A Brandeis University researcher in Massachusetts has shown that an African grey parrot understands a numerical concept akin to zero.
Zero is an abstract notion that humans don't typically understand until ages 3 or 4.
Alex, a 28-year-old African grey parrot, lives in the lab run by comparative psychologist and cognitive scientist Dr. Irene Pepperberg. The parrot spontaneously and correctly used the label "none" during a testing session of his counting skills to describe an absence of a numerical quantity on a tray.
The discovery prompted a series of trials in which Alex consistently demonstrated the ability to identify zero quantity by saying the label "none."
The findings, published in the current issue of The Journal of Comparative Psychology, add to a growing body of scientific evidence that the avian brain, though physically and organizationally different from the mammalian cortex, is capable of higher cognitive processing than previously thought.
Copyright 2005 by United Press International
Explore further: Ancient Greek well yields rare wooden statue