Darwinian shortfall and macroecological patterns in genetic data of Tocantins-Araguaia basin fishes

Abstract

Genetic information is crucial for species identification, population genetics structure, evolutionary relationships, and biodiversity monitoring. It helps address biodiversity gaps related to Linnean (taxonomic uncertainty) and Darwinian (phylogenetic knowledge) shortfalls. Understanding these gaps can guide data collection to reduce these shortfalls. This study focuses on compiling genetic data for 748 fish species in the Tocantins-Araguaia basin, examining the number of unique genomic regions and the individual regions sampled per species. We also investigated the factors that determine genetic data availability by linking it with macroecological predictors. Our findings reveal that fewer than one-third of endemic species have genetic resources available. The Darwinian shortfall-the lack of phylogenetic knowledge-is a key factor limiting genetic data, with species experiencing more of this shortfall having less genetic information. The study underscores the need for increased genetic sampling of endemic species and more sampling of individual regions to better assess biological information like population structure.