7 of 8 juvenile chiffchaff males, caught between Jul. 28 and Aug. 18 in southwest Germany, developed song in acoustic isolation which corresponded to the song of their nesting areas (Figs. 1, 2, 3). They must have learned this song institution between about 44 and 100 days of age. One captured bird with divergent syllables probably had not finished crystallizing its song at the end of the experiment.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.