Science Enabled by Specimen Data
Espinosa-Chávez, O. J., A. G. Navarro-Sigüenza, H. Rodríguez-Correa, and L. A. Sánchez-González. 2024. Highly divergent sympatric lineages of Leptotila verreauxi (aves: Columbidae) suggest a secondary contact area in the Isthmus of Tehuantepec, Mexico. Avian Research: 100160. https://doi.org/10.1016/j.avrs.2024.100160
Due to a complex geological and biotic history, the Isthmus of Tehuantepec (IT), has been long recognized as a driver for the evolutionary divergence of numerous lowland and highland taxa. Widely distributed in the lowlands of the American continent, the White-Tipped Dove (Leptotila verreauxi) is a polytypic species with 13 recognized subspecies. Four of these have been recorded in Mexico, and the distribution of three abuts at the IT, suggesting a contact zone. To estimate phylogenetic patterns, divergence times and genetic differentiation, we examined two mtDNA (ND2 and COI) and one nDNA (β-fibint 7) markers. We also used correlative ecological niche models (ENM) to assess whether ecological differences across the IT may have acted as a biogeographical boundary. We estimated paleodistributions during the Middle Holocene, Last Glacial Maximum and Last Interglacial, to evaluate the influence of climate changes on the distribution and demographic changes. Our results showed genetically distinct lineages that diverged approximately 2.5 million years ago. Climatic and ecological factors may have played a dual role in promoting differentiation, but also in the formation of a secondary contact zone in the southern IT. Our ecological niche comparisons indicated that the ecological niche of sympatric lineages at the IT are not identical, suggesting niches divergence; in addition, environmental niche models across the region indicated no abrupt biogeographic barriers, but the presence of regions with low suitability. These results suggest that genetic differentiation originated by a vicariant event probably related to environmental factors favored the evolution of different ecological niches. Also, the absence of a biogeographic barrier but the presence of less suitable areas in the contact regions, suggest that secondary contact zones may be also maintained by climatic factors for the eastern group, but also by biotic interactions for the western group.
Munna, A. H., N. A. Amuri, P. Hieronimo, and D. A. Woiso. 2023. Modelling ecological niches of Sclerocarya birrea subspecies in Tanzania under the current and future climates. Silva Fennica 57. https://doi.org/10.14214/sf.23009
The information on ecological niches of the Marula tree, Sclerocarya birrea (A. Rich.) Horchst. subspecies are needed for sustainable management of this tree, considering its nutritional, economic, and ecological benefits. However, despite Tanzania being regarded as a global genetic center of diversity of S. birrea, information on the subspecies ecological niches is lacking. We aimed to model ecological niches of S. birrea subspecies in Tanzania under the current and future climates. Ecological niches under the current climate were modelled by using ecological niche models in MaxEnt using climatic, edaphic, and topographical variables, and subspecies occurrence data. The Hadley Climate Center and National Center for Atmospheric Research's Earth System Models were used to predict ecological niches under the medium and high greenhouse gases emission scenarios for the years 2050 and 2080. Area under the curves (AUCs) were used to assess the accuracy of the models. The results show that the models were robust, with AUCs of 0.85–0.95. Annual and seasonal precipitation, elevation, and soil cation exchange capacity are the key environmental factors that define the ecological niches of the S. birrea subspecies. Ecological niches of subsp. caffra, multifoliata, and birrea are currently found in 30, 22, and 21 regions, and occupy 184 814 km2, 139 918 km2, and 28 446 km2 of Tanzania's land area respectively, which will contract by 0.4–44% due to climate change. Currently, 31–51% of ecological niches are under Tanzania’s protected areas network. The findings are important in guiding the development of conservation and domestication strategies for the S. birrea subspecies in Tanzania.
