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Wednesday, 22 May, 2002, 12:44 GMT 13:44 UK
Evolution of supercats
But now a US psychologist has come up with evidence that nature is giving a helping hand.
He says cats have learned what buttons to press to please their owners after 5,000 years of living with us. Apparently, it is all down to the miaows they choose to get what they want. The rewards are clear - more pampering, tastier food and a seat in the comfiest chair. But not all scientists are convinced. Dr John Bradshaw of Southampton University, UK, says there is no doubt that cats are good at handling humans. But he says there is no evidence to suggest that artificial selection is taking place. The term was coined by Charles Darwin to explain how man has shaped plants, crops and domestic animals by selective breeding. Learned response "Cats learn to miaow in ways that manipulate their owners but it's got nothing to do with evolution at all - it's a learned response," says Dr Bradshaw, an animal behaviourist. Many cats seem to have a set of miaows they use for different contexts, he says. For example, a cat might choose a particular noise to signal it wants to be let out and a different one to demand to be fed. But when you compare cats, there is nothing in common between these miaows, he says. This suggests that each cat learns how to get its owner's attention, something that is nothing to do with genetics. "There's a much more plausible explanation," Dr Bradshaw told BBC News Online. "Each cat tends in its own lifetime to learn the noises that interest its owner." The controversy arises from a Cornell University evolutionary psychology study.
He played the cat calls back to 26 human volunteers and asked them to rate each one for pleasantness and appeal. The same set of sounds was played to a second group of volunteers who were asked to rate how urgent and demanding the miaows were. Humans seem to be able to distinguish between longer, raucous miaows and softer, more pleasing ones. An urgent or demanding call is "the kind we hear at 7 am when we walk into the kitchen and the cat wants to be fed," says Mr Nicastro. "The cat isn't forming sentences and saying, specifically, 'take a can of food out of the cupboard, run the can opener and fill my bowl immediately', but we get the message from the quality of the vocalisation and the context in which it is heard," he adds. Fickle humans Mr Nicastro, who owns two cats, goes further. He says the pleasant sound is the one a cat might use, say in a rescue centre, to ask to be taken home. More demanding calls could cause a feline to be left behind to face an uncertain fate. The psychologist says humans have long been selecting for the most pleasant sounding cats. "Seven thousand years ago, when we think the ancestors of our domesticated cats began wandering into Egyptian granaries and offering to trade rodent-control services for shelter, it was probably the pleasant-sounding cats that were selected and accepted into human society," he says.
Although it might be possible to select for certain vocal abilities in pedigree cats, there is no evidence that this is actually happening. "In ordinary domestic moggies, they go out and select their own mates," he told BBC News Online. "The idea that a female would go up to a male in a back alley somewhere and say, 'could I hear your miaow to see if the kittens you father will be appealing to people', couldn't happen. Cats don't have that level of communication." But that conclusion is unlikely to satisfy Mr Nicastro. "Cats are domesticated animals that have learned what levers to push, what sounds to make to manage our emotions," he says. "And when we respond, we too are domesticated animals."
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