Dolphins use high-pitched voices for their babies too, study finds

It’s the funny habit we all immediately adopt when talking to very young children.

But high baby talk isn’t limited to humans — dolphins do it too, according to a new study.

Researchers analyzed the vocalizations of 19 wild adult female bottlenose dolphins, which were recorded during catch-and-release health assessments near Florida’s Sarasota Bay.

They specifically looked for the high-pitched whistles of the dolphins, both in the presence and absence of their offspring.

They found that the dolphins consistently produced whistles with higher maximum frequencies and greater frequency ranges in the presence of their offspring, compared to the whistles they made when alone or with other individuals.

The researchers, from the Woods Hole Oceanographic Institution in Massachusetts, said this shift in communication may help capture the attention of their young and promote bonding and vocal learning.

In the journal Proceedings of the National Academy of Sciences, they wrote: “”Motherese” is a speech pattern that is nearly universal across cultures and languages ​​in human caregivers who interact with children.

“But the evidence among non-human species is sparse. Here we report evidence for motherese in the bottlenose dolphin, a species that parallels humans in their long-term mother-offspring bonds and lifelong vocal learning.

“The median age of calves in our sample was two years, which is well within the age range for child-directed communication in humans.”

Bottlenose dolphins grow to 13 feet (4 m) in length and 1,300 pounds (590 kg). They travel alone or in groups of about 12, but herds of hundreds of dolphins have been spotted. In the photo Atlantic bottlenose dolphin (Tursiops truncatus; file photo)

According to the authors, the findings also suggest that bottlenose dolphins are a promising animal to help study the evolution of vocal learning and language in humans.

Previous studies have shown that adult male zebra finches change the acoustics of their songs when singing in the presence of juveniles compared to when singing alone or to females.

Meanwhile, adult squirrel monkeys and rhesus macaques use different types of vocalization when communicating with young monkeys compared to older ones.

Separate research from the University of Florida suggests that baby talk may help babies produce their own speech.

By mimicking the sound of a smaller vocal tract, scientists believe adults give babies an idea of ​​how the words should sound from their own mouths.