penguin

Penguins are a group of aquatic, flightless birds in the order Sphenisciformes, comprising about 18 to 20 species. They are found almost exclusively in the Southern Hemisphere, with large colonies on Antarctica and subantarctic islands, and smaller populations along the coasts of South America, Africa, and the Galapagos Islands. Penguins are highly adapted to life in the sea: their wings have evolved into flippers for powerful underwater propulsion, and their bones are denser than in other birds, aiding diving. Their plumage often features a dark back and a white belly, providing counter-shading for camouflage in open water.

Penguins feed mainly on fish, krill, and squid, which they catch while diving. They breed in colonies, often on rocky shores or ice. Most species lay two eggs, though some lay one; males commonly incubate the eggs with a brood patch while females forage. Incubation lasts several weeks, after which chicks hatch and are fed by both parents until they fledge. Penguins are highly social and communicate with vocalizations and visual cues, especially at breeding sites. They molt after the breeding season, replacing all feathers in a few weeks during which they are unable to swim.

Predators include leopard seals and orcas, as well as seabirds that prey on chicks. Humans affect penguin populations through climate change, which alters ice cover and prey distribution, and through fishing and habitat disruption. As a result, several penguin species are listed as threatened or near threatened by the IUCN, though status varies by species. Notable members include the emperor, king, Adélie, chinstrap, Gentoo, macaroni, African, Humboldt, and Galapagos penguins.