On Thu, Oct 04, 2007 at 08:09:28PM +1000, John Leonard wrote:
> And calls are innate, that is, even birds brought up in isolation from
> any individuals of their species will develop them and use them. But
> song has to be learnt, individuals raised in isolation from other
> members of their species never learn to sing 'proper' songs, much as
> children, if they don't learn to speak by the age of ten or so, never
> do learn the full range of language.
> Oh, and only passerines have song, non-passerines only have calls.
The separation of vocalizations into calls & songs is somewhat arbitrary
and learning isn't used make the separation. The vocalizations of
oscine passerines usually termed songs are thought to almost always
have a learnt component, but sub-oscine passerines (primarily found
in the Americas) also have vocalizations commonly termed songs and
these are thought to be in many cases purely innate. Song learning
has been identified only in a few sub-oscine passerines (Cotingas).
Song learning is also known in a few non-passerines (hummingbirds & parrots).
It is less common to term the vocalization of a non-passerine a song
but experts do this, e.g Kroodsma refers to Whippoorwill song in his
(recommended) book, "The Singing Life of Birds". So the terminology
police can't arrest you for referring to, for example, The laughter
of a Kookaburra as a song - its a complex vocalization with a function
associated with breeding & territory.
Andrew
|
