The heritability of bigger brain structures in beauteous bouncing birds and the basis of sexual selection due to a better sung song, are recent peculiar interests of mine.
As a recent owner of a pair of Zebra Finches, I have been fascinated by the way they function and communicate, and especially with Werthers' (the male) song. A tinny peeping that fluctuates, usually from a happy springy feeling, to times when he sounds down right pissed off.
As a possibly cruel (though I don’t think so) experiment, I recorded Werthers' singing and occasionally play it back for him. He becomes overly excited, mockingly jumping from perch to perch in, I would guess, a competitive agitation (Charlotte is a beauty after all).
I have this recording on quick rewind and play-back so I’ll play the different (I believe there are 3) variations of the song and surprisingly he, more often than not, responds with the same version as the one played, but seemingly louder, faster and continuous, sometimes over and over, always outdoing the recording of himself.
Charlotte doesn’t seem to notice much of this; I believe she’s preoccupied these days with the nest he’s building in the seed dish.
No doubt the fact that I am currently dealing with the communication and speech/song development in the fledglings of both finch and human these days would account for the sudden interest.
Yesterday on my drive home I heard this incredibly interesting story on NPR that I thought I would share with whoever might be reading this. If you were listening to NPR yesterday, I apologize.
I am going to post my experiments and findings as often as they occur even though I realize I sound like an old lady talking about her birds.
"An elaborate bird song is like a Grand Cherokee in the driveway or an M.D. after the name - a kind of shorthand for all the desirable qualities that a female wants in a mate and wants passed along to the children," said Timoth DeVoogd, professor of psychology and neurobiology and behavior at Cornell.
"Of course these birds are not scholars of evolutionary theory. They don't think Darwin's principle of sexual selection when they make up their minds about which male sings best."
However their choices have an impact on their parenting success, and how they will survive for generations to come.
Apparently, males with the most elaborate songs have bigger brains, a larger HVC (high vocal center) according to Cornell research. And the neurobiologists are intrigued by the fact that the larger brain structures are inherited.
Females consistently choose males with more elaborate songs, though
it has baffled scientists how a female can pick up on the difference between a 38 note song and a 40 note song in just a few minutes.