Longer Wing Bones in Warmer Climates Suggest a Role of Thermoregulation in Bird Wing Evolution

作者：Brian C. Weeks, Christina Harvey, Joseph A. Tobias, Catherine Sheard, Zhizhuo Zhou, David F. Fouhey · 发表于：Global Ecology and Biogeography · 年份：2025 · DOI：10.1111/geb.70033 · 被引用次数：9 · 研究领域：Avian ecology and behavior、Animal Behavior and Reproduction、Physiological and biochemical adaptations

ABSTRACT Aim The tendency for animals in warmer climates to be longer‐limbed (Allen's Rule) is widely attributed to the demands of thermoregulation. The role of thermoregulation in structuring bird wings, however, has been overshadowed by the selective demands placed on wings by flight. We test whether occurrence in warmer climates is associated with longer wing bones. Location Global. Time Period Current. Major Taxa Studied Aves: Passeriformes. Methods Using computer vision, we measure wing‐bone length from photographs of museum skeletal specimens for 1520 species of passerine birds. We then model the relationship between wing‐bone length and temperature, accounting for allometry, the demands of flight efficiency and manoeuvrability, and a range of ecological and environmental variables. Results Wing bones are longer in warmer climates. Our models, largely as a result of allometric effects, explain nearly all the variation in wing‐bone length in our data, with a marginal R 2 = 0.80 and a conditional R 2 > 0.99. Main Conclusions Across 1520 species of birds, higher temperatures are associated with longer wing bones, as predicted by Allen's Rule. The vascularised musculature along these bones is maximally uncovered when birds actively hold their wings away from their bodies to aid in cooling or during flight. Conversely, the musculature along the wing bones is insulated by feathering when at rest, such that wings play a minor role in heat exchange when individuals are less ...