François Génier

The surge of biodiversity data availability in recent decades has allowed researchers to ask questions on previously unthinkable scales, but knowledge gaps still remain. In this study, we aim to quantify potential gains to insect data on the Global Biodiversity Information Facility (GBIF) through further digitisation of natural history collections, assess to what degree this would fill biases in spatial and environmental record coverage, and deepen understanding of environmental bias with regard to climate rarity. Using mainland Afrotropical records for Catharsius Hope, 1837 (Coleoptera: Scarabaeidae), we compared inventory completeness of GBIF data to a dataset which combined these with records from a recent taxonomic revision. We analysed how this improved dataset reduced regional and environmental bias in the distribution of occurrence records using an approach that identifies well‐surveyed spatial units of 100 × 100km as well as emerging techniques to classify rarity of climates. We found that the number of cells for which inventory completeness could be calculated, as well as coverage of climate types by ‘well‐sampled’ cells, increased threefold when using the combined set compared to the GBIF set. Improvements to sampling in Central and Western Africa were particularly striking, and coverage of rare climates was similarly improved, as not a single well‐sampled cell from the GBIF data alone occurred in the rarest climate types. These findings support existing literature that suggests data gaps on GBIF are still pervasive, especially for insects and in the tropics, and so, is not yet ready to serve as a standalone data source for all taxa. However, we show that natural history collections hold the necessary information to fill many of these gaps, and their further digitisation should be a priority.

Abstract Climate change is expected to exert varying effects on different taxa and species, affecting both their abundance and distribution ranges. Previous studies have used climate niche models (CNMs) to estimate shifts in the distribution of insects, without considering whether the effects of climate change may vary depending on their functional traits (nesting strategy, body size, and period of activity). Dung beetles, a taxonomic group characterized by using mammalian dung as their primary source of food (coprophagy), respond differently to temperature fluctuations depending on their nesting strategy and body size. In this study, we used CNMs to estimate shifts in the distribution ranges of 33 species of dung beetles under climate change scenarios (the shared socioeconomic pathways from the IPCC’s Sixth Assessment Report) for the period 2041–2060 in North America and Central America (excluding Canada due to absence of data). Additionally, we analyzed whether the effects of climate change on the distribution ranges of the studied species are significantly different depending on their functional traits. Our results showed that climate change will negatively affect the distribution range of the majority of the studied species by the middle of this century, with contrasting effects depending on their nesting strategy and body size. The smallest species and dwellers showed an increase in their occurrence probabilities and percentage of highly suitable habitats, whereas larger-bodied species and tunnelers showed a decrease in both. We found no significant differences between diurnal and nocturnal species. Our results show that by incorporating key traits related to temperature response and ecosystem function, we can analyze shifts in species distribution ranges more precisely, enabling the identification of patterns across functional categories and predictions about their future.

Given the heightened vulnerability of deserts to climate change, this study aims to provide a comprehensive analysis of avian species diversity across ten global deserts to identify distinct diversity gradients and relatedness. Identify the difference from global patterns in avian migratory proportions and the underlying drivers for assessing the vulnerability and resilience of these desert ecosystems. Crowd-sourced avian diversity data of 2374 species from GBIF.org was used as a key analytical tool to study the diversity gradient across the ten major deserts. The variance in correlation patterns between avian ecological and behavioral traits across deserts were analyzed employing data of 1930 common avian species from AVONET. The analysis included comparisons of bird diversity, migratory patterns and trophic niches between Tropic of Cancer (TCan) and Tropic of Capricorn (TCap) deserts. Significant variations in bird diversity among the deserts were found. Deserts near the TCan exhibited higher bird diversity than in TCap deserts. TCan deserts had a higher prevalence of migratory species, facilitated by a broader niche breadth among sedentary species, which reduces niche competition and allows the influx of migratory invertivores. Proportion of migratory birds is higher in TCan deserts due to wider trophic niche but is significantly lower than the global average for the same latitude range. The findings highlight the need for targeted conservation strategies to protect avian diversity in the TCan deserts and mitigate extinction risks in TCap deserts, ensuring the resilience of these critical ecosystems.

AbstractAbstract. neighboring countries. Recently, an increase in biological surveys and access to natural preserves has led to a better understanding of species distributions in Nicaragua and across Central America. Here, we provide new departmental records for three species of didelphid, 18 chiropterans (Phyllostomidae, Molossidae, Vespertilionidae), one geomyid, and one mustelid from 21 sites across the country. This work underscores the need for additional sampling across Nicaragua to fill gaps in the known distribution of many species. This information can facilitate or inform conservation actions in established and proposed preserves in Nicaragua.

The Mexican Transition Zone is a biogeographically complex area where old and new lineages of Neotropical and Nearctic affinities overlap. Its biota was assembled by successive dispersal events of cenocrons, which are sets of taxa that dispersed during a given time interval from both North and South America and then diversified in the area. The Mexican Plateau cenocron, with Neotropical affinities, is found in temperate and dry climates in the Nearctic region. We hypothesised that it underwent an adaptive shift in environmental niche. We tested this hypothesis using a phylogenetic comparative framework, measuring phylogenetic signal and fitting to single optima macroevolutionary models, and an Ornstein‐Uhlenbeck macroevolutionary model with multiple optima. We used phylogenetic and distributional information of the tribe Phanaeini to assess whether there exists a distinction in conservatism between the earliest (Mexican Plateau) and most recent (Typical Neotropical) cenocrons within the Mexican Transition Zone (MTZ) as this tribe stands as a classic example of the dispersal and diversification patterns of cenocrons originating in the Neotropics. We identified different shifts in environmental requirements that match the niche description of the Mexican Plateau cenocron, suggesting that it was established through multiple adaptive shifts in the Mexican Transition Zone.

