Sunday, April 25, 2010

Why Evolution is True

This is the title of the book I'm currently reading by Jerry A. Coyne. It is a wonderful book and rather than write a review after I'm done I think I'll jot down some of the more interesting things as I read them. Helps me to understand too.

First some depressing facts from the introduction:

"Human beings, as we know them, developed from earlier species of animals." To this statement only 40% of Americans said it was true. The only country to do worse was Turkey with 25%. Turkey is rife with fundamentalism as is America. Europe in general answers about 80% true as they do in Japan.

1 in 6 US teachers believe that God created human beings pretty much in their present form with the last 10,000 years.

Classification and the watch fallacy.

The watch fallacy from the 18th century Englishman, William Paley, is an old argument that goes like this: Let's say you're walking along the beach and you come across a pocket watch. Upon inspection (you take the back off) you find that it is finely crafted and perfect in every way for what it does. Clearly this was designed by some intelligence - a master craftsman - and didn't just pop up from prehistoric ooze. The observation that many animals are perfectly crafted for their environment suggests a master craftsman designing them and us.

Long before Darwin, scientist were busy classifying the flowers, trees, and animals. Many different civilizations did this and yet they all came up with basically the same classifications. You have things with backbones and things without. Inside the back bone guys you have things with fur or things with scales. Etc and so on. In other words there is a natural logic to the classification that is obvious to anyone doing the classifying.

If each creature were designed to be perfect for their environment then why are there so many common features between dissimilar animals and dissimilar environments? If each thing were a design separate from the other then the animals would be like a collection of matchbooks (the author's example). You might be able to classify the matchbooks by color, or size, or from where they came but all of these classifications are equal to each other and suggest no real logic.

On the other hand if we ask the question: What would you expect the classification of animals to look like IF animals evolved from earlier forms of animals? - you would get something exactly as we find it! This is true with the animal kingdom as we find it and continues to be true and is further supported by the fossil record of earlier forms of a variety of animals.

Not to mention, not all of the 'designs' are so perfect. Evolution has to work with what came before. It might be helpful for a turtle to have 6 flippers instead of 4 but evolution is stuck with making improvements on the quadruped now and doesn't start all over with every mutation. Why do men have breasts? Why do we have appendixes? Men's testes start up in their abdomens and move down through a tube at the age of a few months. This trip weakens that area of the body and is exactly why men are prone to hernias. This is a compromise. Keeping the testes cooler outside the body makes for more sperm production at the expense of making us susceptible to hernias. What master craftsman would make such a design?

2 comments:

Sailor Sue said...

And so maybe the 'master craftsman' isn't so masterful! I know there are some believers out there that also think evolution is the masterplan. How might they explain this dichotomy?

Scott said...

I think this falls into the "Who cares?" department. If a theist wants to believe that God created evolution or the Big Bang for that matter, so what? I'm bothered by fundamentalists INSISTING that 'creation science' be taught in the science classroom when there is zero foundation for this kind of thinking being anything akin to science and just an obvious ploy to get religion taught in the public school.