What Is Evolution and Natural Selection?

I don't know if it's by design or circumstance, but (apart from the religious and ideological elements) part of the resistance to evolution has to do with the fact that a number of related but distinct concepts are normally conflated with each other, so that if you disagree with one, you automatically assume that you must disagree with all of them. For instance, many people confuse natural selection with evolution, and think of them as interchangeable concepts, but the former is simply the most famous, and possibly main mechanism driving the fact of the latter.

And talking about facts, people also tend to confuse the fact of evolution with the theory of evolution. Evolution, the change in (gene) allele frequency in populations over the span of multiple generations, is a fact that even the most hard-core creationists can't deny with a straight face (after all, you are not identical to either of your parents, nor to your own children). The theory of evolution is a scientific model (and by far the most successful account so far) to explain, understand and make sense of the fact of evolution (why it happens). And to bring it all full-circle, the theory makes use of various mechanisms, most notably, though not exclusively, natural selection. So yeah, I can understand why some people might get a little confused...

But if that seems needlessly abstract, here's a little animation to clarify what evolution is:

Having established that, the next point to touch on is the consequences of evolution and what it implies about us and our place in the grand scheme of things. Many people tend to disagree with evolution, not because it's not supported by more evidence than we know what to do with or because it doesn't make sense but because, as a kind of universal acid, it tends to undermine our inflated egos.

We like to think of ourselves as fallen angels, ignited by a kind of divine spark, but it may be more accurate to say that we are risen apes, and that we can trace our inglorious genealogical lineage all the way back to pond scum. Then again, how is that any worse than thinking we come from dust?

But before we consider the logical implications of this idea, here's a little lesson, again clearly articulated, explaining the basic logic behind the mechanism of natural selection:

And here's why the idea of 'intelligent design' is undermined by our observation of fossils and the massive number of extinct species: evolution is a 'blind watchmaker,' a tinkerer (not a designer) whose success is acquired by the death and destruction of all those experiments that ended up failing.