Uncovering the drivers of anuran age structure.

Age structure provides a vital perspective for understanding population ecology, evolutionary biology, and conservation biology. Here, we compiled data on maximum age, average age, and age at sexual maturity for 184 anuran species across 22 families from published literature. We evaluated the effects of climate factors, geographical gradients, habitat types, and body size on age-structure traits. Furthermore, we projected future trends in age structure under various climate change scenarios. Our results indicate that broad habitat categories did not significantly influence age-related traits, likely due to the buffering capacity of microhabitats, which mitigates climate-related differences across habitats. In contrast, age traits exhibited sex-specific responses to environmental drivers, potentially reflecting divergent reproductive energy allocation strategies and metabolic trade-offs between males and females. Future projections suggest that climate change will lead to a widespread decline in both lifespan and average age across anurans, resulting in a shift toward younger populations with shorter lifespans and a general trend toward smaller body size. These findings deepen our understanding of how anurans respond to environmental changes and provide a scientific foundation for developing effective conservation strategies.