Many experts surmise that the shift from walking on all fours to upright had something to do with freeing up our hands to do other things, like transporting food from one place to another.
The Wall Street Journal
We had been dragging along across the tall grasses of the African landscape, me and the Missus, both of us carrying something on our back: in my case, a nice, juicy cut of a hyena, ripped from his/her/its (I can’t keep up with the pronouns these days) carcass before the lions got at it. Unlucky for them, I’d figured out how to grasp a rock in my paw with my new, bitchin’ cool opposable thumb.
In her case, little Grok, Jr., the apple of my eye–if you’re into fruits and nuts.
Every now and then we’d rise out of our crouches to look for oncoming predators, and to make ourselves look bigger, and more capable of defending ourselves. When I say “defend” what I really mean is “crush your skull before you crush mine.”
But to be perfectly honest, we were also trying to make ourselves more appealing to members of the opposite sex of the same–or similar–species we might encounter. Our average life expectancy was 37.8 years, about the time our descendants will start to “get serious” about fitness; hire a personal trainer, cut out the red meat (but not the wine), that sort of thing.
“Can we stop for a minute?” the Missus said. “Grok, Jr. is a growing boy. I can’t haul a mini-version of you around all day.”
“It’s not like I’ve got it any easier than you,” I said. “We’ve got three mouths to feed now, and I’ve got a week’s worth of hyena burgers on my back.”
“
That didn’t seem to mollify her. “A male may work from sun to sun,” she likes to say, “but a female’s work is never done.”
“Fine,” I said, setting down dinner and some of the other essentials we’d picked up at the barter economy store: gorilla milk, moss to wipe out . . . uh . . . tails with, the Neanderthal Enquirer. Hey, they put it right up at the checkout counter, it’s an impulse buy.
“You know,” the Missus intoned with that tone that said, Gertrude Stein-style, “you don’t know that you don’t know, don’t you?” After my thought bubble/interlude, she continued: “We could make better time if we just stood up and carried things with our front legs.”
“Legs aren’t for carrying.”
“Are so stuck in the Middle Pleistocene period that you’re not willing to try one teensy-weensy little new thing?”
“My father walked on all fours, and his father before him, and so on back to the beginning of time. Who are you to tell me to toss aside thousands of years of tradition just because you’re a little tuckered out?”
“Who am I? I’ll tell you whom!” And with that she thrust Grok, Jr. into my arms.
“He has gained a little, hasn’t he?”
“He’s in the 98th percentile for body weight, you dingbat,” she snapped as she fixed her hair. “While you’re going to be replaced by Homo sapiens if you don’t wise up.”