Steve Jones was the former Head of the Department of Genetics, Evolution and Environment at University College London. His talk was a combination of examples of evolution, and ideas relating to the possible origin of language.
Steve starts the talk with two myths. One is, of course, Adam and Eve. The other was of the Chinese creation myth. This is where the god Pangu formed inside an egg, grew gigantic in size, broke from the egg, grew taller still and stretched the sky from the ground, and then died. From http://www.livingmyths.com/Chinese.htm:
Pangu died, and his body went to make the world and all its elements. The wind and clouds were formed from his breath, his voice was thunder and lightning, his eyes became the sun and moon, his arms and his legs became the four directions of the compass and his trunk became the mountains. His flesh turned into the soil and the trees that grow on it, his blood into the rivers that flow and his veins into paths men travel. His body hair became the grass and herbs, and his skin the same, while precious stones and minerals were formed from his bones and teeth. His sweat became the dew and the hair of his head became the stars that trail throughout heaven. As for the parasites on his body, these became the divers races of humankind.
Although Pangu is dead, some say he is still responsible for the weather, which fluctuates according to his moods.
Most of us in the UK may be familiar with the Adam and Eve Myth. However, to get a sense of how weird that story really is, it's good to look at creation myths that we're not culturally familiar with.
After the creation myth we are presented with statistics of the public acceptance of evolution. It's interesting but ultimately shows that a large percentage of people don't accept (understand?) evolution. According to the surveys, the problem resides mostly in Islamic countries (although the UK is far from immune).
So thousands of people deny the facts of evolution. Biologists accept and use evolution in a practical way, so why the disconnect? And where did the idea of evolution come from?
We are next shown the origin of species by Charles Darwin. However, the ideas contained within aren't entirely new. We are shown diagrams that were made to track the etymology of certain words in different languages. The diagram looks much like the tree of life used in biology. Just as Certain words have common ancestors, mutations, and similarities, we find the same in the natural world. Darwin didn't come up with this idea, it was already around. But he was one of the first to apply this thinking to biology.
Then we go back into exploring possible reason why people don't accept (or understand?) evolution. One possible explanation for dissent is that when Darwin first presented his ideas, many people saw them as dragging humans down to the level of animals. But why was the idea that Humans belong to the animal world wrong?
Gorilla DNA has now been sequenced and is 95% similar to human DNA. Chimps are 98% similar. Today it is undeniable that humans are part of the animal kingdom. But at the time of Darwin, it was argued that humans were made by god and were special. The argument continued to claim that if we are just animals, all of law and civilisation would crumble.
The talk gave many examples of evolution. The most interesting and obvious (when you're aware of it) is skin pigmentation. We were shown a map where the various type of skin pigmentation were plotted around the globe. However, it turns out that while humans are the only primate with varying skin pigmentation, they aren't the only species where this happens. Zebra fish also have interesting various in skin pigmentation depending on their location. And there does appear to be correlation between the location of human and zebra fish skin pigmentation.
The colour of our skin is primarily determined by melanin. Its the same for the Zebra fish. Having skin pigmentation protects us against nasty effects of UV light, and reduces rates of certain types of cancer, so it's a good thing for us. So why did some of us loose our pigmentation?
It turns out to be linked to the production of vitamin D. This is an important thing that we need. Without it, humans can experience difficulties in child birth, and babies can be born with rickets.
When our skin is exposed to sunlight it produces vitamin D. Having pigmentation in our skin acts as a natural sun block. In areas where there isn't a lot of sunlight, there is evolutionary pressure on losing this pigmentation so that vitamin D can be produced. If you have pigmentation in a countries with not a lot of sunlight, you are at a higher risk of vitamin D deficiency.
There were many other examples of evolution given in the talk. Steve wrapped things up by linking back to the idea of the origin of language. There appears to be a gene that is linked to the ability to understand language. Humans have it, but chimps don't. The gene seems to have appeared in our genome roughly 35 - 40 thousand years ago, which correlates with the origin of language. Is this gene essentially responsible for much of what we consider to be human traits?
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