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A GenePoool.com Essay
Evolution
I don't think there's any question that, even though a lot of time has passed since the idea was first proposed, evolution is still one of the most hotly contested scientific theories of our time. And as much as the small voice in the back of my head screams at me that I should leave the subject alone, I think I would be remiss if I didn't throw my hat in the ring. I just hope that my head doesn't soon follow.
I'll begin by being blunt: evolution is an incontrovertible fact. Period. No mincing words here, not in this column.
Now, provided you survived that brazen assault, let me back up.
The word "evolution" is more commonly preceded by the words "the theory of," and for good reason. In the scientific vernacular, it IS a theory, but that does not mean that it is as tenuous and uncertain as most things we laymen would apply the word "theory" to.
This is how a non-scientist might use the word "theory."
"The detective had a theory: what if there WAS a one-armed man? But how could he prove it?"
If I were to turn the detective into a scientist, it might look like this.
"The scientist had a hypothesis: what if there WAS a one-armed man? But how could he prove it?"
Should the scientist prove the one-armed man hypothesis, he writes it up in a respected journal. Other scientists, seeking to test the hypothesis, either run the same experiments the first scientist ran, or design tests to determine whether predictions MADE by the one-armed man hypothesis are accurate. Usually, both types of tests are employed. Eventually, if enough experiments are done and enough questions are answered, the one-armed man hypothesis becomes a theory. By then, of course, the one-armed man has gotten away, which is why scientists would make lousy detectives, but that's not my point.
In scientific terms, a "theory" is as close as we come to a "fact." The very idea that something so nearly certain is referred to in such nebulous terms is a tribute to science itself. Self-correction is built into the language. And theories are often adjusted when a better explanation comes along. Newton's laws of motion and gravitation provide a spectacularly accurate method for predicting planetary motion, among other things; we would not have man-made satellites in space were it not for his work. But his theory broke down at extremely high rates of speed, as Einstein proved. The theory of relativity did not eliminate Newton's work, however.
Likewise, evolution has undergone a number of changes over time (no joke intended,) but no theory has come along that can better explain things without involving an aspect of evolution.
Creation "science" is certainly not an option. As a hypothesis, it's unsupported by the fossil records, and it makes no testable predictions. It's not even a "science." A 1987 Supreme Court ruling said as much, ruling that creationism is a religious idea, not a scientific one, and ergo, cannot be taught in schools.
The real purpose of creationism is not to provide evidence of a better theory, (as a genuine scientific theory would,) but to try to poke holes in the existing one.
One popular assertion is that evolution has not been proven because there are gaps in the fossil record. This is quite true; there ARE gaps. But this does not mean we should be throwing away the entire theory. Say, for example, I provide you with an ascending series of numbers:
1, 2, 3, 4, , 6, 7, , 9, 10.
I could claim that, based on the available evidence, I still have to find a 5 and an 8. You could rightfully claim that no, I'm actually missing 4.75 and 7.60. I'd ask you to back up this assertion, but it's at least in keeping with the basic premise. If, however, you claim that because I don't have two numbers I don't have an ascending series at all, that's simply going too far.
This is not the only "hole" creationism has found. One of my favorites involves a mis-application of the Second Law of Thermodynamics. It's a favorite because I love the idea of applying a scientific premise only where it comes in handy.
The essential "theory" of creationism is that the world was created all at once about 10,000 years ago. This number is arrived at by counting "begats" in the Bible. A few hundred years ago taking the Bible literally wasn't so difficult; today, however, a LOT of stuff has to be completely ignored to accept it as a completely literal history. Our skies are lit up at night by starlight that is more than ten thousand years old. The Grand Canyon took eons to carve, with water as the only tool in use. We've dug up a fossil record that goes back millions of years. There are desert cliff faces with fossilized remains of FISH in them. The Bible also holds that the earth if flat, and is the center of the universe. Is it possible that God put all the fossils where they are now, subverted the laws of physics, dug the Grand Canyon, and stuck fish bones in deserts, in order to fool us? I don't think I can accept such a capricious deity, but I'm sure there are some who can.
I suspect there are a large number of people who on the one hand find creationism a bit too extreme but who also have a good deal of trouble with evolution. This I can understand. One of the basic tenets of evolutionary theory is that on some level, every single living thing on this planet came from a single common ancestor (with the noted exception of microscopic organisms living in superheated steam vents in the earth.) This is not an easy concept to grasp, not when we look around us at the sheer breadth of life's diversity. How can EVERYthing we see have come from common stock?
One thing to take into consideration is the time span we're talking about is millions of years, not hundreds. Evolution is difficult to directly observe, because significant evolutionary change on a complex organism takes place over eons. But this does not mean evolution cannot be observed. Viruses and bacteria can mutate in a very short span of time. On a larger scale, we breed plants to gain a higher yield. Cows will die if they are not milked, because we've bred them that way. Domesticated animals are the direct result of the application of evolutionary basics.
But these are not the best examples, for while they prove that the mechanism for evolution exists, they are all the result of intelligent intervention in some way. Natural selection, an unguided evolutionary process, just isn't easy to cope with.
But that's just it; it's not really "unguided." Death is the final arbiter. There is nothing random, per se, about it. Simply put, if you were better equipped to survive, you survived. The dinosaurs were the dominant species on earth for a tremendous amount of time, but they were not equipped to survive extreme cold (which a cometary impact-- the currently popular theory regarding the dinosaur extinction-- would bring.) Our warm-blooded ancestors were.
We also have an aversion to the notion that we share a common ancestor with apes, and this, too, is understandable. (The shorthand term that we "evolved from the apes" is inaccurate. We didn't.) This aversion is very old, and may have started around the time the sexual tendencies of wild primates were taken note of. Really. Male chimpanzees have sexual intercourse on average every fifteen minutes for their entire adult lives. Other than eat, sleep, and hunt, it's pretty much ALL they do. In more prim and proper times the very idea that we have ANYthing in common with chimpanzees must have been appalling. And yet, difficult as it may be to accept, we share more than 99% of the same DNA.
It is simply not possible to study science without understanding evolution. It is THE central basis of modern biology. And yet there are still some states in this country where it is not allowed to be taught in schools. As the National Academy of Sciences put it, in a recent report:
"Biology simply cannot be taught well without covering evolution... Students who understand the process of evolutionary change are able to grasp its vital practical consequences, such as how bacteria develop resistance to antibiotics. A failure to teach effectively about evolution will rob students of a precious opportunity-- to understand how life on Earth has developed and to appreciate their own place in the world."
It may be an unpleasant prospect, but the fact
remains that the evidence in support of evolutionary theory is
simply overwhelming. To deny it is to throw away two hundred years
of medicine, biology, and archeology, just for starters. It may
very well be hotly debated in some circles, but not in any scientific
ones. And their standard of proof is a lot higher.
© 2000, Gene Doucette
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