Monkeys' memories impressive

Humans may have the biggest brains, but having 100 billion nerve cells between the ears is no reason for people to believe they're the only creatures capable of seeing the world as both real and abstract.

So-called "lower" animals, monkeys in particular, are pretty good at supposedly "humans only" skills such as counting and calculating as well as doing memory tasks as well as most human beings.

The latest study by researchers of cognition and behavior at Utah State University and Duke University in North Carolina has found that Rhesus macaques are showing they possess another capacity thought to be unique to humans — they count and sum combinations of what they hear and what they see.

In two experiments that essentially tested the hypothesis that animals in the wild use counting and sounds to assess situations and sum up threats to their territory, researchers found that animals can use sight and sounds in orienting themselves to situations. It's a capacity similar to a driver trying to determine if the number of cars in front at an intersection will make him miss the green light.

The animal won't see the symbol "27" representing the individuals counted, but the processes are similar and likely necessary to survival for both mankind and monkeys, according to findings published in the current issue of the journal Cognition.

The same researchers as well as other teams in Great Britain and Germany who study cognitive abilities of monkeys have revealed that the primates' brains are hard-wired for counting and that chimps outperform humans at certain memory tasks.

Results from the newest study led by USU psychologist Kerry Jordan found that macaques can not only comprehend numbers as images and sounds, they recognize the abstract qualities represented by them. The research provides more evidence that math isn't a humans-only skill.

The research provides further evidence that animals have these precursors to math "very early on in the evolutionary line and early on in development," Jordan said.

Jordan and Duke colleague Elizabeth Brannon trained two 8-year-old female macaques to tap out the number of dots of varying sizes they saw on a computer screen. With each dot that appeared, the animals heard a corresponding beep. They were trained to tap a square on the screen for each dot that flashed on the screen: If they saw seven dots, they would tap the square seven times.