Auks

Auks, members of the family Alcidae, are a group of seabirds that includes murres, guillemots, puffins, and others, totaling 25 species across 11 genera. While they can fly, they are perhaps best known for their "flying" underwater, using their wings to swim in a way similar to penguins, with whom they are not closely related. Auks exhibit a black-and-white coloration and are adept at diving, commonly compared to penguins in their feeding behaviors. However, their ability to walk on land is rather awkward and clumsy. A notable distinction among these birds is their monomorphic nature, meaning males and females have similar appearances. Regarding size, they range from the small least auklet to the larger thick-billed murre. Distinct names for auks exist between Europe and North America; for example, "murres" in North America are known as "guillemots" in Europe, while Europe's "little auk" is North America's "dovekie." Auks are pelagic, spending much of their lives out at sea and coming ashore predominantly for breeding, with monogamous and often lifelong pair bonds. Some auks breed in large colonies on cliffs, while others prefer burrows or smaller group settings. Despite their modern limited geographical distribution, auks have a rich fossil record that suggests a greater past diversity and hints at their evolutionary journey from shorebirds to adept diving seabirds. Genetic studies indicate they are related to skuas and have adapted over time to cooler northern waters, their pursuit diving feeding methods proving less efficient in warmer temperatures. Losses of species in the Atlantic compared to the Pacific point to historical extinctions rather than present-day distributional restraints. The family's systematics includes several subfamilies and tribes, with various genera housing only a few species, reflective of their specialized ecological niches and restricted geographical range.