Carol Whaling

Abstract

Songbirds must learn to sing. Vocal learning involves several different processes,

including selection of an appropriate song to serve as a model, memorization

of the model, and retrieval of the model to direct development of adult song.

To learn to sing, many species must hear song during a sensitive period early in

development. Birds deprived of this experience sing abnormal songs that are not

improved by exposure to song later in life. Selection of a song to serve as a model

for learning is guided by instinct. When young birds raised in captivity are played

tape recordings of their own species’ songs as well as those of other species, they

choose to learn the ones of their own species, demonstrating innate ability to

recognize these songs.

Studies of the neuroanatomy of songbirds have uncovered neural circuits

involved in song learning, production, and perception. I review aspects of the

development and the organization of these brain regions in relationship to song

learning to address the neural basis of sensitive periods and learning preferences.

The knowledge we have gleaned from these studies may provide a new per-

spective from which to approach studies of human music acquisition.

Calls and songs of birds are an almost inescapable part of our sur-

roundings, and reveal how essential vocalizations are in the life of birds.

Simple vocalizations, referred to as calls, often function to maintain

contact among a flock, or alert others to danger or to a potential food

source. Songs, longer and more complex than calls, are used to identify

individuals, establish and defend territory boundaries, attract mates, and

even stimulate the reproductive tract and reproductive behavior of one’s

mate.

Learning plays an important role in the development of song. All

species of songbirds that have been studied to date must learn to sing

(Kroodsma and Baylis 1982). Since songbirds make up almost half of the

existing 9,000 avian species, song learning is presumably widespread. It

also is in other branches of the avian family tree including parrots and

their relatives (Todt 1975; Farabaugh, Brown, and Dooling 1992) and

hummingbirds (Baptista and Schuchmann 1990). Birds with simple

vocalizations, however, such as chickens and doves, do not have to learn

their calls (Konishi 1963; Nottebohm and Nottebohm 1971).

To test whether learning is required for normal song production, birds

are raised in captivity without an opportunity to hear other members of

their species. Chickens raised in such acoustic isolation still sound like

chickens, whereas songbirds sing abnormal, simple songs, called isolate

songs (Marler 1970; Marler and Sherman 1985; figure 5.1). This depen-

dence on learning by many avian species is surprising considering

that even our closest relatives, monkeys and apes, do not have to learn

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What’s Behind a Song? The Neural Basis of Song Learning

in Birds

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