The Max Planck Institute studied the vocal plasticity of seal pups and they appear to possess innate voice control and understanding of rhythm.
Seals change the intonation and volume of the voice, like humans.
Humans appear to be one of the only animals capable of speech, which requires a range of mental skills and abilities. Among these, vocal learning – the ability to learn to produce new sounds – is fundamental for the development of language. Only a few animals have this trait, including humans, bats, whales, seals and elephants. However, simply possessing the ability to create new sounds is not enough to unlock language. Andrea Ravignani, from the Department of Comparative Bioacoustics at the Max Planck Institute, and colleagues studied the vocal plasticity of seal pups, or the ability to adapt their voice to compensate for their surroundings. They found that puppies can change the intonation and volume of their voices, just like humans. The ability to change volume is common, but pitch change is of requency fundamental, is rare in animals.
“Seals could have this ability thanks to convergent evolution : Vocal plasticity could be a trait that evolved independently in multiple lineages due to similar evolutionary pressures, ” Ravignani said. “In the case of humans and seals, vocal plasticity and learning may be associated with advanced breathing control or singing ability in both species.”
The team also tested the seal pups’ ability to identify rhythmic sounds using recordings from other seals. They edited some of these recordings by changing the tempo and adding beats to see how the seals would react. As a result, the puppies paid much more attention to recordings with regular rhythms and fast tempos.
“We can conclude that very young and untrained seals are able to discriminate the vocalizations of other seals based on their rhythmic properties ,” Ravignani said. “Another mammal then, besides us, shows rhythm processing and vocalization learning; perhaps these two abilities coevolved in both humans and seals.”
- Vocal learning, chorusing seal pups and the evolution of rhythm (as part of the 183rd Meeting of the Acoustical Society of America)