Reasons Why Evolution is True Part VI:
Homology

Although it makes sense to stick with a good idea when you’ve found it, you wouldn’t stubbornly stick to the same design even when it wasn’t quite working properly, would you? And yet this is just the pattern that appears in nature. Life on Earth shares a remarkable list of features, from protein-handedness and membrane structure to the DNA code. While some of these features, such as protein-handedness (which way around proteins are formed), are inconsequential, others are not. The genetic code is almost completely universal across all life. This is the reason GM can work, because a gene coded for in the genome of one species can be read by the translation machinery in another species’ cells. This does not necessarily have to be true, however, as the code is arbitrary and there are many possible configurations which would work equally well. Furthermore, the code is actually detrimental for some species living in extreme environments, since certain codes are more volatile than others. Despite this, the code is shared by all.

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Reasons Why Evolution is True

Across the next 10 articles, I present a few of the quirky examples of evolution that we can readily observe in nature. It is by no means an exhaustive list, but merely a set of stories which I feel illustrate well the power of evolution to create complexity, and how we can see evidence for natural selection by looking carefully at the idiosyncrasies it has produced.

The examples I provided in this series can be broadly categorised into a few themes; coevolution (Fig Wasps and Hawk Moths), evolutionary constraints on adaptation (Pandas, The Human Eye), convergent evolution (Birds and Bats), adaptive radiation (Galapagos Finches, Ring Species) and homology (DNA and the Pentadactyl Limb). And within each of these categories, there are numerous other stories I could have told to illustrate my point. But the point I am trying to illustrate is that evolution is a real phenomenon. Charles Darwin’s theory of evolution by natural selection is one which explains the natural world around us in both a satisfying and verifiable way.

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