the wild you

By my own request, the snowcats deposited a colleague and myself in a hut on the Antarctic ice fields and drove away to the coast. Our abode was little more than a container on a sled with a small petrol motor for heat.

For several days, until the snowcats returned from their supply run, the nearest living thing was more than 130 kilometres away. No birds, animals or even bacteria. The temperature was a steady -15, the sky was blue and the ice dead flat to the horizon in every direction. A whiteout blizzard was predicted and did eventually arrive but right then the silence was profound.

We were alone in one of the most inhospitable places on earth, perfectly happy with good clothing, warm beds and a refrigerator to keep our food warm enough not to freeze.

Sitting on the roof of the hut in that vast white emptiness made me realise what remarkable mammals we are. We can live in tropical rainforests, deserts, stacked on top of each other in cities and here on the planet’s most profound ice mass. As someone once said (was it EO Wilson?), we’re pan-niche monkeys, able to survive almost anywhere. It’s a skill we share with bacteria and it has allowed us to multiply like a virus in full bloom – but let’s not dwell on that discomforting metaphor.

The time it has taken to make eyes that can perceive light, skin that can feel the world around it, a thumb without which civilisation would probably not have been possible and a brain seething with trillions of synapses is almost incomprehensible.

But it happened – and here you are, reading these squiggles called writing, which you fit together to make sentences. And from them, you’re making a picture similar to the one in my head. Hello, fellow Homo sapien. Take a bow. You’re one of this planet’s most amazing inventions.

The feral inner you

Until very recently humans were thought to be islands of biological efficiency, gathering oxygen, processing food and getting on with the business of living. Our cells attacked germs and kept us safe from dangerous pathogens.

In the last few years, however, researchers have discovered that we’re a social network. In fact, most of what we are is not human at all, but a wacky ecosystem of bacteria that outnumber our cells 10 to one. And much of it is truly wild.

For a start, you can be sure that about 20 per cent of the genetic information in your nose and half the residents in your stomach are unknown to science. It’s related to stuff being dubbed biological dark matter. The truth is that you’re only 1 per cent human and 99 per cent bacterial. If you want to retain a strong sense of identity, read no further.

The reason all this wasn’t discovered years ago was because people in white coats staring into microscopes were generally looking for harmful bugs and ignored all the other stuff on their slides. The idea of benign microbes never crossed their minds. But increasingly accurate and ultra-fast gene sequencing equipment has changed all that.

‘Just because microbes are foreign and we acquire them throughout out life,’ writes Jennifer Ackerman in Scientific American, ‘doesn’t mean they’re any less a fundamental part of us.’ By sequencing the genes in this microbial soup, scientists are creating a catalogue of just who we are and of the non-us bacteria called commensals.

Let me introduce you to most of what you are. Bacteria are the oldest living organisms on earth – they’ve been around for billions of years. They’re single-celled microscopic organisms with one tiny DNA strand and they reproduce by dividing. Right now there are about 10-trillion in or on you as you read this (don’t scratch).

Babies are born bacteria free and pick up their first useful batch in the birth canal. After that the commensals come thick and fast – through mother’s first kiss, the sheets of the cot, breast milk and all the cooing relatives and friends. After that, their bacteria multiply exponentially.

We couldn’t survive for long without them. They create the enzymes necessary to make vitamin B12, convert carbohydrates in things like potatoes, apples, oranges and wheat into usable glucose, regulate the flow of stomach acid, orchestrate our appetite, influence stem cells in the manufacture of fat, muscle and bone and many other things still under research.

The puzzle is why our immune system lets all this happen. You’d think it would distinguish between the body’s own cells (self) and non-self – and boot out the interlopers. Why this doesn’t happen is still a mystery.

Research going on at Caltech in California suggests that bacteria actually strengthen our immune system and fight infection. Some evidently prevent our bodies from mistaking ‘self’ for ‘other’ and attacking, causing auto-immune disor­ders such as Crohn’s disease. A problem, says Ackerman, is that things like antibiotics, useful as they are, are taking out the good with the bad. And one of the good bugs is Helicobacter pylori, which tells us to stop eating when we’re full, the absence of which could explain rising obesity levels.

