A challenge to Darwin’s theory of sexual selection.

Sex: why is it so prevalent in nearly all species of life? Because its fun? Well maybe for some higher forms of life; however, plants and microbes practice sex also—we don’t see any smiles on them. The inefficiencies of sexual compared to asexual reproduction are enormous. Darwin and later Richard Dawkins the Darwinian champion failed to offer an evolutionary explanation. In fact, a recent theory rejects the notion that Darwin’s sexual selection theory offers a rationale for sex.

Evolution

Evolutionary proponents have struggled for over a century for a coherent explanation of why sex has become a reproductive strategy for the vast majority of species of life. Asexual reproduction is a more efficient means of passing on genes to the next generation. Many reptiles and fish perform some degree of asexual reproduction with females reproducing more females (males can’t do this).

The mathematics of a female producing a female, or one yielding two, is much more efficient than two yielding three. The list of inefficiencies goes on and includes the time and effort of finding a mate, the errors in the mixing of the two genomes, and many other arguments for vulnerabilities of the sexual motif.

Failing to justify evolution

The literature is riddled with publications attempting to show the evolutionary advantage of this seemingly inefficient process to pass on genes. One theory that cites parasites as the cause of sex is unconvincing. Another arguing that sexual populations have a more diverse gene pool and can adapt to a changing environment does not have strong scientific data to validate this assertion. Perhaps the search for a scientific rationale of how classical evolution explains sex is like someone looking for his keys under a lamppost because it only there that he can see. When people become mired in dogma, they vehemently attack alternative theories and see only under their lamppost.

A new truth emerging?

In 2006 an article appeared in the prestigious journal Science offering a new theory based upon group bonding and not on issues relating to reproduction. In fact, the theory argues that in sexual reproduction passing on “best genes” is not even involved in the behavior of the partners. This theory has both supporter and detractors. However, with enough supporters another lamppost illuminates new ideas and new experiments.

If this theory is correct, does it put nails into the coffin of evolution theory? No. It would, however, modify it. In my book, Healing the Rift, I devote a chapter to evolution and I believe that many of the principles are sound.

What are your thoughts?

Blog: Hypography.com life and the evolution of sex

Image source: royalty free Getty image.

This entry was posted on Friday, October 17th, 2008 at 3:18 pm and is filed under Explaining Life, Science & Spirituality. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.