Female bottlenose dolphins whistle at a higher pitch when communicating with their young, mirroring the “baby talk” humans use. This behavior could help improve bonding and learning in baby dolphins.
When people interact with babies, they often speak in a high-pitched, singsong cadence. This modified speech pattern is common to almost all human cultures and vocal languages.
There is evidence that some other animals may also have special ways of communicating with their young, including zebra finches, gorillas, and monkeys.
Bottlenose dolphins produce a distinctive whistle unique to each individual, known as their signature whistle.
“I have been interested in dolphin mother-calf communication for a long time, which could help us understand the process of how they develop their characteristic whistles,” he says. Laela Sayigh at the Woods Hole Oceanographic Institution in Massachusetts.
To test whether their characteristic whistles change when they communicate with their young, Sayigh and colleagues analyzed the whistles of 19 adult female common bottlenose dolphins (Tursiops truncatus) in waters near Sarasota Bay, Florida, which were recorded over a 34-year period, both with and without their young.
They found that when the dolphins were with their young, they produced whistles with a higher frequency, or pitch, and a much wider range of frequencies than at other times.
“The modified whistle still conveys the identity of the animal,” says a team member. frans jensen in woods hole Oceanographic Institution. “The subtle change in the higher frequency that dolphins use mirrors the pitch changes we see in humans.”
Just like in humans, these modified vocalizations could help promote vocal learning in dolphins, Jensen says, but they don’t have evidence for this yet.
Studying how animals communicate with their young could provide more insight into the evolutionary history behind vocal learning in animals and, ultimately, language in humans, Sayigh says. “It is absolutely essential to have basic knowledge about other species and how they communicate.”
“I would be really interested to see if dolphins also change their whistles when they interact with each other’s babies, which is what happens in humans,” he says. julie oswald at the University of St Andrews, UK.