In a recent Science article, , the so-called cultural intelligence hypothesis was tested and given support.
In a nutshell, this hypothesis is an answer to the “brain size problem”, which seeks an answer to the question of why the human brain is roughly three times the size of our nearest primate relative. The cultural intelligence hypothesis says:
To function effectively in the cultural world into which they are born, human children simply must learn to use these artifacts and tools and to participate in these practices, which require some special social-cognitive skills of social learning, communication, and “theory of mind” . Some other ape species transmit some behaviors socially or culturally, but their species-typical cognition does not depend on participating in cultural interactions in the same way as it does in humans, who must (i) learn their native language in social interactions with others, (ii) acquire necessary subsistence skills by participating with experts in established cultural practices, and (iii) (in many cultures) acquire skills with written language and mathematical symbols through formal schooling. In the end, human adults will have all kinds of cognitive skills not possessed by other primates, but this outcome will be due largely to children’s early emerging, specialized skills for absorbing the accumulated skillful practices and knowledge of their social group (so that a child growing up outside of any human culture would develop few distinctively human cognitive skills). Humans’ especially powerful skills of social-cultural cognition early in ontogeny thus serve as a kind of “bootstrap” for the distinctively complex development of human cognition in general
A competing hypothesis is the general intelligence hypothesis, which says that humans are more efficient at all forms of cognition such as memory, learning, perceptual processing, etc. However, this recent study gives strong support to the cultural intelligence hypothesis by doing a “systematic comparison of a representative range of cognitive skills among a single set of human and nonhuman primate individuals”.
The researchers did this by administering the Primate Cognition Test Battery to chimpanzees, orangutans, and human children of which has a primary division between “physical cognition” and “social cognition”.
The results were striking. On the physical domain, humans were statistically not much different, but on the social domain there was a stark gap between the human children and the other primates. From the article:
Young human children who had been walking and talking for about 1 year, but who were still several years away from literacy and formal schooling, performed at basically an equivalent level to chimpanzees on tasks of physical cognition but far outstripped both chimpanzees and orangutans on tasks of social cognition.