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Chickens worry about the future

Chickens don't just live in the present, but can anticipate the future and demonstrate self-control, something previously attributed only to humans and other primates, according to a recent study.

The finding, published in the current issue of the journal Animal Behaviour, suggests that domestic fowl (Gallus gallus domesticus) are intelligent creatures that might worry.

"An animal with no awareness of 'later' may not be able to predict the end of an unpleasant experience, such as pain, rendering [the pain] all-encompassing," says lead author Dr Siobhan Abeyesinghe.

"On the other hand, an animal that can anticipate an event might benefit from cues to aid prediction, but may also be capable of expectations rendering it vulnerable to thwarting, frustration and pre-emptive anxiety.

"The types of mental ability the animal possesses therefore dictate how they should best be managed and what we might be able to do to minimise psychological stress."

Coloured buttons do the trick

Abeyesinghe, a member of the Biophysics Group at the UK's Silsoe Research Institute, and her colleagues tested hens with coloured buttons.

When the birds pecked on one of the buttons, they received a food reward.

If the chicken waited 2 to 3 seconds, it received a small amount of food. If the bird held out for 22 seconds, it received a "jackpot" that paid out with much more to eat.

"In their natural environment it may pay to get food while you can, before someone else does," says Abeyesinghe.

"But counter to this, we found that when a much larger food reward was delivered for the jackpot condition, hens chose it over 90% of the time, ruling out that they have absolutely no awareness of the near future."

The clever life of bird brains

Prior studies have found that neurone organisation in chicken brains is highly structured and suggests that, like humans, chickens evolved an impressive level of intelligence to help improve their survival.

Unlike humans, the chicken brain has a remarkable capacity to repair itself fully after trauma, which has puzzled neuroscientists for years.

It remains unclear what exactly goes on in the minds of chickens, which are raised at a rate of 40 billion birds per year to satisfy human consumption demands.

"[But] they probably show more cognitive ability than people would generally credit them with," Abeyesinghe says.

Higher intelligence

Dr Raf Freire, a lecturer in the Centre for Neuroscience and Animal Behaviour at Australia's University of New England, agrees.

But he already suspects that animals and birds, particularly chickens, have higher levels of intelligence than currently thought.

"An ability to show self-control improves an animal's survival in their natural environment and would be expected to have been selected by evolutionary processes," Freire says.

"Hence, it did not surprise me that chickens show self-control.

"What is astonishing, however, is that the researchers were able to so elegantly and convincingly demonstrate this in chickens."

Both Freire and Abeyesinghe hope the findings will lead to more humane treatment of birds and animals raised for slaughter.

Aside from animal rights issues, other research has indicated that if a bird or animal feels stress before killing, that anxiety may adversely affect the quality, taste and texture of meats.