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Body size predicts the rate of contemporary morphological change in birds

May 8, 2023
Across the globe, bird morphology is changing rapidly. Although trajectories of change are frequently consistent across studies, rates of change among species vary in magnitude—a phenomenon that remains unexplained. By analyzing two independently collected datasets demonstrating consistent changes in morphology in 129 species, we show that rates of phenotypic change are negatively correlated with body size—that is, smaller birds are changing faster. Why smaller-bodied species are changing faster is unknown, but we found little support for the hypothesis that generation length explains variation in the rates of change. Rather, body size appears to be a primary mediator of species’ phenotypic responses to contemporary climatic change and should be considered when testing hypotheses about the drivers of change.
Publication Year 2023
Title Body size predicts the rate of contemporary morphological change in birds
DOI 10.1073/pnas.2206971120
Authors Marketa Zimova, Brian Weeks, David E. Willard, Sean T Giery, Vitek Jirinec, Ryan C. Burner, Benjamin M Winger
Publication Type Article
Publication Subtype Journal Article
Series Title Proceedings of the National Academy of Sciences (PNAS)
Index ID 70243359
Record Source USGS Publications Warehouse
USGS Organization Upper Midwest Environmental Sciences Center