With their legs set far back for efficient movement underwater, the penguins walk awkwardly in a very upright position. However, penguins are rarely seen underwater, so our main impression of them is confined to how they appear on land. Underwater they are every bit as fearsome to their prey as lions are to theirs! Unlike flying birds, their bones are dense to make diving easier. They are excellent divers, descending to depths of over 250 metres, though most of their dives will be in the top 10 metres. To catch their breath and to save energy while swimming, they leap clear of the water every few metres. Their cruising speed in water is about 10km per hour. Their legs are set far back in the body, and together with the tail form an underwater rudder to their perfectly streamlined bodies. Penguin wings are stiff, short flippers to propel them underwater - they literally fly through the sea.
Some species spend 75% of their time at sea - the most of any birds. Instead, they have evolved into the most efficient swimmers and divers of all birds. Some fossil penguins were larger than the ones that exist today, with one species almost as tall as a man (170cm).Īlthough they have wings and feathers, penguins cannot fly. There were at least 25 species, many of which have become extinct.
But they were wrong - penguins are highly evolved to be able to live in the coldest of places.įossil records show that penguins evolved from flying birds (petrels) about 50 million years ago. Members of Captain Scott’s famous expedition went on what they described as “the worst journey in the world” in the Antarctic winter to obtain an emperor penguin embryo to prove this point.
Penguins were once thought to be the most primitive of birds. The name penguin was first given to another type of bird, the auk (also a large, flightless, black and white bird). No one knows for sure. It could come from the Welsh ‘pen gwyn’, which means ‘white head’, or from the Latin ‘pinguis’, referring to the fat or blubber of the bird. Heat exchangers at the top of their legs take heat from the blood flowing to the feet, and use it to heat up the blood flowing back into the body. Blood flow to their feet is tightly controlled, with reduced flow in cold conditions. Penguins stand for hours on ice, but they have two clever ways of keeping their feet the right temperature – a few degrees above freezing. The distinctive colours and features of each penguin species are on their heads and neck - some are black and white, some have yellow patches, and others have elaborate coloured eyebrows.Īll penguins have similar body form and structure, but they vary greatly in size, from the little penguin weighing 1.1kg and about 40cm tall, to the emperor penguin, which weighs up to 40kg and is about 115cm tall. The basic penguinĪntarctic penguins have a striking black and white coat. The real home of all penguins is the cooler waters of the Southern Hemisphere.
One species, the Galapagos penguin, even lives on the equator. King penguins only breed on the warmer more northerly subantarctic islands. However, of the 18 different species of penguin, only two ( emperor and Adélie) make the Antarctic continent their true home, although others ( chinstrap, gentoo and macaroni) breed on the northern tip of the Antarctic Peninsula, where conditions are less harsh. Living in colonies with populations larger than some cities, and surviving in the harshest of conditions, it is no wonder that penguins are seen as the emblem of Antarctica. Penguins are the most common birds in the Antarctic.
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