Friday, March 25, 2005

"The Beak of the Finch" by Jonathan Weiner

One of the critical points Creationists point to in their criticism of Evolution is that Evolution is still a theory: it hasn't been proven, and its processes have never been seen. Even though there are mounds of circumstantial evidence indicating that species arise and change over time, nobody's actually watched a new species being formed so Creationism is still just as valid a theory. Reading "The Beak of the Finch" was refreshing because it shows just how much real-world proof there is today of Evolution's processes. It turns out that when you observe species today, you find that evolution is still occurring, and at some times it occurs at a rapid pace. The principal driving mechanisms of the Evolutionary processes -- genetic variation between generations, and fierce natural selection (ie death) based on those relatively miniscule variations -- have been been proven to occur in today's species. Over generations of birds, insects, bacteria and the like, environmental changes can result in drastic changes in a species' appearance and functionality within 5 to 10 generations. Any Creationist claiming that species created at the beginning of time are unchanging are flat-out wrong.

What is interesting from the reading of this book, though, is that one sticking point of the Creationist argument has still never been proven. We have never directly observed one species splitting into two. We have observed species adapting over time. We have observed instances where there were one species, and then when we looked back later there were two. But we have never actually watched a species variate, split, and then evolve into two distinct species. We have all the proof of Evolution occurring, even down to the before and after pictures, but we have not yet watched it as it happened. It can still be claimed that although species vary and adapt widely to its environment, there is an invisible force keeping species from varying too much. So Evolution, despite the mountain of evidence supporting it, is still a theory. Creationism, despite the mountain of evidence against it, is also still a theory. This is not to say that they are equal -- and indeed, there is still the possibility that Evolution will be proved correct, because it is verifiable. There may be a study as robust as the ones the Grants made on the beaks of Darwin's finches that stumbles upon the direct observation of the Origin of Species.

A note on Evolution itself: Evolution is basically a process of breeding in the wild. Our genetic code is inconsistent between generations, both by accident and design. Variations occur throughout a population, and these variations make certain creatures more or less adapted to situations that may come up. Now, in periods of great environmental strain where there are limited resources, creatures end up dying. The creatures that had variations better suited for the crisis have a higher chance of living and hence having young that carry on the genetic line. But even when a death-filled environment is not culling the herd, variation is occurring. In fact, variation is constantly occurring. This is why when we look at fossil records, evolution seems to occur in spurts instead of gradually. Species are always changing, but there is only a high pressure to change in a certain way when the environment changes. That environmental change can be weather and terrain, the simple decrease of a resource, or the introduction of a competing species. And once again, while scientists have yet to observe a species being created in the wild, they certainly have watched hundreds of species die out completely. Some by our own doing, it should be noted. Natural selection is definitely occurring.