The short version
- Across more than 350 bird species, songs use small pitch steps, steady rhythms and a longer last note, the same three habits found in human speech and song.
- Birds that learn their songs, like songbirds and hummingbirds, were no more humanlike than birds born knowing theirs.
- The researchers think the shared habits come from the body, such as breathing, rather than from learning, but that idea was not tested.
Biologists at McGill University have found that bird songs and human voices share three basic habits. Logan James and Jon Sakata took recordings of more than 350 bird species from xeno-canto, a citizen-science sound archive, and hand-marked about 70,000 song units. They compared those with speech and song in 52 languages. Their paper is published in Science.
The three shared habits are small pitch steps between notes, regular and predictable rhythms, and a stretched last unit at the end of a phrase. The team expected birds that learn their songs, such as songbirds and hummingbirds, to sound more humanlike than suboscines and nightjars, which are born knowing their songs. They found very little evidence for that. Sakata noted the sample takes in “groups of birds that have historically been overlooked.”
James suggests the patterns come from shared limits of the body. Big pitch jumps are hard to produce, and “phrase-final elongation in birds and humans could be due to breathing patterns when we vocalise.” That explanation is a proposal, not something the study tested. The data are archive recordings, compared after the fact.
