WHY DOES SEX EXIST?

Friend Eric in Mérida passed along a link to a recent article in "The Economist" magazine, reviewing a paper dealing with the topic of why sex exists. Many organisms reproduce asexually some, most or maybe all the time, so is sex really necessary?

Two main hypotheses for why sex exists are talked about. The "Red Queen" hypothesis postulates that the constantly changing genetic variety provided by sex keeps parasites and pathogens from evolving stable techniques for attacking their ever-evolving host species. The second hypothesis, the "Plucking Rubies" one, suggests that sex's continual mixing of genes from generation to generation distributes good and bad mutations among a species' individual organisms, resulting in bad mutations disappearing when individuals bearing bad mutations die, while good mutations continue being passed along, refining the species.

So, sex exists because it helps a species evolve, not only to keep ahead of parasites and pathogens but also to refine the species.

Something interesting to notice is that when talking about why sex exists the reasons are formulated in terms of benefits for the species, not for us individual organisms in our individual lives. We organisms are at the service of the species concept.

Moreover, it's revealing that the whole species-making process, or evolution, depends on a certain percentage of certain kinds of us organisms not passing along our genes. Usually that means by dying before reaching reproductive age. In human terms, we're mainly talking about kids and young families, and traditionally the ones who have died have been those who inherited bad mutations, succumbed to parasites and pathogens, got involved in mindless violence, or belonged to societies that made themselves unsustainable through overpopulation, or by having religious or political beliefs, or a standard of living, so out of step with surrounding cultures that their neighbors exterminated them.

If sex exists to facilitate evolution, then evolution must be a very big thing. In fact, we've seen that not only does evolution organize and inspirit living things here on Earth, but also the whole Universe and all its contents evolve, as highlighted by the Six Miracles of Nature concept outlined at http://www.backyardnature.net/j/6/

When it finally sinks in that evolution is so important, that maybe it's even on par with the utterly mysterious and majestic fact that things exist in the first place, one begins wondering why humanity spends so little time seriously wondering "Evolving toward what?" and, "The species refining in what way?" and, "How should I be evolving right now?"

These mid dry-season days in the Yucatan when questioning Pheasant Cuckoos explode into my face and scarlet Bougainvilleas embroider deep, moist pools of shadow beside stone walls with big iguanas on them, a tourist visiting my humble hut asks what I do for a woman.

The entire above train of thought about evolution flashes through my mind, the woman, sex, peculiarities of our species, evolving "forward," "refining... " and I stand there with my circuitry so bumfuzzled that I fail to reply quickly, can't think of a witty reply, and don't feel like being witty anyway, in fact have quite forgotten what wittiness is all about. Just stand there until the tourist changes subject and points to a hole in the thatched roof, suggesting I'd best get it patched before late May, when the rainy season returns.