The pitch of the sounds is also determined by the length of the specie's trachea and the inflation of the air sacs. Some Passerines can produce two sounds simultaneously, by the control of air through each bronchus. Right now, we don't really know. Some birds, such as hawks and owls, probably utilize larger parts of their brains in order to efficiently capture their prey. They also have to remember how to locate their nests.
Wild parrots pair off early, and pairs stay together within a flock of their own species.
Communication seems to be an important part of mate recognition in a flock of identical-looking birds. All rights reserved.