THURSDAY, Sept. 6, 2007 (HealthDay News) -- For those needing evidence that humans are brainier than the average ape, there's a new study showing that toddlers are better at "social learning," compared to adult primates.
When presented with a tube containing food or a toy, two-and-a-half-year-olds followed an experimenter's example to retrieve the prize, while the apes put all their energy towards simply biting or breaking the tube.
Humans differ from the great apes because their brains are about triple the size of their closest primate cousins. Human brains have also developed language, symbolic math and scientific reasoning skills.
The ability to learn by observing others enables human children to develop social and physical skills, say researchers reporting in the Sept. 7 issue of Science.
Researchers at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany studied 230 subjects, including 100 chimpanzees, 30 orangutans and 100 human children 2.5 years old. The participants were given the Primate Cognition Test Battery, which analyzes primate thinking and problem-solving in dealing with the physical and social world.
As part of one of the social learning tasks, the researchers demonstrated how to pop open a plastic tube to retrieve the food or toy inside. The children watched and copied the researcher; the apes attempted to break the tube or pull it apart with their teeth.
All of the subjects performed equally well in terms of the physical cognitive management of space, and in understanding concepts such as quantities and causality. However, the children were correct in three out of four of the social learning tests, while the two ape species were correct only one out of three times.
"We compared three species to determine which abilities and skills are distinctly human. The children were much better than the apes in understanding nonverbal communications, imitating another's solution to a problem and understanding the intentions of others," lead researcher Esther Herrmann said in a prepared statement. This is the first study to compare the performance of toddlers and apes on cognitive and physical tests.
The researchers chose to test human children at two and a half years old because that is when their physical skill level most closely resembles the skill level of a chimpanzee. The apes ranged between three and 21 years old.
According to the researchers, the results of the study support the theory that human social skills give humans an evolutionary edge. A second theory argues that humans differ in skill levels from apes as a result of being generally more intelligent.
For more on early childhood development, head to the American Academy of Pediatrics.