How The Rise Of Weaponry Led To Monogamy

Seems an unlikely agent of domesticity, but some scientists feel it’s the advent of assisted combat that really changed everything.

The reason? Weapons — rather than pure strength — allowed humans to overcome what the New York Times today terms “the brutal tyranny of the alpha male that dominated ape societies.” A rock, a spear, a catapult — these evened the playing field and placed a premium not just on ingenuity but on dexterity, too. And gave other males a fighting chance.

Bernard Chapais, a primatologist at the University of Montreal, feels the weapon was a key step in bridging the ape-human divide. It was a tool, in the form of a weapon, that made human society possible, in Dr. Chapais’s view — and not incidentally, was indirectly responsible for monogamy.

As soon as all males were armed, the cost of monopolizing a large number of females became a lot higher. In the incipient hominid society, females became allocated to males more equally. General polygyny became the rule, then general monogamy. This trend led to the emergence of a critical change in sexual behavior: the replacement of the apes’ orgiastic promiscuity with the pair bond between male and female. With only one mate, for the most part, a male had an incentive to guard her from other males to protect his paternity.

Knowing who their relatives are, humans were better able to socialize (since they knew how to avoid incest) and form extended family units. It’s only one component of Chapais’ research, but a fascinating one. And it’s disconcerting to think that one thing that sets us apart from animals — motiveless violence separate from any physical imperative — is, in a literal sense, part of what makes us human.