By: Yimo Liu

When babies are born, their mothers usually speak to them in a high-pitched voice. The babies only respond to that kind of talking. Have you ever wondered if different species use that kind of voice to address their young? Well, dolphin mothers do.

They squeak in a sort of high-pitched voice which means “I’m here, I’m here!”. This lets their offspring know where their mother is.

Scientists have been doing some research about this high-pitched voice. They tracked 19 bottlenose dolphins down in Florida and put special microphones on them to prove that they were right about mothers using a different voice when they speak to the dolphin offspring.

Scientists declared that when dolphin mothers talk to the offspring, their voice has a larger pitch range, causing their voice to be higher pitched. “That was true for every one of the moms in the study, all 19 of them,” said biologist Peter Tyack, a study co-author from the University of St. Andrews in Scotland.

For more than three decades, scientists have been putting the special microphones onto wild dolphins. Young dolphins usually stay with their mother for an average of three years, so people have a larger window of data that the female dolphin they put the microphone on has offspring.

After finding plenty of dolphin mothers who speak in a high-pitched voice to their young, scientists could finally prove this: Dolphin mothers tend to speak in a more high-pitched voice than usual when they speak to their young, so their young can find them.