Joe Bennett: Why do we humans stand up? Birds do but their arms are wings

Look me in the eye and tell me your multiply-great grandparents weren't lizards, asks Joe Bennett. Photo / Getty Images

I fell. It hurt. But before we get there, fancy a bit of genealogy? Fancy a clamber through the family tree? Of course you do. We all like to know where we come from. So try this:

Stand on the bottom step of a staircase. Lean forward and put your hands on a stair roughly level with your shoulders. Bend your elbows. You're in the lowered press-up position but only about 30 degrees off the vertical. Now, without straightening your arms, simultaneously move your right hand and your right foot up one stair. Then do the same with your left hand and foot. Repeat till you've climbed the stairs. Then look me in the eye and tell me your multiply-great grandparents weren't lizards.

For you will have walked up that staircase in precisely the manner of every reptile you've ever seen David Attenborough coo over. Your frame is still articulated like the skink you glimpse in the summer grass, like the Komodo dragon, like the crocodiles of nightmare.

So what on earth are we doing standing up? Does anything else go on two legs? Birds, yes, but look what use birds have made of their arms. Some apes stand to grab stuff. Bears ditto. But we alone are full-time bipedal, terrestrial and vertical. We haven't even a tail for balance. It's a disaster.

Some apes stand to grab stuff. Bears do the same. Photo / Getty Images

Babies get it right. They crawl so are immune to falls. But it doesn't last. Hubris kicks in. Hubris, the pride that the gods will punish, makes them try to stand. The gods fling the babies back to the rug where they belong. But the signature note of hubris is resilience. The babes keep standing till they get the knack. And then they're away.

Standing's at the heart of our troubles. It raises our viewpoint. It lets us see into the next paddock, the next valley, the next continent, the next galaxy. And when we've seen we have to go. And standing frees our little hands. With no quadrupedal function, no corner to bolster, no weight to bear, our hands dangle in idleness. And the devil is famously drawn to idle hands. He offers them the juiciest employment.

In the Bible the arch catastrophe is the fall of man. In reality the arch catastrophe of man is his standing up. From there all things have sprung. We are the upright ape that overran the world.

The urge to stand doesn't cease. A friend works with old people. He dreads the late afternoon each day. For it is then that the wheelchair-ridden and hip-broken and demented all try to stand. He has to run to catch them, to put them back down before they fall. They pop up, he says, in the over-heated lounge, like so many mushrooms. The sad wrinkled babies.

So what on earth are we doing standing up? Photo / Getty Images

The will of the gods goes by the name of gravity. There's no place without it. It's always hunting us. And it wins every battle in the end. For gravity is a law of physics, and laws of physics don't give up.

I fell once in a hotel shower in Ras-al-khaimah. The shower was the bath. The toilet bowl stood beside the bath. As I fell I struck my head on the plastic seat on the toilet bowl and broke it. Had the seat been up I'd have hit vitreous enamel. I still feel nauseous at the thought.

This morning I went to visit an old man who loves to spoil my dog. On the way out the dog did a detour on to the front garden. As he turned I noticed that his offside rear paw slipped a little. No problem of course for the quadrupedal beast. But before I had had time to consciously register the slipperiness of the path and take precautions, my worn and treadless Croc slid from under me and I crumpled, my left leg somehow folding under the right and buckling like a pretzel.

We prioritise pain. Or rather pain prioritises itself. The loudest makes itself known. The quietest may not even be heard. So I got the message from my ankle, less forcefully from my knee, and not at all from my torn hand. Yet as soon as I'd decided there were no permanent threats to my wellbeing all I could hear was Mr Hubris telling me I'd got old and dropped my guard against the enemy of enemies. I felt guilty. I looked around to see if anyone had seen me fall.

And when I saw no one I heaved myself up, called the dog, and, feeling more shame than pain, I limped to the car and drove away to hide.