Philip Hershkovitz

Island ecosystems have significant conservation value owing to their higher endemic biotas. Moreover, studies of regional communities that compare differences in species composition (species dissimilarity) among islands and the mainland suggest that community assembly on islands is different from that on the mainland. However, the uniqueness of island biotic assembly has been little studied at the global scale, nor have phylogenetic information or alien species been considered in these patterns. We evaluate taxonomic and phylogenetic change from one community to the next, focusing on differences in species composition between mainland-mainland (M-M) pairs compared to differences between mainland-island pairs (M-I) and between island-island pairs (I-I), using herpetofauna on islands and adjacent mainland areas worldwide. Our analyses detect greater taxonomic and phylogenetic dissimilarity for M-I and I-I comparisons than predicted by M-M model, indicating different island herpetofauna assembly patterns compared with mainland counterparts across the world. However, this higher M-I dissimilarity has been significantly decreased after considering alien species. Our results provide global evidence on the importance of island biodiversity conservation from the aspect of both the taxonomic and phylogenetic uniqueness of island biotic assembly.

We assessed changes in fundamental climate‐niche space for lizard and snake species in western North America under modeled climate scenarios to inform natural resource managers of possible shifts in species distributions. We generated eight distribution models for each of 130 snake and lizard species in western North America under six time‐by‐climate scenarios. We combined the highest‐performing models per species into a single ensemble model for each scenario. Maps were generated from the ensemble models to depict climate‐niche space for each species and scenario. Patterns of species richness based on climate suitability and niche shifts were calculated from the projections at the scale of the entire study area and individual states and provinces, from Canada to Mexico. Squamate species' climate‐niche space for the recent‐time climate scenario and published known ranges were highly correlated (r = 0.81). Overall, reptile climate‐niche space was projected to move northward in the future. Sixty‐eight percent of species were projected to expand their current climate‐niche space rather than to shift, contract, or remain stable. Only 8.5% of species were projected to lose climate‐niche space in the future, and these species primarily occurred in Mexico and the southwestern U.S. We found few species were projected to lose all suitable climate‐niche space at the state or province level, although species were often predicted to occupy novel areas, such as at higher elevations. Most squamate species were projected to increase their climate‐niche space in future climate scenarios. As climate niches move northward, species are predicted to cross administrative borders, resulting in novel conservation issues for local landowners and natural resource agencies. However, information on species dispersal abilities, landscape connectivity, biophysical tolerances, and habitat suitability is needed to contextualize predictions relative to realized future niche expansions.

Myrmecophaga tridactyla Linnaeus, 1758 is the largest extant anteater, being distributed in most biomes from southern Central America and northern South America. Herein, we analyzed cranial and postcranial elements of three partial skeletons of M. tridactyla found submerged in Abismo Anhumas cave (Bonito, Mato Grosso do Sul, Brazil). The bones collected were the skull (LEG 2598), left humerus (LEG 2601), ungueal phalanx (LEG 2602), and lumbar vertebrae (LEG 2599; LEG 2600). Radiocarbon dating and isotope analyses indicate that these animals lived between 360 and 560 cal a BP in an arboreal to open savanna habitat associated with the Cerrado, a Seasonal Dry Forest. Radiocarbon‐dated oxygen isotopes are possibly in agreement with dated oxygen isotopes found in stalagmites, suggesting a wet period between 442–364 cal a BP in the region. Finally, we created paleo‐species distribution models, which allowed the generation of a consensus map showing a historically stable area between 21 and 6 ka for this species. Currently, more than 50% of this area has been destroyed by human activity.

The Neotropics are a global biodiversity hotspot that has undergone dramatic land use changes over the last decades. However, a temporal perspective on the continental-wide distributions of species in this region is still missing. To unveil it, we model the entire area of occupancy of five Neotropical carnivore species at two time periods (2000–2013 and 2014–2021) using integrated species distribution models (ISDMs) in a Bayesian framework. The carnivores are the jaguarundi (Herpailurus yagouaroundi), margay (Leopardus wiedii), maned wolf (Chrysocyon brachyurus), tayra (Eira barbara), and giant otter (Pteronura brasiliensis). We mapped the temporal change, the areas where gains and losses accumulated for all species (hotspots of change) and calculated the temporal species turnover and change in spatial turnover. We show that (1) most carnivore species have declined their area of occupancy (i.e., range size) in the last two decades, (2) their diversity has decreased over time, mostly in the Chaco region, and (3) that hotspots of fast species composition turnover are in Chaco, the Caatinga region, and northwest of Mexico. We discuss how these newly identified hotspots of change overlap with regions of well-known and pronounced land use transformation. These estimated patterns of overall decline are alarming, more so given that four out of the five species had been classified as not threatened by IUCN. The official global threat status of these species may need to be re-evaluated. All this would be invisible if standard forecasts, local expert knowledge, or static threat criteria, such as range size, were used. We thus provide a new approach to evaluate past species range dynamics based on multiple lines of evidence, which can be employed over more species in the future, particularly in under-sampled regions.

Today, climate adaptation strategies are at the forefront in wildlife management and protection studies. This study aimed to model and map the effects of global climate change on the Andean bear, which is in the vulnerable category and distributed in South America. For this purpose, 20 environmental variables and 19 high-resolution Chelsa climate maps that could be effective on Andean bear modeling were created. Moreover, the Maximum Entropy method, which is frequently preferred in species distribution modeling, was preferred. The current habitat suitability model of the Andean bear was in the “very good” model category with the training data set ROC value of 0.973 and the test data set ROC value of 0.972. The variables contributing to the current model are roughness index (41.1%), isothermality (38%), elevation (14%), and annual mean temperature (6.9%), respectively. Variables contributing to the current Andean bear model have been simulated in different scenarios (SSP126/SSP370/SSP585) for the year 2100. However, it has been determined that Andean bear habitats will shrink according to the SSP126 Chelsa climate scenario of the year 2100, these habitats will fragment according to the SSP370 scenario, and brown bear habitats will disappear in some regions in the SSP585 scenario. In conclusion, this study raises alarms that the possible decrease in Andean bear habitats will be approximately 67.3% by the year 2100 due to global climate change.

