OSLO - Cockatoos can delay eating nuts in order to win
tastier ones, a surprise sign that birds can exercise self-control,
a trait usually seen as the preserve of animals with larger brains,
a study showed on Wednesday.
Scientists gave Goffin cockatoos, a mainly white species from
Indonesia, a nut while showing them a more attractive one just out
of reach. If the birds did not nibble the first nut for up to 80
seconds, they learnt they would get the second instead.
"Imagine placing a
cookie directly into a toddler's mouth and telling him/her that
he/she will only receive a piece of chocolate if the cookie is not
nibbled for over a minute," said lead author Alice Auersperg at the
University of Vienna.
"Only few,
typically large-brained animals have been shown to be able to
inhibit the consumption of an immediate food reward in anticipation
of a bigger one for more than one minute," the University said in a
statement.
The birds were
given pecan nuts, and all 14 of those studied waited for up to 80
seconds to win a more attractive cashew nut, according to the
findings in the journal Biology Letters.
A video showed one
bird, Muppet, waiting 40 seconds while strutting agitatedly around
a table top with the first nut in its beak before exchanging it for
a second.
Self-control in
human infants was studied in the 1970s in the Stanford Marshmallow
Experiment. Under that test, children were given a marshmallow and
told that they would get a second if they did not eat the first for
several minutes.
Commenting on that
test, the Vienna University statement said. "Interestingly,
children who were able to wait for the delayed reward showed
greater success in adult life than the ones who ate the first
marshmallow right away."
The ability to
trade depends on being able to suppress the impulse to eat the
first reward. It also requires a judgment on the reliability of the
trader and the relative costs of the delayed reward, Vienna
University said.
A scientist presents to a cockatoo hands containing a different
food reward in this undated handout picture released by University
of Vienna, March 13, 2013.
Scientist Isabelle Laumer is pictured with
cockatoos