn great interest from biologists and biogeographers. Most previous studies on these distribution patterns focused on woody plants, and paid little attention to herbs. The Orchidaceae is one of the largest families of angiosperms, with a herbaceous habit and a high species diversity in the Tropics. Here we investigate the evolutionary and biogeographical history of the slipper orchids, which represents a monophyletic subfamily (Cypripedioideae of the orchid family and comprises five genera that are disjunctly distributed in tropical to temperate regions. A relatively well-resolved and highly supported phylogeny of slipper orchids was reconstructed based on sequence analyses of six maternally inherited chloroplast and two low-copy nuclear genes (LFY and ACO. We found that the genus Cypripedium with a wide distribution in the northern temperate and subtropical zones diverged first, followed by Selenipedium endemic to South America, and finally conduplicate-leaved genera in the Tropics. Mexipedium and Phragmipedium from the neotropics are most closely related, and form a clade sister to Paphiopedilum from tropical Asia. According to molecular clock estimates, the genus Selenipedium originated in Palaeocene, while the most recent common ancestor of conduplicate-leaved slipper orchids could be dated back to the Eocene. Ancestral area reconstruction indicates that vicariance is responsible for the disjunct distribution of conduplicate slipper orchids in palaeotropical and neotropical regions. Our study sheds some light on mechanisms underlying generic and species diversification in the orchid family and tropical disjunctions of herbaceous plant groups. In addition, we suggest that the biogeographical study should sample both regional endemics and their widespread relatives.
Amanda V Rocha
Full Text Available Coalescent theory provides powerful models for population genetic inference and is now increasingly important in estimates of divergence times and speciation research. We use molecular data and methods based on coalescent theory to investigate whether genetic evidence supports the hypothesis of A. pretrei and A. tucumana as separate species and whether genetic data allow us to assess which allopatric model seems to better explain the diversification process in these taxa. We sampled 13 A. tucumana from two provinces in northern Argentina and 28 A. pretrei from nine localities of Rio Grande do Sul, Brazil. A 491 bp segment of the mitochondrial gene cytochrome c oxidase I was evaluated using the haplotype network and phylogenetic methods. The divergence time and other demographic quantities were estimated using the isolation and migration model based on coalescent theory. The network and phylogenetic reconstructions showed similar results, supporting reciprocal monophyly for these two taxa. The divergence time of lineage separation was estimated to be approximately 1.3 million years ago, which corresponds to the lower Pleistocene. Our results enforce the current taxonomic status for these two Amazon species. They also support that A. pretrei and A. tucumana diverged with little or no gene flow approximately 1.3 million years ago, most likely after the establishment of a small population in the Southern Yungas forest by dispersion of a few founders from the A. pretrei ancestral population. This process may have been favored by habitat corridors formed in hot and humid periods of the Quaternary. Considering that these two species are considered threatened, the results were evaluated for their implications for the conservation of these two species.
Renner, Susanne S; Zhang, Li-Bing
Pistia stratiotes (water lettuce) and Lemna (duckweeds) are the only free-floating aquatic Araceae. The geographic origin and phylogenetic placement of these unrelated aroids present long-standing problems because of their highly modified reproductive structures and wide geographical distributions. We sampled chloroplast (trnL-trnF and rpl20-rps12 spacers, trnL intron) and mitochondrial sequences (nad1 b/c intron) for all genera implicated as close relatives of Pistia by morphological, restriction site, and sequencing data, and present a hypothesis about its geographic origin based on the consensus of trees obtained from the combined data, using Bayesian, maximum likelihood, parsimony, and distance analyses. Of the 14 genera closest to Pistia, only Alocasia, Arisaema, and Typhonium are species-rich, and the latter two were studied previously, facilitating the choice of representatives that span the roots of these genera. Results indicate that Pistia and the Seychelles endemic Protarum sechellarum are the basalmost branches in a grade comprising the tribes Colocasieae (Ariopsis, Steudnera, Remusatia, Alocasia, Colocasia), Arisaemateae (Arisaema, Pinellia), and Areae (Arum, Biarum, Dracunculus, Eminium, Helicodiceros, Theriophonum, Typhonium). Unexpectedly, all Areae genera are embedded in Typhonium, which throws new light on the geographic history of Areae. A Bayesian analysis of divergence times that explores the effects of multiple fossil and geological calibration points indicates that the Pistia lineage is 90 to 76 million years (my) old. The oldest fossils of the Pistia clade, though not Pistia itself, are 45-my-old leaves from Germany; the closest outgroup, Peltandreae (comprising a few species in Florida, the Mediterranean, and Madagascar), is known from 60-my-old leaves from Europe, Kazakhstan, North Dakota, and Tennessee. Based on the geographic ranges of close relatives, Pistia likely originated in the Tethys region, with Protarum then surviving on the Seychelles, which became isolated from Madagascar and India in the Late Cretaceous (85 my ago). Pistia and Protarum provide striking examples of ancient lineages that appear to have survived in unique or isolated habitats. PMID:15503671
Sushma REDDY; rpd S NYRI
The Streak-breasted Scimitar Babblers of thePomatorhinus ruficollis species complex are found in most of the fo-rested habitats across southern and eastern Asia. The diversification history of this group is obscured by high plumage variation across populations and conflicting genetic signal across loci. We combined genetic and geographic data from several recent stu-dies to investigate how these species diversified across China using both phylogenetic and ecological niche modeling analyses. These two lines of evidence are consistent in showing that two well-sampled species,P. reconditus andP. nigrostellatus,in cen-tral and southern China respectively, likely experienced a history of isolation and expansion as suitable habitat contracted during the last interglacial and expanded in patchy extent during the glacial maximum. The genetic analysis showed that populations ofP. nigrostellatus on Hainan Island are very similar to the ones in nearby mainland southern China. We recovered two well-supported clades withinP. reconditus that were not geographically structured with both containing individuals from the same localities across central China. This phylogenetic result corresponded to the ecological niche models that showed expansion from refugia since the last interglacial. This study illustrates the value of using an integrative approach and detailed geographic sampling to help understand the recent diversification of birds in China [Current Zoology 61 (5): 910–921, 2015].
Full Text Available Ecological research on ant/plant symbioses in Fiji, combined with molecular phylogenetics, has brought to light four new species of Squamellaria in the subtribe Hydnophytinae of the Rubiaceae tribe Psychotrieae and revealed that four other species, previously in Hydnophytum, need to be transferred to Squamellaria. The diagnoses of the new species are based on morphological and DNA traits, with further insights from microCT scanning of flowers and leaf δ13C ratios (associated with Crassulacean acid metabolism. Our field and phylogenetic work results in a new circumscription of the genus Squamellaria, which now contains 12 species (to which we also provide a taxonomic key, not 3 as in the last revision. A clock-dated phylogeny and a model-testing biogeographic framework were used to infer the broader geographic history of rubiaceous ant plants in the Pacific, specifically the successive expansion of Squamellaria to Vanuatu, the Solomon Islands, and Fiji. The colonization of Vanuatu may have occurred from Fiji, when these islands were still in the same insular arc, while the colonization of the Solomon islands may have occurred after the separation of this island from the Fiji/Vanuatu arc. Some of these ant-housing epiphytes must have dispersed with their specialized ants, for instance attached to floating timber. Others acquired new ant symbionts on different islands.