If you think all this is odd, it gets odder.

Molecular biologist Bonnie Bassler, who teaches at Princeton University in the USA, has discovered that bacteria ‘talk’ to each other on a micro equivalent of Facebook. If your sushi suddenly starts to glow in the dark, she has found the answer.

Being such simple organisms, she wanted to know how they could do anything at all. They seemed too small to have an impact on their environment – unless they acted in synchrony. Could they be communicating?

The bacteria that create marine bioluminescence seemed a good place to start. They only create light – instantly and all together – when they reach a certain density. How do they know the right moment? What Bonnie found is that they talk with a chemical language, constantly sending out molecular signals. When the molecules reach a certain density, wham, they light up.

Certain shallow-water squids, she found, have pockets of these bacteria on the under-part of their bodies which turn on at night to prevent a moon shadow, which would alert predators to their presence. They turn off the light in daytime by ejecting most of the rapidly multiplying bacteria, which then switch off. They’re the stealth bombers of the ocean. The switch mechanism is called quorum sensing.

This is a force for good and bad. Because the bad bacteria are so small and you’re so big, they couldn’t make you ill acting independently so they multiply under the radar of your defence system. Then, in a private language, they send out the command to attack.

But, to be effective, they need to know what other bacteria are around. Bonnie’s team went back to their microscopes and found that bacteria also have a multilingual, inter-species language, a sort of chemical Esperanto. They know who’s around them and they can count. This way they make things happen, like us for instance.

‘Bacteria have been around for billions of years and humans for only a few hundred thousand,’ she says. ‘We think they made the rules for multi-cellular organisation. They can say ‘me’ and can say ‘you’. That’s how our bodies work; how a heart doesn’t become a lung or skin or a brain.’

So, in a way, its bacteria which invented most of what we are. Humans just added a few bells and whistles to become Homo sapiens.

The future of medicine, of course, would be to create language that inhibits the communication of bad bacteria and improves chatter among the good ones. Right now that’s what’s being done. The future of health care is about to take a quantum leap.

The art of walking

The word saunter isn’t used much these days, probably because so few of us do it. Instead we march. The dictionary links sauntering to words like amble, meander, drift, mosey and, my favourite, tootle. It is probably derived from the French sans terre, meaning ‘without land’ or simply ‘drifter’.

The great American wanderer Henry David Thoreau, who cut loose from civilisation to live in the woods beside Walden Pond, had little time for those who didn’t do it:

‘He who sits still in a house all the time may be the greatest vagrant of all, but the saunterer is no more vagrant than the meandering river, which is all the while sedulously seeking the shortest course to the sea.’

Sauntering implies a way of walking (just tootling along) but also an awareness of actually walking. And that awareness was evidently once vitally important to us as a species: our feet have more nerve endings per square centimetre than anywhere else on our body.

‘Your feet are designed to feed multiple information to your brain,’ said podiatrist Chris Delpierre when I tracked him down at the Sports Science Institute in Cape Town. ‘They check the surface you’re walking on, the temperature, gradient, grip and balance. So obviously the best way to walk is barefoot or with a minimalist shoe. If you lock up your foot in a boot you blindfold it.

‘We’ve lost the art of barefoot walking. Our ancestors had hard feet and could run on them all day. But our feet have evolved. They have much softer skin. And because of shoes we walk differently.’

Together with biokineticist Avi Prasad, Chris explained why by slipping off his shoes and waggling his toes. ‘Your foot is designed to bend and when this happens it does two very different things milliseconds apart. On contact with the ground your heel acts like a turd from a tall cow and blobs. As soon as you roll forwards the tendons go soft allowing the bones to spread and your foot to widen.

‘A fraction of a second later it has to become rigid and it does this when your big toe hits the ground. This tightens your foot bones which become a lever for forward motion.

‘So if your foot doesn’t bend, it remains a soft, squidgy thing which loses its power as a precision device for walking on. That’s what happens in a rigid boot.’

