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ambience: Lyrebird calls
That’s an Australian lyrebird that we’re listening to, but it might not be a lyrebird’s call. The reason is that these birds are mimics and they regularly pick up on songs that aren’t their own. I’m Jim Metzner, and this is the Pulse of the Planet. Walter Boles is a Collection Manager of birds at the Australian Museum.
“They have a, I’d say a fairly typical avian voice box except in many ways it seems to be even less complex than those of many of our birds. So it’s hard to tell why they are such good mimics, and I suspect it’s less with the voice box and more how certain parts of the brain process all these calls.”
One thing seems certain, it takes a lot of trial and error to be a good mimic.
“A lot of birds, if you hear them when they’re first trying to sing, they’re not particularly good — it’s only through practice and by listening to other lyrebirds and the other noises around. So it’s been shown that different parts of the lyrebirds’ range have different vocal repertoires depending on what birds are there that they can learn from and from each others.”
As we learn more about how some birds mimic other species’ calls, we’re still in the dark about why this occurs.
“The reasons for mimicry are still a bit controversial. One is if you develop your own particular repertoire, it’s one way of being individually recognized by females. And another idea on mimicry is that it gives the female birds some indirect indication of how good the territory is that you own because it’s a reflection of how many other birds can be supported by the resources that are there.”
Pulse of the Planet is presented with support provided by the National Science Foundation. I’m Jim Metzner.
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