Animal Behavior
Dolphins Use Baby Talk With Their Calves
Dolphin mothers vocalise to their calves—and it sounds a lot like baby talk.
Posted July 3, 2023 Reviewed by Abigail Fagan
Key points
- "Baby talk" towards children helps them learn how to speak.
- Scientists recently discovered that dolphin mothers change the way they vocalise when their calves are around.
- The scientists suggest that dolphin "baby talk" may serve the same function that it does in humans.
"Baby talk" is one of those human behaviors that may seem a bit silly on the surface but serves an important purpose: It helps infants develop their speech. Researchers have recently discovered that dolphins use baby talk, or—more accurately— child-directed communication, with their own infants (known as calves).
For a while now, we’ve known that dolphins have something akin to individual names. Each individual has a "signature whistle," which they call out to let others know that they are around. This would be like a human calling out their name as they walk through the door, letting their friends know who just walked in.
Working with a 34-year dataset of wild bottlenose dolphin calls, researchers analysed signature whistles of mothers when their calves were close versus when they were not. The researchers found that mothers changed their calls in a predictable way between these two contexts.
When mothers whistled in the presence of their calves, their calls reached higher frequencies and had wider frequency ranges. This mirrors the way that humans change our speech when speaking to infants. The researchers suggest that dolphin "baby talk" may thus be serving a similar purpose to human "baby talk": it may help infants learn how to vocalise.
The alteration in speech didn't just occur between dolphin mothers and very young calves, but also between mothers and calves that could be considered closer to "toddler" age. Again, this parallels human child-directed communication: we don't only "baby talk" with babies, but with all ages where kids are still learning to speak.
But do dolphins take as long as humans to learn how to talk, and thus could "baby talk" to older calves still help them learn how to vocalise? Indeed, the researchers explain that it may take dolphin calves years to learn the more complicated aspects of dolphin communication. Thus, this "baby talk" towards older calves may still be helping them learn the ropes of communication.
Child-directed communication hasn't been observed in many animals. This poses the question of why it happens in both humans and dolphins. The researchers suggest that it is because of specific similarities between us. Both humans and dolphins have long periods of development where we (1) are dependent on our caregivers for a long period of time, (2) live in complicated social environments and (3) must learn complex vocalisations from our caregivers in order to navigate these environments. That evolution may have sculpted the same behaviours between us both is perhaps not so surprising given these similarities.
The researchers remain cautious in the interpretation of their results, and explain that there are some possible alternative explanations for what they found. So, although the results suggest that dolphin mothers are helping their offspring learn how to vocalise, more research must be done before we can say this for sure.
Nevertheless, these findings give us some insight into the parallel ways evolution may have solved similar problems between species that are evolutionarily very distant from one another. And what a fun bonus that evolution’s solution seems to have come in the form of silly-sounding baby talk.
