Argentine researchers have succeeded in “reading” the thoughts of birds by reproducing the melodies that play in a loop in their heads when they sleep.
Scientists already knew that the electrical activity of a sleeping bird’s brain matched, at certain times, that observed when it sings. This nocturnal brain activity even causes the muscles in its throat and chest to move, just as if the animal were awake.
However, in their study published in the journal Chaos —a journal devoted to “complex systems” and “non-linear dynamics”—the researchers wanted to go further by measuring, during sleep, the movement of the vocal muscles of the Great Kiskadee, a bird from Brazil and Guyana. Then, using a physical model normally used to predict the sounds produced by a wind instrument, they were able to recreate the song associated with these movements.
The melodies thus obtained were very similar to real bird songs, the researchers pointed out in an article in the magazine New Scientist. For example, one of these melodies corresponded to the tune sung by the Kiskadee Tyrant when he fights to protect his territory. Moreover, on the video of the sleeping bird, the researchers observed that its feathers were then raised on its head, as if during a fight against a rival.
These results are a further argument for those who believe that birds can dream like humans, even if they do not use formal language. The authors of the study now propose repeating the experiment with other birds such as the nightingale, which can sing more than a hundred different melodies. By comparing “waking” songs to “dreaming” songs, they will be able to determine whether sleep plays a role in learning bird songs.