Brunner, A., J. R. G. Márquez, and S. Domisch. 2024. Downscaling future land cover scenarios for freshwater fish distribution models under climate change. Limnologica 104: 126139. https://doi.org/10.1016/j.limno.2023.126139
The decreasing freshwater biodiversity trend can be attributed to anthropogenic impacts in terms of climate and land cover change. For targeted conservation efforts, mapping and understanding the distribution of freshwater organisms consists of an important knowledge gap. Spatial modelling approaches offer valuable insights into present-day biodiversity patterns and potential future trajectories, however methodological constraints still hamper the applicability of addressing future climate and land cover change concurrently in one modelling workflow. Compared to climate-only projections, spatially explicit and high-resolution land cover projections have seen less attention, and the lack of such data challenges modelling efforts to predict the possible future effects of land cover change especially on freshwater organisms. Here we demonstrate a workflow where we downscale future land cover projection data from the Shared Socioeconomic Pathway (SSP) scenarios for South America at 1 km2 spatial resolution, to then predict the future habitat suitability patterns of the Colombian fish fauna. Specifically, we show how the land cover data can be converted from plain numbers into a spatially explicit representation for multiple SSP scenarios and at high spatial resolution, employing freshwater-specific downscaling aspects when spatially allocating the land cover category grid cells, and how it can be fitted into an ensemble species distribution modelling approach of 1209 fish species. Our toolbox consists of a suite of open-source tools, including Dinamica EGO, R, GRASS GIS and GDAL, and we provide the code and necessary steps to reproduce the workflow for other study areas. We highlight the feasibility of the downscaling, but also underline the potential challenges regarding the spatial scale and the size of the spatial units of analysis.
Leão, C. F., M. S. Lima Ribeiro, K. Moraes, G. S. R. Gonçalves, and M. G. M. Lima. 2023. Climate change and carnivores: shifts in the distribution and effectiveness of protected areas in the Amazon. PeerJ 11: e15887. https://doi.org/10.7717/peerj.15887
Background Carnivore mammals are animals vulnerable to human interference, such as climate change and deforestation. Their distribution and persistence are affected by such impacts, mainly in tropical regions such as the Amazon. Due to the importance of carnivores in the maintenance and functioning of the ecosystem, they are extremely important animals for conservation. We evaluated the impact of climate change on the geographic distribution of carnivores in the Amazon using Species Distribution Models (SDMs). Do we seek to answer the following questions: (1) What is the effect of climate change on the distribution of carnivores in the Amazon? (2) Will carnivore species lose or gain representation within the Protected Areas (PAs) of the Amazon in the future? Methods We evaluated the distribution area of 16 species of carnivores mammals in the Amazon, based on two future climate scenarios (RCP 4.5 and RCP 8.5) for the year 2070. For the construction of the SDMs we used bioclimatic and vegetation cover variables (land type). Based on these models, we calculated the area loss and climate suitability of the species, as well as the effectiveness of the protected areas inserted in the Amazon. We estimated the effectiveness of PAs on the individual persistence of carnivores in the future, for this, we used the SDMs to perform the gap analysis. Finally, we analyze the effectiveness of PAs in protecting taxonomic richness in future scenarios. Results The SDMs showed satisfactory predictive performance, with Jaccard values above 0.85 and AUC above 0.91 for all species. In the present and for the future climate scenarios, we observe a reduction of potencial distribution in both future scenarios (RCP4.5 and RCP8.5), where five species will be negatively affected by climate change in the RCP 4.5 future scenario and eight in the RCP 8.5 scenario. The remaining species stay stable in terms of total area. All species in the study showed a loss of climatic suitability. Some species lost almost all climatic suitability in the RCP 8.5 scenario. According to the GAP analysis, all species are protected within the PAs both in the current scenario and in both future climate scenarios. From the null models, we found that in all climate scenarios, the PAs are not efficient in protecting species richness.
