Abstract
Subspecies have been used in conservation biology to account for intraspecific patterns in genetic diversity, which is crucial to long‐term population viability. Although over 3200 subspecies are currently assessed by the International Union for Conservation of Nature Red List, their biological relevance remains controversial. Here, we analyzed patterns of subspecies counts across more than 33,000 tetrapod species, and using hurdle mixed‐effect models, we modeled subspecies counts as a function of biological and sociocultural factors. Our results revealed a striking decline in the description of subspecies in recent decades, driven mostly by contemporary social factors. Birds exhibited the highest number of recognized subspecies, followed by mammals and reptiles, whereas amphibians currently lack any valid subspecies. Subspecies counts also varied spatially; temperate regions had more subspecies than tropical areas on average, as well as more species whose subspecies counts differ markedly from what would be expected given their attributes. Using multivariate models, we found preserved specimen availability, species range size, and geographic discontinuity (i.e., disjunct populations) as major predictors of subspecies counts. Additionally, well‐studied and recently described species were less likely to have subspecies. Our findings suggested that subspecies recognition is shaped by complex sociocultural and research‐related contexts rather than by purely biological criteria. This misalignment risks skewing conservation priorities, highlighting the need for more evidence‐based approaches that integrate molecular, phenotypic, and geographic data for subspecies delimitation. This approach will help ensure that conservation resources are directed toward biologically meaningful units to enhance the effectiveness of conservation strategies.