"Ah! Now, that would be an entirely different matter. If it should be proved by some other means that Charlie did indeed evolve somewhere else, then we would be forced to accept that parallel evolution had occurred as an observed and unquestionable fact. Since this could not be explained within the framework of contemporary theory, our theories would be shown to be woefully inadequate. That would be the time to speculate on additional influences. Then, perhaps, your universal guiding force might find a rightful place. To entertain such concepts at this stage, however, would be to put the cart fairly and squarely before the horse. In so doing, we would be guilty of a breach of one of the most fundamental of scientific principles."

Somebody else tried to push the professor from a different angle.

"How about convergent lines rather than parallel lines? Maybe the selection principles work in such a way that different lines of development converge toward the same optimum end product. In other words, although they start out in different directions, they will both eventually hit on the same, best final design. Like . . ." He sought for an analogy. "Like sharks are fish and dolphins are mammals. They both came from different origins but ended up hitting on the same general shape."

Danchekker again shook his head firmly. "Forget the idea of perfection and best end products," he said. "You are unwittingly falling into this trap of assuming a grand design again. The human form is not nearly as perfect as you perhaps imagine. Nature does not produce best solutions—it will try any solution. The only test applied is that it be good enough to survive and reproduce itself. Far more species have proved unsuccessful and become extinct than have survived—far, far more. It is easy to contemplate a kind of preordained striving toward something perfect when this fundamental fact is overlooked—when looking back down the tree, as it were, with the benefit of hindsight from our particular successful branch and forgetting the countless other branches that got nowhere.

"No, forget this idea of perfection. The developments we see in the natural world are simply cases of something good enough to do the job. Usually, many conceivable alternatives would be as good, and some better.

"Take as an example the cusp pattern on the first lower molar tooth of man. It is made up of a group of five main cusps with a complex of intervening grooves and ridges that help to grind up food. There is no reason to suppose that this particular pattern is any more efficient than any one of many more that might be considered. This particular pattern, however, first occurred as a mutation somewhere along the ancestral line leading toward man and has been passed on ever since. The same pattern is also found on the teeth of the great apes, indicating that we both inherited it from some early common ancestor where it happened through pure chance.