Flamingos have existed in some form since at least 30 million years ago, and over this period, they have adapted in a number of unique ways to their habitat. They live in deep, salty, coastal lagoons, a harsh environment that few other birds or animals inhabit. Predators have a tough time reaching flamingos in their natural habitat, and these birds do not compete with very many other animals for food and resources, since they can tolerate conditions that other creatures cannot. As flamingos adapted, they also spread, expanding their habitat into new areas that were unpopulated by other creatures. In order to survive in these conditions, the birds have evolved to develop long necks, long legs, unique beaks, and unusual methods of feeding.
Necks, Legs and Feet
Long legs are a common trait for wading birds, as are long necks, but flamingos have the longest legs and necks, relative to body size, of any bird. This enables them to stand in relatively deep water, where they can stir up mud at the bottom to obtain food. They are also able to reach deep into the water with their long necks to feed.
The birds have broad, webbed feet, which allow them to stay stable on soft or uneven surfaces like mud. When flamingos go into water that is too deep to stand in, they float on the surface, using their powerful webbed feet to keep themselves up and steer towards likely sources of food.
Beak and Feeding
One unique way in which flamingos adapted is in the structure of the beak and mouth. The birds submerge their heads upside down in the water to feed, and the jaw is built in reverse to accommodate this — unlike any other bird or mammals, the lower jaw is fixed and the upper part moves. The internal structure of the mouthparts has evolved for feeding in muddy water. The inside edges of the beak are lined with rows of small bristles called lamellae that allow them to filter the water by forcing mud, silt, and impurities out using their muscular tongues. This leaves nutritious food, which consists of mollusks, worms, crustaceans and small fish. It is pigments in some of the crustaceans that give flamingos their distinctive pink color.
Another useful adaptation in flamingos is their ability to drink hot and salty water. During the course of normal feeding, the birds take in salty water, and they will also drink it. They are able excrete the excess salt through special glands next to their beaks.
This adaptation is very unusual among birds, and it allows flamingos to stay in open salty lagoons for long periods to avoid predators, since they do not need to seek out fresh water frequently. These birds do, however, need some fresh water, and in some cases, the only source is from hot springs. Unusually, they are able to drink water at very high temperatures.
Flamingos live in large colonies that may contain tens of thousands of individual birds. As with other animals that live in colonies or herds, this provides protection from predators. The birds are vulnerable when feeding, but in such a large group, some individuals will be alert to any threats and will warn the flock of danger. Flamingos communicate by vocalizing and parents learn to recognize their chicks’ calls, allowing them to be located when a parent has been foraging for food.