Via Paul Hsieh (whose Geek Press I recommend reading daily, because it doesn’t take long–he only posts a few quality topics each day, and he always comes up with neat stuff), there’s an interesting article in the New Scientist about some recent developments in simulated evolution, in which artificial organisms develop capabilities based on mutations that would be seemingly unrelated to them.

Evidence of a gradual biological evolutionary process is found in complex structures that retain features related to earlier evolutionary steps. The human eye, for example, contains crystalline proteins that are related to those that perform enzymatic functions unrelated to vision.

The researchers say their computer model will let biologists study individual evolutionary steps for the first time. “Darwinian evolution affects DNA and computer code in much the same way,” says Christoph Adami, who leads the Digital Life Laboratory at the California Institute of Technology. “This allows us to study evolution in this electronic medium.”

Lenski adds that some mutations, which initially looked as if they would not be advantageous to an organism, turned out to be crucial stepping stones in the long run.

This is one response to the argument made by some that homosexuality can’t be genetic, because “the gene would die out.” This is reflective of an overly simplistic misunderstanding of genetic evolution. If homosexuality is purely genetic (and I won’t be surprised if it is) as opposed to womb environment or some combination of the two (it’s quite clear to me that homosexuals are born, not made), I’l be very surprised if it turns out to be a single gene. More likely it will be found to be a complex of genes, each of which has some non-sexual evolutionary utility, but in combination confer the unfortunate (at least in our present society) trait of inability to feel a physical attraction for the opposite sex.

A similar example is the gene for malaria resistance, very useful to people living in the tropics, but of which a double dose (from both parents) results in the deadly disease of sickle-cell anemia. In temperate climates, there’s no benefit to the gene at all, and it may eventually disappear in the African-American population, but it will take many generations.