Saturday, May 01, 2010

Why Evolution is True Part 4

I'm about half way through the book now and one recurring theme that I'm liking is that the author (Jerry Coyne) will ask, "What would we expect things to look like if life evolved from earlier forms?" When you ask this you often find that the answer is exactly as things are now! Some examples...

We'd expect to find that earlier, extinct forms of life to occur before later forms in the fossil record and we do.

We'd expect to see 'imperfections' in design or outright bad design as evolution has to deal with the current model as minor changes are made. Things that are not needed and other bad designs would continue to show up. This is exactly what we see with numerous examples.

We might not expect this one but how else to explain the fact that many embryos display the forms of their very early forms. Humans embryos go through a 'fish stage' with gills and all. And interestingly all mammals go through a fish stage but no fish go through a mammal stage. Why? Because we descended from fish, the first vertebrae, and not the other way around.

You can also ask what would you expect to see if everything were created at once and is as is and has not evolved.

You would expect to see wild varieties of creatures with few if any common features. But you don't.

You'd not expect to find extinct creatures that are clearly earlier forms of the current version Why would you? But you do.

You'd not expect to see examples of 'bad design' of which there are many but you do. (As Robin Williams put it - "Intelligent design? You've got a sewage treatment plant right next to an amusement park!")

The stages that the human fetus goes through is especially interesting. Two examples: At about 6 months along the fetus grows a complete coat of hair called lanugo giving evidence of our close kinship to the rest of the monkeys. This hair is shed about a month before birth. Chimpanzees grow hair at nearly the same stage but they keep it. Also, a brand new infant will strongly grasp your finger if you gently stroke its palm. This is a remnant of our past as infant monkeys have to be able to hang on to their mother's fur. Humans (with very few exceptions) have no need to grasp their mother's fur but the hard wired behavior remains.

Finally, for today, a recurring ID argument for all this 'bad design' stuff is that the creator created things that way for maybe artistic reasons or for reasons that we cannot fathom. But the only thing that makes any sense of these bad designs is if things evolved from earlier forms. This means that the creator must have had in mind to fool legions of biologists just for fun. Not to mention the fact that the "the lord works in mysterious ways" argument is getting a little tired I think.

1 comment:

Sailor Sue said...

Your comment ... 'because we descended from fish' makes me think of "Your Inner Fish" - another great book about how evolution occurred.
Anxiously awaiting your Part 5.