The penguin is one of the most important species dwelling in Anctartica. Find here the main features of this funny sea bird.
The penguin descends from the flying birds specialized in diving. The loss of their capacity to fly and the atrophy of their wings, which are more similar to flippers than to what they really are, is due to their adaptation to the aquatic environment, where they move around with real skill and can reach a speed of 40 km/hour. There are 18 species and 6 genres of penguins, most of which dwell in Antarctica and subantartic islands, such as the Emperor, King, Adelie, Chinstrap, Gentoo, Macarroni and Rockhopper; the rest are distributed in the area of Australia, New Zealand and South Africa. For all classes, the basic diet consists in krill, squids and other small fish.
They are gregarious birds and, both in the sea and on land, they move around in flocks. In the crowded and noisy colonies, they may be watched as they walk in an upright stance with a funny waddling pace resulting from the overlapping of their legs. According to the species, they measure between 38 and 120 centimeters of height, though the Emperor penguin may surpass this size.
The feathers are another adaptation to the sea environment. Similar to scales, their small feathers cover all their body and, in general, they are white in the abdomen and chest and black on the back. This form of adaptation enables them to bear extreme temperatures. The body, relatively smaller than their total volume, provides an excellent preservation of heat, increased in some species by a thick layer of fat that works as thermal isolator. During the summer, they change all their feathers in a short time. As they reduce this natural protection, they remain more time on land and avoid getting into the water to feed.
Team Work
During the mating season, the penguins gather in large colonies in order to reproduce. They choose the same spots their ancestors chose, sometimes located several kilometers away from the ocean. Unlike general belief, they are not monogamous for a lifetime, but they do look for one same partner during each reproduction season. They usually make their nests in burrows or holes in the rock or they might just do it in the open, on the rocks. In the case of the Emperor and the King penguin, they only incubate one egg at a time and they place it over their own legs, covering it with their feathers in order to keep it warm. Both genders are in charge of incubating the eggs and feeding the chicks, which are covered by a greyish plumage when they are born. It is usual to see them take shifts to take care of the nest and go find food which they later regurgitate from their stomach into the beaks of their young.
When the offspring have moved out and developed their first feathers, they get into the sea and search for food themselves. Their natural enemies are the leopard seal and the orcas. The skuas attack the nests that have been neglected in order to steal the eggs or the young. These chicks are usually left alone when their parents go out to search food in the sea and gather in "nurseries" to protect themselves from their predators. It is in this season when we can find them populating the islands and the beaches of the Antartic Peninsula.
Unlike in other times, when they were chased and hunted, today, penguins are studied and protected by international environment preservation regulations. 
