Year: 1987
Type: article
Abstract: The ontogeny of songbird vocalizations has become a classic example of the interaction of genetic and environmental factors in the development of complex behavior (Baptista and Petrinovich 1984).In the bestknown study, Marlet and Tamura (1964) used taped playbacks of song as "tutors" and concluded that White-crowned Sparrows (Zonotrichia leucophrys) learn only conspecific song and will do so only if they hear it between about 10-50 days of age.These findings do not apply to all songbirds as many species learn new songs after 50 days of age (Kroodsma 1982).Moreover, by exposing birds to live tutors, Baptista and Petrinovich (1984, 1986) found that White-crowns will learn songs, even of heterospecifics, after 50 days of age (but see Cunningham and Baker 1983, Baker and Cunningham 1985).Besides its importance in basic ontogeny, vocal development in songbirds is critical to understanding possible evolutionary consequences of dialects, about which there has been much recent controversy (Kroodsma et al. 1984, Baker and Cunningham 1985 and accompanying critiques).We report on the flight whistles (hereafter FWs) developed by captive Brown-headed Cowbirds (Molothrus ater) exposed to live, rather than taped, tutors.The behavioral ontogeny of a brood-parasitic species such as the cowbird is especially interesting because the birds have no known contact with their parents.This has led some (e.g.Mayr 1974) to suggest that cowbirds have a closed developmental program resistant to environmental influences to ensure that vital species-specific behavior develops properly.Although there are genetically programmed aspects to •
Source: The Auk
DOI: 10.2307/4087552
Authors: Stephen I. Rothstein, Robert C. Fleischer
Language: English
Subfield: Developmental Biology
Domain: Life Sciences
Open Access status: green
OpenAlex ID: W2322029782