Climate explains global functional trait variation in bees

Many studies have linked climate to functional trait variation at local scales, yet macroecological evidence for these trends is scarce.In particular, data is limiting for multi-dimensional traits that are challenging to quantify at scale, though many of these traits have outsize effects on thermal performance.We leveraged computer vision to quantify bee traits (hairiness and lightness) from images.We demonstrate that climate shapes variation in these traits at a global scale, with both traits increasing with maximum environmental temperatures and lightness decreasing with precipitation.Deserts were hotspots for bees covered in light-colored hairs, adaptations that may mitigate heat stress and represent convergent evolution with other desert organisms.These results support major ecogeographical rules and emphasize the role of climate in shaping bee phenotypic diversity.