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bioRxiv · 10.1101/2025.10.30.685361

Pollinators in Mexico. Spatial patterns show exceptions to global trends

Nava-Bolanos, A.·Osorio-Olvera, L.·Soberon, J.
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Abstract

Pollinators are declining globally, yet their biodiversity patterns in megadiverse regions remain unclear. We analyzed four major pollinator groups across one of the worlds most diverse regions -Mexico and adjacent areas. Using species distribution models, we generated presence- absence matrices (1,135 species in 165,078 grid cells) and applied range-diversity plots with a new randomization approach, to explore richness and endemism. Results reveal sharp contrasts: hummingbirds, bats, hawkmoths, and some bee families show the expected tropical richness peak, whereas other bees peak in arid lands of northern Mexico and the southwestern US. Endemism also diverges, with vertebrates concentrated in the tropics and bees in deserts. These findings challenge assumptions of uniform pollinator diversity patterns and demonstrate that conservation cannot rely on one-size-fits-all solutions. Our framework offers spatial tools to identify biodiversity structure and inform conservation and policy in the face of land-use change, agrochemicals, invasive species, and climate pressures.

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Nava-Bolanos, A., Osorio-Olvera, L., Soberon, J.. 2025-10-31. Pollinators in Mexico. Spatial patterns show exceptions to global trends. https://doi.org/10.1101/2025.10.30.685361

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