London, Oct 21 (ANI): A new study has revealed that king penguins do not form long-term homosexual pairs despite same-sex "flirting".
Researchers found that over a quarter of the birds in one colony displayed in same-sex pairs, yet only two pairs bonded by learning each other's calls and both were later seen caring for eggs in heterosexual pairs.
The scientists suggest that an excess of males or high levels of testosterone could cause these same sex displays.
Researchers from the Centre for Functional and Evolutionary Ecology in Montpellier, France studied king penguins on the Antarctic island of Kerguelen to better understand there mating behaviour.
During the mating season king penguins displayed with potential partners: closing their eyes, stretching their heads skyward and moving them in a half-circle to "take peeks" at one another.
The scientists did not set out to measure rates of homosexuality in king penguins. Instead, they came to their conclusions after studying the birds' behaviour and crucially, sexing individuals.
In doing so, they ended up with the first evidence-based study of homosexuality among king penguins, and one of the first among all penguins.
In their study the researchers found that 28.3 pc of the birds studied displayed to penguins of the same sex.
"Of course, it took DNA sexing to work this out since males and females look so similar," BBC News quoted Director of Research, Professor F Stephen Dobson, as saying.
In the past, it was claimed that penguins could not discern between the sexes because they looked alike.
However, Professor Dobson debunked this theory when his results did not meet "random" projections.
"I found that the rate of homosexually displaying pairs was significantly lower than one would expect by chance."
Of the displaying pairs, he observed, only two bonded, "Among 75 bonded pairs, we found one male-male pair and one female-female pair that had learned the song of their partner."
"So these [homosexual] pairs can bond. But, bonded pairs can split up if one finds a more preferred partner," Dobson added.
The study has been published in the journal Ethology (ANI)