Free The Incredible Human Journey by Alice Roberts Page A

it would drop to –40 degrees outside during the night), on a raised floor of slim larch logs. The stove
     occupied an off-centre position. Marina’s husband was sleeping somewhere else but he would dutifully come in periodically
     to check on the stove and replenish the pile of larch logs. We fell asleep in such warmth, with our faces almost roasting in the heat from the stove, that I stripped off most of my layers
     inside my down sleeping bag, but left them in the bag in case I needed them later in the night. I did.
    We awoke in a cold tent. The temperature inside the tents quickly dropped to match the ambient temperature outside as soon
     as the life-giving stove burned out. But before long Marina’s husband had coaxed the stove back to life and I could contemplate
     emerging from my sleeping bag and getting layered up, ready to step outside. It felt warmer again, but it was hard to tell
     if this was a real change in external conditions or if I was acclimatising to my new environment. Certainly, I was now out
     and about in –20 degrees, thinking how pleasantly mild it was, very different from my initial reaction to the same temperature
     when I had stepped off the plane in Yakutsk. But the Evenki were walking around in far fewer layers than their recently acquired
     and rather less self-sufficient companion. Many of the snowmobile drivers on the journey to the camp had kept their heads
     covered with reindeer hoods but their faces had been bare the entire way.
    Cold adaptation in humans is a tricky subject. It’s very difficult to be sure if what you’re looking at in terms of anatomy
     is an adaptation to, rather than a consequence of, an environment. Short stature and limbs certainly make sense in a cold
     climate as this reduces the surface area to volume ratio, making it easier to keep body warmth in. But short stature may also
     be the result of cold stress as the body is growing, in other words, a by-product of cold rather than an adaptation to it.
     Short limbs, though, may be a true anatomical-physiological adaptation to low environmental temperatures: something which
     is inherited rather than acquired as a child grows.
    In the 1960s the anthropologist Carlton Coon and others proposed that facial characteristics such as narrowed eyes, epicanthic
     folds, small noses and broad, flat faces – i.e. East Asian, or what were then described as ‘Mongoloid’ features – were specific cold adaptations, protecting the eyes and creating fewer projecting ‘corners’ to get cold. But at the other end of the landmass, large noses are put forward as cold adaptations in Neanderthals and modern Europeans, designed to warm icy air before it’s drawn
     into the lungs. And if East Asian features are cold adaptations, why haven’t northern Europeans ended up looking the same?
     The theory starts to look decidedly shaky.
    It seems unlikely to me that the environment could have been such a powerful sculptor of our bodies and faces when a fundamental
     characteristic of modern humans is the use of culture to buffer ourselves from such pressures. Being able to sew fur together
     to create protection from the elements would have been essential for the initial colonisation of northern Siberia, as it clearly
     still was for day-to-day survival in this extreme environment. Looking at the poor little girl who had ridden in on a sledge
     the same night as me, with an enormous chilblain blister on her right cheek, it was also clear that the Evenki were not immune
     from the cold. And, beyond intuition and anecdote, various researchers have presented anatomical and physiological evidence
     to show that East Asian faces cannot be the result of cold adaptation. Steegman published a series of papers along these lines
     in the sixties and seventies, including a report of a physiological study where he had compared the surface temperature of
     the face in Japanese and European people, at zero degrees, and found absolutely no