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Showing papers by "A. Townsend Peterson published in 2014"


Journal ArticleDOI
TL;DR: The importance of capturing the distributional ecology of any species involved in pathogen transmission, defining the environmental conditions required, and the projection of that niche onto geography is demonstrated.

192 citations


Journal ArticleDOI
TL;DR: A novel approach to identifying areas of potential distribution across novel geographic regions that avoids perilious extrapolation into novel environments is explored, finding that changes are best attributed to climatic differences between the two continents.
Abstract: Emerging infectious diseases can present serious threats to wildlife, even to the point of causing extinction. Whitenose fungus (Pseudogymnoascus destructans) is causing an epizootic in bats that is expanding rapidly, both geographically and taxonomically. Little is known of the ecology and distributional potential of this intercontinental pathogen. We address this gap via ecological niche models that characterise coarse resolution niche differences between fungus populations on different continents, identifying areas potentially vulnerable to infection in South America. Here we explore a novel approach to identifying areas of potential distribution across novel geographic regions that avoids perilious extrapolation into novel environments. European and North American fungus populations show differential use of environmental space, but rather than niche differentiation, we find that changes are best attributed to climatic differences between the two continents. Suitable areas for spread of the pathogen were identified across southern South America; however caution should be taken to avoid underestimating the potential for spread of this pathogen in South America.

177 citations


Journal ArticleDOI
TL;DR: Diversification and demographic events appear to have been affected by the Quaternary climatic cycles as a result of isolation in multiple patches of xerophytic vegetation, and these small patches presently harbouring P. aurisetus populations seem to operate as microrefugia, both at present and during Pleistocene interglacial periods.
Abstract: The role of Pleistocene climate changes in promoting evolutionary diversification in global biota is well documented, but the great majority of data regarding this subject come from North America and Europe, which were greatly affected by glaciation. The effects of Pleistocene changes on cold- and/or dry-adapted species in tropical areas where glaciers were not present remain sparsely investigated. Many such species are restricted to small areas surrounded by unfavourable habitats, which may represent potential interglacial microrefugia. Here, we analysed the phylogeographic structure and diversification history of seven cactus species in the Pilosocereus aurisetus complex that are restricted to rocky areas with high diversity and endemism within the Neotropical savannas of eastern South America. We combined palaeodistributional estimates with standard phylogeographic approaches based on two chloroplast DNA regions (trnT-trnL and trnS-trnG), exon 1 of the nuclear gene PhyC and 10 nuclear microsatellite loci. Our analyses revealed a phylogeographic history marked by multiple levels of distributional fragmentation, isolation leading to allopatric differentiation and secondary contact among divergent lineages within the complex. Diversification and demographic events appear to have been affected by the Quaternary climatic cycles as a result of isolation in multiple patches of xerophytic vegetation. These small patches presently harbouring P. aurisetus populations seem to operate as microrefugia, both at present and during Pleistocene interglacial periods; the role of such microrefugia should be explored and analysed in greater detail.

95 citations


Journal ArticleDOI
TL;DR: The list of the birds of Mexico is assembled including all species for which presence, recent or historical, has been confirmed, and incorporating recent taxonomic viewpoints, to obtain numbers of species and taxonomic richness, seasonal status, ecological distribution, and conservation status.
Abstract: Se presenta un analisis del listado actualizado de las aves de Mexico, con enfoques taxonomicos actuales y abarcando todas aquellas especies que tengan registros recientes e historicos de presencia dentro del territorio nacional. Se presenta una sintesis de la riqueza de especies, riqueza taxonomica, estatus estacional, distribucion ecologica, su grado de endemismo y estatus de conservacion, asi como de los patrones geograficos de la riqueza y el endemismo. De las alrededor de 10 500 especies de aves que hay en el mundo, entre 1 123 y 1 150, cerca del 11% del total mundial, habitan en Mexico. Esto coloca a este pais en el onceavo lugar de acuerdo a su riqueza avifaunistica y en el cuarto lugar en proporcion de endemismo entre los paises megadiversos del mundo. El 77% de las especies se reproducen en Mexico y la mayor parte son especies residentes permanentes, seguidas en numero por las visitantes de invierno y las migratorias de paso. Un total de entre 194 y 212 especies son endemicas de Mexico, lo que representa aproximadamente entre el 18 y 20% del total de especies registrado en el pais y entre 298 y 388 especies (26-33%) de la avifauna mexicana se encuentra en alguna categoria de amenaza de acuerdo a autoridades nacionales o internacionales. La mayor concentracion de especies se presenta a lo largo de la vertiente del golfo de Mexico y la peninsula de Yucatan, especialmente siendo mas elevada la riqueza de especies en las zonas de contacto de ambientes montanos y tropicales de tierras bajas, tanto en el golfo como en la vertiente del Pacifico. Los valores altos de la riqueza de especies endemicas y la proporcion de estas se concentran a lo largo del oeste de Mexico, principalmente en las zonas montanas del Eje Neovolcanico, las Sierras Madre Occidental y del Sur, y la planicie costera del Pacifico.

