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I sincerely apologize for my rudeness and foolish words, Physicist. And to everyone else as well. I read your post again and don't know why I lashed out the way I did. Although, I do have a tendency to attack when I see someone attempt to raise pseudo-sciences, like biology or psychology, to the level of real science, like physics. Physicist, your experience speaks for itself. I thank each of you for responding calmly to my inappropriate post.

Physicist wrote:
"And what makes YOU think that the force that keeps the moon in its orbit is the same thing as the force that keeps your keyster in its chair?"

The fact that placing an arbitrary mass next to another arbitrary mass results in a predictable perturbation. This is done in student labs everyday, where students are asked to measure the "gravitational constant" G by the use of a torsion balance.

Universal gravitation has overwhelming experimental evidence. It can be observed in the present at any time we wish. The same cannot be said of evolution. If for no other reason, its time scale is too large. Meaningful predictions cannot be verified.

I sincerely apologize for my rudeness and foolish words, Physicist.

Accepted.

The fact that placing an arbitrary mass next to another arbitrary mass results in a predictable perturbation. This is done in student labs everyday, where students are asked to measure the "gravitational constant" G by the use of a torsion balance.

Oh, you can measure gravity, sure. I'm willing to bet that you have not performed torsion-balance tests for the moon, however, or for the galaxy. Ultimately, you trust the practitioners in the field to perform different types of tests, and you trust them when they say that the theory is a good fit to the data. In this way, the universality of gravitation and the common descent of species (to compare apples to apples) are on the same intellectual footing from the layman's point of view.

Universal gravitation has overwhelming experimental evidence. It can be observed in the present at any time we wish.

But there's a fly in that ointment. Once you get beyond the scale of the solar system, a naive application of Newton's Law of Universal Gravitation breaks down. Stars on the rim of the galaxy orbit too quickly than can be accounted for by adding up the visible matter of the galaxy. (Google up the exact phrase "flat rotation curve" and you'll get a heap of information about this.) The standard explanation is that there's an undiscovered form of invisible matter permeating the galaxy, but until the precise nature of dark matter is elucidated, it falls in the category of an ad-hoc "fudge factor". (Amusingly, it's the creationists who howl the loudest about this.) If there is no dark matter--and we haven't found it yet--then gravity cannot have the same form everywhere and at all scales. In other words, gravity is not universal.

The same cannot be said of evolution. If for no other reason, its time scale is too large. Meaningful predictions cannot be verified.

I can level the same charge against universal gravitation, and in a supreme twist of irony, the relevant time scales are about the same. You see, in order to examine the behavior of gravity on a large scale, it is necessary to observe the light from distant stars and galaxies. Light has a finite speed, however, so when we observe the motion of stars around the galaxy, we are looking back 100,000 years, because they are up to 100,000 light years away. (Incidentally, 100,000 years is about as far back as you have to look in the fossil record to see evolutionarily meaningful changes in human fossils.) If you want to test the universality of gravitation on a still larger scale, by looking at the motions of galaxies in a cluster, you have to look back 100 million years. (In the fossil record, this takes you back to the time of the dinosaurs.) To test on a cosmologically meaningful scale takes you back to the time when life was beginning on Earth.

I myself have not performed these fossil-light tests of the universality of gravitation. (They have been performed by people whose word I take for it, however, with the dark-matter-contingent confirmation I mentioned before.) I have, however, personally performed tests of evolution upon the fossil record.

The slate beds of Pennsylvania provide a remarkably complete picture of a coastal ecosystem over a 34-million-year span of time. People have assembled long chains of fossils showing the morphological changes in several classes of animal. All it takes to falsify the picture of descent-with-modification is to find "later" forms in "earlier" beds. With my own hands I have dug fossil crinoids, trilobites and brachiopods, and verified that they occurred in exactly the beds where they should.