<b>Tropical land-use change disrupts zeta-diversity across taxa</b>

Land-use change causes community turnover via local extinctions and colonisation of disturbance-adapted species, whilst driving biotic homogenization at larger spatial scales ^1,2. Quantification of these processes has focused on beta-diversity metrics, which upweight rarity^3,4. A key question is understanding the impact on rare to common species across space—zeta-diversity ³—in causing community turnover following land-use change. We sampled bird, dung beetle, and orchid communities in 341 locations spanning natural (Andean forests and paramo) and transformed habitats (pasturelands) across ~270 km in the Colombian Andes to reveal that deforestation disrupts zeta-diversity across elevation in two ways. First, local-scale deforestation causes biotic homogenization across bird communities, with pasture retaining twice as many common species (species occurring among multiple communities) than natural habitats, whereas natural habitats retained four times more common dung beetle species than transformed habitats and orchid community turnover remained high across land-uses. Second, anthropogenic transformation of natural habitats rewires biodiversity patterns such that bird and dung beetle communities become entirely structured by dispersal ability and stochastic processes across elevation, whilst orchid communities have low likelihood of holding common species resulting in local extirpation post-deforestation. Thus, retaining natural habitats prevents disrupting biological communities by preserving rare bird and orchid species and maintaining common dung beetles.