Why have flamingos evolved to be pink?

They evolve to be pink because they evolved to become filter feeders that consumes brine shrimp and microalgae (and diatom). The things that they eat contains carotenoid pigment that dissolve in fats and are deposited in the growing feathers. read more

Actually, flamingos are not pink. They are born with grey feathers, which gradually turn pink in the wild because of a natural pink dye called canthaxanthin that they obtain from their diet of brine shrimp and blue-green algae. read more

Flamingos that eat mostly algae are more deeply colored than birds that eat the small animals that feed off of algae. So, you typically find deeply-colored pink and orange flamingos in the Caribbean, yet pale pink flamingos in drier habitats, like Lake Nakuru in Kenya. read more

Flamingos are large birds that are identifiable by their long necks, sticklike legs and pink or reddish feathers. Flamingos embody the saying "you are what you eat." The pink and reddish colors of a flamingo's feathers come from eating pigments found in algae and invertebrates. read more