"The earliest human ancestors, some kind of chimp-like apes, were living off raw plant foods and probably doing a bit of hunting like chimpanzees do now.
And then, somebody discovers the ability to control fire. Everybody argues about when this happened. We're saying it happened about 2 million years ago. Suddenly, all this food that was previously poisonous or indigestible becomes edible. We're talking about grass seeds, like wheat. And tubers. The amount of energy available to these early human ancestors goes up a huge amount. So, they get bigger. At the same time, their jaws get smaller, which is supported by the fossil record."
So where does the love come in?
Chimpanzee males are way bigger than female chimpanzees. But among early humans, males and females are roughly the same size. And we know that when males and females are roughly the same size, it's a sign of pair bonds, lifelong pair bonds. Male elephant seals are triple the size of females. Male gorillas are also much larger than females, and these animals are all polygamous. But male and female gibbons, for example, are the same size and have pair bondings. So, monogamy and same-sized males and females are linked throughout mammal species.
The same size? Not from what everybody else's research shows. Homo habilis and australopithecines were remarkably dimorphic. The dimorphism starts to even out with late Homo erectus, but not before. Time to run down some of the articles.
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