This year is the 200th anniversary of the birth of Charles Darwin and it has been 150 years since the publication of On the Origin of Species. I read the book when I was 12 or 13 and followed it up with The Descent of Man. It's likely I had encountered the idea of evolution before this but I can still recall, thirty years later, how astounded I was with the weight of the evidence presented and especially the enormous explanatory power of his ideas.
The fact that all the amazingly diverse life on earth shares a common ancestry seems difficult for some people to accept but I find it inspiring. Darwin was a master at discovering and illustrating the patterns in the forms of life he observed. His theory of evolution is an excellent example of the power of simple iterated processes to generate both great beauty and complexity.