Why Do Penguins Have Wings

There is a limit to the size of a bird that uses its wings for flying both in the air and the water. Auks in the northern hemisphere do this and they fill the same ecological niche in the northern hemisphere as penguins do in the southern hemisphere. Auks use their wings both for flying in the air and for propulsion in the water. The largest living auk is one of the guillemots which is the same size as the Little penguin, the smallest of the penguins. There was an auk, the Great Auk, which was about the size of a gentoo penguin and was flightless but used its wings as a penguin uses its flippers. The Great Auk became extinct in the 19th century.