The great auks that lived farther north averaged larger in size than the more southerly members of the species.
Great Auk calls included low croaking and a hoarse scream.
The wings were only 15 cm (5.9 in) long, rendering the bird flightless.
Instead, the great auk was a powerful swimmer, a trait that it used in hunting.
Known from bones found in the Yorktown Formation of the Lee Creek Mine in North Carolina, it is believed to have split, along with the great auk, from a common ancestor.
It is unrelated to the birds now known as penguins, which were discovered later and so named by sailors because of their physical resemblance to the great auk.
It bred on rocky, isolated islands with easy access to the ocean and a plentiful food supply, a rarity in nature that provided only a few breeding sites for the great auks.
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.
the flightless great auk was the second-largest member of both its family and the order Charadriiformes, surpassed only by the mancalline Miomancalla.