Some experts say that dolphins might be able to find a developing fetus inside a pregnant woman by using echolocation.
Dolphins send out sounds into their environment and listen to the echoes that come back. This helps them figure out what shapes and where things are. Doctors use a similar method to see how a human baby grows. Both use ultrasound, which are high-pitched pulses of sound that people can’t hear.
Lori Marino, a neuroscientist at Emory University in Atlanta who studies cetacean intelligence and thinks dolphins might be able to find a fetus, said, “I think it’s very likely that they could.” But, “you’d have to do a really well-controlled study” before you could say for sure, she cautioned.
Fetal buzz-ogram
From what people have said, it seems like dolphins are especially interested in pregnant women. People say that the animals swim up to the women who are pregnant and make buzzing sounds near their bellies. “Buzzing” is a type of echolocation that uses a lot of echolocation. When dolphins want to focus on something or get another dolphin’s attention, they buzz with their noses. “It sounds like a squeaky door,” Marino said. Here are the 10 most unusual pregnancies in the animal kingdom.
Malcolm Nicolson, a history of medicine professor at the University of Glasgow in Scotland, agreed that dolphins might be able to tell when a woman is pregnant. For example, a dolphin that swims with a female trainer before and after she gets pregnant “might well be able to detect a difference in her echo profile,” or the pattern of sounds returned by echolocation, said Nicolson. He also said that dolphins might be able to tell if a woman is pregnant even if they have never met her before. But Nicolson, who wrote a book about how obstetric ultrasound came to be, said that this was just a guess.
At least one study has shown that dolphins can see shapes through something like a box that blocks their view. Mike Walsh, an aquatic animal vet at the University of Florida, said, “It makes sense that they might be able to tell the difference between pregnant and non-pregnant people.” Walsh said that water is the best place for an ultrasound to work. Still, he said, it’s possible that the dolphins don’t realize that what they’re seeing inside the pregnant woman is a person.
Marino said that she thinks the dolphins might see a picture of the baby. “We know from other studies that they are very good at going from a visual image to an acoustic image and back again,” Marino said. Just as sonograms show people what their babies look like, echolocation might show dolphins what their babies look like.
So, it’s quite possible, Marino said, that dolphins can tell when other dolphins are pregnant. In fact, the animals have been seen chasing other dolphins who are pregnant. Marino said that dolphins use echolocation for many different things, like communicating with each other or correcting their young. He added, “They’re always buzzing!”
What dolphins can do
Dolphins probably don’t have the ability to use echolocation when they are born, but they learn it over time. Marino said that when dolphins are young, they babble before they learn to make more complex sounds. She thinks that they must have also learned how to use echolocation.
Even though dolphins might be able to tell if a woman is pregnant, scientists say it might not be a good idea to give birth near them because they eat meat and can be aggressive.
Some people say that dolphins can also diagnose or treat human illnesses, but Marino says that these claims are much less likely to be true. For example, dolphins have been said to act strangely around people who have cancerous tumors. But, Marino said, there is no proof to back up this claim and no proof that dolphins can use echolocation to heal people.
