Friday, December 21, 2007

Evolution In Action

I hear all the time that “we see evolution happening.” When people say that, they don’t mean we see all life having descended from a supposed common ancestor. They don't even mean we see one kind of animal becoming another kind of animal (i.e. reptiles becoming birds). They mean to say we see natural selection occurring all the time. But since they call both “evolution,” they blur the distinction between the two. Here’s an example:
"Countering the widespread view of evolution as a process played out over the course of eons, evolutionary biologists have shown that natural selection can turn on a dime -- within months -- as a population's needs change. In a study of island lizards exposed to a new predator, the scientists found that natural selection dramatically changed direction over a very short time, within a single generation, favoring first longer and then shorter hind legs." Sciencedaily
Note how they use both terms - evolution and natural selection - when discussing this example. First, let me say, this has got to be the worst example of evolution that I've seen. If it weren't in Sciencedaily, I would have thought it was a joke. For being zealous evolutionists, they don’t seem to understand evolution very well. You see, individuals don’t evolve – populations evolve. It’s supposed to be “descent with modification” (Evolution 101). Yet here they are talking about changes “within a single generation.”

Here’s the gist of the Sciencedaily’s article. On a group of 12 islands, there were indigenous lizards that had no predators. On 6 of the islands, scientists introduced a larger, predatory lizard that would eat the smaller ones. To escape being eaten, the smaller lizards would climb into trees and bushes. After 6 months, scientists compared the smaller lizards on the 6 islands with the predators to the smaller lizards on the 6 predator free islands; lo and behold the lizards on the islands with the predators had shorter legs than those on the islands without predators. It seems those with shorter legs were better able to climb and escape being eaten. Now, I ask you: is this evolution?

Suppose I have a population of mice – some white, some gray. Being the heartless soul that I am (just ask any of my critics) I want to see if this population can evolve so I do an experiment - I arbitrarily kill every gray mouse. Wow, it’s true! Evolution does happen! I now have a population of white mice in only one generation!

Now back to the lizards: on the islands with the predators, the lizards that climbed well (short-legged ones) survived and those that climbed poorly (long-legged ones) were eaten. After 6 months, there are more short-legged lizards left. Duh! I hope these scientists aren’t getting a government grant for this stuff because I’d hate to see my tax dollars supporting such a sophomoric experiment. If they had said that the lizards had sprouted wings and flew off the island, then they might have my attention. But this is ridiculous.

But wait, there’s more. The short-legged lizards are more likely to produce short-legged offspring. So, the future population will more likely be shorter-legged than the previous population (this would better fit the definition of descent with modification). The researchers said however, “Evolutionary biology is by its nature an historical science, but the combination of microevolutionary experimentation and macroevolutionary historical analysis can provide a rich understanding about the genesis of biological diversity [emphasis added]. In case you miss the irony let me point it out. The researchers believe this process leads to “biological diversity.” Did it not occur to them that the daughter population (containing only short-legged lizards) is less diverse than the parent population (containing long-legged and short-legged lizards)?

Let me leave you with one last quote; in response to the complaint that evolution has never been observed, Talkorigins.org says the following:

“Biologists define evolution as a change in the gene pool of a population over time [I thought it was descent with modification?]. One example is insects developing a resistance to pesticides over the period of a few years. Even most Creationists recognize that evolution at this level is a fact. What they don't appreciate is that this rate of evolution is all that is required to produce the diversity of all living things from a common ancestor” [emphasis added].

So, it is this kind of change (long and short legged lizards) that evolutionists claim is all that is required for common descent to occur. It’s equivocation of the worst sort. I’ve already pointed out that natural selection is when animals LOSE traits (like the lizard population losing the trait of long legs). Evolution requires animals to ACQUIRE traits (such as reptiles acquiring feathers to become birds). If you want to prove to me that evolution happens, I want to see animals acquiring traits. Stop showing me natural selection and calling it evolution.

No comments:

Post a Comment