Determinantes de padrões espaciais, ambientais e evolutivos das lacunas hutchinsonianas de serpentes (Squamata: serpentes)

Abstract

Knowledge of the different dimensions of biodiversity is marked by gaps and biases that unevenly affect data availability, being strongly influenced by geographic, historical, and phylogenetic factors. Among these gaps, the Hutchinsonian shortfall—related to the lack of knowledge about tolerance limits to abiotic factors—stands out as particularly relevant in the context of rapid climate change, since the absence of information on thermal tolerance compromises our understanding of species vulnerability, persistence, and future distributions. In this study, we investigated the magnitude of the Hutchinsonian shortfall associated with thermal biology traits of snakes, assessing the distribution and biases of available knowledge across geographic, phylogenetic, and climatic spaces. To this end, we integrated thermal biology data from the literature with spatial, phylogenetic, and environmental analyses. We compiled morphological, physiological, and climatic information from global databases and a systematic review, including data on thermal tolerance, evapotranspiration, and climatic niche under current conditions and future scenarios. Knowledge representativeness was evaluated using niche overlap tests, spatial autocorrelation analyses, and the phylogenetic aggregation index (NRI), in addition to analyses of changes in climatic conditions projected until 2100 under the SSP585 scenario. Our results demonstrate that knowledge of snake thermal biology is limited, strongly biased, and structured across phylogenetic, environmental, and geographic spaces, characterizing a multifaceted Hutchinsonian shortfall. Data are concentrated in a few clades and temperate regions, incompletely representing the group’s climatic niche, particularly for traits associated with minimum thermal tolerance and water balance. This pattern results in extensive portions of climatic space—especially in tropical regions—being systematically underrepresented. Projections of future climate scenarios indicate climatic rearrangements and the emergence of non-analog conditions, increasing uncertainty and limiting ecological inferences and realistic predictions about snake responses to global climate change.