Chomicki, Guillaume; Renner, Susanne S.
Ecological research on ant/plant symbioses in Fiji, combined with molecular phylogenetics, has brought to light four new species of Squamellaria in the subtribe Hydnophytinae of the Rubiaceae tribe Psychotrieae and revealed that four other species, previously in Hydnophytum, need to be transferred to Squamellaria. The diagnoses of the new species are based on morphological and DNA traits, with further insights from microCT scanning of flowers and leaf δ 13 C ratios (associated with Crassulace...
National Oceanic and Atmospheric Administration, Department of Commerce — This dataset represents hard bottom occurrence predictions from a spatial model developed for the New York offshore spatial planning area. This model builds upon...
The Upper Green River flows southward out of the Green River Basin through a series of deep canyons across the Uinta Mountains in a course that post-dates the deposition of the Bishop Conglomerate (Oligocene). After the Eocene lakes disappeared, drainage was generally eastward across the present Continental Divide, until the Green River was captured near Green River, Wyo. by south-flowing drainage in middle Pleistocene time, ca., 600 kyr ago. Capture of the Upper Green River as recently as middle Pleistocene time, if a valid hypothesis, must take into account the marked differences between the endemic and indigenous fish fauna of the Green River and that of the North Platte. -from Author
Sychra, O.; Kounek, F.; Najer, T.; Hung, N. M.; Haljian, A.; Procházka, Petr; Čapek, Miroslav; Literák, I.
Park City: International Society of Phthirapterists, 2014. s. 64-65. [International Conference on Phthiraptera /5./. 02.08.2014-07.08.2014, Park City] Institutional support: RVO:68081766 Keywords : chewing lice Subject RIV: EG - Zoology
Kopalová, Kateřina; Nedbalová, Linda; Nývlt, D.; Elster, Josef; Van de Vijver, B.
Roč. 36, č. 7 (2013), s. 933-948. ISSN 0722-4060 R&D Projects: GA MŠk ME 934; GA MŠk ME 945 Institutional support: RVO:67985939 Keywords : diatoms * lakes * seepages Subject RIV: EH - Ecology, Behaviour Impact factor: 2.071, year: 2013
Continuing pressures from human activities harm the health of ocean ecosystems, particularly near the coast. Traditional management practices operating on one use sector at a time have not resulted in healthy oceans that can sustainably provide the ecosystem services humans want ...
Rodríguez, J.; Hortal, Joaquín; Nieto, M.
Aim To evaluate the influence of environment and biogeographical region, as a proxy for historical influence, on the ecological structure of Holarctic communities from similar environments. It is assumed that similarities among communities from similar environments in different realms are the res...
Klečková, Irena; Cesanek, M.; Fric, Zdeněk; Pellissier, L.
Roč. 92, NOV 01 (2015), s. 255-265. ISSN 1055-7903 R&D Projects: GA ČR GAP505/10/2248 Grant ostatní: GA JU(CZ) 106/2010/P; GA JU(CZ) 135/2010/P Institutional support: RVO:60077344 Keywords : molecular systematics * Lepidoptera * temperate Subject RIV: EH - Ecology, Behaviour Impact factor: 3.916, year: 2014 http://www.sciencedirect.com/science/article/pii/S1055790315001827
Pandolfi, Luca; Gasparik, Mihály; Magyar, Imre
Although the rhinoceros remains have high biochronological significance, they are poorly known or scarcely documented in the uppermost Miocene deposits of Europe. Several specimens collected from the Upper Miocene (around 7.0 Ma, Turolian) deposits of Kávás (Pannonian Basin, Western Hungary), previously determined as Rhinoceros sp., are revised and described in this paper. The postcranial remains of these specimens belong to "Dihoplus" megarhinus (de Christol) on the basis of the morphological and morphometric characters of humerus, radii, metacarpal and metatarsal elements. An overview of rhinoceros remains from several uppermost Miocene localities and the revision of the rhinoceros material from the Pannonian Basin suggest that "D." megarhinus spread during the latest Miocene from the Pannonian Basin towards Italy. The occurrences of this species in Western Hungary and Italy during the latest Miocene further imply that Rhinocerotini species were biogeographically segregated between Western, Southern and Central Europe.
Dimitrov, Dimitar Stefanov; Astrin, Jonas J.; Huber, Bernhard A.
We analysed seven genetic markers sampled from 165 pholcids and 34 outgroups in order to test and improve the recently revised classification of the family. Our results are based on the largest and most comprehensive set of molecular data so far to study pholcid relationships. The data were analy...
Murphy, W J; Collier, G E
We examined the phylogenetic relationships of 16 northern species of the aplocheiloid genus Rivulus inhabiting the Caribbean, Central America, and South America. A total of 714 base pairs per taxon were sequenced from two segments of the mitochondrial genome, 12S rRNA and cytochrome b. Both parsimony and neighbor-joining analyses suggest an ancient vicariant origin of the Greater Antillean taxa, in addition to a quite recent dispersal of species into the Lesser Antilles from the South American mainland. Combined analyses support the monophyly of the northern South American assemblage as the sister group of a Central American/Columbian biota. However, the monophyly of the Central American biota remains uncertain. Divergence estimates for the Central American taxa are calibrated from the Last Cretaceous separation of the proto-Antilles from the Americas. These data suggest that the extant Central American taxa represent the descendants of at least two separate invasions during the Cenozoic, prior to the closing of the Panamanian isthmus. Times are consistent with the extensive evidence for reptilian and mammalian exchange throughout the Cenozoic. PMID:8676738
Pérez, Gustavo A Concheiro; Rícan, Oldrich; Ortí, Guillermo; Bermingham, Eldredge; Doadrio, Ignacio; Zardoya, Rafael
Heroini constitute the second largest tribe of Neotropical cichlids and show their greatest diversity in Mesoamerica. Although heroine species are morphologically and ecologically very diverse, they were all historically assigned to one single genus, Cichlasoma that was never formally revised from a phylogenetic point of view. Here, we present the most comprehensive molecular phylogeny of the tribe Heroini to date, based on the complete DNA sequence of the mitochondrial gene cytochrome b, and the analysis of 204 individuals representing 91 species. Phylogenetic analyses did not support the monophyly of heroines because the genus Pterophyllum was placed as the sister group of all remaining heroines plus cichlasomatines. However, the recovered relative position of Pterophyllum was without strong statistical support. Within the remaining heroines, Hyspelecara and Hoplarchus are recovered with low support in a basal position with respect to a clade that includes Heros, Uaru, Mesonauta, and Symphysodon, and the circumamazonian (CAM) heroines. The first clade is restricted to South America. The largest clade of heroines, the CAM heroines, include more than 85% of the species within the tribe. This clade is mostly Mesoamerican, but also contains four species found in the Greater Antilles (Nandopsis), and three genera found in South America (the 'Heros' festae group, Australoheros, and Caquetaia). Up to eight major lineages can be recovered within the CAM heroines, but the phylogenetic relationships among them remain unresolved. Two large suprageneric groups can be distinguished, the amphilophines and the herichthyines. The amphilophines include Amphilophus, Archocentrus, Hypsophrys, Neetroplus, Parachromis, Petenia, and five additional unnamed genera (the 'Heros' istlanus group, the 'Amphilophus' calobrensis group, the 'Heros' urophthalmus group, the 'Heros' wesseli group, and the 'Heros' sieboldii group). The herichthyines include the crown-group herichthyines (Herichthys, Theraps, Vieja, and Paratheraps) and the genera Tomocichla, Herotilapia, and Thorichthys, together with three unnamed genera (the 'Heros' umbriferus group, the 'Heros' grammodes group, and the 'Heros' salvini group). Amphilophines are prevalent in southern Mesomerica south of the Motagua fault. Herichthyines have basal linages in Central America, whereas crown-group herichthyines and three related genera are found north from the Motagua fault. At least two independent origins are required to explain current Mesoamerican heroine distribution. Dispersal of heroines from South America into Mesoamerica was dated between 24 and 16 million years ago (MYA) based on geological calibrations and on standard fish mitochondrial cytochrome b rates, respectively. These datings cannot be reconciled with currently known geological evidence, and the existence of a connection between Central America and South America in the Miocene needs to be postulated in order to explain the origins of Mesoamerican heroine lineages. However, our datings agree with those estimated for the dispersal of other secondary freshwater fishes (Rivulidae, Synbranchus) into Mesoamerica, and predate the invasion of primary freshwater fishes by at least 10 myr. PMID:17045493
The bloetei group is proposed for a monophyletic group of 18 species of the genus Baeturia Stål, 1866. Fifteen species are described as new ( B. bilebanarai, B. bismarckensis, B. bloetei, B. boulardi, B. brandti, B. cristovalensis, B. gressitti, B. macgillavryi, B. manusensis, B. marginata, B. mendanai, B. mussauensis, B. papuensis, B. reijnhoudti and B. sedlacekorum) and three species ( B. edauberti Boulard, B. maddisoni Duffels and B. rotumae Duffels) are redescribed. B. aubertae Boulard, B...
