BOB HIRSHON (host):
Counting crows. I’m Bob Hirshon and this is Science Update.
People are experts at tallying up how many objects there are in a group. In the Proceedings of the National Academy of Sciences, University of Tubingen animal physiologist Andreas Nieder and his colleagues have shown that crows are also expert at it. He says the family trees of mammals and birds diverged three-hundred million years ago, from small-brained reptilian ancestors.
ANDREAS NIEDER (University of Tubingen):
But surprisingly, birds and mammals then independently developed higher end-brain centers that are now anatomically very distinct and different. Still, they are able to give rise to these very intelligent high-level cognitive capabilities like numerical competences.
He points out that sizing up how many items are in a group is helpful when evaluating food resources, and especially useful for social animals navigating coalitions of friends and foes. I’m Bob Hirshon, for AAAS, the science society.