NORTH SEYMOUR ISLAND, Galápagos — The birds move with comic grace, like Fred Astaire and Judy Garland as hobo swells in oversize shoes. The male faces the female and slowly, slowly lifts up one foot, sets it down and lifts the other. Check out my feet! They’re blue. Really, really blue.

The female mirrors his ponderous moves. Mine are blue, too. Is this ground sticky, or what?

He leans over, spreads his wings wide, points his bill at the sky and whistles breathily, as if blowing on a toy flute. She grunts and totters up to him, and they clack bills. He grabs a pebble, and they clack bills again; he drops the pebble and spears a twig. Clack, whistle, grunt, whistle. And suddenly, she backs away.

Desperate, the male solemnly starts high-stepping again, displaying his beautiful teal-blue feet. But the courtship has fizzled, and when the female again lifts up a foot in response, it looks as if she’s waving goodbye.