German scientists say many species, not just humans, can draw inferences about the intentions of other individuals to cooperate in complex tasks.

Evolutionary psychologist Brian Hare at the Max Planck Institute in Germany says chimpanzees utilize social cues like eye gaze and face orientation to monitor others' behavior or infer motives of other subordinate or dominant individuals.

But while chimps aren't very good at drawing inferences about others' mental states, domestic dogs do quite well at such tasks. He says if one points to hidden food, dogs often grasp what is being communicated. In fact, he says, puppies even do it without prior training, indicating it is an innate ability, not simply one they acquire through contact with their owners.

Hare says domesticated dogs' ability to solve social problems might have emerged once the brain systems mediating fear were altered -- and the same thing may have occurred in human evolution. Chimps, he says, are constrained in solving cooperative problems by their impulse to fear more dominant individuals and behave aggressively toward more subordinate ones.

The research appears in the April issue of the journal Current Directions in Psychological Science.

Copyright 2007 by United Press International