Yet things began to fall apart in May 2004 after the two were kicked out of their nest by two aggressive penguins. They drifted apart, Mr. Gramzay said, and early in the mating season this year Silo found Scrappy, an import from SeaWorld who had been lounging around the aquarium since 2002.

Still, Mr. Gramzay said that humans should not divine too much from the split. "People read so much into the gay thing, and the gay thing is necessarily a human constraint that's put on top of them."

That has not stopped many from doing just that.

At the Web site for Focus on the Family, an influential organization run by radio host James C. Dobson, who has called homosexuality a disorder and advocates converting gays, a commentator, Warren Throckmorten, wrote: "For those who have pointed to Roy and Silo as models for us all, these developments must be disappointing. Some gay activists might actually be angry."

Well, maybe not angry. As Roberta Sklar, a spokeswoman for the National Gay and Lesbian Task Force, put it: "There's almost an obsession with questions such as, 'Is sexual orientation a birthright or a choice?' And looking at the behavior of two penguins in captivity is not a way to answer that question."

She said the furor over the penguins "is a little ridiculous. Or maybe a lot ridiculous."

Perhaps it is because penguins of all stripes have become hot political commodities of late. The surprise hit of the summer was "March of the Penguins," in part because it was embraced by Christians and conservatives, who see in the film pro-family and Christian imagery.