When Does the Latitudinal Diversity Gradient Hold? Scale- and Mechanism-Based Conditions

The scale dependence of the latitudinal diversity gradient (LDG) has been widely acknowledged, yet its boundaries of applicability remain unclear. Here, we develop a multi-scale analytical framework to assess the environmental determinants of species richness across major taxonomic groups (plants, birds, mammals, reptiles, amphibians and total species), integrating climatic and topographic predictors with simulated richness data. Our results show that the latitudinal diversity gradient exhibits significant scale dependence, and that the ecological relationships at the overall and local levels display a statistical pattern similar to Simpson’s paradox. This divergence arises from the latitudinal turnover of dominant environmental drivers, coupled with their spatial continuity across transition zones. These findings indicate that the validity of the LDG is shaped by two key dimensions of environmental filtering, namely the spatial differentiation and transmission of dominant drivers, which together determine the applicability boundaries of environmental drivers. Information & Authors Information Version history Copyright This work is licensed under a Non Exclusive No Reuse License.

Authors Metrics & Citations Metrics Article Usage 203views 88downloads Citations Download citation Yange Wang, Zhou Fang, Zhongde Huang, et al. When Does the Latitudinal Diversity Gradient Hold? Scale- and Mechanism-Based Conditions. Authorea. 24 July 2025. DOI: https://doi.org/10.22541/au.175336621.10374354/v1 DOI: https://doi.org/10.22541/au.175336621.10374354/v1 If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. Simply select your manager software from the list below and click Download. For more information or tips please see 'Downloading to a citation manager' in the Help menu.