Boer, de A.J.
The bloetei group is proposed for a monophyletic group of 18 species of the genus Baeturia Stål, 1866. Fifteen species are described as new ( B. bilebanarai, B. bismarckensis, B. bloetei, B. boulardi, B. brandti, B. cristovalensis, B. gressitti, B. macgillavryi, B. manusensis, B. marginata, B. menda
Full Text Available Copepoda is one of the most prominent higher taxa with almost 80 described species at deep-sea hydrothermal vents. The unique copepod family Dirivultidae with currently 50 described species is the most species rich invertebrate family at hydrothermal vents.We reviewed the literature of Dirivultidae and provide a complete key to species, and map geographical and habitat specific distribution. In addition we discuss the ecology and origin of this family.Dirivultidae are only present at deep-sea hydrothermal vents and along the axial summit trough of midocean ridges, with the exception of Dirivultus dentaneus found associated with Lamellibrachia species at 1125 m depth off southern California. To our current knowledge Dirivultidae are unknown from shallow-water vents, seeps, whale falls, and wood falls. They are a prominent part of all communities at vents and in certain habitat types (like sulfide chimneys colonized by pompei worms they are the most abundant animals. They are free-living on hard substrate, mostly found in aggregations of various foundation species (e.g. alvinellids, vestimentiferans, and bivalves. Most dirivultid species colonize more than one habitat type. Dirivultids have a world-wide distribution, but most genera and species are endemic to a single biogeographic region. Their origin is unclear yet, but immigration from other deep-sea chemosynthetic habitats (stepping stone hypothesis or from the deep-sea sediments seems unlikely, since Dirivultidae are unknown from these environments. Dirivultidae is the most species rich family and thus can be considered the most successful taxon at deep-sea vents.
Miller-Coleman, Robin L; Dodsworth, Jeremy A; Ross, Christian A; Shock, Everett L; Williams, Amanda J; Hartnett, Hilairy E; McDonald, Austin I; Havig, Jeff R; Hedlund, Brian P
Over 100 hot spring sediment samples were collected from 28 sites in 12 areas/regions, while recording as many coincident geochemical properties as feasible (>60 analytes). PCR was used to screen samples for Korarchaeota 16S rRNA genes. Over 500 Korarchaeota 16S rRNA genes were screened by RFLP analysis and 90 were sequenced, resulting in identification of novel Korarchaeota phylotypes and exclusive geographical variants. Korarchaeota diversity was low, as in other terrestrial geothermal systems, suggesting a marine origin for Korarchaeota with subsequent niche-invasion into terrestrial systems. Korarchaeota endemism is consistent with endemism of other terrestrial thermophiles and supports the existence of dispersal barriers. Korarchaeota were found predominantly in >55°C springs at pH 4.7-8.5 at concentrations up to 6.6×10(6) 16S rRNA gene copies g(-1) wet sediment. In Yellowstone National Park (YNP), Korarchaeota were most abundant in springs with a pH range of 5.7 to 7.0. High sulfate concentrations suggest these fluids are influenced by contributions from hydrothermal vapors that may be neutralized to some extent by mixing with water from deep geothermal sources or meteoric water. In the Great Basin (GB), Korarchaeota were most abundant at spring sources of pHapplication of a C-SVM to microbial ecology. PMID:22574130
Pinto-Sánchez, Nelsy Rocío; Calderón-Espinosa, Martha L; Miralles, Aurélien; Crawford, Andrew J; Ramírez-Pinilla, Martha Patricia
Understanding the phylogenetic and geographical history of Neotropical lineages requires having adequate geographic and taxonomic sampling across the region. However, Colombia has remained a geographical gap in many studies of Neotropical diversity. Here we present a study of Neotropical skinks of the genus Mabuya, reptiles that are difficult to identify or delimit due to their conservative morphology. The goal of the present study is to propose phylogenetic and biogeographic hypotheses of Mabuya including samples from the previously under-studied territory of Colombia, and address relevant biogeographic and taxonomic issues. We combined molecular and morphological data sampled densely by us within Colombia with published data representing broad sampling across the Neotropical realm, including DNA sequence data from two mitochondrial (12S rRNA and cytochrome b) and three nuclear genes (Rag2, NGFB and R35). To evaluate species boundaries we employed a general mixed Yule-coalescent (GMYC) model applied to the mitochondrial data set. Our results suggest that the diversity of Mabuya within Colombia is higher than previously recognized, and includes lineages from Central America and from eastern and southern South America. The genus appears to have originated in eastern South America in the Early Miocene, with subsequent expansions into Central America and the Caribbean in the Late Miocene, including at least six oceanic dispersal events to Caribbean Islands. We identified at least four new candidate species for Colombia and two species that were not previously reported in Colombia. The populations of northeastern Colombia can be assigned to M. zuliae, while specimens from Orinoquia and the eastern foothills of the Cordillera Oriental of Colombia correspond to M. altamazonica. The validity of seven species of Mabuya sensu lato was not supported due to a combination of three factors: (1) non-monophyly, (2) <75% likelihood bootstrap support and <0.95 Bayesian posterior probability, and (3) GMYC analysis collapsing named species. Finally, we suggest that Mabuya sensu stricto may be regarded as a diverse monophyletic genus, widely distributed throughout the Neotropics. PMID:26234274
Full Text Available Parsimony analysis of endemicity (PAE was used to identify areas of endemism (AOEs for Chinese birds at the subregional level. Four AOEs were identified based on a distribution database of 105 endemic species and using 18 avifaunal subregions as the operating geographical units (OGUs. The four AOEs are the Qinghai-Zangnan Subregion, the Southwest Mountainous Subregion, the Hainan Subregion and the Taiwan Subregion. Cladistic analysis of subregions generally supports the division of China’s avifauna into Palaearctic and Oriental realms. Two PAE area trees were produced from two different distribution datasets (year 1976 and 2007. The 1976 topology has four distinct subregional branches; however, the 2007 topology has three distinct branches. Moreover, three Palaearctic subregions in the 1976 tree clustered together with the Oriental subregions in the 2007 tree. Such topological differences may reflect changes in the distribution of bird species through circa three decades.
