The answer is no, and it brings us to the 9th of Answers in Genesis' list of the ten myths of evolution: that natural selection is not evolution in action.
To put it simply, natural selection is only ONE of the driving forces behind evolution. There are also allele frequencies, genetic mutations, genetic drift, genetic variation, migration, descent, and coevolution, just to name a few.
Natural selection and evolution, though related, are not the same thing. Natural selection, as discussed before, is a mechanism of evolution. Evolution, on the other hand, is defined as the change in the allele frequency of a population over time (about 800 generations for most species). Natural selection is one of the mechanisms that governs the change in allele frequency. Heritable traits that help ensure the survival and reproduction of a population will be passed on, while those traits that don't help are killed with the organism. If people conflate the two ideas, and combine them into one, then they are simply being ignorant.
AiG doesn't like to associate anything with evolution (but, what did I expect), or Darwin for that matter. For example, they say that natural selection is an observable process that wasn't discovered by Darwin, and this somehow validates their argument.
Correct. Natural selection was not discovered by Charles Darwin, but rather proposed by him as a scientific theory in his book. Before Darwin, the idea that nature selects organisms for survival was simply philosophy, and had existed since antiquity. Darwin just connected descent with it.
AiG makes the point, later in the article, that "natural selection is nondirectional and does not lead anywhere. That is, if the environment changes, members of a species that were previously better adapted may no longer be. "
Once again, this is a correct statement. Nature is not sentient; it does not consciously determine who it wants to live or die. We often discuss nature as if it were actually doing so, but in reality it can't. The fact that natural selection is blind (much like Adam Smith's "invisible hand", referring to market economics) is one of the reasons why nature produces so many variations of species. It doesn't choose a specific species and allow only it to survive, it allows any organism that "meets the requirements" of survival in that environment to be favored. If an environment changes (an extremely long and drawn out process. At least, it was before humans), then the animals that have the traits which allow it to survive in that new environment will do so. This is not a conscious decision that is made by nature, it simply happens. Creationists don't like the idea of things just happening.
This is where the draw a distinction between natural selection and evolution: "Evolution, on the other hand, is an unobservable process that requires direction (dinosaurs to birds, e.g.)."
No, evolution (as defined above) is the result of random chance (mutations, etc) and non-random selection. It does not have a guide, only mechanisms that drive it forward. These mechanisms that drive evolution don't do so in any particular direction, therefore evolution as a whole does not have a direction. This is why it is such a slow process (it can take thousands of years for a speciation event to occur): because there is no goal, or no objective. Evolution did not start with the predisposition that dinosaurs changed to birds, that is just what was determined through study.
So, natural selection can only work on information that is already there, right? And when characteristics are selected for, doesn't that result in a loss of genetic information?
Yes and no. Once again, AiG is correct by saying that natural selection can only act on information that is already there. This is an obvious statement, because if there was nothing to select, then there would be no selection. But, to say that when characteristics are selected, the overall genetic information decreases, is just plain ignorant.
Let's take a population of, let's say, bears. For the sake of this argument, the bears have only 4 pieces of genetic information. Their DNA looks something like this, perhaps:
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These bears are living in an arctic environment, so they are completely covered in hair. Over time, the arctic environment begins to change to a more temparate environment, so the hair isn't needed. One of the 4 pieces of genetic information governs body hair:
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What would happen if a mutation occured, and that gene that governed body hair became modified, causing some bears to lose most of their hair.
Mutated bears (~1/8 of the population has this mutation):
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Regular bears the (rest of the population remains unchanged):
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In this case, the increase in temperature might cause the majority of the bear population to die out, leaving only the ones that mutated and lost hair (~1/8). That is what natural selection does, but notice: there was no loss of information, the information simply CHANGED. That is the biggest thing to remember about this. Unless the mutation specifically causes a deletion or duplication, there is no loss of genetic information. Now the bears who survived will reproduce, and eventually that population of bears will be completely different from the original ones. That is what we call evolution.
As a corollary to their previous point, AiG also claims that mutations have not been shown to reverse genetic information loss. In reality (which is the dimension that normal, intelligent people live in), some mutations can cause genetic information to increase via duplications. I won't go into the details as to how it happens, but you have to understand that genes can be duplicated during both mitosis and meiosis.
The final claim made by AiG regarding natural selection is that we, the "evolutionists", like to give powers to natural selection that it doesn't have.
To this I say: when did we ever do that?
"...we the "evolutionists", like to give powers to natural selection that it doesn't have."
ReplyDeleteLol much like they give powers to a MAN named jesus.