Abstract Gymnophthalmids are a diverse lineage of Neotropical lizards that present challenges in the understanding of their phylogenetic relationships and biogeographic history. Using a densely sampled phylogeny and distribution data, we investigated their biogeography at the family level. Dividing South and Central America into 12 regions, we tested six biogeographic models considering dispersal-extinction, vicariance, and founder events. Our analysis revealed high taxonomic and phylogenetic endemism in the Andes, Amazon, and Guiana Shield. The best-fit model identified the Guiana Shield as the likely ancestral area of the family, with dispersal events dominating over vicariance. Key areas for species interchange were the Amazon, Northern Andes, and Guiana Shield. The core regions of diversification included the Andes, Amazon, and Guiana Shield, with elevated species richness and biotic interchange events during the Eocene and Oligocene. The Guiana Shield stood out as a stronghold of gymnophthalmid diversity, driven by dispersal rates and ancient lineages. Our findings challenge previous hypotheses about the diversification of these lizards, suggesting a colonization pattern from lowlands to high elevations rather than the South-to-North Speciation Hypothesis for Andean lineages.

Leopardus wiedii and Leopardus pardalis are endangered small felids. Its main altitudinal range expands from sea level to 1,500 m. Camera traps were placed in the Matawi Indigenous Park on the Nevado de Toluca Volcano. Photographic records were obtained of L. wiedii at 3,207 masl and of L. pardalis at 3,307 masl. This is the highest altitudinal record for margay in its distribution, and for ocelot is the highest in the northern hemisphere.

La Chucha de Agua, Chironectes minimus, es quizás uno de los marsupiales más crípticos en el Neotrópico. A pesar de que cuenta con registros puntuales sobre su presencia a lo largo de su distribución, sus reportes son escasos en ecosistemas circundantes a zonas periurbanas. Aquí reportamos una nueva localidad de presencia para la especie al suroriente del Valle de Aburrá, Antioquia, Colombia. A partir de análisis de los patrones actividad, se identificó que la especie presentó una tendencia nocturna, principalmente entre las 19h00 y las 00h00. Con respecto a la revisión y sobre su distribución altitudinal, a pesar de que existen registros a diferentes intervalos altitudinales, los registros sobre los 2.000 msnm son escasos. Reportamos un registro a 2.660 msnm y corroboramos uno a 2.562 msnm en el área de estudio. Igualmente, a partir de la revisión resaltamos el registro de mayor altitud a 2.800 msnm el cual ampliaría su rango actual.

Species’ range size is a fundamental unit of analysis in biodiversity research, given its association with extinction risk and species richness. One of its most notable patterns is its positive relationship with latitude, which has been considered an ecogeographical rule called Rapoport’s rule. Despite this rule being confirmed for various taxonomic groups, its validity has been widely discussed and several taxa still lack a formal assessment. Different hypotheses have been proposed to explain their potential mechanisms, with those related to temperature and elevational being the most supported thus far. In this study, we employed two level of analyses (cross-species and assemblage) to investigate the validity of Rapoport’s rule in spiny lizards (genus Sceloporus). Additionally, we evaluated four environmental-related hypotheses (minimum temperature, temperature variability, temperature stability since the last glacial maximum, and elevation) posed to explain such pattern, contrasting our results to those patterns expected under a null model of range position. Our results provided support for Rapoport’s rule at both levels of analyses, contrasting with null expectations. Consistently, minimum temperature and elevation were the most relevant variables explaining the spatial variation in range size. At the cross-species level, our null simulations revealed that both variables deviated significantly from random expectations. Conversely, at the assemblage level, none of the variables were statistically different from the expected relationships. We discussed the implication of our findings in relation to the ecology and evolution of spiny lizards.

Las listas de aves han sido instrumentos poderosos para desarrollar medidas efectivas de conservación. En este trabajo se presenta una lista de aves de la provincia de Imbabura, que forma parte de los Andes Tropicales, la zona con la mayor diversidad biológica del mundo. A pesar de que Imbabura ha sido reconocida como Geoparque Mundial de la UNESCO y el 35% de su superficie está protegida, la localidad también cuenta con una extensa historia de fragmentación del paisaje y degradación del hábitat que se remonta a la época precolombina. Se seleccionaron los registros de aves para Imbabura, en GBIF (1818-2022). También se examinó Google Scholar y los repositorios digitales de tesis, buscando referencias con registros de aves de la provincia. Los sitios de avistamiento de aves más recientes (2018-2020), se cargaron en un sistema de información geográfica y se vincularon a una capa de cobertura de uso del suelo. Se usaron 4 categorías: (1) URB, zona antrópica; (2) AGR, tierra agrícola; (3) NAT, tanto bosque como vegetación arbustiva y herbácea; y (4) AQU, cuerpos de agua. Se calculó la ocurrencia de cada especie en cada tipo de paisaje. Los resultados son un inventario de 753 especies registradas en Imbabura, con 146 en alguna categoría de amenaza. Debido a la gran cantidad de aves en esta provincia, las cuales representan el 45% de las especies registradas en Ecuador, es fundamental implementar políticas públicas en apoyo a la conservación de esta biodiversidad. Este estudio resalta la relevancia de la ciencia ciudadana y las plataformas de bases de datos gratuitas como herramientas de apoyo a la investigación.