Dolphin Call Tells Calf Who's Mum
Female bottlenose dolphins whistle 10 times more often than usual after giving birth in order to help newborns recognise who is "mum".
The findings by a US team appear in the journal Marine Mammal Science.
These "signature whistles" are unique to each animal, allowing them to be used for identification.
Bottlenose dolphins are highly social; in their first weeks, calves encounter many adult females that they could potentially mistake for their mothers.
"The most obvious explanation for the increase in maternal signature whistle production is the need for the mother to be in contact with her calf," zoologist Dr Deborah Fripp from Dallas Zoo suggested.
"However, the decrease in signature whistle production of [dolphin] mother Lotty after three weeks does not fit this idea, especially as calves actually wander further from their mothers as they get older."
Instead, Dr Fripp said a likely purpose of this whistling enables a process called imprinting, whereby the calf learns to recognise its mother...
