Two male penguins at Berlin Zoo have been caring for an abandoned egg since July in their long quest to become parents.
The same-sex couple, Skipper and Ping, are keen to have a chick of their own, and have even been known to "try to hatch fish and stones", spokesman Maximilian Jäger told the Berliner Zeitung newspaper.
He said the two king penguins adopted the egg, which had been abandoned by the sole female of the species at the zoo, and are "behaving like model parents, taking turns to keep the egg warm" by nestling it on their feet under a flap of belly skin.
The are now doing their best to protect their precious charge from jealous rivals, after a little encouragement from their human guardians.
'Knew what to do'
"We just had to put it on the feet of one of the guys, and he already knew what to do," says zookeeper Norbert Zahmel.
The female in the group of six king penguins has shown little interest in her eggs recently, and the zoo hasn't had a chick since 2002."A successful hatching would be great," Mr Zahmel told the BZ tabloid.
The 10-year-old pair moved to Berlin from Hamburg's Hagenbeck Zoo in April, and have been inseparable ever since.
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Gay penguins of either sex are nothing new, and are to be found both in the wild and in captivity.
But the heartache for Skipper and Ping may not be over yet. "The thing is, we don't know if the egg was fertilised," Maximilian Jäger says.
If they are lucky, Berlin Zoo will welcome its first chick born to a same-sex couple in early September.
Reporting by Martin Morgan
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