The motion of walking is the biokineticist’s department: ‘As your foot bends,’ Avi explained, ‘the load chain goes through your ankle, up your leg into your knee and hip, which all start to take more weight. If you don’t have that signal from your big toe, your load transfer is going to go somewhere else. This will change your movement dynamics – and that’s when injuries can happen.’

Marguerite Osler, an Alexander Technique teacher, became so concerned about people stomping and shuffling around that she wrote a book to help them walk. The Art of Walking is more poetry than prose and more Zen than science, but is a lyrical plea to take off our shoes and live. There are, she says, three causes for our crippled locomotion: fashion, the cult of exercise and a tradition of military marching.

‘Women have had the worst of fashion,’ she said, also wiggling her bare toes at me. ‘Men’s fashions have always been more sensible, but women’s fashion shoes are manufactured to make money and not aid walking.

‘Sports shoes can be much better, but the fitness ethic is to go further, hammer harder and push to the limit. That’s bad news for feet. Then there’s our required bearing; upright, proud, elegant and … well, military. Children don’t walk like us. We start strutting around as teenagers and never stop. Good walking is effortless, springy, quiet and gentle on the body. It’s a glide. That way you can walk forever.’

So should we all be going barefoot or in floppy takkies? Chris shook his head. ‘It’s not as easy as that. Barefoot walking requires constant awareness. If you’re a younger person or you hike a lot or trail run in the mountains, your best bet is to stay as fit and agile as possible and wear as little shoe as you can.

‘It’s a compromise of course. Barefoot or with minimalist shoes you risk thorns, stress fractures and even scorpion bites, but your whole system will function more efficiently. But when you get older or are a weekend warrior and pad around the office all week, you need to step out into the wilds with a good, supportive boot and a trekking pole. Especially if you’re carrying 20 kilograms on your back.

‘Something like one tenth of everyone who ends up in a hospital emergency room the world over is there because of a twisted and sprained ankle. It’s our weak point and that’s what a boot prevents.

‘But on average most of us walk around 8 to 10 kilometres a day on perfectly flat urban surfaces. We’d all be in much better shape if we did that barefoot, or with as little as possible on our feet.’

He wiggled his toes again and I had to admit, they did look very happy being free. I could easily imagine them on an amiable saunter.

Becoming bipedal

This morning you rolled out of bed and did one of the most confounding things known to palaeoanthropology: you stood up.

Several million years ago when your ancestors did that, they should have been immediately spotted and eaten. At about the same time proto-humans lost their scary canines and hadn’t yet invented tools, so they couldn’t defend themselves.

Evolutionary pressure got it right. But how on earth did we become vertical, bipedal, fangless, hairless – and survive? The greatest minds in the business of digging up old bones admit they simply don’t know. But theories abound.

One is that we were forced onto the African savanna by declining forests and stood up to see over the grass. But that’s been debunked because the fossil record shows we never lived there but on the forest edge.

Another theory is that our pre-human ancestors took to the water, becoming aquatic apes. You don’t need hair in water and we have more fat under our skin than all other land mammals. We can also swim better than any other primate and our nostrils are built so we don’t take water when we dive. But no, the fossil record shows huge crocs in the Rift Valley lakes where we are thought to have begun.

It is possible that we stood to show off our sexual organs for appraisal – a man has twice a gorilla’s tackle and a woman has the biggest breasts per body size of all mammals. Blatant peacockery. But you don’t need to walk to do that.

There’s an even more interesting theory. A specialist on biomechanical locomotion, Owen Lovejoy, suggests that bipedalism is related to co-operation and increasing monogamy. It was far safer for an early hominid mother to stay home with the kids while the males went hunting for food.

All other primates eat what they find, but to bring food home requires the ability to carry it, and walking on two legs makes that possible. Females would select for males who lost out in the warring stakes because of poor dentures and who therefore co-operated with them and other males in order to survive. To do that they needed to become bipedal.

Their young survived better under this arrangement, emulated their parents and went on to conquer the world. Our first tool may not have been the hand axe but the shopping bag.