A common mistake made by purveyors of evolution is to conflate natural selection, and evolution. The two ideas are not identical, nor is belief in natural selection tied to belief in evolution. In this article, I will discuss what each one is, identify their differences, and show why natural selection can stand apart from evolution.
In preparation for this article, I researched various definitions of evolution looking for one that was both honest and generally accepted. I searched through several dictionaries as well as numerous scientific periodicals and could not find one that was remotely universally accepted. Most definitions involve vague references to genetic changes and creation of new species, but are lacking in specifics. I have therefore put together a definition of evolution which puts together these discordant elements. Molecules to man evolution can be defined as follows: Changes within the DNA of an organism by purely natural means which, over the course of time, cause it to develop into a new kind of organism. This is Darwinian evolution in a nutshell. Darwin’s descent with modification into new kinds of organisms is the gold standard of evolutionary theory. The idea of evolution of not new to Darwin. It had bounced around under various names, including spontaneous generation, since the days of the Greek philosophers. Darwin was just the first to propose an apparently plausible mechanism for it. That mechanism was natural selection.
This brings us to natural selection. I was recently at a zoo and it claimed that Darwin originated the idea of natural selection. He did not. The idea had been kicked around in various forms since the ancient Greek philosophers. However, it was formalized in the mid-1800s by a creationist scientist named Edward Blyth. He built his ideas on the ideas of William Paley, a theologian and scientist. Neither used the term natural selection, but the ideas are incredibly similar to the idea Darwin popularized as natural selection. Natural selection can be defined as follows: “A process in nature in which organism possessing certain genotypic characteristics that make them better adjusted to an environment tend to survive, reproduce, increase in number or frequency, and therefore, are able to transmit and perpetuate their essential genotypic qualities to succeeding generations.” Essentially that means that organisms best adapted to their environment survive and pass their genes along to offspring. The base principle is that natural environments select for animals best suited for them, or animals live survive best in habitats they are suited for.
The two ideas are similar on the surface to one another. Both involve changes in organisms that make them more compatible with their environments. However this is where the similarity ends. Natural selection works from pre-existing genetic information. Darwinian evolution requires the formation of new genetic information, or at bare minimum a sizable reshuffle of existing information. Natural selection does not require any adjustment to existing information. Instead, it merely picks out the information best suited to a given environment. Environmental factors such as weather, predators and food sources increase the likelihood of a negative trait, such as lack of camouflage, being weeded out of the population. However, this represents an information loss, not gain. Natural selection is actually the opposite of Darwinian evolution.
Despite the differences, Darwinian evolution requires natural selection in order to be a viable theory. Evolution requires a mechanism of change. Mutations can only be used to explain changes, they cannot explain why certain changes are passed on and others are not. This is where natural selection comes in. Evolutionists claim that natural selection ensures the elimination of unfit organisms and the survival of fit organisms. This is largely correct. However, by so doing, it removes information from the gene pool. If this information was all negative information, this would be a good thing. However, much of it is situational. For example, a feline species with white fur would not do well in a tropical rain forest and thus would be selected against in that environment. However, a feline species with bright yellow and black fur would fit in poorly in an arctic community and be equally selected against. Neither is a definitively negative trait, but becomes negative when placed in the wrong situation. However, the fur color would disappear from the genome after several generations of being selected against. This is a loss of viable genetic information. This is the opposite of evolution. Evolution requires a gain of information. Natural Selection requires a loss of information. Natural selection happens. Animals unfit for their environment, such as albino tigers, rarely survive in the wild. However, since this is opposite evolution, natural selection does not require evolution to work. Viewed as variation within a set kind, natural selection works brilliantly as an explanation for the variation we see in the various kinds through out the world.
Evolution needs natural selection, yet natural selection actually argues against the Darwinian theory. Natural selection does not need evolution. It can stand on its own as an explanation for the variation seen within species of the same kind in different parts of the globe. Evolution is married to natural selection, but natural selection is easily divorced from evolution.