The wings of the flightless cormorant are only about one third of the size that would be needed for a bird of its proportions and weight to fly. This species evolved in an island environment that was free of predators. As a result, the bird had no need to fly and eventually became flightless. However, the Galapagos Islands have not remained free of introduced predators, and, consequently, this cormorant is now one of the world's rare birds.