Category Archives: Evolution

What made us human?

EJ has been learning prehistory and we are currently learning about early humans. We’ve recently discussed how Neanderthal people carefully buried their dead indicating that they interacted with members of their group in a way their ancestors did not. Early hunter-gatherer societies lived cooperatively not only within their group, but also across groups via trading of goods. Eventually learning to communicate verbally making cooperation easier.

This is rather different from other ape behavior which is much more territorial. Males in a group will typically fight off any non-member males that try to infiltrate the group. There is no cooperation between groups.

It would seem that something really important happened in these early human groups. What made early humans able to cooperate across tribes with relative ease?  According to a recently published paper, anthropologists studying modern-day hunter-gatherer societies have suggested that the way early societies interacted might have been integral to our uniqueness.

A major point in the study is that foraging bands contain several individuals completely unconnected by kinship or marriage ties, yet include males with a vested interest in the offspring of daughters, sisters and wives. This organization mitigates the group hostility frequently seen in other apes and also promotes interaction among residential groups, thereby leading to the development of a large social network.

“The increase in human network size over other primates may explain why humans evolved an emphasis on social learning that results in cultural transmission,” said Hill. “Likewise, the unique composition of human ancestral groups promotes cooperation among large groups of non-kin, something extremely rare in nature.”

Gwen Dewar, PH.D., writer of the blog Parenting Science discusses why this was so important in her article Living with inlaws made us human?!

Dewar contrasts this hunter-gatherer type society with later agrarian societies where patriarchal family groups are the norm and females are married to a male in another group.

Young brides get isolated from the only support network they’ve ever known. Surrounded by strangers and controlling in-laws, they lose autonomy and status. If they are abused, these women have no friends or family to come to their aid. Very often, they can’t even escape a bad marriage. After a divorce, a woman won’t be welcome in her husband’s community. And even if she has the resources to move away, she’ll be required to leave her kids behind…

A majority of agrarian societies were based on this idea of female relocation. How does this compare with hunter-gatherer societies?

When males spend their lives living in the same group, it means all their male kin live with them. The males living in other groups are unfamiliar—strangers. And when groups compete for resources, conflict is more likely than cooperation…

But the world looks different if men form domestic ties with their brothers-in-law. Let’s say that Jane is (still) married to Ted. That means Ted and Peter and brothers-in-law. And they all live together in Hollywood, so they’re committed to helping each other out…

And why is this a big deal? Go ahead and read the complete article on Baby Center.

What is fascinating for me, is how these early societies were perhaps more egalitarian and cooperative in many respects than we are today across nations. And to think we call them “cavemen.” We may more advanced than our hunter-gatherer ancestors, but clearly we could stand to learn a few things from their lives.


Hymn for Evolution