87 citations


Journal ArticleDOI
TL;DR: The authors' models indicate the potential for range expansion of climate suitable for survival of Rhipicephalus (Boophilus) microplus and R. annulatus in the southern United States by mid-century, which increases the risk of reintroduction of these ticks and cattle tick fever into major cattle producing areas.
Abstract: Background: For >100 years cattle production in the southern United States has been threatened by cattle fever. It is caused by an invasive parasite-vector complex that includes the protozoan hemoparasites Babesia bovis and B. bigemina, which are transmitted among domestic cattle via Rhipicephalus tick vectors of the subgenus Boophilus. In 1906 an eradication effort was started and by 1943 Boophilus ticks had been confined to a narrow tick eradication quarantine area (TEQA) along the Texas-Mexico border. However, a dramatic increase in tick infestations in areas outside the TEQA over the last decade suggests these tick vectors may be poised to re-invade the southern United States. We investigated historical and potential future distributions of climatic habitats of cattle fever ticks to assess the potential for a range expansion. Methods: We built robust spatial predictions of habitat suitability for the vector species Rhipicephalus (Boophilus) microplus and R. (B.) annulatus across the southern United States for three time periods: 1906, present day (2012), and 2050. We used analysis of molecular variance (AMOVA) to identify persistent tick occurrences and analysis of bias in the climate proximate to these occurrences to identify key environmental parameters associated with the ecology of both species. We then used ecological niche modeling algorithms GARP and Maxent to construct models that related known occurrences of ticks in the TEQA during 2001–2011 with geospatial data layers that summarized important climate parameters at all three time periods. Results: We identified persistent tick infestations and specific climate parameters that appear to be drivers of ecological niches of the two tick species. Spatial models projected onto climate data representative of climate in 1906 reproduced historical pre-eradication tick distributions. Present-day predictions, although constrained to areas near the TEQA, extrapolated well onto climate projections for 2050. Conclusions: Our models indicate the potential for range expansion of climate suitable for survival of R. microplus and R. annulatus in the southern United States by mid-century, which increases the risk of reintroduction of these ticks and cattle tick fever into major cattle producing areas.

67 citations



Journal ArticleDOI
TL;DR: This study suggests that T. b.
Abstract: Background: The Triatoma brasiliensis complex is a monophyletic group, comprising three species, one of which includes two subspecific taxa, distributed across 12 Brazilian states, in the caatinga and cerrado biomes. Members of the complex are diverse in terms of epidemiological importance, morphology, biology, ecology, and genetics. Triatoma b. brasiliensis is the most disease-relevant member of the complex in terms of epidemiology, extensive distribution, broad feeding preferences, broad ecological distribution, and high rates of infection with Trypanosoma cruzi; consequently, it is considered the principal vector of Chagas disease in northeastern Brazil. Methods: We used ecological niche models to estimate potential distributions of all members of the complex, and evaluated the potential for suitable adjacent areas to be colonized; we also present first evaluations of potential for climate change-mediated distributional shifts. Models were developed using the GARP and Maxent algorithms. Results: Models for three members of the complex (T. b. brasiliensis, N= 332; T. b. macromelasoma, N= 35; and T. juazeirensis, N = 78) had significant distributional predictivity; however, models for T. sherlocki and T. melanica, both with very small sample sizes (N = 7), did not yield predictions that performed better than random. Model projections onto future-climate scenarios indicated little broad-scale potential for change in the potential distribution of the complex through 2050. Conclusions: This study suggests that T. b. brasiliensis is the member of the complex with the greatest distributional potential to colonize new areas: overall; however, the distribution of the complex appears relatively stable. These analyses offer key information to guide proactive monitoring and remediation activities to reduce risk of Chagas disease transmission.

58 citations


Journal ArticleDOI
TL;DR: Whether niche conservatism is a common pattern among vector species of Trypanosoma cruzi that inhabit North and Central America, a highly heterogeneous landmass in terms of environmental gradients, is analyzed and the hypothesis of niche conservatism could not be rejected for any of six sister species pairs.
Abstract: The niche conservatism hypothesis states that related species diverge in niche characteristics at lower rates than expected, given their lineage divergence. Here we analyze whether niche conservatism is a common pattern among vector species (Hemiptera: Reduviidae: Triatominae) of Trypanosoma cruzi that inhabit North and Central America, a highly heterogeneous landmass in terms of environmental gradients. Mitochondrial and nuclear loci were used in a multi-locus phylogenetic framework to reconstruct phylogenetic relationships among species and estimate time of divergence of selected clades to draw biogeographic inferences. Then, we estimated similarity between the ecological niche of sister species and tested the niche conservatism hypothesis using our best estimate of phylogeny. Triatoma is not monophyletic. A primary clade with all North and Central American (NCA) triatomine species from the genera Triatoma, Dipetalogaster, and Panstrongylus, was consistently recovered. Nearctic species within the NCA clade (T. p. protracta, T. r. rubida) diverged during the Pliocene, whereas the Neotropical species (T. phyllosoma, T. longipennis, T. dimidiata complex) are estimated to have diverged more recently, during the Pleistocene. The hypothesis of niche conservatism could not be rejected for any of six sister species pairs. Niche similarity between sister species best fits a retention model. While this framework is used here to infer niche evolution, it has a direct impact on spatial vector dynamics driven by human population movements, expansion of transportation networks and climate change scenarios.

55 citations


Journal ArticleDOI
TL;DR: This study adds to a growing list of studies that support predictions of Haldane’s Rule using cline analysis of multiple loci of differing inheritance modes, although alternate hypotheses like selection on different mtDNA types cannot be ruled out.
Abstract: Haldane’s Rule, the tendency for the heterogametic sex to show reduced fertility in hybrid crosses, can obscure the signal of gene flow in mtDNA between species where females are heterogametic. Therefore, it is important when studying speciation and species limits in female-heterogametic species like birds to assess the signature of gene flow in the nuclear genome as well. We studied introgression of microsatellites and mtDNA across a secondary contact zone between coastal and interior lineages of Western Scrub-Jays (Aphelocoma californica) to test for a signature of Haldane’s Rule: a narrower cline of introgression in mtDNA compared to nuclear markers. Our initial phylogeographic analysis revealed that there is only one major area of contact between coastal and interior lineages and identified five genetic clusters with strong spatial structuring: Pacific Slope, Interior US, Edwards Plateau (Texas), Northern Mexico, and Southern Mexico. Consistent with predictions from Haldane’s Rule, mtDNA showed a narrower cline than nuclear markers across a transect through the hybrid zone. This result is not being driven by female-biased dispersal because neutral diffusion analysis, which included estimates of sex-specific dispersal rates, also showed less diffusion of mtDNA. Lineage-specific plumage traits were associated with nuclear genetic profiles for individuals in the hybrid zone, indicating that these differences are under genetic control. This study adds to a growing list of studies that support predictions of Haldane’s Rule using cline analysis of multiple loci of differing inheritance modes, although alternate hypotheses like selection on different mtDNA types cannot be ruled out. That Haldane’s Rule appears to be operating in this system suggests a measure of reproductive isolation between the Pacific Slope and interior lineages. Based on a variety of evidence from the phenotype, ecology, and genetics, we recommend elevating three lineages to species level: A. californica (Pacific Slope); A. woodhouseii (Interior US plus Edwards Plateau plus Northern Mexico); A. sumichrasti (Southern Mexico). The distinctive Edwards Plateau population in Texas, which was monophyletic in mtDNA except for one individual, should be studied in greater detail given habitat threat.

