SEAS postdoctoral fellow Marketa Zimova is a member of the research team that completed the new study, "Balancing selection and drift in a polymorphic salamander metapopulation," published today in Biology Letters (The Royal Society Publishing).

Balancing selection and drift in a polymorphic salamander metapopulation

Historical resurveys offer unique insights into evolutionary mechanisms, but are rarely conducted at the metapopulation scale. A team of researchers, including Marketa Zimova, a SEAS postdoctoral fellow supported by the University of Michigan’s Institute for Global Change Biology, resurveyed a metapopulation of spotted salamanders (Ambystoma maculatum) to understand the evolutionary drivers of frequency variation in an egg mass colour polymorphism. They found that this metapopulation was demographically, phenotypically, and environmentally stable over the last three decades. Further analysis revealed evidence for two modes of evolution in this metapopulation—genetic drift and balancing selection.

“Our findings present a clear view of contemporary evolution in colour morph frequency and demonstrate the importance of metapopulation-scale studies for capturing a broad range of evolutionary dynamics," says Zimova.

Authors: Sean T. Giery, Marketa Zimova, Dana L. Drake, Mark C. Urban

Read the press release, "Dueling evolutionary forces drive rapid evolution of salamander coloration."

Read more at Biology Letters (The Royal Society Publishing).