Like Humans, Chimpanzee Intelligence Depends On Genes
A new study has found no effect of either sex or rearing history on the cognitive skills of chimpanzees.
According to the study, chimpanzees raised by human caretakers performed no better on cognitive tests delivered to them by humans than did individuals raised by their chimpanzee mothers.
The new study considered data on cognitive abilities of 99 chimpanzees, from age 9 to 54. Researchers found that about 50 percent of the variation in the chimps' performance on a series of standardized cognitive tests could be attributed to genetic factors.
"As is the case in humans, genes matter when it comes to cognitive abilities in chimpanzees," said William Hopkins of the Yerkes National Primate Research Center, according to Science 2.0. "It doesn't mean that they are the only factor determining cognitive abilities, but they cannot be ignored."
Researchers said the findings of the analysis could add significantly to scientists' understanding of intelligence.
The study also suggested that differences in cognition may have arisen in the common ancestor of humans and chimpanzees about 5 million years ago.
"What specific genes underlie the observed individual differences in cognition is not clear, but pursuing this question may lead to candidate genes that changed in human evolution and allowed for the emergence of some human-specific specializations in cognition," Hopkins says. "It is also intriguing to consider what changes in cortical organization might be associated with individual differences in cognition and whether common genes might explain their common variance."
The study has been published in the Current Biology.