Humans see further by standing on the shoulders of giants. We build upon the cultures, skills, technologies and knowledge of past generations, in a way that other animals do not.
Many scientists have suggested that this cumulative culture depends on the size of our groups. The more of us there are, the faster our culture ratchets upwards in complexity. If our populations shrink, we lose skills and tech. We see this in theoretical models. We see it in past civilisations—Tasmania being the classic example.
And now, we can see it in two experiments. Working independently, two groups of scientists have shown that larger, more sociable groups are indeed better at maintaining complex cultural traditions, and even improving on them.
This might seem obvious, but people forget about it. As Joe Henrich, who led one of the new studies, told me, many scientists have assumed that Neanderthals were less intelligent than modern humans because they built less complex tools. The alternative is that they just lived in smaller, more scattered groups, and lacked the cultural ratchet that our ancestors had because of their big, connected societies.
As Henrich said: “For producing fancy tools and complexity, it’s better to be social than smart. And things that make us social are going to make us seem smarter.”
I’ve covered the two studies over at Nature News. Head over there for the details.