Quitete Portela, R. de C., L. Tourinho, T. Viana dos Santos, and M. M. Vale. 2023. Juçara palm ecological interactions threatened by climate and land‐cover changes. Biotropica. https://doi.org/10.1111/btp.13257
Ongoing climate change has caused well‐documented displacements of species' geographic distribution to newly climatically suitable areas. Ecological niche models (ENM) are widely used to project such climate‐induced changes but typically ignore species' interspecific interactions that might facilitate or prevent its establishment in new areas. Here, we projected the change in the distribution of Juçara Palm (Euterpe edulis Mart., Arecaceae), a neotropical threatened palm, taking into consideration its ecological interactions. We run ENMs of E. edulis, plus its known seed dispersers (15 bird species) and predators (19 birds and mammals) under current and future climatic conditions. Additionally, for E. edulis, we removed deforested areas from the model. When considering only climate, climate change has a positive impact on E. edulis, with a predicted westward expansion and a modest southward contraction, with a 26% net gain in distribution by 2060. When removing deforested areas, however, climate change harms E. edulis, with a 66% predicted net distribution loss. Within the palm's distribution in this more realistic model, there is also a predicted reduction in the richness of its dispersers and predators. We conclude that the possible benefits of climate change to E. edulis' distribution are overshadowed by widespread habitat loss, and that global change is likely to disrupt some of its ecological interactions. The outcome of the interplay between the negative impact of the loss of dispersers, and the benefit of the loss of predators, is unclear, but the large contraction of E. edulis' range predicted here foresees a dim future for the species.
Vázquez-Rueda, E., A. P. Cuervo-Robayo, and J. Ayala-Berdon. 2023. Forest dependency could be more important than dispersal capacity for habitat connectivity of four species of insectivorous bats inhabiting a highly anthropized region in central Mexico. Mammal Research. https://doi.org/10.1007/s13364-023-00707-0
The maintenance, restoration, and improvement of habitat structure are critical for biodiversity conservation. Under this context, studies assessing habitat connectivity become essential, especially those focused on anthropized regions holding high species richness. We calculated the habitat connectivity of four species of insectivorous bats with different dispersal capacity and habitat preferences in a highly anthropized region in central Mexico, Idionycteris phyllotis and Myotis thysanodes , with a high dispersal capacity and forest-dependency, and Eptesicus fuscus with a low dispersal capacity, and Tadarida brasiliensis with a high dispersal capacity, as the more tolerant bat species to anthropogenic disturbance. We developed niche-based species distribution models to identify suitable habitat patches for each species. We then assessed habitat connectivity and the importance of suitable habitat patches for maintaining connectivity using a graph theory approach. Our results showed that forest dependency was most important than dispersal capacity for connectivity. We also found that the Iztaccíhuatl-Popocatépetl mountain, a National Park comprising 4.2% of natural vegetation in the study area, was the most critical patch for maintaining connectivity for most of the study species. Our study demonstrates the importance of conserving the remnants of natural vegetation for maintaining habitat connectivity within a fragmented landscape and demonstrates the importance of conserving protected areas as well as other remnants of vegetation for the maintenance of habitat connectivity within a fragmented landscape.
Cruz, J. A., J. A. Velasco, J. Arroyo-Cabrales, and E. Johnson. 2023. Paleoclimatic Reconstruction Based on the Late Pleistocene San Josecito Cave Stratum 720 Fauna Using Fossil Mammals, Reptiles, and Birds. Diversity 15: 881. https://doi.org/10.3390/d15070881
Advances in technology have equipped paleobiologists with new analytical tools to assess the fossil record. The functional traits of vertebrates have been used to infer paleoenvironmental conditions. In Quaternary deposits, birds are the second-most-studied group after mammals. They are considered a poor paleoambiental proxy because their high vagility and phenotypic plasticity allow them to respond more effectively to climate change. Investigating multiple groups is important, but it is not often attempted. Biogeographical and climatic niche information concerning small mammals, reptiles, and birds have been used to infer the paleoclimatic conditions present during the Late Pleistocene at San Josecito Cave (~28,000 14C years BP), Mexico. Warmer and dryer conditions are inferred with respect to the present. The use of all of the groups of small vertebrates is recommended because they represent an assemblage of species that have gone through a series of environmental filters in the past. Individually, different vertebrate groups provide different paleoclimatic information. Birds are a good proxy for inferring paleoprecipitation but not paleotemperature. Together, reptiles and small mammals are a good proxy for inferring paleoprecipitation and paleotemperature, but reptiles alone are a bad proxy, and mammals alone are a good proxy for inferring paleotemperature and precipitation. The current paleoclimatic results coupled with those of a previous vegetation structure analysis indicate the presence of non-analog paleoenvironmental conditions during the Late Pleistocene in the San Josecito Cave area. This situation would explain the presence of a disharmonious fauna and the extinction of several taxa when these conditions later disappeared and do not reappear again.
Haubrock, P. J., A. Kulessa, R. L. Macêdo, and A. S. Tarkan. 2023. Exploring the distribution of the non-native Umbra pygmaea across European freshwater ecoregions through climatic suitability and locally consumed diet. Aquatic Sciences 85. https://doi.org/10.1007/s00027-023-00989-1
The East American mudminnow Umbra pygmaea was introduced to Europe a century ago and is now established in at least six European countries. Although considered harmless and with low spread potential, this fish species shows potential to colonise a broad range of habitats due to its wide environmental tolerance. Stomach content analyses were conducted over 3 years to obtain a first insight into this species' diet, which could indicate the potential to alter the biotic composition of recipient ecosystems. The results showed that this fish can potentially have a high impact on insects, fish, and even amphibians through predation. Species distribution models further indicated that environmental conditions of Central European ecoregions are currently a limiting factor for the spread of this species which seems, at least for now, to be driven by anthropogenically driven introductions. Considering the species’ potential to be invasive and impact native biota, monitoring of potential spread is recommended.
Bharti, D. K., P. Y. Pawar, G. D. Edgecombe, and J. Joshi. 2023. Genetic diversity varies with species traits and latitude in predatory soil arthropods (Myriapoda: Chilopoda). Global Ecology and Biogeography. https://doi.org/10.1111/geb.13709
Aim To investigate the drivers of intra-specific genetic diversity in centipedes, a group of ancient predatory soil arthropods. Location Asia, Australasia and Europe. Time Period Present. Major Taxa Studied Centipedes (Class: Chilopoda). Methods We assembled a database of 1245 mitochondrial cytochrome c oxidase subunit I sequences representing 128 centipede species from all five orders of Chilopoda. This sequence dataset was used to estimate genetic diversity for centipede species and compare its distribution with estimates from other arthropod groups. We studied the variation in centipede genetic diversity with species traits and biogeography using a beta regression framework, controlling for the effect of shared evolutionary history within a family. Results A wide variation in genetic diversity across centipede species (0–0.1713) falls towards the higher end of values among arthropods. Overall, 27.57% of the variation in mitochondrial COI genetic diversity in centipedes was explained by a combination of predictors related to life history and biogeography. Genetic diversity decreased with body size and latitudinal position of sampled localities, was greater in species showing maternal care and increased with geographic distance among conspecifics. Main Conclusions Centipedes fall towards the higher end of genetic diversity among arthropods, which may be related to their long evolutionary history and low dispersal ability. In centipedes, the negative association of body size with genetic diversity may be mediated by its influence on local abundance or the influence of ecological strategy on long-term population history. Species with maternal care had higher genetic diversity, which goes against expectations and needs further scrutiny. Hemispheric differences in genetic diversity can be due to historic climatic stability and lower seasonality in the southern hemisphere. Overall, we find that despite the differences in mean genetic diversity among animals, similar processes related to life-history strategy and biogeography are associated with the variation within them.
Fell, H. G., M. Jones, S. Atkinson, N. C. Stenseth, and A. C. Algar. 2023. The role of reservoir species in mediating plague’s dynamic response to climate. Royal Society Open Science 10. https://doi.org/10.1098/rsos.230021
The distribution and transmission of Yersinia pestis , the bacterial agent of plague, responds dynamically to climate, both within wildlife reservoirs and human populations. The exact mechanisms mediating plague's response to climate are still poorly understood, particularly across large environmentally heterogeneous regions encompassing several reservoir species. A heterogeneous response to precipitation was observed in plague intensity across northern and southern China during the Third Pandemic. This has been attributed to the response of reservoir species in each region. We use environmental niche modelling and hindcasting methods to test the response of a broad range of reservoir species to precipitation. We find little support for the hypothesis that the response of reservoir species to precipitation mediated the impact of precipitation on plague intensity. We instead observed that precipitation variables were of limited importance in defining species niches and rarely showed the expected response to precipitation across northern and southern China. These findings do not suggest that precipitation–reservoir species dynamics never influence plague intensity but that instead, the response of reservoir species to precipitation across a single biome cannot be assumed and that limited numbers of reservoir species may have a disproportional impact upon plague intensity.