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The Facts Of Evolution

Kevin Baldeosingh •16 April 1999 • 861 words

"The second most frequent statement of those who disbelieve in evolution is that it is "just a theory". But that assertion rests on a confusion between popular use of the term "theory" and its scientific application. In common usage, "theory" is synonymous with "logical assumption" or "hypothesis".

Although I did Biology up to Form Five at Presentation College, San Fernando, I was never taught about the theory of evolution. In fact, though I was aware of Darwinism from my own reading, I never even heard about evolution in school until Form Six, when I sat in on the Religious Knowledge class for Catholics where the principal, abandoning his function as educator in order to fulfil his role as priest, fed the boys a list of wrong ideas about evolution.

Religious propagandists devote considerable energy towards trying to show that the theory of evolution is wrong. There are two main reasons for this. The first, and minor, one is that evolution theory is less technical than cosmology or quantum mechanics and so seems easier to refute. The second, and major, reason is that evolution, without resorting to a Creator, provides an explanation for life itself. Theoretical physics does the same, but not in ways the layman can easily understand. And, besides, cosmology and quantum physics have fewer facts to support them than evolution. But you'd never know this from listening to the religious demagogues.

All of them use the same lines of attack. Their primary argument is that all the design we see in Nature proves there must have been a Designer. In fact, it proves no such thing. Design is an inevitable consequence of evolution because function is impossible without design. Moreover, if there was a Divine Designer, questions arise as to why He didn't do a better job - why is there a blind spot in our eyes, why is birth so difficult for humans but not other mammals, why do some organisms show signs of devolution?

The second most frequent statement of those who disbelieve in evolution is that it is "just a theory". But that assertion rests on a confusion between popular use of the term "theory" and its scientific application. In common usage, "theory" is synonymous with "logical assumption" or "hypothesis". But, in science, a theory is a hypothesis which has been proven by evidence and experiment beyond reasonable doubt. The reason scientists calls theories theories is simply because science never claims to offer certainties. (This is why scientists do not settle their disputes by killing one another.)

Another common refutation of evolution offered by religions' spokespersons is that, although the theory is founded on the assumption that species change over time, there are no intermediate forms in the fossil record. But this is simply not true. Paleontologists have found many transitional fossils which represent the evolution of one major form of life into another. There are, for example, skeletons of extinct animals showing the transitions from primitive fish to bony fish, from fish to amphibian, from amphibian to reptile, from reptile to mammal from reptile to bird and even from land animal to whale (there are fossil whales with four legs, and modern whales still have remnants of hind legs buried in their flesh). Recent advances in DNA mapping provide further evidence of species evolution.

There is now abundant fossil and DNA evidence showing transitional diversifications among mammals into rodents, bats, rabbits, carnivores, horses, elephants, manatee, deer, cows and many others. And one of the most finely divided sequences of transitions documents the evolution of apelike creatures through half a dozen intermediate forms into modern humans.

As regards this last, I believe the missing link - the hominid which directly preceded homo sapiens - is still missing, but that is only because most kinds of fossils are extremely rare. After all, to become a fossil an organism must die in places where conditions are both right for preservation (such as sediments with preservative properties) and which will undergo erosion or uplifting that exposes the long-buried remains millions of years later. The wonder, therefore, is not that the fossil record has gaps but that we have such a good record at all.

A more sophisticated argument offered against evolution is that the mutations necessary for it to occur are highly improbable. This criticism was first voiced, I believe, by Sir Fred Hoyle, who was a physicist and thus no doubt felt himself qualified to pronounce on matters of biology. Certainly, evolution is so improbable as to be impossible if you posit major and sudden changes. But evolution does not claim this: instead, it posits very small changes over very long periods of time. Computer simulations based on natural selection, and random mutations based on statistical data worked out by biologist Sir Ronald Fisher and population geneticist Motoo Kimura, show that species evolution is not only possible, but probable.

None of these facts, of course, would persuade the truly faithful. For Hindus, the geneticists are wrong since the Vedas say Hinduism is billions of years old. For Muslims, the biologists are wrong since the Qu'ran says Allah created every living thing. But I especially like the argument of fundamentalist Christians, who argue that God put fossils in the earth in order to test their faith. I don't believe in God but, if He exists, the concept of Him as a Cosmic Prankster is one I find quite attractive.