Seo, M.; Watanabe, H.; Nakamura, M.; Sasaki, T.; Ogura, T.; Yahagi, T.; Takahashi, Y.; Ishibashi, J.; Kojima, S.
Deep-sea hydrothermal vents are scientifically interesting environments where strong interactions of geology, chemistry, and biology can be observed. The hydrothermal vents are geologically controlled in association with magmatic activities while diversity of chemicals (such as hydrogen sulfide) contained in hydrothermal fluid is controlled by geochemical interaction between heated seawater and surrounding rocks. In addition to those geological and chemical characters of hydrothermal vents, high biomasses of chemosynthetic community have been known around many vents since the first discovery in the 1970s. To understand the unique system and diversity of biological communities associated with vents is highly valuable in geological, chemical, and biological sciences. As an activity of the research project "TAIGA (Trans-crustal Advection & In-situ bio-geochemical processes of Global sub-seafloor Aquifer)" (Representative: Tetsuro Urabe, Department of Earth & Planetary Science, the University of Tokyo), we analyzed population structures and connectivity as well as larval ecology of various hydrothermal vent species in the Okinawa Trough and the Mariana Trough in an attempt to estimate faunal transitional history associated with hydrothermal activities. The specimens analyzed in the present study were collected by R/V Yokosuka with manned submersible Shinkai6500 and R/V Natsushima with ROV Hyper-Dolphin during YK10-11 and NT11-20 cruises, respectively. In the Mariana Trough (YK10-11), benthic and planktonic faunas were investigated by multiple sampling and use of plankton samplers in three hydrothermal vents (Snail, Archaean, and Urashima-Pika fields). Faunal compositions were then compared as well as size compositions and genetic diversities of major vent species among local populations. In the Okinawa Trough (NT11-20), multiple quantitative sampling was made with simultaneous environmental measurements at more than two sites in five hydrothermal vents (Minami-Ensei Knoll, Yoron Knoll, Izena Hole, Irabu Knoll, and Hatoma Knoll). Among the local populations, biodiversities were analyzed and compared in consideration of abiotic environmental factors including temperature and chemical compositions. Ecological aspects of larvae were examined by laboratory experiments in addition to the genetic approaches and population dynamics. Preliminary results of the ongoing studies suggested that the biodiversity of vents may be consistent with geographical history. By accumulating results of diversified approaches, we progress our study to reveal not only biological characters but also geological and chemical aspects of those hydrothermal vents.
Arantes, Thales Domingos; Theodoro, Raquel Cordeiro; Teixeira, Marcus de Melo; Bosco, Sandra de Moraes Gimenes; Bagagli, Eduardo
Background Paracoccidioides brasiliensis and Paracoccidioides lutzii are the etiological agents of Paracoccidioidomycosis (PCM), and are easily isolated from human patients. However, due to human migration and a long latency period, clinical isolates do not reflect the spatial distribution of these pathogens. Molecular detection of P. brasiliensis and P. lutzii from soil, as well as their isolation from wild animals such as armadillos, are important for monitoring their environmental and geographical distribution. This study aimed to detect and, for the first time, evaluate the genetic diversity of P. brasiliensis and P. lutzii for Paracoccidioidomycosis in endemic and non-endemic areas of the environment, by using Nested PCR and in situ hybridization techniques. Methods/Principal Findings Aerosol (n = 16) and soil (n = 34) samples from armadillo burrows, as well as armadillos (n = 7) were collected in endemic and non-endemic areas of PCM in the Southeastern, Midwestern and Northern regions of Brazil. Both P. brasiliensis and P. lutzii were detected in soil (67.5%) and aerosols (81%) by PCR of Internal Transcribed Spacer (ITS) region (60%), and also by in situ hybridization (83%). Fungal isolation from armadillo tissues was not possible. Sequences from both species of P. brasiliensis and P. lutzii were detected in all regions. In addition, we identified genetic Paracoccidioides variants in soil and aerosol samples which have never been reported before in clinical or armadillo samples, suggesting greater genetic variability in the environment than in vertebrate hosts. Conclusions/Significance Data may reflect the actual occurrence of Paracoccidioides species in their saprobic habitat, despite their absence/non-detection in seven armadillos evaluated in regions with high prevalence of PCM infection by P. lutzii. These results may indicate a possible ecological difference between P. brasiliensis and P. lutzii concerning their wild hosts. PMID:27045486
Tavares, Erika Sendra; Baker, Allan J; Pereira, Sérgio Luiz; Miyaki, Cristina Yumi
Previous hypotheses of phylogenetic relationships among Neotropical parrots were based on limited taxon sampling and lacked support for most internal nodes. In this study we increased the number of taxa (29 species belonging to 25 of the 30 genera) and gene sequences (6388 base pairs of RAG-1, cyt b, NADH2, ATPase 6, ATPase 8, COIII, 12S rDNA, and 16S rDNA) to obtain a stronger molecular phylogenetic hypothesis for this group of birds. Analyses of the combined gene sequences using maximum likelihood and Bayesian methods resulted in a well-supported phylogeny and indicated that amazons and allies are a sister clade to macaws, conures, and relatives, and these two clades are in turn a sister group to parrotlets. Key morphological and behavioral characters used in previous classifications were mapped on the molecular tree and were phylogenetically uninformative. We estimated divergence times of taxa using the molecular tree and Bayesian and penalized likelihood methods that allow for rate variation in DNA substitutions among sites and taxa. Our estimates suggest that the Neotropical parrots shared a common ancestor with Australian parrots 59 Mya (million of years ago; 95% credibility interval (CrI) 66, 51 Mya), well before Australia separated from Antarctica and South America, implying that ancestral parrots were widespread in Gondwanaland. Thus, the divergence of Australian and Neotropical parrots could be attributed to vicariance. The three major clades of Neotropical parrots originated about 50 Mya (95% CrI 57, 41 Mya), coinciding with periods of higher sea level when both Antarctica and South America were fragmented with transcontinental seaways, and likely isolated the ancestors of modern Neotropical parrots in different regions in these continents. The correspondence between major paleoenvironmental changes in South America and the diversification of genera in the clade of amazons and allies between 46 and 16 Mya suggests they diversified exclusively in South America. Conversely, ancestors of parrotlets and of macaws, conures, and allies may have been isolated in Antarctica and/or the southern cone of South America, and only dispersed out of these southern regions when climate cooled and Antarctica became ice-encrusted about 35 Mya. The subsequent radiation of macaws and their allies in South America beginning about 28 Mya (95% CrI 22, 35 Mya) coincides with the uplift of the Andes and the subsequent formation of dry, open grassland habitats that would have facilitated ecological speciation via niche expansion from forested habitats. PMID:16861209
Ho, Adeljean L F C; Pruett, Christin L; Lin, Junda
