ABSTRACT Aim Global environmental change encompasses shifts in climate and land use, which are evident in tropical mountains. Both processes impose selective pressures on species, resulting in changes to their distribution and diversity. Using a historic dataset from 1990 to 1993 that was systematically replicated in 2015, we tested whether the elevational distribution of dung beetle species has changed over 25 years in response to climate variations and land use changes. Location Perote Volcano Mountain Range (PVMR) in the Mexican Transition Zone (MTZ). Taxon Neotropical and Holarctic dung beetles (Scarabaeinae and Geotrupinae). Methods We sampled 15 sites along an elevation gradient ranging from 0 to 3400 m a.s.l. in two different periods, 25 years apart. For each site, we obtained the environmental variables (temperature and precipitation) and changes in land use between the two periods using meteorological station data, remote sensing and interpolation methods. Using STATICO and co‐inertia analysis, we identified temporal changes in species distribution in response to environmental change. We also assessed temporal beta‐diversity dynamics (i.e., species gain and loss) and mean elevation range by classifying species according to their biogeographic affinity. In addition, we analysed environmental dissimilarity between pairs of sites from the historic and recent surveys using beta‐diversity. Results Dung beetle assemblages shifted upwards by ~200 m in elevation over time, and we detected a 31% decline in abundance and a 16% decline in species richness between the historic and recent surveys. Changes in species elevation range were not uniform. Five distinct patterns were identified: range expansions (dominated by Neotropical species), range contractions (present in both Neotropical and Holarctic species), range shifts (mostly Holarctic species), local extinctions (mainly Holarctic species) and local colonization (Neotropical and Holarctic species). Two processes predominate in the temporal dynamics of beta‐diversity along the elevation gradient: biotic homogenization by colonization and biotic differentiation by extinction. Holarctic species were more sensitive to distributional shifts at intermediate and high elevations than Neotropical species. Beta‐diversity shows a negative relationship with climate change across sampling periods. Main Conclusion These results underscore the vulnerability of mountain dung beetle species to global environmental change. Their biogeographic affinities and evolutionary history influence this vulnerability. The Holarctic species are the most prone to extinction. Furthermore, this study emphasizes the importance of tropical mountains as sentinels for understanding the responses of biodiversity to environmental changes.
Hernández‐Rivera et al. (2026) studied this question.