Philip Arthur Silverstone-Sopkin

The genus Bauhinia Plumier ex Linnaeus s.l. (Fabaceae) includes c. 380 species of trees, shrubs, lianas and herbs, distributed in pantropical regions and with previous fossil records from the late Paleocene to the Pliocene, mainly recovered from Asia. Here we report the earliest fossil record of Bauhinia s.l., in the form of a naturally folded leaf from the middle Paleocene of the Sanshui Basin, Guangdong, South China. Based on detailed morphological comparisons, the fossil is named Bauhinia sanshuiensis sp. nov. Its discovery indicates that Bauhinia s.l. had already appeared in its modern diversity centre at least by the middle Paleocene. The results of Biomod2 species distribution modelling quantitatively support the significance of the Kohistan–Ladakh Island Arc in facilitating the floristic exchange of Bauhinia s.l. between Africa and Asia. The diversification and modernization of Bauhinia s.l. in China are discussed in detail based on substantial fossil evidence, underscoring China's crucial role in the phytogeographic history of this genus. Nearest relative analysis for Bauhinia sanshuiensis suggests that it may have been a vine or shrub, adapted to temperatures similar to those of modern Sanshui, but with less precipitation.

Abstract Trichomes are diverse and functionally important plant structures that vary in response to selection pressures across ecological gradients and evolutionary timescales. Classic hypotheses predict higher investment in trichomes in arid environments, at lower latitudes, and in long-lived species, as well as shifts in trichome production to reduce conflict between defense traits and mutualisms. However, tests of these hypotheses often rely on aggregate trichome metrics and neglect the rich diversity of trichome phenotypes. Here, we collected data on fine-scale patterns of trichome length, density, and type in 52 species of blazingstars (Mentzelia: Loasaceae) and tested whether individual trichome traits were consistent with existing adaptive hypotheses. Contrary to longstanding hypotheses, we found that Mentzelia species tend to display greater trichome investment in less arid environments and at higher latitudes. Barbed trichomes are significantly less common on the upper surface of the leaf, possibly reducing defense-pollination conflict. Species with larger petals (a proxy for reliance on insect pollinators) also shift investment away from insect-trapping hairs on the underside of the leaf. Examining trichome types separately revealed that different morphologies show distinct responses to abiotic and biotic factors, demonstrating the need to consider multiple axes of diversity when testing adaptive hypotheses for complex traits.

Abstract Snake conservation in Colombia is limited by the lack of information on ecological aspects and distribution ranges, particularly at the departmental level. Herein, we analyzed the state of knowledge of snakes in the department of Tolima, based on a thorough review of literature, and biological collection databases. We found 91 species documented either in literature (82) or museum collections (67). 24 species reported in literature are not supported by specimens in collections and nine species in museum collections don’t have been documented in the literature. We found a large gap in snake occurrence records throughout the department. Remarkably, 48 species reported for the department are outside of their current accepted distribution emphasizing the need of ID corroboration. There are only 35 snake species that have all the necessary information to corroborate their presence in the department, showing the need for a more thorough taxonomic effort to clearly define the actual snake richness. These results serve as a basis for future research and reflect the need to join efforts to characterize and understand the ophidian fauna of the department of Tolima and across Colombia.

En Santander, Colombia, asociado al valle del Magdalena Medio se presentan serranías con remanentes boscosos que contrastan con las zonas deforestadas de las partes bajas. Presentamos una serie (90 especímenes de 48 especies) de la Serranía de La Paz, Betulia, catalogada en la Colección de Ornitología del Museo de Historia Natural de la Universidad Industrial de Santander (UIS-AV) y que proviene principalmente de una expedición en 2023 con el objetivo de estudiar su avifauna a partir de especímenes. La composición de especies de esta serie se comparó con la de otras series de UIS-AV recolectadas recientemente en el Magdalena Medio, y con una serie recolectada en la misma serranía en 1956 cuya información fue obtenida en el GBIF. Nuestra serie de la Serranía de La Paz comparte más especies con un área de bosque continuo en Bolívar que con fragmentos de bosque en Santander. Aunque varias especies de la Serranía de La Paz se registran en otros sitios del Magdalena Medio, nuestra serie incluye a Cotinga nattererii, Trogon rufus y Trogon caligatus que son especies con pocos especímenes para Santander que fueron recolectados hace más de 70 años, además de Euphonia concinna que representa un registro novedoso para el departamento. El 90 % de las especies recolectadas en 1956 están en UIS-AV o se registraron en 2023, pero Psarocolius wagleri, Cacicus cela y Falco sparverius, estuvieron ausentes. La Serranía de La Paz tiene especies de aves características de bosques del Magdalena Medio y puede ser un sitio apropiado para conservarlas.

