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Why Sexual Fluidity May Be the Norm
How a recent theory about evolution may overturn millennia of assumptions
Homosexuality has been called The Great Evolutionary Puzzle. Ever since Darwin, those who think deeply about such matters have been trying to understand why humans exhibit homosexual (same-gender attraction) behaviors.
As organisms are essentially bags of genes and as the genes that do the best job of ensuring they get passed forward into future generations are the ones we end up with, and as mating is the way in which animals accomplish this passing forward, same-sex mating appears on the surface to be counter-intuitive. Because obviously same-sex mating for most animals (flies and a very small number of other creatures being the exception) doesn’t result in genes being passed forward.
So why does homosexual behavior persist?
A couple of decades ago a team of researchers hypothesized that if a gene conferred significant reproductive advantage to one gender such that it outweighed the reproductive cost in the other gender, this could explain the persistence of homosexual behavior. Candidate genes were duly identified in humans.
Unfortunately for this theory, homosexual behavior is seen in such a wide range of animals involving such a wide diversity of genes that it seems implausible such benefit-cost models…
