Penguin Penguin Penguins (order Sphenisciformes, family Spheniscidae) are a group of aquatic, flightless birds. They live almost exclusively in the Southern Hemisphere, with only one species, the Galapagos penguin, found north of the equator. Highly adapted for life in the water, penguins have countershaded dark and white plumage, and their wings have evolved into flippers. Most penguins feed on krill, fish, squid and other forms of sea life which they catch while swimming underwater. They spend roughly half of their lives on land and the other half in the sea. Although almost all penguin species are native to the Southern Hemisphere,
Palaeognathae flying birds that were common in the Cenozoic of the northern hemisphere, were also paleognaths. He argues that the lithornithiform bird "Paleotis", known from fossils in Denmark (northern hemisphere), shared unique anatomical features of the skull that make it a member of the same order as the ostriches. He also argued that the kiwis should not have reached New Zealand, which moved away from the mainland in the Early Cretaceous, if their ancestor was flightless; this claim at least has been vindicated by the discovery of the possibly volant "Proapteryx". He therefore deduced that lithornithiform ancestors could have reached the