In 2004, two male chinstrap penguins in New York's Central Park Zoo named Roy and Silo started performing mating rituals with each other and began attempting to hatch a rock as though it were an egg. Zoo officials subsequently gave them an actual egg from another pair of penguins who were unable to hatch it. Roy and Silo hatched the egg and the couple raised a chick named Tango.
"And Tango Makes Three," a children's book about the nontraditional spheniscid family penned by Justin Richardson and Peter Parnell, a noted playwright, was promptly ordered removed from school libraries in Meckleberg County, North Carolina. The book topped the American Library Association's list of most frequently challenged books in 2007, 2008, 2009, and 2011.