Describing the geographic range of aquatic species is crucial for biodiversity conservation and management. This study comprehensively assesses commonly used methods for constructing geographic ranges and estimating their sizes in freshwater environments, focusing on the Curimatidae family of tropical freshwater fishes distributed in Central and South America. Our main objective was to evaluate different range estimation methods, including convex hull polygons, alpha‐shape polygons with a fixed alpha‐value, dynamic alpha‐shape polygons, expert maps and species distribution models (SDMs).We used georeferenced data from various sources to delineate species' ranges within their hydrographic basins of occurrence. Geographic ranges for each species were reconstructed using the five methods. For the four polygon methods (i.e., excluding SDMs), two ranges were constructed: (i) polygons considering the whole terrestrial surface (unrestricted) and (ii) polygons considering only freshwater bodies (restricted). Specific environmental variables of freshwater systems were employed for the SDMs. Then, we assessed the differences in range sizes among methods and within each method (excluding SDMs) considering unrestricted and restricted polygons.Our results revealed significant variations in range size estimates among the methods. Specifically, the convex hull method produced larger range sizes than the other methods. Additionally, our comparison between range size estimates using unrestricted and water body‐restricted polygons revealed a consistent trend: unrestricted polygons estimated ranges that were eight times larger than those restricted to water bodies. Moreover, restricting polygons to water bodies resulted in ranges closely matching those estimated by SDMs, indicating the effectiveness of this adjustment procedure.We highlight the notable variability in range size estimates among different methods, underscoring the need to carefully select the one appropriate for given research goals. For example, expert maps could be helpful for quick assessments of species' distribution and diversity when these are readily available. Convex hulls are suitable for quickly identifying potential conservation areas and assessing the overall species range in biodiversity monitoring. Dynamic alpha is appropriate for species with fragmented distributions, as they can capture discontinuities in range delimitation. Static alpha provides a balanced method for range size estimation when ecological information is limited, offering a practical solution for ecological and conservation assessments. SDMs are ideal for detecting species‐environment relationships and identifying unexplored areas where a species might occur. Additionally, adjusting estimated ranges by considering the species' life forms, in this case, associated with water bodies, explicitly restricts their distribution to the actually occupied habitats.Although we focused on the Curimatidae fish family, our study has implications applicable to other freshwater species, providing crucial information on the variability in range size estimates. By thoroughly assessing the methods and their impacts on range size estimates, our study contributes useful guidelines for selecting the appropriate method based on data availability, its spatial arrangement and specific research goals. This contributes to a deeper understanding of commonly used range estimation methods and supports their application and replicability in future studies, potentially aiding biodiversity conservation decision‐making at large spatial scales.

The search for sustainable alternatives to petroleum has driven research on biofuels, with a focus on those derived from organic biomass. This study centres on macaúba ( Acrocomia aculeata ), a promising oilseed for biodiesel production. Advances in cultivation techniques and the mapping of climatically suitable areas are essential to consolidate the use of this species in the energy sector. This work aimed to utilise predictive modelling with the CLIMEX software to assess the current and future climatic suitability of macaúba in the context of climate change. Data on the global distribution of macaúba, growth and stress parameters, as well as climatic variables, were collected. The modelling was conducted based on the A2 SRES scenario for the present, 2050, 2080, and 2100, including the generation of the Weekly Growth Index. Results indicated high suitability in tropical regions, particularly in Brazil and Indonesia. However, future projections highlight significant challenges due to rising temperatures and reduced rainfall. The study provides a critical perspective to guide sustainable policies in the energy sector, underscoring the potential of macaúba as a viable biodiesel source while warning of the challenges posed by climate change.

