Great auk (Pen Gwyn in Welsh), or, because the great auk had such large white circles on its head. When European explorers discovered what today are known as penguins in the Southern Hemisphere, they noticed their similar appearance to the great auk and named them after this bird, although biologically, they are not closely related. Whalers also lumped the northern and southern birds together under the common name "woggins". Standing about tall and weighing approximately as adult birds, the flightless great auk was the second-largest member of both its family and the order Charadriiformes, surpassed only by the mancalline "Miomancalla". The great
Flightless bird 85–92 days while females feed. They can go up to a week without eating and survive only off fat stores. The emu has been documented fasting as long as 56 days. If no continued pressures warrant the energy expenditure to maintain the structures of flight, selection will tend towards these other traits. Many flightless birds are extinct; this list shows species that are either still extant, or became extinct in the Holocene (no more than 11,000 years ago). Extinct species are indicated with a dagger (†). A number of species that are suspected, but not confirmed to be flightless, are