Poeciliids are a diverse group of small Neotropical fishes, and despite considerable research attention as models in ecology and evolutionary biology, our understanding of their biogeographic and phylogenetic relationships is still limited. We investigated the phylogenetic relationships of South and Central American Poecilia, by examining 2395 base pairs of mitochondrial DNA (ATPase 8/6, COI) and nuclear DNA (S7) for 18 species across six subgenera. Fifty-eight novel sequences were acquired from newly collected specimens and 20 sequences were obtained from previously published material. Analyses of concatenated and partitioned mitochondrial DNA and nuclear DNA sets resulted in a well-supported phylogeny that resolved several monophyletic groups corresponding to previously hypothesized subgenera and species complexes. A divergence-dating analysis supported the hypothesis of the genus Poecilia dispersing into Central America in the early Pliocene (ancestors of Psychropoecilia+Allopoecilia+Mollienesia: 7.3-2.0Mya) from predominantly South America. Subsequently, one lineage (subgenus Allopoecilia: 5.1-1.3Mya) expanded deeper into South America from Lower-Central America, and one lineage expanded from Nuclear-Central America into South America (subgenus Mollienesia: 0.71-0.14Mya). The subgenus Mollienesia diverged into three monophyletic groups that can be identified by nuptial male dorsal fin morphology and inner jaw dentition. A subclade of the unicuspid short-fins (subgenus Mollienesia) was the lineage that expanded into South America during the middle Pleistocene. Species in this subclade are now distributed across northern South America, where they are partially sympatric with Allopoecilia. However the P. (A.) caucana complex was not monophyletic, with P. (A.) wandae clustering in the Mollienesia subclade that expanded into South America. It is apparent that characters (body size, scale count, pigmentation, and gonopodium morphology) used to define the P. (A.) caucana complex are homoplastic and suggestive of rapid convergence in northern South America. Our improved taxon sampling and divergence-time calibration allowed for insights into the timing and direction of dispersals, and provides an improved understanding of the biogeographic history of an enigmatic group of fishes. Furthermore, we provided strong evidence for the monophyly of the subgenus Mollienesia and further substantiated its species complexes; therefore, we advise a taxonomic re-evaluation for the P. (A.) caucana complex to maintain monophyly of both Mollienesia and Allopoecilia. PMID:27129899
Hermant, M.; Prinzing, A.; Vernon, P.; Convey, P.; Hennion, F.
Keywords: Abiotic environmental gradients; endemism level; functional biogeography; island biogeography; Kerguelen Islands; life-history traits; multi-species comparison; phenotypic integration; range size; sub-Antarctic Abstract Aim: Why are some species geographically restricted? Ecological explan
Full Text Available Our review recognizes 15 species of the integripennis species group of Geocharidius from Nuclear Central America, include three species previously described (G. gimlii Erwin, G. integripennis (Bates and G. zullinii Vigna Taglianti and 12 described here as new. They are: G. andersoni sp. n. (type locality: Chiapas, Chiapas Highlands, Cerro Huitepec and G. vignatagliantii sp. n. (type locality: Chiapas, Motozintla, Sierra Madre de Chiapas, Benito Juárez from Mexico; G. antigua sp. n. (type locality: Sacatepéquez, 5 km SE of Antigua, G. balini sp. n. (type locality: Suchitepéquez, 4 km S of Volcan Atitlán, G. erwini sp. n. (type locality: Quiché Department, 7 km NE of Los Encuentros, G. jalapensis sp. n. (type locality: Jalapa Department, 4 km E of Mataquescuintla, G. longinoi, sp. n. (type locality: El Progreso Department, Cerro Pinalón, and G. minimus sp. n. (type locality: Sacatepéquez Department, 5 km SE of Antigua from Guatemala; and G. celaquensis sp. n. (type locality: Lempira Department, Celaque National Park, G. comayaguanus sp. n. (type locality: Comayagua Department, 18 km ENE of Comayagua, G. disjunctus sp. n. (type locality: Francisco Morazán, La Tigra National Park, and G. lencanus sp. n. (type locality: Lempira Department, Celaque National Park from Honduras. For all members of the group, adult structural characters, including male and female genitalia, are described, and a taxonomic key for all members of the integripennis species group is presented based on these characters. Behavioral and biogeographical aspects of speciation in the group are discussed, based on the morphological analysis. In all cases of sympatry, pairs of closely related species show greater differences in sizes than pairs of more remotely related species. Integripennis group species occupy six different montane areas at elevations above 1300m, with no species shared among them. Major faunal barriers in the region limiting present species distributions include the Motagua Fault Zone and a gap between the Guatemalan Cordillera volcanic chain and the Honduran Interior Highlands no higher than 900m in elevation. Highest species diversity is in the Guatematan Cordillera (six species, second highest in the Honduran Interior Highlands area (four species.
Sokolov, Igor M; Kavanaugh, David H
Our review recognizes 15 species of the integripennis species group of Geocharidius from Nuclear Central America, include three species previously described (Geocharidiusgimlii Erwin, Geocharidiusintegripennis (Bates) and Geocharidiuszullinii Vigna Taglianti) and 12 described here as new. They are: Geocharidiusandersoni sp. n. (type locality: Chiapas, Chiapas Highlands, Cerro Huitepec) and Geocharidiusvignatagliantii sp. n. (type locality: Chiapas, Motozintla, Sierra Madre de Chiapas, Benito Juárez) from Mexico; Geocharidiusantigua sp. n. (type locality: Sacatepéquez, 5 km SE of Antigua), Geocharidiusbalini sp. n. (type locality: Suchitepéquez, 4 km S of Volcan Atitlán), Geocharidiuserwini sp. n. (type locality: Quiché Department, 7 km NE of Los Encuentros), Geocharidiusjalapensis sp. n. (type locality: Jalapa Department, 4 km E of Mataquescuintla), Geocharidiuslonginoi, sp. n. (type locality: El Progreso Department, Cerro Pinalón), and Geocharidiusminimus sp. n. (type locality: Sacatepéquez Department, 5 km SE of Antigua) from Guatemala; and Geocharidiuscelaquensis sp. n. (type locality: Lempira Department, Celaque National Park), Geocharidiuscomayaguanus sp. n. (type locality: Comayagua Department, 18 km ENE of Comayagua), Geocharidiusdisjunctus sp. n. (type locality: Francisco Morazán, La Tigra National Park), and Geocharidiuslencanus sp. n. (type locality: Lempira Department, Celaque National Park) from Honduras. For all members of the group, adult structural characters, including male and female genitalia, are described, and a taxonomic key for all members of the integripennis species group is presented based on these characters. Behavioral and biogeographical aspects of speciation in the group are discussed, based on the morphological analysis. In all cases of sympatry, pairs of closely related species show greater differences in sizes than pairs of more remotely related species. Integripennis group species occupy six different montane areas at elevations above 1300m, with no species shared among them. Major faunal barriers in the region limiting present species distributions include the Motagua Fault Zone and a gap between the Guatemalan Cordillera volcanic chain and the Honduran Interior Highlands no higher than 900m in elevation. Highest species diversity is in the Guatematan Cordillera (six species), second highest in the Honduran Interior Highlands area (four species). PMID:25349497
Full Text Available Abstract Background The tendency of animals and plants to independently develop similar features under similar evolutionary pressures - convergence - is a widespread phenomenon in nature. In plants, convergence has been suggested to explain the striking similarity in life form between the giant lobelioids (Campanulaceae, the bellflower family of Africa and the Hawaiian Islands. Under this assumption these plants would have developed the giant habit from herbaceous ancestors independently, in much the same way as has been suggested for the giant senecios of Africa and the silversword alliance of Hawaii. Results Phylogenetic analyses based on plastid (rbcL, trnL-F and nuclear (internal transcribed spacer [ITS] DNA sequences for 101 species in subfamily Lobelioideae demonstrate that the large lobelioids from eastern Africa the Hawaiian Islands, and also South America, French Polynesia and southeast Asia, form a strongly supported monophyletic group. Ancestral state reconstructions of life form and distribution, taking into account phylogenetic uncertainty, indicate their descent from a woody ancestor that was probably confined to Africa. Molecular dating analyses using Penalized Likelihood and Bayesian relaxed clock approaches, and combining multiple calibration points, estimate their first diversification at ~25-33 million years ago (Ma, shortly followed by several long-distance dispersal events that resulted in the current pantropical distribution. Conclusion These results confidently show that lobelioid species, commonly called 'giant', are very closely related and have not developed their giant form from herbaceous ancestors independently. This study, which includes the hitherto largest taxon sampling for subfamily Lobelioideae, highlights the need for a broad phylogenetic framework for testing assumptions about morphological development in general, and convergent evolution in particular.