Dispersal ability may play a major role in determining whether a species will persist under climate change. We used models of dispersal, employing a wide range of intrinsic species-specific dispersal factors, in conjunction with ecological niche models (ENM) and climate predictions to simulate whether distributions of North American cold-adapted amphibians will increase or decrease, and which aspects of dispersal most influence this prediction. We used ENM values as a proxy for habitat suitability, predicted a changing climate under three shared socio-economic pathways (SSP2-4.5, SSP3-7.0, and SSP5-8.5) representing three carbon emission scenarios, and conducted a sensitivity analysis on the effect of dispersal factors on range dynamics. We then used simulations focused only on the southern edge of ranges to determine the likelihood of individuals colonizing towards the core. Predicted range shifts depended on emission scenario, dispersal factors, and species’ initial geography. Inclusion of dispersal parameters was critical in predicting range shifts, in particular for high carbon-emission scenarios where contraction was more likely than expansion, although specific responses varied with species initial geography. Dispersal distance, probability of dispersal, and long-distance dispersal were often the most important parameters for predicting final range size. Similarly, dispersal parameters results in complete loss to complete emigration of southern range individuals towards the core. These models predict that for some species in the more rapid warming scenarios, translocation efforts will be needed to mitigate potential loss of genetic variation at the southern edges and the overall size of the species’ ranges unless carbon emissions are reduced.

Bioenergy is considered among the main mitigation strategies to meet a green-growth development paradigm of 1.5 °C. However, climate change has been dramatically restructuring agriculture and damaging crops, threatening the achievement of global food security and bioenergy goals. Studies have shown that succulent plants through their water efficient and highly temperature-drought-tolerant Crassulacean Acid Metabolism (CAM) pathway, could be a key opportunity to meet future energy demands under global change scenarios. However, specific bioenergy potentials under alternative management conditions, irrigation, and land availability that minimize resource conflicts with food production, biodiversity transgressions, or water withdrawals in water scarce regions, remain unclear. Here, we estimate under a bottom-up approach the global bioenergy potentials of four relevant CAM species on recently abandoned croplands and arid marginal lands, unravelling the interdependencies between land availability, water requirements and climatic conditions at the global scale. We identify a potential of 16–36 Ej yr−1 (27–62% of current bioenergy demand) in abandoned croplands depending on local and management factors. Rainfed CAM potentials (16 Ej yr−1) are comparable with the potentials of bioenergy crops such as miscanthus (19 Ej yr−1) under similar environmental conditions. However, the water requirement of CAM species to reach this potential is 24–30% of what is expected for C3 and C4 bioenergy crops. Additionally, we identify a carbon sequestration potential via plant growth of −3.09 Pg C yr−1 between 1960 and 2020, which reveals an underestimated opportunity in arid marginal lands. We highlight the remarkable contribution of the CAM pathway as a nature-based solution under global change scenarios.

Natural history museums harbor invaluable resources for conserving endangered species by providing insights into the mechanism of historical population declines. We conducted data synthesis to better understand the extinction factors of the iconic Jambato Harlequin frog, Atelopus ignescens, which was widespread in the Ecuadorian Andes before 1985 but vanished in 1988. We synthesized historical data from natural history museums, the Global Biodiversity Information Facility (GBIF), and mtDNA sequences to examine whether Batrachochytrium dendrobatidis (Bd) fungus infection, climate change, and/or their interaction contributed to the rapid population decline. We found excessive rare alleles reflected in the negative Tajima's D estimated from the mtDNA samples from 1984, indicating a selective sweep or population bottleneck. Sex and geography showed stronger effects on adult body sizes than Bd epizootic timing. The body sizes of adult males formed a geographic cline. Species distribution modeling based on temperature and precipitation accurately predicted the occupancy of A. ignescens in 1960-69, which further projected a rapid decline in species distribution between 1970-2020. This investigation revealed strong climate effect and weak epizootics effect on A. ignescens extinction, and inspires future museum genomic studies to dissect the potential climatic maladaptation behind dramatic historical extinctions.

The flowering phenology of many tropical mountain forest tree species remains poorly understood, including flowering synchrony and its drivers across neotropical ecosystems. We obtained herbarium records for 427 tree species from a long-term monitoring transect on the northwestern Ecuadorian Andes, sourced from the Global Biodiversity Information Facility and the Herbario Nacional del Ecuador. Using machine learning algorithms, we identified flowering phenophases from digitized specimen labels and applied circular statistics to build phenological calendars across six climatic regions within the neotropics. We found 47 939 herbarium records, of which 14 938 were classified as flowering by Random Forest Models. We constructed phenological calendars for six regions and 86 species with at least 20 flowering records. Phenological patterns varied considerably across regions, among species within regions, and within species across regions. There was limited interannual synchronicity in flowering patterns within regions primarily driven by bimodal species whose flowering peaks coincided with irradiance peaks. The predominantly high variability of phenological patterns among species and within species likely confers adaptative advantages by reducing interspecific competition during reproductive periods and promoting species coexistence in highly diverse regions with little or no seasonality.