A gland near the base of its tail provides waterproof oil. Penguins spend several hours each day covering their feathers with this oil and give extra attention to the task before swimming. Some species of penguins can march up to about 60 miles across sea ice to get to their breeding grounds.
Penguin feet are also adapted to help the birds steer while swimming. They use their feet like rudders, angling them to help control direction. This streamlined design helps penguins swim fast. Penguins seem a bit out of place on land, with their stand-out black jackets and clumsy waddling. April 25 of each year is World Penguin Day , and to celebrate here are 14 facts about these charismatic seabirds. Depending on which scientist you ask, there are 17 — 20 species of penguins alive today, all of which live in the southern half of the globe.
The most northerly penguins are Galapagos penguins Spheniscus mendiculus , which occasionally poke their heads north of the equator. Just before taking flight, they release air bubbles from their feathers. This cuts the drag on their bodies, allowing them to double or triple their swimming speed quickly and launch into the air. Most penguins swim underwater at around four to seven miles per hour mph , but the fastest penguin—the gentoo Pygoscelis papua —can reach top speeds of 22 mph!
From above, their black backs blend into the dark ocean water and, from below, their white bellies match the bright surface lit by sunlight. This helps them avoid predators, such as leopard seals , and hunt for fish unseen. Many believe that the dark back and white belly serve as camouflage when they are underwater - but if you've ever looked at an underwater photo of a penguin you'd soon realise that this is not very effective. In fact, ancient penguins were red and grey - far better deep-water camouflage.
African penguins' black and white tuxedo colouration has a few other uses :. Have you ever opened your eyes underwater and noticed how blurry your eyesight becomes, and how the water stings your eyes?
Well, penguins don't have this problem! Penguins' corneas are flattened by strong muscles around their eyes, which prevents the light from bending when it enters their eyes and blurring the image underwater. They also have an extra, transparent eyelid called a nictitating membrane that keeps the saltwater out shysharks have them too , by the way. It's almost like they are wearing a scuba mask all the time. African penguins are an excellent example of something conservationists call " charismatic megafauna ": big, lovable animals that inspire people to support conservation, which aids the species' entire environment and the "less adorable" species it shares this environment with.
Human beings can hear sounds as low as 20Hz the rumble of a far-away truck and as high pitched as 20 Hz so high your cellphone speaker can't produce it. Compared to the flat ear holes of penguins, our relatively giant ear cones are exceptionally good at catching sound, allowing us to determine the direction sound is coming from, and its distance away - useful skills for a land animal.
Penguins' hearing seems much more basic, as they can only hear Hz to 15 Hz, and their small heads and flat ears limit their ability to detect the direction of sound. However, penguins are exceptional at telling frequencies apart - they have the ability to hear the exact call of their chick or mate amongst tens of thousands of other penguins.
Especially important considering their "language" has so few words. African penguins return to the same breeding site every year, with mates reestablishing their existing pair bond.
They will only begin to look for a new partner if their mate dies, or does not return during the breeding season. We know that humans can see amazing colour, while animals like dogs are "colourblind". Well, compared to an African penguin, we humans are colourblind too. We see colour because of cells in the back of our eyes called cones, which detect certain types of light. Humans have three types of cones for seeing our primary colours - red, blue and green. Penguins have an extra cone that allows them to see ultraviolet light - so to them our UHD TVs would look as awful as old black and white TVs looked to us.
African penguins and their close relatives dig burrows that they then decorate with bits of debris. Unfortunately, with the destruction of South Africa's guano islands, there is no longer anywhere for them to burrow as sand tends to collapse.
Everyone celebrate — April 25 is World Penguin Day! Want to test your penguin knowledge? Take our quiz! The different species range from the smallest blue or fairy penguin about 41 centimetres tall and 1 kilogram in weight to the largest emperor penguin about 1. The smaller penguin species live closer to the equator where it is warm, and eat mostly fish. The larger penguins live closer to Antarctica where their large size can better handle the very cold and windy weather.
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