The Greatest Show on Earth

Richard Dawkins is a lousy philosopher, but he’s an awesome biologist.

I’ve never been very passionate about evolution. 10th grade biology plus some extra-curricular science reading convinced me it was an accurate explanation for the development of life. That allowed me to check that box on my “things I need to know” list and move onto other subjects I found more engaging, such as engineering, religion, and abolishing the abomination that is the designated hitter.

Over the past few years – and particularly when the Dallas Morning News Religion Blog was in full swing – I’ve found myself defending evolution against creationists, advocates of intelligent design, and other anti-science fundamentalists. At times I lacked specific information to be able to adequately respond. So I decided to read Dawkins’ new book: The Greatest Show on Earth – The Evidence for Evolution.

If you are interested in evolution, or if you want ammunition for debates, or if you want to give a gift of knowledge to someone who has doubts about the strength of the evidence for evolution, I highly recommend this book.

Unlike many scientists, Dawkins is an engaging writer. He knows he’s writing for the general public – he presents the scientific evidence, but avoids the jargon and minutia that bore even well-educated readers. Only one of thirteen chapters (the one on embryology) dragged a bit – the rest read easily and interestingly.

OK, enough general assessments, what did I learn?

Perhaps the most important thing I learned was one of the simplest. Each creature came from its parent(s) and genetically the child is almost completely identical to the parent. Clearly it is the same species. The parent came from the grandparent(s), and is clearly the same species. You can trace this line as far back as you want to go, back to the beginning of life. On a generation to generation basis, evolution is generally not noticeable. But on an evolutionary time scale, over millions of years (and sometimes much less) creatures diverge to the point where they are clearly separate species. This is usually expressed as different species sharing a common ancestor, which is plain enough. But the mental exercise of “walking backwards” through the generations made it much clearer to me.

This answers the creationists’ argument that there is a difference in “microevolution” (which can be seen in a human lifetime) and “macroevolution” (which the creationists insist doesn’t exist). The only difference in the two is the amount of time they take.

The commonality of animals is clear evidence of our common ancestors. Dawkins shows a skeleton of a bat – it needs no commentary to show the similarity to human skeletons.

If there was any doubt of the validity of evolution, DNA mapping has answered it. There is the frequently-quoted figure that humans share 98% of our DNA with chimpanzees, but it goes much deeper than that. To quote from the final chapter of the book “the evidence … is that the genetic code is universal, all but identical across animals, plants, fungi, bacteria, archaea and viruses.”

These are just a few of the highlights of The Greatest Show on Earth. Along the way, Dawkins counters most of the common arguments of creationists, and clearly demonstrates that evolution explains why our bodies are the way they are far better than intelligent design. Any designer who would create some of the weaknesses and inefficiencies in humans and other creatures isn’t very intelligent!

I’m still not very passionate about evolution. Ultimately, our primary question isn’t how we got here but what we’re going to do while we’re here. But now I understand evolution better than I did, and reading this Dawkins book was an enjoyable way to learn.