Learning to Walk
Origins of Us - Bones
By the time we see Australopithecines like Lucy, we can be absolutely sure beyond a shadow of a doubt, that our ancestors were standing and walking around on two legs. And not only that, thery were committed to walking. It was their main way of getting around.
Giving up climbing for walking suggests that our ancestors were moving beyond the confines of the forest, that they were exploring new habitats. But walking is a physical skill that takes time to learn.
Just think about what babies have to do. Balancing on their tiny little feet, defying gravity. Some of us get the hang of it quicker than others. But most of us will, at some stage in our early childhood, stagger to our feet and walk. Each step involves coordinating some 200 muscles. Its an amazing feat of learning, but there are physical changes too.
As toddlers learn to walk, their bodies are changing. They're using their muscles in different ways, and the muscles will develop accordingly. And, deep inside their bodies, their bones are changing as well. They'll start to develop the backwards curve in the lower spine and the bottom of the spine will push down between the two hip bones. The hip bones curve forwards, and the thigh bone also starts to curve forwards and bend inwards.
But, what's really interesting is that we don't know how much these changes are programmed, and how much they're developing in response to walking.
Its obvious that the evolution of walking has had a profound impact on our bodies.
