Schools for Scandal
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Forget Flipper,Dolphins in the wild can be dangerous bullies.
Gareth Huw Davies
Name this creature. It has a smile like a marine Mona Lisa
and a brain to qualify it for founder membership of Animal
Mensa. It welcomes passing swimmers like old friends.
Now try this one. It bellows, bullies and even kills. Marauding males "kidnap"
females and herd them out to sea to mate. One scientist describes joining
a group in the water as about as unpredictably dangerous as walking into
a fight in a pub.
The first answer, of course, is the
dolphin, a superior aquatic being. Give it time,
and it might evolve into something near-
human, if it didn't have more sense. And the second,
the aggressive lout? Well, actually, that's the dolphin, too.
By studying our favourite sea mammal in the wild, scientists have discovered
a darker, slightly shocking side to its nature. This week they confront
sentimental assumptions with hard facts in The Private Lives of Dolphins
for Equinox.
In the
Moray Firth in
Scotland, in waters as murky as strong tea ,lives a community of bottle-nosed
dolphins. Researchers have noted an aggressive, even murderous tendency.
Every year between 10 and 20 harbour porpoises are washed up with severe
internal injuries, bearing scars from teeth marks. Dolphins are almost certainly
the culprits. One theory is that they attack the porpoises because they interfere
with the dolphins' echo-location system.
Male dolphins have been seen jaw to jaw, zapping each other
with high frequency sounds.Scientists speculate that they may be using sound
to damage their opponent's
acoustic system.
Or perhaps they are just having
a shouting
match.
Elsewhere, here even more puzzling behaviour among bottle nosed dolphins
is being studied. In Florida, researchers have noted play sessions between
young siblings characterised by quite blatant sexuality, in which they
appear to break the usual taboo forbidding sexual relations within a close
family group. Why they behave in this way is not known.
Female dolphins normally go around in groups of up to four
generations, raising their young collectively. Males, on the other hand,
form pairs and stay together for life. In the waters off Western Australia,
scientists observed groups of non-related males colluding to abduct females
and take them off to deeper water to mate, in an apparent gang rape.
"The public has this image of dolphins as mythical, unaggressive and intelligent animals," says Dr Miranda MacQuitty, a researcher for the programme. "But they're wild animals, doing what they have to do, including committing violence, to survive in their environment. Scientists are only just beginning to unravel dolphins' social behaviour."
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