Saturday, June 7, 2008

Senses of "evolution"

The word "evolution" is used in so many senses that it's often confusing. The most commonly used senses I've heard are:

* Development of an individual ("I started out as a mathematician. But I gradually evolved into an engineer").

* Development of an idea ("Continue the discussion, and brainstorm, until your ideas evolve into something you can put into use.")

* Development of a design ("Cars evolved from the relatively primitive Model T to the modern Hybrid.")

* Adaption of an organism ("Organisms vary naturally, and those best suited to their environment tend to spread.")

* The story of the origin and history of life ("Life appeared as a spontaneous, self-replicating protocell, and developed through variation and natural selection into everything we have around us today.")

What's interesting to me is how loosely many evolutionists use the terms. I once made the old argument that "similarity does not imply common descent any more than it implies common design because there are "intermediate forms" among cars, but we all know cars didn't evolve" to an evolutionist. His response was puzzling -- "Of course cars evolved, you idiot -- look at the changes in them over time!"

I found this to be amazing. The fundamental difference between change in gene frequencies stemming from unguided, natural processes and the "evolution" of cars through the intelligent effort of hundreds of thousands of engineers over the course of a century" seemed to be totally lost on him.

Similarly, I remember watching a youtube video by other evolutionists in which the narrator said, "If it can grow, it can evolve." The fundamental difference between an individual changing due to inborn programming and change in gene frequencies stemming from unguided, natural processes appeared to be lost on her, too.

Then today, I ran across this blog by a PhD, in which he rather extraordinarily says:
"But we most certainly do not need fossils to demonstrate the fact of evolution, as we are surrounded by evolutionary intermediates right here in the modern world. In fact, if we didn't have any fossils at all we would still conclude - from the living organisms that surround us - that evolution happens..."

In what sense is he using the word "evolution" here? Does he mean changes in gene frequencies due to unguided natural processes? If so, then how does he know that organisms are intermediates without a fossil record to show a path of development from a common ancestor to the divergent species? How can one conclude that organisms are "evolutionary intermediates" without identifying their common ancestor which would necessarily only be found in the fossil record?

These "scientists" never seem able to grasp that point. They don't seem willing or able to effectively define their terms in this area such that criteria can be effectively applied to test whether reality corresponds with theory.

The real question about "evolution" is not whether organisms adapt to their environment through variation and natural selection. That's obvious, and was known well before Darwin ever showed up on the scene. The real question is also not whether many organisms have similar characteristics. That's also obvious, and was known long before Darwin ever showed up on the scene.

The real question about evolution is unguided, universal common descent. The idea that everything descended from a single protocell that came about by happenstance and subsequently diverged into all life through variation and natural selection alone. That's the only point of contention.

Does this guy seriously think you can make claims about history without looking at the historical evidence of fossils?

If he does, he's an idiot.

But I don't think he does. He probably never sat down to really think through what he means by "evolution."

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