Mavrodiev, Evgeny V; Laktionov, Alexy P; Cellinese, Nico
The evolution of the diverse flora in the Lower Volga Valley (LVV) (southwest Russia) is complex due to the composite geomorphology and tectonic history of the Caspian Sea and adjacent areas. In the absence of phylogenetic studies and temporal information, we implemented a maximum likelihood (ML) approach and stochastic character mapping reconstruction aiming at recovering historical signals from species occurrence data. A taxon-area matrix of 13 floristic areas and 1018 extant species was constructed and analyzed with RAxML and Mesquite. Additionally, we simulated scenarios with numbers of hypothetical extinct taxa from an unknown palaeoflora that occupied the areas before the dramatic transgression and regression events that have occurred from the Pleistocene to the present day. The flora occurring strictly along the river valley and delta appear to be younger than that of adjacent steppes and desert-like regions, regardless of the chronology of transgression and regression events that led to the geomorphological formation of the LVV. This result is also supported when hypothetical extinct taxa are included in the analyses. The history of each species was inferred by using a stochastic character mapping reconstruction method as implemented in Mesquite. Individual histories appear to be independent from one another and have been shaped by repeated dispersal and extinction events. These reconstructions provide testable hypotheses for more in-depth investigations of their population structure and dynamics. PMID:22957179
Cáceres González, Daniel
Die Bromeliaceae umfassen mehr als 3.100 fast ausschließlich neotropische Arten. Bekannt für ihre außergewöhnliche ökologische Vielseitigkeit haben sich Bromelien erfolgreich in terrestrischen und epiphytischen Lebensräumen ausgebreitet. Eine umfassende Untersuchung des Gefährdungsgrades aller Bromelienarten Panamas und Costa Ricas stand bisher noch aus und ist insbesondere aufgrund des großen Reichtums an Lebensräumen, der beide Länder auszeichnet, und den vielfältigen Veränderungen gebot...
Numerical taxonomy converts the record of characters into digital, and then by similarity analysis expresses genetic relationship in entomology.%数量分类学(numerical taxonomy)把全部性状状态的记录都改换成数值通过相似性分析来描述昆虫学中的亲缘关系.
In this short note I have tried to make clear the issues surrounding a recent discussion on changing-radius paleobiogeographical problems of the Pacific Ocean biotic distribution. It is stressed that such an important discussion cannot be developed in the absence of proper cartographic methods that must necessarily introduce an increasing radius parameter, highlighting the effects of a changing curvature in the continental/oceanic plates in their movements from a globe of ...
Scalera, G.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma1, Roma, Italia
In this short note I have tried to make clear the issues surrounding a recent discussion on changing-radius paleobiogeographical problems of the Pacific Ocean biotic distribution. It is stressed that such an important discussion cannot be developed in the absence of proper cartographic methods that must necessarily introduce an increasing radius parameter, highlighting the effects of a changing curvature in the continental/oceanic plates in their movements from a globe of a given ...
Chen-Yang LIAO; Stephen R.DOWNIE; Yan YU; Xing-Jin HE
Biogeographical patterns and diversification processes of Asia-centered angiosperm groups have been significantly affected by the multistage uplift of the Himalayas-Tibetan Plateau since the Late Tertiary.The divergence time of the largely East Asian Angelica group (Apiaceae,subfamily Apioideae,tribe Selineae) was initially analyzed using BEAST and nrDNA internal transcribed spacer sequence data from 96 representatives of tribe Selineae and relatives.Further analyses of the biogeographical history of the Angelica group were carried out using BEAST,S-DIVA,RASP,and LAGRANGE on datasets containing all or some of the following loci:nrDNA internal and external transcribed spacers; cpDNA rps16 intron; and cpDNA rps16-trnK,rpl32-trnL,and trnL-trnT intergenic spacers.The results suggested that the Angelica group was originally present in the East Palearctic during the global cooling of the late Middle Miocene (13.6 Mya) and that the Angelica s.s.clade originated in the same region at 10.2Mya.Subsequent diversifications of the Angelica s.s.clade intensified in the East Palearctic during the middle Late Miocene (10.0-7.0 Mya) and in the eastern Himalayan Zone during the late Pliocene and Pleistocene (＜4.0Mya).These diversifications likely corresponded with plateau uplift-driven climatic changes.Considering elevational reconstructions,the differential responses to altitude appear to be the primary factor explaining the recent radiation of the group in the eastern Himalayas.The North American species of the Angelica group were retrieved as polyphyletic and their migrations involved six independent dispersals to North America at least since the middle Late Miocene,including four times from northeast Asia and twice from Europe.
