Flamingo make-up. Greater flamingos use pink preen oil to cosmetically enhance their plumage colour.

Greater flamingos (Phoenicopterus roseus) are one of the few non-human species to use make-up. The oil that they preen into their feathers for waterproofing is saturated with carotenoid pigments (that makes them pink). By preening more when getting ready for breeding, they make their heads and necks a brighter pink, as can be seen by some of the birds in this flock.