http://dsc.discovery.com/news/briefs/20050711/chicken.html
Discovery.com July 14,
2005
By Jennifer Viegas, Discovery
News
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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.
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