At the Central Park Zoo, two male chinstrap penguins named Roy and Silo formed a devoted bond in the late 1990s. Keepers noticed them bowing to each other, entwining their necks, and building a nest together. In 1999 they were even seen trying to hatch a rock, treating it with the same care as an egg. Recognizing the strength of their partnership, zookeepers gave them a fertilized egg that another pair could not raise. Roy and Silo incubated it together and successfully raised a chick named Tango.

This challenges the idea that animal relationships must fit into strict categories. While they were a same sex pair, Silo later formed a bond with a female penguin named Scrappy after he and Roy drifted apart. Rather than framing their behavior as fixed or limited, it can be understood as fluid. Their bonds appeared to form around connection and attachment rather than rigid sex distinctions. In that sense, their story has often been embraced as an example of pansexual possibility in the animal world, where affection and partnership can cross expected boundaries.

Stickers are about 10cm big