Most penguins feed on krill, fish, squid and other forms of sea life which they catch while swimming underwater.

You can find plenty of penguins in Antarctica, but there are no penguins living at the North Pole or any other part of the Arctic. In fact, the birds live almost exclusively in the Southern Hemisphere.

The Galápagos penguin (Spheniscus mendiculus) is endemic to the Galápagos Islands. The cool waters of the Humboldt and Cromwell Currents allow it to survive despite the tropical latitude.

While hunting, the species can remain submerged around 20 minutes, diving to a depth of 535 m (1,755 ft). It has several adaptations to facilitate this, including unusually structured hemoglobin to allow it to function at low oxygen levels, solid bones to reduce barotrauma, and the ability to reduce its metabolism and shut down non-essential organ functions.

Most penguins swim underwater at around four to seven miles per hour (mph), but the gentoo penguin (Pygoscelis papua) can reach top speeds of 22 mph!

A group of penguins on land is called a waddle. A similar group in the water is called a raft.

According to the Guinness Book of World Records, the largest colony of penguins on earth is found on Zavodovski Island in the South Sandwich Islands (Antarctica) where approximately two million chinstrap penguins breed.

Most vertebrates can taste five different flavors: sweet, bitter, sour, salty and savory. Most birds are limited to just four flavors, omitting the sweet sense. But penguins have an even more limited palate. Scientists at the University of Michigan have found the aquatic birds can only taste two flavors: sour and salty.

The little blue penguin (Eudyptula minor) stands around 33 cm (13 in) tall and weighs 1 kg (2.2 lb). In Australia, it is often called a fairy penguin because of its small size.

There are generally acknowledged to be 17 different species of penguin living in the world today.