DURHAM, N.C. -- A new study representing the largest study of animal intelligence to-date finds that animals with bigger brains and broader diets have better self-control.
Published this week in the journal Proceedings of the National Academy of Sciences, the study is part of a long history of research aimed at understanding the animal mind. Specifically, why are some species able to do things like make and use tools, read social cues, or even understand basic math, and others aren't?
Until now, most studies of animal intelligence have focused on only one or a few species at a time, explained co-author Evan MacLean of Duke University. But MacLean and other researchers working at the National Evolutionary Synthesis Center came up with an idea: if they could convince enough animal experts across the globe to conduct the same set of experiments, they could test ideas about how cognitive differences in the animal kingdom came to be in a much more rigorous way that wasn't possible before.
Working with nearly 600 animals representing three dozen species of birds and mammals in zoos and research facilities worldwide -- ranging from wolves in Austria and jays in the U.K. to spider monkeys in Mexico -- the researchers put the animals through two tests designed to measure "inhibitory control" -- a measure of brain function associated with the ability to control impulses and delay gratification. Most animals don't have to worry about buying one too many drinks or avoiding the all-you-can-eat buffet. But the ability to exhibit self-control could help animals wait for just the right moment to pounce on their prey, for example, or share food with relatives without first eating it all themselves.
In one test, researchers hid a piece of food in an opaque plastic cylinder made from a 2-liter soda bottle, and trained the animals to retrieve the treat by reaching around to one of the open ends. Then they switched out the opaque
|Contact: Robin Ann Smith|
National Evolutionary Synthesis Center (NESCent)