A. Townsend Peterson

Bio: A. Townsend Peterson is an academic researcher from University of Kansas. The author has contributed to research in topics: Environmental niche modelling & Ecological niche. The author has an hindex of 91, co-authored 521 publications receiving 51524 citations. Previous affiliations of A. Townsend Peterson include California Academy of Sciences & University of Chicago.

The climate envelope may not be empty

Abstract: A recent paper (1) purported to document negligible climatic determination among European bird species, with implications for forecasting range shifts in changing climates. However, only 12 of 100 species analyzed were endemic—thus, for the remaining 88% of test species, key limits with likely climatic determination were excluded, particularly eastward and southward (2). Second, the authors developed null distributions conserving the same prevalence and semivariogram as real species' distributions and showed that real distributions were not modeled better than “null” distributions. However, most variation in null and real distributions at broad geographic scales is explained by spatially structured climate variation that is difficult to disentangle. The authors' manipulation fails to eliminate climate as a correlate of null ranges exactly because their occurrences were spatially clumped: as climate is autocorrelated, null distributions have climate signatures just like real distributions. Producing null models removing effects of climate but keeping the spatial cohesion of the distribution is unlikely, as in recent debates regarding mid-domain effects as appropriate null models for diversity (3). Null distributions will show climate signatures similar to those of real species that are not eliminated in their randomization algorithm, so the authors cannot reject the hypothesis of a climate association in European birds. Nonetheless, we agree that, because distributions can be modeled by using current spatially structured climatic predictors without necessity of direct causal linkages (4), more studies oriented at testing the robustness of correlative methods in predicting species' distributions under future climate scenarios are needed (5).

Are large-scale distributional shifts of the blue-winged macaw (Primolius maracana) related to climate change?

Abstract: Aim To evaluate whether observed geographical shifts in the distribution of the blue-winged macaw (Primolius maracana) are related to ongoing processes of global climate change. This species is vulnerable to extinction and has shown striking range retractions in recent decades, withdrawing broadly from southern portions of its historical distribution. Its range reduction has generally been attributed to the effects of habitat loss; however, as this species has also disappeared from large forested areas, consideration of other factors that may act in concert is merited. Location Historical distribution of the blue-winged macaw in Brazil, eastern Paraguay and northern Argentina. Methods We used a correlative approach to test a hypothesis of causation of observed shifts by reduction of habitable areas mediated by climate change. We developed models of the ecological niche requirements of the blue-winged macaw, based on point-occurrence data and climate scenarios for pre-1950 and post-1950 periods, and tested model predictivity for anticipating geographical distributions within time periods. Then we projected each model to the other time period and compared distributions predicted under both climate scenarios to assess shifts of habitable areas across decades and to evaluate an explanation for observed range retractions. Results Differences between predicted distributions of the blue-winged macaw over the twentieth century were, in general, minor and no change in suitability of landscapes was predicted across large areas of the species’ original range in different time periods. No tendency towards range retraction in the south was predicted, rather conditions in the southern part of the species’ range tended to show improvement for the species. Main conclusions Our test permitted elimination of climate change as a likely explanation for the observed shifts in the distribution of the blue-winged macaw, and points rather to other causal explanations (e.g. changing regional land use, emerging diseases).

Leishmaniasis transmission: distribution and coarse-resolution ecology of two vectors and two parasites in Egypt

Abstract: Introduction: In past decades, leishmaniasis burden has been low across Egypt; however, changing environment and land use has placed several parts of the country at risk. As a consequence, leishmaniasis has become a particularly difficult health problem, both for local inhabitants and for multinational military personnel. Methods: To evaluate coarse-resolution aspects of the ecology of leishmaniasis transmission, collection records for sandflies and Leishmania species were obtained from diverse sources. To characterize environmental variation across the country, we used multitemporal Land Surface Temperature (LST) and Normalized Difference Vegetation Index (NDVI) data from the Moderate Resolution Imaging Spectroradiometer (MODIS) for 2005-2011. Ecological niche models were generated using MaxEnt, and results were analyzed using background similarity tests to assess whether associations among vectors and parasites (i.e., niche similarity) can be detected across broad geographic regions. Results: We found niche similarity only between one vector species and its corresponding parasite species (i.e., Phlebotomus papatasi with Leishmania major), suggesting that geographic ranges of zoonotic cutaneous leishmaniasis and its potential vector may overlap, but under distinct environmental associations. Other associations (e.g., P. sergenti with L. major) were not supported. Mapping suitable areas for each species suggested that northeastern Egypt is particularly at risk because both parasites have potential to circulate. Conclusions: Ecological niche modeling approaches can be used as a first-pass assessment of vector-parasite interactions, offering useful insights into constraints on the geography of transmission patterns of leishmaniasis.

