After fruitless attempts to hatch stones and fish, a gay penguin couple at a German zoo may finally be able to parent a chick of their own.
Zoo Berlin officials announced that two of its male king penguins, Skipper and Ping, have eagerly adopted an egg. It'll be the pair's first chick, if all goes well.
The couple arrived together from a zoo in Hamburg in April, and their bond was evident as soon as they arrived, zoo spokesman Maximilian Jäger said.
In July, keepers decided to give Skipper and Ping a real crack at parenthood. One of the zoo's female king penguins laid an egg, but because she had never hatched her previous eggs, staff members decided to donate it to the pair, he said.
The couple, who had taken turns nursing rocks and bits of food between their feet and trying to hatch them, were more than willing to oblige.
Staffers aren't sure whether the egg is fertilized, and incubation typically takes about 55 days, according to the Cornell Lab of Ornithology. But if the egg is viable, it'll be the first penguin at the zoo born to two fathers, Jäger said.
Though staff members are thrilled for the prospective parents, Jäger said they're celebrating the news by "giving them as much calm as possible," essential for a successful hatch.
Other notable gay penguin pairs
Jäger said the zoo's seen plenty of same-sex penguin couples, and now, Skipper and Ping might join a storied lineup of gay penguin parents.
In June, the ZSL London Zoo celebrated longtime lovers Ronnie and Reggie with a banner that read, "Some penguins are gay. Get over it." The two Humboldt penguins hatched an abandoned egg in 2015.
Keepers at Sydney's Sea Life Aquarium in Australia welcomed a baby gentoo penguin, Sphengic, lovingly named for her adoptive dads, Sphen and Magic.
Perhaps most famous, male chinstrap penguins Silo and Roy found love at the Central Park Zoo in 1998 and hatched and raised a chick named Tango. Their family inspired an award-winning children's book.
Their love soured in 2005 when Silo left Roy for a female named Scrappy. Roy ended his tenure at the zoo alone before transferring to another facility.
Hundreds of animals partner up with members of their sex
Gay coupling certainly isn't limited to penguins. They're one of at least 450 species observed to partner up with another member of their sex, according to a 2009 review of same-sex animal behaviors.
Bonobos, apes closely related to humans, have been extensively recorded engaging in sexual activity with males and females, with female-female pairings particularly popular. Studies of bottlenose dolphins have found that half of males' sexual encounters were with other males. And more than 30% of female albatross in a Hawaiian colony bonded for life, sharing chick-rearing duties, researchers wrote.
Animal behaviorists are split on exactly why animals couple up with members of their sex when there's no reproductive potential.
Sure, some animals might not be able to discern a male from a female, but often, animals pair up because they're seeking a strong bond and a co-parent, researchers said in the review.
Like humans, many species engage in "non-reproductive sexual behavior." And if there are more females than males in a group, same-sex partnerships are more than likely, according to the study.
For penguins, monogamy of any sort is convenient and necessary: One partner can hatch the chick while the other forages for food. Plus, huddling with a loved one can make the Antarctic cold a bit more bearable.
So here's to Skipper and Ping; may the two embrace parenthood as openly as they've embraced each other.