On this Wikipedia the language links are at the top of the page across from the article title. They spend roughly half of their lives on land and the other half in the sea. The word penguin first appears in literature at the end of the 16th century. The penguin valentines gift of the word penguin is still debated.

The birds currently known as penguins were discovered later and were so named by sailors because of their physical resemblance to the great auk. Despite this resemblance, however, they are not auks, and are not closely related to the great auk. Like its relatives, a neatly bi-coloured species with a head marking. The closed neck collar denotes this species. The number of extinct penguin species is debated. Depending on which authority is followed, penguin biodiversity varies between 17 and 20 living species, all in the subfamily Spheniscinae. Pygoscelis antarcticus -Cooper Bay, South Georgia, British Overseas Territories, UK-8.

1943 resulted in the genus being placed in Accipitridae. Some recent sources apply the phylogenetic taxon Spheniscidae to what here is referred to as Spheniscinae. The evolutionary history of penguins is well-researched and represents a showcase of evolutionary biogeography. Although penguin bones of any one species vary much in size and few good specimens are known, the alpha taxonomy of many prehistoric forms still leaves much to be desired. New Zealand and Byrd Land, Antarctica. The oldest known fossil penguin species is Waimanu manneringi, which lived in the early Paleocene epoch of New Zealand, or about 62 mya. Perudyptes from northern Peru was dated to 42 mya.