Correlated evolution of morphology and vocal signal structure in Darwin's Finches

Correlated evolution of morphology and vocal signal structure in Darwin's Finches

In this article, Podos challenges the classical theory that mating signal (i.e song) evolution is an accidental byproduct of speciation operating on other environmental factors. Specifically, he refers to beak morphology and questions how the adaptive diversification of beaks has influenced the evolution of song quality by either enhancing or constraining vocal abilities. Considering he begins the article by noting that songs are often used for mating, I infer that he suspects that evolutionary diversification of break size and shape (secondary to ecological changes) may indirectly lead to speciation by changing mating calls.