July 14, 2005 ‹ Chickens do not 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 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 it (the pain)
all-encompassing," said Siobhan Abeyesinghe, lead author of the study.
"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."
She added, "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
minimize psychological stress."
Abeyesinghe, a member of the Biophysics Group at Silsoe Research
Institute in England, and her colleagues tested hens with colored buttons.
When the birds pecked on one of the buttons, they received a food reward.
If the chicken waited two to three 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.
The study is published in the current Animal Behavior.
"In their natural environment it may pay to get food while you can,
before someone else does," Abeyesinghe told Discovery News. "But counter to
this, we found that when a much larger food reward was delivered for the
jackpot condition, hens chose it over 90 percent of the time, ruling out
that they have absolutely no awareness of the near future."
Prior studies have found that neuron organization 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. Abeyesinghe, however, did say, "They probably show more
cognitive ability than people would generally credit them with."
Raf Freire, a lecturer in the Centre for Neuroscience and Animal Behavior
at the School of Biological, Biomedical and Molecular Sciences in the
University of New England, Australia, agrees, but already suspected that
animals and birds, particularly chickens, had 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 told Discovery News. "Hence, it did not
surprise me that chickens show self-control."
He added, "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.