Cousins

Folks uncomfortable with the implications of evolution often say that it means we’re descended from chimpanzees. Recently in one of our southern states, parents sued a biology teacher because she was telling her class that evolution was wrong and that the real truth as to our origins was in the Bible. In her defense in court the teacher said that she had never seen a chimpanzee turn into a human, which says something about teacher certification in her state.

Chimpanzees are my cousins. Very distant cousins. By definition one is not descended from one’s cousins but we share a common ancestor. My first cousins and I share common grandparents, either on my mother’s side or my father’s.  I have eleven first cousins and I am happy to say that I’m in touch with all eleven mostly thanks to Facebook. Some might therefore read this blog. As an only child I really appreciate my cousins. I’m pretty sure that I have seven second cousins, but I’m not certain of the number. Again, I am very happy that I keep in touch with three of these second cousins, again thanks to Facebook and e-mail. We share a great-grandparent.

I have no idea about any third cousins, although they must exist, where we share a great, great grandparent -  two greats.  In his book The Ancestor’s Tale (2004) Oxford University biologist Richard Dawkins estimates that we humans are approximately 250,000^th cousins of chimps, and our common 250,000 times great grandparents lived approximately six million years ago.

I share some facial similarities and even mannerisms with some of my first cousins. My second cousin Steve however is almost twice my height; and I’m sure if I did meet any third cousin we’d not be recognizably related, except by a DNA study. So those worried about evolution -  you are related to chimps but not that closely, unless it’s in comparison to some other creatures.  Go back not just six million years and a quarter of a million greats, but 340 million years and very approximately 175 million generations, and we find that we are cousins with all tetrapods (four-legged creatures), including those who’ve subsequently lost their legs like snakes and whales, or turned their front legs into wings like birds, or arms like us. We’re all cousins. Perhaps this is why some people are vegetarians.