From the Telegraph.
The pairing of same sex couples had previously been observed in more than 1,000 species including penguins, dolphins and primates.
However, in the latest study the authors claim the phenomenon is not only widespread but part of a necessary biological adaptation for the survival of the species.
They found that on the Hawaiian island of Oahu, almost a third of the Laysan albatross population is raised by pairs of two females because of the shortage of males. Through these 'lesbian' unions, Laysan albatross are flourishing. Their existence had been dwindling before the adaptation was noticed.
Other species form same-sex bonds for other reasons, they found. Dolphins have been known engage in same-sex interactions to facilitate group bonding while male-male pairings in locusts killed off the weaker males.
....
Dr Bailey said: "It's clear same-sex sexual behaviour extends far beyond the well-known examples that dominate both the scientific and popular literature – for example, bonobos, dolphins, penguins and fruit flies.
"Same-sex behaviours – courtship, mounting or parenting – are traits that may have been shaped by natural selection, a basic mechanism of evolution that occurs over successive generations," he said.
"But our review of studies also suggests that these same-sex behaviours might act as selective forces in and of themselves."
Had I known about the fruity fruit flies yesterday during my visit to the Audubon Insectarium, I'd have inquired as to whether they had specimens.
Of course, this information will mean nothing to those folks who do not believe in natural selection.
Yeah, yeah, I know, The Telegraph is not the most trustworthy source, but if you doubt, read more from Wired Science in their article titled, "Is Homosexuality an Evolutionary Step Towards the Superorganism?"
Only by conceiving of evolution as acting upon entire populations rather than individual organisms can we understand eusociality — the mysterious, seemingly "altruistic" behaviors exhibited by insects who forego reproduction in order to care for a colony’s young.
So says Edward O. Wilson, the legendary sociobiologist, environmentalist and entomologist, in an article published in the January issue of Bioscience. Wilson doesn’t extrapolate from bugs to people, but his conclusions raise fascinating questions about the evolutionary aspects of non-reproducing humans.
....
So with all necessary caveats against reductionism and misappropriation, we can ask: should human societies conceive of themselves in terms of group-level selection? Have we already developed aspects of eusociality? And — just to make matters really interesting — could non-reproducing humans, such as (most) gays and lesbians, as well as heterosexuals who choose not to have kids, actually be a manifestation of this emergent eusociality?
Citing eusociality in defense of any lifestyle choice, even theoretically, could backfire: it implies a subservience of individual well-being to the greater good. But at least it suggests that certain unorthodox lifestyles might not be so "unnatural" after all.
Image from Wiki.
Update from the comments by IT:
However, I must tell you that the photo you have chosen of Acidia cognata is not what we commonly think of as a "fruit fly" in genetics research. Rather, the workhorse is Drosophila melanogaster, and most "fruit flies" you see around the house are, if not melanogaster, some sort of related Drosophila species.
And here is Drosophila also from Wiki.




