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Dolphins 'sing' to their unborn calves in the womb
Dolphins never cease to amaze with their intelligence.
However, a new study has found they are even more like us than we previously thought - just as humans speak to their babies before they are born, and some very keen parents play their unborn children Mozart, dolphins have been found to 'sing' to their unborn calves.
Scientists have found mother dolphins teach their babies signature whistles before they are born.
Researchers from the University of Southern Mississippi observed mother dolphins performing a signature whistle for the baby in the months running up to the birth and up to two weeks after.
"It's been hypothesized that this is part of an imprinting process," Audra Ames, a doctoral student at the University of Southern Mississippi told Live Science at the annual meeting of the American Psychological Association.
It has been shown by earlier studies that mother dolphins start whistling a signature whistle much more in the days before birth - but they had never before studied signature-whistle rates not only before and after birth but in the same mother.
Ms Ames and her colleagues did just that by studying a baby dolphin Mira who was born to a 9-year-old mother at Six Flags Discovery Kingdom in Vallejo, California.
The researchers captured 80 hours of recordings of the mother, the calf and the five dolphins they lived with. It was important to study the five dolphins too, in order to understand whether the communication was exclusive to the mother and her child.
Scientists found the mother started increasing her signature-whistle production two weeks before birth - seemingly speaking to the unborn calf.
Similar behaviour has been found in humans, according to Ms Ames. "We actually do see that human babies develop a preference for their mother's voice in the last trimester," she said.
"We don't know if that's something that's going on here, but it could be something similar."