Animal species share a universal speech rhythm

The scientists analyzed over 2,000 audio recordings of mammals, birds, amphibians, insects, reptiles, and fish, as the University of Geneva announced on Thursday. To compare the rhythms of these vocalizations, they developed a method that allows the tempo of the vocalizations to be calculated consistently.

The result: Most species produce their calls, songs, or other acoustic signals at a rate of about two to three units per second. According to the university, there was a clear concentration at a frequency of about 2.8 hertz—that is, 2.8 acoustic signals per second. These findings were published in the journal “PLoS Biology.”

Neither body weight, lung volume, nor the complexity of social life alters this rhythm. Nor does it matter whether an animal lives in water, in the air, or on land.

Humans are no exception

Humans are no exception here either. Although the human speech rhythm is slightly higher than the animal average due to the structure of syllables, words, and sentences. However, in difficult communication situations—such as in the presence of ambient noise or when speaking with young children—people spontaneously slow down their speech rate.

The researchers therefore suspect that the origin lies deeper. This shared rhythm corresponds to so-called delta oscillations—slow brain waves that aid in processing temporal information. Accordingly, acoustic communication may have adapted to this tempo over the course of evolution. Put simply: animals transmit information at a pace that their brains can process particularly efficiently.

“This shared rhythm may not only reflect how brains process sounds; it could also represent a kind of universal synchronization that facilitates communication between species,” explained lead author Théophane Piette in the press release.

In addition to the University of Geneva, the University of Zurich and the Institut Pasteur in Paris were also involved in the study.