Saturday, 22 November 2008

Is There a "Symetry Gene?"

OK, so this might seem silly, but sometimes the silliest seeming questions are the ones left unanswered.

We have a new kitten. It is a tabby with brown, black and tan markings. The pattern of the markings are the same on both her sides, and I found myself wondering why. The simplest answer is that she got her pattern from her parents, but that is not very satisfying. One can just keep asking, "Where did they get it from?" all the way back to the beginning, whenever that was.

The same question could be asked about humans. Why do we have five fingers on both our right and left hands? Why five toes on each foot. Why, in effect, are the right and left sides of our bodies mirror images? How do genes work. Is there a, 'mirror-image gene' that ensures both halves of our bodies are the same? Or are we the way we are because our parents and hence our ancestors were that way?

Which leads me to the evolutionary part of this question. If we trace ourselves, and all life, back to some kind of blob, what was it that caused both sides of our bodies to be the same? Wouldn't that be the world's greatest coincidence? And if we, and all plant and animal life, came to be the way we are through a countless series of mutations, why are virtually all animals built the same way today? Wouldn't some of these mutations have affected this particular attribute? They certainly seem to have affected a multitude of others.

Now the evolutionists say that the creatures that survive have done so because they were more suitably adapted to their environments that those that didn't. In other words, if a certain mutation gave its recipients a survival advantage, then those specimines would eventually take over and the disadvantaged ones die out. But is there any record, fossil or otherwise, of any extinct animal sepcies that are unsymetrical? Besides, it wouldn't seem to me to be a particular disadvantage to have had five fingers on one hand and seven or eight on the other? Why aren't there more people or animals around with these or other "abnormalities?"

One of the advantages, for instance, that we humans have, along with the great apes, is the "opposing thumb." Why are both thumbs opposing? There are evolution sites that explain its development but no one thinks to wonder, let alone explain, what mutation happened to develope it on both hands at once? Or are there fossil records of our ancient ancestors with only one of them?

As I said, these may seem like silly questions. But sometimes the experts are so concerned with the complex questions that they don't see or bother with the simple ones. Far be it for me to expect that anyone with expertise in genetics might read this blog, but I would like to hear an explanation. If there is a gene that automatically ensures our bodies are, 'mirror imaged,' that is one thing. But if our bodies are the way they are just because every one of our ancestors were, I'm afraid that leaves a lot of unanswered questions.

Or maybe we were just made that way? Go figure.

Take Care

No comments: