This order contains all species of grebes, which inhabit the calm waters of lakes, ponds and rivers. Some populations migrate to estuaries or coastal waters during the winter. They are excellent divers, feeding on fish, aquatic insects, crustaceans, molluscs and other small invertebrates. Their feet are lobed and each toe is independent of the other, which is an adaptation to their aquatic lifestyle. They form the sister group to the Phoenicopteriformes (pink flamingos). Grebes used to be included in a group that also contained loons called Colymbiformes, now a disused order of birds.