Morard, Raphaël; Darling, Kate F; Mahé, Frédéric; Audic, Stéphane; Ujiié, Yurika; Weiner, Agnes K M; André, Aurore; Seears, Heidi A; Wade, Christopher M; Quillévéré, Frédéric; Douady, Christophe J; Escarguel, Gilles; de Garidel-Thoron, Thibault; Siccha, Michael; Kucera, Michal; de Vargas, Colomban
Planktonic foraminifera (Rhizaria) are ubiquitous marine pelagic protists producing calcareous shells with conspicuous morphology. They play an important role in the marine carbon cycle, and their exceptional fossil record serves as the basis for biochronostratigraphy and past climate reconstructions. A major worldwide sampling effort over the last two decades has resulted in the establishment of multiple large collections of cryopreserved individual planktonic foraminifera samples. Thousands of 18S rDNA partial sequences have been generated, representing all major known morphological taxa across their worldwide oceanic range. This comprehensive data coverage provides an opportunity to assess patterns of molecular ecology and evolution in a holistic way for an entire group of planktonic protists. We combined all available published and unpublished genetic data to build PFR(2), the Planktonic foraminifera Ribosomal Reference database. The first version of the database includes 3322 reference 18S rDNA sequences belonging to 32 of the 47 known morphospecies of extant planktonic foraminifera, collected from 460 oceanic stations. All sequences have been rigorously taxonomically curated using a six-rank annotation system fully resolved to the morphological species level and linked to a series of metadata. The PFR(2) website, available at http://pfr2.sb-roscoff.fr, allows downloading the entire database or specific sections, as well as the identification of new planktonic foraminiferal sequences. Its novel, fully documented curation process integrates advances in morphological and molecular taxonomy. It allows for an increase in its taxonomic resolution and assures that integrity is maintained by including a complete contingency tracking of annotations and assuring that the annotations remain internally consistent. PMID:25828689
Meliponini neotropicais: o gênero Partamona Schwarz, 1939 (Hymenoptera, Apidae, Apinae - bionomia e biogeografia Neotropical Meliponini: the genus Partamona Schwarz, 1939 (Hymenoptera, Apidae, Apinae - bionomy and biogeography
João M. F. Camargo
Full Text Available This work, dedicated to the study of nesting habits of the species of the Neotropical genus Partamona Schwarz, is a sequence to the taxonomic revision recently published elsewhere. A total of 214 nests and nest aggregations of 18 species [Partamona epiphytophila Pedro & Camargo, 2003; P. testacea (Klug, 1807; P. mourei Camargo, 1980; P. vicina Camargo, 1980; P. auripennis Pedro & Camargo, 2003; P. combinata Pedro & Camargo, 2003; P. chapadicola Pedro & Camargo, 2003; P. nhambiquara Pedro & Camargo, 2003; P. ferreirai Pedro & Camargo, 2003; P. pearsoni (Schwarz, 1938; P. gregaria Pedro & Camargo, 2003; P. batesi Pedro & Camargo, 2003; P. ailyae Camargo, 1980; P. cupira (Smith, 1863; P. mulata Moure in Camargo, 1980; P. seridoensis Pedro & Camargo, 2003; P. criptica Pedro & Camargo, 2003; P. helleri (Friese, 1900] were studied , including data about habitat, substrate, structural characteristics, construction materials and behavior. The descriptions of the nests are illustrated with 48 drawings. Partial data of the nests of P. bilineata (Say, 1837, P. xanthogastra Pedro & Camargo, 1997, P. orizabaensis (Strand, 1919, P. peckolti (Friese, 1901, P. aequatoriana Camargo, 1980, P. musarum (Cockerell, 1917 and P. rustica Pedro & Camargo, 2003 are also presented. Nests of P. grandipennis (Schwarz, 1951, P. yungarum Pedro & Camargo, 2003, P. subtilis Pedro & Camargo, 2003, P. vitae Pedro & Camargo, 2003, P. nigrior (Cockerell, 1925, P. sooretamae Pedro & Camargo, 2003 and P. littoralis Pedro & Camargo, 2003 are unknown. The species of Partamona build notable nest entrance structures, with special surfaces for incoming / exiting bees; some of them are extremely well-elaborated and ornamented, serving as flight orientation targets. All species endemic to western Ecuador to Mexico with known nesting habits (P. orizabaensis, P. peckolti, P. xanthogastra, P. bilineata, P. aequatoriana and P. musarum build their nests in several substrates, non-associated with termitaria, such as cavities and crevices in walls, among roots of epiphytes and in bases of palm leaves, in abandoned bird nests, under bridges, and in other protected places, except P. peckolti that occasionally occupies termite nests. In South America, on the eastern side of the Andes, only P. epiphytophila and P. helleri nest among roots of epiphytes and other substrates, non-associated with termitaria. All other species studied (P. batesi, P. gregaria, P. pearsoni, P. ferreirai, P. chapadicola, P. nhambiquara, P. vicina, P. mourei, P. auripennis, P. combinata, P. cupira, P. mulata, P. ailyae, P. seridoensis, P. criptica and P. rustica nest inside active termite nests, whether epigeous or arboreous. The only species that builds obligate subterranean nests, associated or not with termite or ant nests (Atta spp. is P. testacea. Nests of Partamona have one vestibular chamber (autapomorphic for the genus closely adjacent to the entrance, filled with a labyrinth of anastomosing pillars and connectives, made of earth and resins. One principal chamber exists for food and brood, but in some species one or more additional chambers are filled with food storage pots. In nests of P. vicina, there is one atrium or "false nest", between the vestibule and the brood chamber, which contains involucral sheaths, cells and empty pots. All structures of the nest are supported by permanent pillars made of earth and resins (another autapomorphy of the genus. The characters concerning nesting habits were coded and combined with morphological and biogeographic data, in order to hypothesize the evolutive scenario of the genus using cladistic methodology. The phylogenetic hypothesis presented is the following: (((((P. bilineata (P. grandipennis, P. xanthogastra (P. orizabaensis, P. peckolti (P. aequatoriana, P. musarum P. epiphytophila, P. yungarum, P. subtilis, P. vitae (((((P. testacea (P. mourei, P. vicina (P. nigrior (P. auripennis, P. combinata (P. ferreirai (P. pearsoni (P. gregaria (P. batesi (P. chapadicola, P. nhambiquara ((((P. ailyae, P. sooretamae P. cupira, P. mulata P. seridoensis P. criptica, P. rustica, P. littoralis P. helleri. One area cladogram is presented. Dates of some vicariance / cladogenesis events are suggested. For bilineata / epiphytophila group, which inhabits the Southwestern Amazonia and the Chocó-Mexican biogeographical components, the origin of ancestral species is attributed to the Middle Miocene, when the transgressions of the Maracaibo and Paranense seas isolated the tropical northwestern South America from the eastern continental land mass. The next cladogenic event in the history of the bilineata / epiphytophila group is attributed to the Plio-Pleistocene, when the Ecuadorian Andes reached more than 3000 m, and the ancestral species was fragmented in two populations, one occupying the western Andes (ancestral species of the bilineata subgroup and other the southwestern Amazon (ancestral species of the epiphytophila subgroup. Other aspects of the history of Partamona are also discussed.
Cisneros-Heredia, D.F.; McDiarmid, R.W.
We describe a new species of Glassfrog, Centrolene mariaelenae n. sp., from the Contrafuerte de Tzunantza, southeastern Ecuador. The new species is assigned to the Centrolene gorzulai species group, a clade previously known only from the Guayana Shield region, because the parietal peritoneum is transparent and the hepatic peritoneum is covered by guanophores. We analyze the diversity patterns of Glassfrogs from eastern Ecuador. The distribution of the new species herein described supports previous hypothesis of a biogeographical connection between the Andes and the Guayana Shield for various groups of plants and animals; particularly a relationship between the Guayana Shield and the sandstone outcrops mountain ranges of southeastern Ecuador and northeastern Peru. We also comment on the infrageneric and generic classification of Glassfrogs, and propose the new combinations Centrolene balionotum n. comb., Cochranella antisthenesi n. comb., and Cochranella pulverata n. comb.