54 citations


Journal ArticleDOI
25 Jun 2014-PLOS ONE
TL;DR: The results suggest that niche modeling and niche-centroid distance approaches can be used to mapping distributions of environmental suitability for venomous snakes; combining this ecological information with socioeconomic factors may help with inferring potential risk areas for snakebites.
Abstract: CONACYT support the postdoctoral stay of Carlos Yanez-Arenas at the University of Kansas. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

53 citations


Journal ArticleDOI
08 Aug 2014-PLOS ONE
TL;DR: The effects of certainty of diagnosis, oversampling in well-studied region, and error balance on results of mapping exercises are explored; the final, adjusted risk map indicates broad risk areas across much of West Africa.
Abstract: Lassa fever is a disease that has been reported from sites across West Africa; it is caused by an arenavirus that is hosted by the rodent M. natalensis. Although it is confined to West Africa, and has been documented in detail in some well-studied areas, the details of the distribution of risk of Lassa virus infection remain poorly known at the level of the broader region. In this paper, we explored the effects of certainty of diagnosis, oversampling in well-studied region, and error balance on results of mapping exercises. Each of the three factors assessed in this study had clear and consistent influences on model results, overestimating risk in southern, humid zones in West Africa, and underestimating risk in drier and more northern areas. The final, adjusted risk map indicates broad risk areas across much of West Africa. Although risk maps are increasingly easy to develop from disease occurrence data and raster data sets summarizing aspects of environments and landscapes, this process is highly sensitive to issues of data quality, sampling design, and design of analysis, with macrogeographic implications of each of these issues and the potential for misrepresenting real patterns of risk.

Journal ArticleDOI
TL;DR: This study revealed contributions of different environmental factors to mycetoma infection risk, identified suitable environments and regions for transmission, signaled a potential myCetoma-Acacia association, and provided steps towards a robust risk map for the disease.
Abstract: In 2013, the World Health Organization (WHO) recognized mycetoma as one of the neglected tropical conditions due to the efforts of the mycetoma consortium. This same consortium formulated knowledge gaps that require further research. One of these gaps was that very few data are available on the epidemiology and transmission cycle of the causative agents. Previous work suggested a soil-borne or Acacia thorn-prick-mediated origin of mycetoma infections, but no studies have investigated effects of soil type and Acacia geographic distribution on mycetoma case distributions. Here, we map risk of mycetoma infection across Sudan and South Sudan using ecological niche modeling (ENM). For this study, records of mycetoma cases were obtained from the scientific literature and GIDEON; Acacia records were obtained from the Global Biodiversity Information Facility. We developed ENMs based on digital GIS data layers summarizing soil characteristics, land-surface temperature, and greenness indices to provide a rich picture of environmental variation across Sudan and South Sudan. ENMs were calibrated in known endemic districts and transferred countrywide; model results suggested that risk is greatest in an east-west belt across central Sudan. Visualizing ENMs in environmental dimensions, mycetoma occurs under diverse environmental conditions. We compared niches of mycetoma and Acacia trees, and could not reject the null hypothesis of niche similarity. This study revealed contributions of different environmental factors to mycetoma infection risk, identified suitable environments and regions for transmission, signaled a potential mycetoma-Acacia association, and provided steps towards a robust risk map for the disease.


Journal ArticleDOI
TL;DR: Evaluating these species in terms of completeness of geographic range knowledge accumulated through time, results show that at least 40.9% of species listed as Data Deficient do not appear genuinely to be particularly lacking in data, but rather may be knowledge-deficient, which may be useful in identifying cases in which data are genuinely lacking regarding conservation status of species.

Journal ArticleDOI
TL;DR: Ecological niche models for seven bird species identified a common paleoclimate barrier that coincided with deep genetic structure among populations, resulting in long‐term isolation and genetic differentiation in the Philippines.
Abstract: Avian diversification in oceanic archipelagos is largely attributed to isolation across marine barriers. During glacial maxima, lowered sea levels resulted in repeated land connections between islands joined by shallow seas. Consequently, such islands are not expected to show endemism. However, if climate fluctuations simultaneously caused shifts in suitable environmental conditions, limiting populations to refugia, then occurrence on and dispersal across periodic land bridges are not tenable. To assess the degree to which paleoclimate barriers, rather than marine barriers, drove avian diversification in the Philippine Archipelago, we produced ecological niche models for current-day, glacial maxima, and interglacial climate scenarios to infer potential Pleistocene distributions and paleoclimate barriers. We then tested marine and paleoclimate barriers for correspondence to geographic patterns of population divergence, inferred from DNA sequences from eight codistributed bird species. In all species, deep-water channels corresponded to zones of genetic differentiation, but six species exhibited deeper divergence associated with a periodic land bridge in the southern Philippines. Ecological niche models for these species identified a common paleoclimate barrier that coincided with deep genetic structure among populations. Although dry land connections joined southern Philippine islands during low sea level stands, unfavorable environmental conditions limited populations within landmasses, resulting in long-term isolation and genetic differentiation. These results highlight the complex nature of diversification in archipelagos: marine barriers, changes in connectivity due to sea level change, and climate-induced refugia acted in concert to produce great species diversity and endemism in the Philippines.