Niche Modeling: Model Evaluation

Abstract: Ecological niche modeling has become a very popular tool in ecological and biogeographic studies across broad extents. The tool is used in hundreds of publications each year now, but some fundamental aspects of the approach have seen a fair amount of carelessness. Among these aspects is that of model evaluation or validation. This unit provides a simple introduction to the basic concepts that are important in model validation, using some very simple examples. The focus is on two solutions to the challenge of model evaluation: a simple cumulative binomial approach that can be used with binary model outputs, and partial ROC analysis, which can be used with continuous model outputs.

Risk mapping of highly pathogenic avian influenza distribution and spread

Abstract: The rapid emergence and spread of highly pathogenic H5N1 avian influenza begs effective and accurate mapping of current knowledge and future risk of infection. Methods for such mapping, however, are rudimentary, and few good examples exist for use as templates for risk-mapping efforts. We review the transmission cycle of avian influenza viruses, and identify points on which risk-mapping can focus. We provide examples from the literature and from our work that illustrate mapping risk based on (1) avian influenza case occurrences, (2) poultry distributions and movements, and (3) migratory bird movements.

The Theory of Island Biogeography

Abstract: Preface to the Princeton Landmarks in Biology Edition vii Preface xi Symbols Used xiii 1. The Importance of Islands 3 2. Area and Number of Speicies 8 3. Further Explanations of the Area-Diversity Pattern 19 4. The Strategy of Colonization 68 5. Invasibility and the Variable Niche 94 6. Stepping Stones and Biotic Exchange 123 7. Evolutionary Changes Following Colonization 145 8. Prospect 181 Glossary 185 References 193 Index 201

Bayesian Phylogenetics with BEAUti and the BEAST 1.7

Abstract: Computational evolutionary biology, statistical phylogenetics and coalescent-based population genetics are becoming increasingly central to the analysis and understanding of molecular sequence data. We present the Bayesian Evolutionary Analysis by Sampling Trees (BEAST) software package version 1.7, which implements a family of Markov chain Monte Carlo (MCMC) algorithms for Bayesian phylogenetic inference, divergence time dating, coalescent analysis, phylogeography and related molecular evolutionary analyses. This package includes an enhanced graphical user interface program called Bayesian Evolutionary Analysis Utility (BEAUti) that enables access to advanced models for molecular sequence and phenotypic trait evolution that were previously available to developers only. The package also provides new tools for visualizing and summarizing multispecies coalescent and phylogeographic analyses. BEAUti and BEAST 1.7 are open source under the GNU lesser general public license and available at http://beast-mcmc.googlecode.com and http://beast.bio.ed.ac.uk

Ecological and Evolutionary Responses to Recent Climate Change

Abstract: Ecological changes in the phenology and distribution of plants and animals are occurring in all well-studied marine, freshwater, and terrestrial groups These observed changes are heavily biased in the directions predicted from global warming and have been linked to local or regional climate change through correlations between climate and biological variation, field and laboratory experiments, and physiological research Range-restricted species, particularly polar and mountaintop species, show severe range contractions and have been the first groups in which entire species have gone extinct due to recent climate change Tropical coral reefs and amphibians have been most negatively affected Predator-prey and plant-insect interactions have been disrupted when interacting species have responded differently to warming Evolutionary adaptations to warmer conditions have occurred in the interiors of species’ ranges, and resource use and dispersal have evolved rapidly at expanding range margins Observed genetic shifts modulate local effects of climate change, but there is little evidence that they will mitigate negative effects at the species level