This paper presents an exploratory study on the taxonomic diversity of pre-Hispanic archaeofaunas in the South-Central Andes (SCA; western South America) from the Pleistocene-Holocene boundary to the Late-Holocene. The SCA is a complex of diverse environments and has undergone distinct climate events for the last 13,000 years, such as the occurrence of warmer and drier conditions in the Middle-Holocene. The South-Central Andean area was part of the larger Andes interaction area, which was a primary center for animal and plant domestication and the emergence of agro-pastoralist economies. Since subsistence was key to these processes, the SCA provides a relevant case study on the interactions among environment, foodways and sociocultural evolution. Taxonomic diversity was used here as a proxy for diet breadth. A total of 268 archaeofaunal assemblages were sampled from the zooarchaeological literature. Reviewed variables included the cultural chronology and spatial coordinates of the assemblages, as well as the presence and abundance of taxa at the family rank. Taxonomic diversity covered two dimensions: composition (families present in each assemblage) and structure (quantitative relationships among taxa), which was measured through richness (NTAXA), ubiquity and relative abundance (NISP based rank-order). Despite the uneven distribution of samples, the analyses revealed the following trends: (1) a moderate relationship between NTAXA and distance from coastline for most of the Holocene; (2) a potential decrease in assemblage richness for coastal ecoregions during the Late-Holocene; and (3) a generalized increase in the relative abundance of Camelidae.

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.

AbstractInsects that inhabit high‐altitude ecosystems are an ecologically specialized group whose distribution is restricted by the presence of biogeographical barriers. These biogeographical constraints are thought to mould the shape of some insect structures because of environmental pressures that may produce better adaptations in extreme environments. We evaluated the potential distribution of Homocopris achamas and Uroxys coarctatus in two life regions (the Andean region and the Páramo region) found in the Andes of Colombia, and we determined if there were differences in their morphology along an elevational gradient. To determine the potential distribution of the species, we obtained geographical data through the systematic search of databases and entomological collections that we modelled under the maximum entropy model. We then evaluated the morphological variations by measuring geometric structures such as the clypeus (MC), the eye (ME) and the area of the anterior tibia (TA). We found that both species along the entire gradient exhibited the following characteristics: H. achamas was dominant in the Páramo region and showed two population nuclei separated by a wide biogeographic barrier, while U. coarctatus was more dominant in the Andean region and was distributed only in the northern Andes. Both were always linked to ecosystems with open vegetation that was both natural or intervened. H. achamas did not show changes in the shape of the structures while U. coarctatus showed differences in MC and ME. We suggested that livestock activity could act as an engine for breaking down biogeographical barriers allowing the distribution of a species to expand, and with this distributional expansion changes in the morphological structures of some species linked to their phenotypic plasticity could be promoted.

The popularization of citizen-science platforms has increased the amount of data available in a fine spatial and temporal resolution, which can be used to fill distribution knowledge gaps through probabilistic maps. In this study, we gathered expert-based information and used species distribution models to produce two independent maps of the greater rhea ( Rhea americana , Rheiformes, Rheidae) distribution in the state of Rio Grande do Sul, Brazil. We integrated municipality level detection/non-detection data from five citizen-science datasets into a Bayesian site occupancy model, accounting for false negatives, sampling effort, habitat covariates, and spatial autocorrelation. We addressed whether habitat (grassland and crop field cover, number of rural properties) and spatial autocorrelation explains the realized occurrence of the species and compared model-based and expert-based occurrence maps. The mean estimated percentage of occupied municipalities was 48% (239 out of 497 municipalities), whereas experts declared 21% of the municipalities (103) as occupied by the species. While both mapping approaches showed greater rhea presence in most municipalities of the Pampa biome, they disagreed in the majority of the municipalities in the Atlantic Forest, where more fieldwork must be undertaken. The greater rhea distribution was exclusively explained by the spatial autocorrelation component, suggesting that the species expanded its distribution towards the north of the state, reaching the Atlantic Forest, following deforestation and agriculture expansion.

South Africa is considered a megadiverse country, with exceptionally high plant and relatively high animal species richness and endemism. The country’s species have been surveyed and studied for over 200 years, resulting in extensive natural science collections and a vast number of scientific papers and books. This study assessed whether existing data portals provide access to occurrence data and investigated the extent of the data in Global Biodiversity Information Facility and its completeness for plants and selected invertebrate taxa. The main focus was preserved specimen data, but some observation data from iNaturalist were also considered for selected analyses. Records that include species-level identification and co-ordinates were mapped in QGIS to show the coverage of collection localities across the country. The records that fall within the mountain range spatial layer were then extracted and counted to identify density of records per mountain range for various taxa. Forty percent of plant records are from mountain localities, and the Atlantic Cape Fold Mountains had the highest density of records. Table Mountain has been extensively collected for plants and invertebrates. A large proportion of the records for invertebrates lacked species-level identification and co-ordinates, resulting in a low number of records for analyses. The accessible data are only a relatively small subset of existing collections, and digitisation and data upgrading is considered a high priority before collecting gaps can be addressed by targeted surveys.