Journal ArticleDOI
TL;DR: 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.
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.

Journal ArticleDOI
TL;DR: This work suggests a series of changes to underlying species concepts that would shift the field from one that simply files viruses away in taxonomic boxes to one that can learn important biological lessons from its taxonomy.
Abstract: Virus taxonomy at present is best characterized as a categorization of convenience, without a firm basis in the principles of evolutionary biology Specifically, virus species definitions appear to depend more on tradition and popular opinion among virologists than on firm, quantitative biological evidence I suggest a series of changes to underlying species concepts that would shift the field from one that simply files viruses away in taxonomic boxes to one that can learn important biological lessons from its taxonomy

Journal ArticleDOI
TL;DR: Support is found for the hypothesis that northern Africa was the center of origin for L. rufescens, and that current genetic diversity originated in allopatry, likely promoted by successive glaciations during the Pleistocene.
Abstract: Understanding the evolutionary history of morphologically cryptic species complexes is difficult, and made even more challenging when geographic distributions have been modified by human-mediated dispersal. This situation is common in the Mediterranean Basin where, aside from the environmental heterogeneity of the region, protracted human presence has obscured the biogeographic processes that shaped current diversity. Loxosceles rufescens (Araneae, Sicariidae) is an ideal example: native to the Mediterranean, the species has dispersed worldwide via cohabitation with humans. A previous study revealed considerable molecular diversity, suggesting cryptic species, but relationships among lineages did not correspond to geographic location. Delimitation analyses on cytochrome c oxidase subunit I identified 11 different evolutionary lineages, presenting two contrasting phylogeographic patterns: (1) lineages with well-structured populations in Morocco and Iberia, and (2) lineages lacking geographic structure across the Mediterranean Basin. Dating analyses placed main diversification events in the Pleistocene, and multiple Pleistocene refugia, identified using ecological niche modeling (ENM), are compatible with allopatric differentiation of lineages. Human-mediated transportation appears to have complicated the current biogeography of this medically important and synanthropic spider. We integrated ecological niche models with phylogeographic analyses to elucidate the evolutionary history of L. rufescens in the Mediterranean Basin, with emphasis on the origins of mtDNA diversity. We found support for the hypothesis that northern Africa was the center of origin for L. rufescens, and that current genetic diversity originated in allopatry, likely promoted by successive glaciations during the Pleistocene. We corroborated the scenario of multiple refugia within the Mediterranean, principally in northern Africa, combining results from eight atmosphere–ocean general circulation models (AOGCMs) with two different refugium-delimitation methodologies. ENM results were useful for providing general views of putative refugia, with fine-scale details depending on the level of stringency applied for agreement among models.

Journal ArticleDOI
TL;DR: A detailed model of the lesser grison's potential distribution was generated that validated previous maps, but with improved detail, supporting previous southernmost records, and providing a means of identifying priority sites for conservation and management of the species.
Abstract: The lesser grison (Galictis cuja) is one of the least-known mustelids in the Neotropics, despite its broad range across South America. This study aimed to explore current knowledge of the distribution of the species to identify gaps in knowledge and anticipate its full geographic distribution. Eighty-nine articles have mentioned G. cuja since 1969, but only 13 focused on the species. We generated a detailed model of the species' potential distribution that validated previous maps, but with improved detail, supporting previous southernmost records, and providing a means of identifying priority sites for conservation and management of the species.

Journal ArticleDOI
TL;DR: The null hypothesis is that the ecological niche of the mistletoe will not be distinct from that of its hosts or vectors; alternatively, Mistletoe infections might appear in hosts only in regions where host distributions overlap suitable conditions for the parasite.

