|Bugs Aren't Gay, Just Confused|
Scientists studying homosexual behavior in insects - courting, mounting, and trying to mate with members of the same sex - have concluded that homosexuality in insects and spiders is just a case of mistaken identity.
Many species of insects and spiders engage in homosexual behavior, but scientists are unclear how it benefits the survival of the species. Like heterosexual behavior, engaging in sex with members of the same sex takes time and energy and can be dangerous — and it lacks the potential payoff of procreation.
In birds and mammals, homosexual behavior has been shown to provide "practice" for young adults and maintains alliances within groups. Scientists have suggested that similar behavior in insects could prepare them for heterosexual courtship, dispose of old sperm, discourage predators, or distract competitors. But in reviewing research on some 110 species of male insects and spiders, the researchers at Tel Aviv University' found that the available evidence weakly supports such adaptive theories.
In general there is no clear benefit to homosexual behavior in insects. The costs, on the other hand, can be considerable. Homosexual mating is at least as risky as the heterosexual kind, expending sperm, wasting time that could go toward other activities, and boosting the risk of injury, disease, and predation.
In a previous study, the researchers found that all of these factors shorten the lives of heterosexually active males by an average of 25 percent. They expect homosexual behavior to be similarly costly.
The researchers say insects and spiders probably have not evolved to be more discriminating in their mating choices because the cost of rejecting an opportunity to mate with a female is greater than that of mistakenly mating with a male. This explanation is supported by the fact that many species that exhibit homosexual behavior also mate with related species or inanimate objects, like beer bottles — indicating a general tendency toward misidentification. It is also possible that sexual enthusiasm in bugs is related to other evolutionarily beneficial traits, the researchers say.
"Homosexual behavior may be genomically linked to being more active, a better forager, or a better competitor," says Dr. Schart. "So even though misidentifying mates isn't a desirable trait, it's part of a package of traits that leaves the insect better adapted overall."
sources: Tel Aviv University
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The Search for Life That Is Very, Very Different from Our Own
As a consequence of space exploration and the realization that life on other planets might be very different from what we are used to, scientists in recent decades have improbably discovered bizarre life forms here at home in places previously deemed uninhabitable.
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