Penguins are flightless sea birds of the Southern Hemisphere.
In all, there are 18 species of penguins, found in South Australia, New Zealand, and off the coasts of Peru, Chile, and South Africa. Some species live as far north as the equatorial Galapagos Islands, but they are primarily cold-weather birds. The Adelie and the Emperor are the two true Antarctic species. Penguins have a heavier skeleton than most birds, waterproof feathers, and specialized glands that extract and excrete excess salt. Their feathers, which even cover their bills and feet, combine with a thick layer of fat to insulate them.