Journal ArticleDOI
TL;DR: In this article, a group of colleagues, a network of researchers active in scholarly publishing, spans four continents and multiple disciplines in the natural sciences, humanities, and social sciences, as well as diverse political and economic situations.
Abstract: A level playing field is key for global participation in science and scholarship, particularly with regard to how scientific publications are financed and subsequently accessed. However, there are potential pitfalls of the so-called “Gold” open-access (OA) route, in which author-paid publication charges cover the costs of production and publication. Gold OA plans in which author charges are required may not solve the access problem, but rather may shift the access barrier from reader to writer. Under such plans, everyone may be free to read papers, but it may still be prohibitively expensive to publish them. In a scholarly community that is increasingly global, spread over more and more regions and countries of the world, these publication access barriers may be quite significant. In the present paper, a global suite of colleagues in academe joins this debate. The group of colleagues, a network of researchers active in scholarly publishing, spans four continents and multiple disciplines in the natural sciences, humanities, and social sciences, as well as diverse political and economic situations. We believe that this global sampling of researchers can provide the nuance and perspective necessary to grasp this complex problem. The group was assembled without an attempt to achieve global coverage through random sampling. This contribution differs from other approaches to the open-access problem in several fundamental ways. (A) It is scholar-driven, and thus can represent the ‘other side of the coin’ of scholarly communication. (B) It focuses on narrative report, where scholars were free to orient their responses as they saw fit, rather than being confined to binary or scalar choices. Finally, and perhaps most importantly, (C) it distinguishes among institutions and countries and situations, highlighting inequalities of access among wealthy and economically-challenged nations, and also within countries depending on the size and location of particular institutions.

Journal ArticleDOI
TL;DR: In this article, the authors explore the geographic projection of physiological measurements of optimal temperature, precipitation and relative humidity requirements, as measured under controlled conditions using a climate dataset with high temporal resolution, as a case study for Spanish moss (Tillandsia usneoides), and compare scaling effects with correlative niche models calibrated in Maxent.
Abstract: Aim Ecological niche modelling is being widely applied to help us understand the geographic distributions of species, despite challenges regarding the estimation of fundamental niches that limit model transferability over time and space. Mechanistic models are an alternative,but they can be difficult to implement owing to the detailed knowledge that they require about the organism for full parameterization. In this paper we explore the geographic projection of physiological measurements of optimal temperature,precipitation and relative humidity requirements,as measured under controlled conditions using a climate dataset with high temporal resolution,as a case study for Spanish moss (Tillandsia usneoides),and compare scaling effects with correlative niche models calibrated in Maxent. Location The Americas. Methods We used climate data with a high temporal resolution to understand how often and where populations of Spanish moss occur under optimal and suboptimal conditions with respect to different environmental variables across their geographic range. We used weather station data for the United States with higher spatial resolution to provide a finer-grained view. We also developed an ecological niche model to show how averaged climate data can present inaccurate views of physiological thresholds for the species. Results Few populations of Spanish moss are located at sites that present suboptimal conditions for more than two environmental parameters. The northern distributional limit of Spanish moss is set by minimum temperature requirements, whereas maximum temperatures are less limiting. However, when the same occurrences are analysed with respect to averaged climate data, 95% of populations appear to fall within the optimal physiological intervals. Main conclusions Our analyses revealed that most populations of Spanish moss do not experience optimal ecophysiological conditions for all environmental variables, even over long time-scales. Physiological data may be of limited utility in delimiting suitable areas for populations of species, but they offer unique perspectives on the causes of range limitation.

Journal ArticleDOI
03 Jun 2014-Oryx
TL;DR: In this paper, the authors estimate possible impacts of global climate change on the geographical distribution of the African lion Panthera leo in the coming decades using current lion population occurrence data across Africa and distributions of lions in historical times (6,000-100 years before present) integrated with data on present-day climates to generate ecological niche models.
Abstract: The objective of this study is to estimate possible impacts of global climate change on the geographical distribution of the African lion Panthera leo in the coming decades. Current lion population occurrence data across Africa and distributions of lions in historical times (6,000–100 years before present) were obtained from the literature and integrated with data on present-day climates to generate ecological niche models. Models based on distributions of African lions were tested for predictive ability based on various subsetting approaches and were projected across Asia, Africa and Europe, to retrodict the distribution of the species for the past 6,000 years. These models were highly accurate, giving confidence in future projections. Future potential distributions were predicted by projecting ecological niche models onto three climate scenarios of future greenhouse gas emissions based on eight climate models for the years 2040–2070. The prediction was of relative range stability into the future: few new areas were identified as becoming suitable for the species but large areas of southern Africa and West Africa are expected to become less suitable. Predictions of effects of climate change on potential distributions of lions may assist conservation efforts by clarifying options for mitigation and response.

