Researchers found new evidence of the importance of make-up while studying Spanish flamenco dancers flamingos. The scientists discovered that the birds augment their signature coloring by applying tints drawn from their own glands–and they use their painted plumage to attract mates.
The hue of the leggy birds’ feathers come primarily from the pigments in their diet, but researcher Juan Amat found that they also secrete the colored pigments, called carotenoids, from their preen glands. Flamingos (and many other birds) press their heads to the preen glands at the base of their tails to pick up feather-protecting oils, which they then spread around their bodies.
The researchers realized that those oils contain pigments, ranging from red to yellow, by keeping an eye on the flamingos’ feathers and behavior: They noticed that the coloring of the birds was brightest during the mating season, and quickly diminished after they found a mate. Amat told BBC News:
“The rubbing is time-consuming,” Dr Amat told BBC News. “And the more frequently the birds practise it, the more coloured they appear. If the birds stop the rubbing, [their] plumage colour fades in a few days because carotenoids[pigments] bleach quickly in the sunlight.”