The same-sex penguin couple Rocky and Marama made headlines this year after adopting a chick at the Sea Life London Aquarium, and now the longtime duo is making history — by parenting what may be the world’s first “genderless” penguin chick.

The 4-month-old chick, who has yet to be named, “will be the first of its kind in the history of the famous London aquarium not to be characterized as male or female,” according to Sea Life.

Sea Life London Aquarium's Charlotte Barcas helps place a purple identification tag on the aquarium's first Gentoo penguin to not have its gender assigned. Jonathan Short

“While the decision may ruffle a few feathers, gender neutrality in humans has only recently become a widespread topic of conversation,” Graham McGrath, the aquarium’s general manager, said in a statement. “However, it is completely natural for penguins to develop genderless identities as they grow into mature adults.”

Despite this, however, newborn penguins are routinely given gendered names and colored tags at Sea Life — until now, that is. The adopted chick of Rocky and Marama has been tagged with a “gender-neutral” purple band for identification purposes.

As for why this particular chick was chosen to be the aquarium’s first “genderless” one, Sea Life noted that this chick “captured the Aquarist team and guest’s imaginations after it was successfully adopted by two female penguins.”

“This was the first time we had successfully adopted a chick onto a same-sex couple and to mark the parenting achievements of Rocky and Marama in helping to develop the chick into a happy and healthy penguin,” Sea Life wrote in a statement. “It made sense to continue to allow it to be identified more naturally by staff and guests at the aquarium in the future.”

Rocky and Marama are not the only same-sex penguin parents to make international news. Another Gentoo duo, Magic and Sphen, adopted a chick last October following a successful trial run with a dummy egg at the Sydney Sea Life Aquarium. And the month before, two male penguins at a Denmark zoo nabbed a chick while its mother was swimming. The zoo staff returned the little one to its biological parents soon after, but took heed of the couple’s nurturing affect and found an egg in need for them to raise.

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