The flamingo's bright pink coloration comes from its diet—animals can't synthesize the carotenoids that color these feathers. The more carotenoid-containing food a flamingo eats before molting and growing new feathers, the brighter those feathers will be. Over time, though, the color fades. So how does a flamingo attract a mate months later, during breeding season? Through the clever use of cosmetics, says a new study in Behavioral Ecology and Sociobiology.
Scientists studying greater flamingoes (Phoenicopterus roseus) in Spain found that the birds secrete carotenoid pigments through their uropygial glands near the tail. When breeding season nears, a bird will rub its cheeks on the glands and then spread the secretions over its neck, breast and back feathers, enhancing the pink pigmentation. The more frequently they do this, the pinker they become and the longer they stay that way—the color fades within days without reapplication.
The pink color is a signal to other birds of a flamingo's fitness, and brighter birds have more successful love lives, the scientists say. The birds start breeding earlier, which lets them claim the better nesting sites and increases breeding success.
Once a flamingo has found a mate, though, the bird stops applying its make-up, which takes a lot of time and energy. I suppose it's the flamingo equivalent of letting yourself go.