Apparently we DIDN’T learn to walk because the primeval forests disappeared.
So why did mankind start walking upright? If seeing long distances on the savannah wasn’t a reason for change, but simply a benefit (and by itself it’s hard to see how that could be a survival-determinant, given the ability to see further simply by sitting on a rock), what other explanations could there be?
Theory One: Boobs.
<No image. Seriously, this is the INTERNET: go find your own boobs.>
Humans have buoyant boobs. It may not have been walking upright that improved survival chances so much as the ability to stand upright. In a pond.
Most animals are horribly vulnerable to ambush when drinking water: they come to the edge, put their heads down, and BAM! One visibility-impaired zebra-burger. But we do know that climate change and increased heat were factors: if your womenfolk can hang out in the pool, feed the kids, and keep an eye out for strangers with sharp claws… that’s potentially a winner. Going vertical means you can get further out and into deeper water than some of your terrestial killing machines may want to deal with.
- We don’t actually know how stacked Lucy was, and whether it would have made much of a difference.
- The whole crocodile thing.
Theory Two: Rocks
We don’t know an awful lot about what Lucy & Co. ate, but we’ve got a pretty good idea that she had a varied diet, and one thing we know is that pretty early in the game, and earlier than we initially suspected, meat got onto the menu. Contrary to the freaks over at PETA, it’s pretty clear that humans were never really into the whole “grazing vegetarian” thing, and that early humanoids who were didn’t make it. That means that either early man was really into murder-food, or that we were spending a lot of time around dead bodies.
Early man could throw rocks. Rocks may seem humble compared to other options….
…but rocks kill. Other creatures know this. If a dog is barking at you, raising a fist like you’re going to hit it won’t get a reaction. Making an angry face and raising your arm like you’re going to throw a rock at it, on the other hand, gets an instant reaction. In lots of dogs, this is a hardwired reaction, even if nobody’s ever abused them with rocks before. Somewhere deep in its little doggie brain is a little flashing sign that says “this is how the magic monkey kills you.”
Well, let’s say it’s early days, and you’re hunting for some small, inoffensive creature you can eat. Like a groundhog, savannah-squirrel, or “bird that got too close.” Who’s going to be the better hunter?
- The guy who can stand up for a moment and throw a rock?
- The guy who always stands up, and can throw two rocks without having to bend over and look for another one?
My money’s on MagicMonkey#2.
Downside: What did Monkey#1 hunt with such pitifully short range?
Theory Three: Agility
Maybe prior to Kubrick’s space-monkeys, we’ve got a period where we don’t know if MagicMonkey was actively hunting creatures, but we DO know that he was using rocks to get at marrow inside of bones. Don’t wince — that, with a vegetable and a stewpot, is basically what every granny on the planet serves you for soup.
That comes with a problem: you’ve got to dodge all the other creatures chowing down on that zebraburger. Eventually, they’ll leave the bones alone and you can get to them, but if you’re scrappy and quick, you could sneak away some bones that still have meat on them. That means more nutrition for you and yours.
Well, walking upright does come with a very significant advantage for scrapping around: a low moment of rotation. When you stand vertically, your horizontal measurement is pretty narrow. That means you can turn in place really fast.
If you can duck and dodge, then you stand a much better chance of coming away with something tasty, or maybe even catching one of those nasty vultures, and braining it with a rock. Hey, meat is meat, right?
You’re scrapping with a bunch of big nasty creatures for a bit of meat, and screwups hurt.