Journal ArticleDOI
01 Apr 2014-PLOS ONE
TL;DR: Central-eastern China appears to represent an area of high risk for H7N9 spread, but suitable areas were distributed more spottily in the north and only along the coast in the south; highly suitable areas also were identified in western Taiwan.
Abstract: No current funding sources were specifically designate for this study, however, partial support was from the talent introduction program award to GZ in Tianjin Normal University (5RL127). No additional funding was received for this study. The funder had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

Journal ArticleDOI
TL;DR: This research developed an innovative method that calculated the minimum sea level rise needed to inundate each cell in a Digital Elevation Model (DEM) and performed better than the simple “bathtub” approach, especially with sea level rises below 1 m.
Abstract: The rate of sea level rise will roughly double over the next century with a conservative projection of 0.18–0.59 m by 2100 (IPCC 2007). Inundation caused by sea level rise will likely disrupt the physical, economic, and social systems in coastal regions worldwide. All existing methods to assess the potential impacts of sea level rise could only delineate the inundation by a specific sea level rise. In addition to providing another inundation method based on the cost distance GIS function, this research developed an innovative method that calculated the minimum sea level rise needed to inundate each cell in a Digital Elevation Model (DEM). Both methods considered water connectivity and performed better than the simple “bathtub” approach, especially with sea level rises below 1 m. Implementation data structures significantly affected the efficiency of the new method. Several data structures were proposed and compared. Our results indicated the combination of a binary heap and hash table data structure was t...

Journal ArticleDOI
23 Apr 2014-The Auk
TL;DR: A series of new species descriptions in which no type specimen or fragmentary type specimen material was provided as documentation, but a more appropriate approach is documentation of the discovery, but without formal naming of the species, until suitable specimen documentation can be assembled.
Abstract: Recent years have seen a series of new species descriptions in which no type specimen or fragmentary type specimen material was provided as documentation. These descriptions have been controversial, but the Code of Zoological Nomenclature makes clear that such nondiagnostic types are not acceptable specimen documentation. A more appropriate approach is documentation of the discovery, but without formal naming of the species, until suitable specimen documentation can be assembled.


Journal Article
TL;DR: A global suite of colleagues in academe, a network of researchers active in scholarly publishing, spans four continents and multiple disciplines in the natural sciences, humanities, and social sciences, as well as diverse political and economic situations, which distinguishes among institutions and countries and situations.
Abstract: A level playing field is key for global participation in science and scholarship, particularly with regard to how scientific publications are financed and subsequently accessed. However, there are potential pitfalls of the so-called “Gold” open-access (OA) route, in which author-paid publication charges cover the costs of production and publication. Gold OA plans in which author charges are required may not solve the access problem, but rather may shift the access barrier from reader to writer. Under such plans, everyone may be free to read papers, but it may still be prohibitively expensive to publish them. In a scholarly community that is increasingly global, spread over more and more regions and countries of the world, these publication access barriers may be quite significant. In the present paper, a global suite of colleagues in academe joins this debate. The group of colleagues, a network of researchers active in scholarly publishing, spans four continents and multiple disciplines in the natural sciences, humanities, and social sciences, as well as diverse political and economic situations. We believe that this global sampling of researchers can provide the nuance and perspective necessary to grasp this complex problem. The group was assembled without an attempt to achieve global coverage through random sampling. This contribution differs from other approaches to the open-access problem in several fundamental ways. (A) It is scholar-driven, and thus can represent the ‘other side of the coin’ of scholarly communication. (B) It focuses on narrative report, where scholars were free to orient their responses as they saw fit, rather than being confined to binary or scalar choices. Finally, and perhaps most importantly, (C) it distinguishes among institutions and countries and situations, highlighting inequalities of access among wealthy and economically-challenged nations, and also within countries depending on the size and location of particular institutions.