| An auk or alcid is a bird of the family Alcidae in the order Charadriiformes. |
| The alcid family includes the murres, guillemots, auklets, puffins, and murrelets. |
| Closely related to the Tufted Puffin, the Rhinoceros Auklet is a large alcid with a wedge-shaped head. |
| The oldest alcid fossil is Hydrotherikornis from Oregon dating to the Late Eocene while fossils of Aethia and Uria go back to the Late Miocene. |
| In the early 19th century another alcid, the great auk, still inhabited the North Atlantic waters. |
