Songbirds learn to respond to and imitate their species' songs from an early
age. With each generation, small differences are introduced that result in
distinct variations-called dialects-among geographically isolated
populations of the same species. A research study examined whether
twelve-day-old Ficedula hypoleuca (pied flycatcher) nestlings prefer local
dialects over the unfamiliar dialects of nonlocal F. hypoleuca populations:
the more begging calls the nestlings made in response to a song, the
stronger their preference. The researchers found that nestlings produced
more begging calls in response to their own dialect than to noniocal
dialects. Since song preference plays a role in songbird mate selection, the
finding suggests that
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