The web seemed to have exploded with news covering this hot-off-the-press open access Science paper, “Humans Have Evolved Specialized Skills of Social Cognition: The Cultural Intelligence Hypothesis.” Before I jump into the paper, here are some news sources wrote about this paper:

You really don’t need to read each one of the news sources, because they all are saying the same thing, human toddlers are more sophisticated in their social learning skills than their closest primate relatives. It is not that Earth shattering of a conclusion, even though the average human toddler brain How did the authors get to this outstanding conclusion?

Well first author, Esther Herrmann of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, and colleagues put 106 chimpanzees, 32 orangutans, and 105 young German children through a series of complex tests. The kids were around two-and-a-half years old and had been speaking for at least a year and the other non-human apes had all been made accustomed to humans.

Esther Herrmann Demonstrates TestThe tests were 16 different puzzles designed to weed out the differences in ability between humans and apes. Some of the puzzles included tracking the position of a reward under a cup, a very famous game that tests observation and concentration, and selecting the cup that the researcher pointed to, involved social skills such as communication. Esther demonstrates the test in the image on your right.

The results found that chimpanzees, orangutans, and human children were all generally equal the physical skills tests. But the human children were better at the social skills tests—scoring around 74 percent correct on the tests compared to scores of 33 percent from both groups of apes. I’ve attached Figure 1, from the paper, below for you to see how ‘significant’ human kids preformed better than chimps and orangutans in the social domain… and to be honest it isn’t that significant.

Herrmann et al., 2007 - Figure 1

You ask, “Why isn’t it that significant, Kambiz?” Well, do you see the bars above and below the gray boxes in the graph? Those represent the range of values the authors recorded, and in the social domain the human kids lowest range overlaps with the chimpanzee’s highest range. That kinda indicates that either their testing wasn’t thorough enough, i.e. they needed to increase the sample size or add another test to spread out the difference… OR that there really isn’t much of a significant difference.

But there is one example provided were human kids were way better. This test involved a human adult demonstrating how to retrieve food from a transparent tube by popping it open, and the children were almost always able to copy the action immediately and accurately and get the reward. Both ape species, by contrast, failed to understand what the experimenter had done, and instead tried to bite or tear apart the tube to get at the food.

Esther suggests that these tests document that higher social skills are uniquely human, and that it particularly applies to a concept known as “theory of mind” – essentially being able to see things from another’s point of view,

“Social cognition skills are critical for learning. 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.

The current results provide strong support for the cultural intelligence hypothesis, that humans have evolved some specialized socio cognitive skills, beyond those of primates in general, for living and exchanging knowledge in cultural groups. Young human children who have been walking and talking for about a 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 orang-utans on tasks of social cognition.

This was true at both the most general and the most specific level of analysis, for individuals never before exposed to these tests, and across the most comprehensive test battery ever given to multiple primate species.”

As you may know humans have the largest brains of all the primates and there are two main theories as to why humans have evolved larger brains than our other relatives. The first, called the “general intelligence hypothesis” suggests that humans’ bigger brains make us better and faster at all kinds of skills, such as memorizing, learning, and planning ahead. But the second, called the “cultural intelligence hypothesis,” suggest that larger brains have specifically enabled us to develop more complex social skills. Herrmann comments,

“This [study] contradicts the general intelligence hypothesis. We would have expected to see a difference in physical skills as well if the general intelligence hypothesis was right.”

That makes sense, our bigger brains enable us to cope with the complexities of social life… but that graph is still not significant enough for me to write one theory over the other.
Additional and related reading from two of the authors: