Dolphins
whistle 'hello'
Posted
at BBC News
By BBC News Online's Anne Lavery
Wild dolphins greet each
of their pals using individual whistle signatures.
Until
now this sort of behaviour has only been found in birds
and humans.
Previous
research with captive dolphins shows that each one has
a unique whistle and can mimic another dolphin's whistle
perfectly after hearing it just once.
Biologist
Dr Vincent Janik at the University of St Andrews in Scotland
decided to investigate how bottle nose dolphins interact
in the wild.
He
recorded nearly two thousand whistles from dolphin colonies
off the Scottish coast.
So
as not to disturb the dolphins with noisy boats, he used
six underwater microphones and a computer-based method
for locating individual vocalists. Human listeners then
identified matching whistles.
First
step to language
Dr
Janik concluded that the dolphins were responding to each
other by mimicking an individual's call back. Such interactions
with learned signals are thought to be a first step toward
the evolution of real language.
Communication
between dolphins seems to be quite sophisticated yet no
one really knows what they say to each other.
In
his report published in the journal Science Janik said
that the dolphin's greetings might not necessarily be
a simple friendly "hello"; they could equally
be an aggressive warning.
Copyright
© BBC News
Reprinted from http://news.bbc.co.uk/1/hi/sci/tech/894944.stm
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