A. A. Heidari
Full Text Available Earthquake can pose earth-shattering health hazards to the natural slops and land infrastructures. One of the chief consequences of the earthquakes can be land sliding, which is instigated by durable shaking. In this research, an efficient procedure is proposed to assist the prediction of earthquake-originated slope displacements (EIDS. New hybrid SVM-CBBO strategy is implemented to predict the EIDS. For this purpose, first, chaos paradigm is combined with initialization of BBO to enhance the diversification and intensification capacity of the conventional BBO optimizer. Then, chaotic BBO is developed as the searching scheme to investigate the best values of SVR parameters. In this paper, it will be confirmed that how the new computing approach is effective in prediction of EIDS. The outcomes affirm that the SVR-BBO strategy with chaos can be employed effectively as a predicting tool for evaluating the EIDS.
National Oceanic and Atmospheric Administration, Department of Commerce — This dataset represents relative seabird abundance predictions from spatial models developed for the New York offshore spatial planning area. This raster was...
Austin, Jeremy J; Arnold, E Nicholas; Bour, Roger
A radiation of five species of giant tortoises (Cylindraspis) existed in the southwest Indian Ocean, on the Mascarene islands, and another (of Aldabrachelys) has been postulated on small islands north of Madagascar, from where at least eight nominal species have been named and up to five have been recently recognized. Of 37 specimens of Madagascan and small-island Aldabrachelys investigated by us, 23 yielded significant portions of a 428-base-pair (bp) fragment of mitochondrial (cytochrome b and tRNA-Glu), including type material of seven nominal species (A. arnoldi, A. dussumieri, A. hololissa, A. daudinii, A. sumierei, A. ponderosa and A. gouffei). These and nearly all the remaining specimens, including 15 additional captive individuals sequenced previously, show little variation. Thirty-three exhibit no differences and the remainder diverge by only 1-4 bp (0.23-0.93%). This contrasts with more widely accepted tortoise species which show much greater inter- and intraspecific differences. The non-Madagascan material examined may therefore only represent a single species and all specimens may come from Aldabra where the common haplotype is known to occur. The present study provides no evidence against the Madagascan origin for Aldabra tortoises suggested by a previous molecular phylogenetic analysis, the direction of marine currents and phylogeography of other reptiles in the area. Ancient mitochondrial DNA from the extinct subfossil A. grandidieri of Madagascar differs at 25 sites (5.8%) from all other Aldabrachelys samples examined here. PMID:12755871
Portik, Daniel M; Papenfuss, Theodore J.
Background The Arabian Peninsula is home to a unique fauna that has assembled and evolved throughout the course of major geophysical events, including the separation of the Arabian Plate from Africa and subsequent collision with Eurasia. Opportunities for faunal exchanges with particular continents occurred in temporally distinct periods, and the presence of African, Western Eurasian, and South Asian derived taxa on the Arabian Peninsula signifies the complexity of these historical biogeograp...
Mara Rejane Ritter
Full Text Available A distribuição geográfica das 39 espécies nativas de Mikania Willd. no Rio Grande do Sul foi estudada em duas escalas: uma escala regional, utilizando regiões fisiográficas como unidades, e uma escala continental, considerando regiões político-geográficas como unidades. A riqueza específica e a amplitude de distribuiçãoforam obtidas diretamente de matrizes de presença e ausência, relacionando espécies e regiões. A matriz regional foi analisada por dois métodos multivariados, uma análise de agrupamentos e uma análise de coordenadas principais, utilizando o complemento do coeficiente de Jaccard como elemento de comparação (dissimilaridade. Na escala regional as regiões mais ricas foram o Litoral e a Depressão Central, enquanto na escala continental, a maioria das espécies sul-rio-grandenses foram também encontradas no Sudeste do Brasil e no Sul da América do Sul. A análise multivariada evidenciou dois grupos principais no Estado, um oriental e outro ocidental. Em cada um desses grupos foram evidenciados dois subgrupos relacionados a características climáticas e geológicas do Estado.Os padrões de distribuição de Mikania confirmam o caráter tropical do gênero e as principais rotas de migração descritas para a flora do Sul do Brasil.The geographical distribution of the 39 species of Mikania Willd. native in Rio Grande do Sul was studied at two scales: a state-regional scale, using physiographic regions as units, and an american-continental scale, considering politic-geographic regions as units. Specific richness and distribution amplitude were obtained directly from presence and absence matrixes, relating species and regions. The state-regional matrix was also analysed by two multivariate methods, a cluster analysis and a principal coordinate analysis, using the complement of the Jaccard coefficient as a measure of dissimilarity. At the state-regional scale, the richest regions were the Coastal Plain and the Central Depression, whereas at the american-continental scale, most of the South Riograndean species were also found in Southeastern Brazil and Southern South America. The multivariate analysis evidenced two main groups in Rio Grande do Sul, one eastern and another western. Within each of these groups, two subgroups related to climatic and geological features were evidenced. The distribution patterns of Mikania confirm the tropical character of the genus, and the main migration routes described for the southern Brazilian vascular flora.
Luiz A. Campos
Full Text Available Neste trabalho foi realizada uma análise cladística, utilizando 63 caracteres, dos 30 gêneros da tribo Neotropical Ochlerini Rolston, no intuito de testar seu monofiletismo e estabelecer uma hipótese de parentesco. Janeirona Distant, 1911 (Pentatomini e as tribos Discocephalini e Halyini foram incluídas no grupo-interno para testar seu relacionamento com Ochlerini; Marghita Ruckes, 1964 e Stictochilus Bergroth, 1918 (Pentatomini foram utilizados como grupos-externos. Os cladogramas de consenso estrito obtidos indicam que Ochlerini e Discocephalinae são grupos monofiléticos, mas Pentatominae, Halyini+Ochlerini, Pentatomini+Ochlerini, Ochlerus Spinola, 1837, Stalius Rolston, 1992 e Alitocoris Sailer, 1950 são grupos merofiléticos. Discocephalini e Ochlerini compartilham três sinapomorfias: primeiro segmento do rostro longo, alcançando o prosterno; metasterno carenado longitudinalmente; e superfície dorsal do segmento X do macho membranosa no terço basal. Ochlerini é sustentada por uma sinapomorfia, a superfície dorsal do terceiro artículo metatarsal das fêmeas aplainada. Uma análise biogeográfica a partir dos cladogramas de consenso mostrou padrões congruentes com eventos vicariantes propostos para a região Neotropical.A cladistic analysis using 63 characters and 30 genera of the Neotropical tribe Ochlerini Rolston was performed to test their monophyletic condition and to establish a relationship hypothesis. Janeirona Distant, 1911 (Pentatomini and the tribes Discocephalini and Halyini were included in the ingroup to test their relationship with Ochlerini; Marghita Ruckes, 1964 and Stictochilus Bergroth, 1918 (Pentatomini were used as outgroups. The obtained strict consensus cladograms indicate that Ochlerini and Discocephalinae are monophyletic groups, but Pentatominae, Halyini+Ochlerini, Pentatomini+Ochlerini, Ochlerus Spinola, 1837, Stalius Rolston, 1992 and Alitocoris Sailer, 1950 are merophyletic groups. Discocephalini and Ochlerini share three synapomorphies: first rostral segment long, attaining prosternum; metasternum with a mesial, longitudinal carina, and dorsal surface of basal third of male proctiger membranous. Ochlerini is supported by one synapomorphy, the flattened dorsal surface of third tarsal segment of hind legs, in females. Biogeographical analysis based on consensus cladograms shows congruent patterns with several vicariant events proposed for the Neotropical region.