Penguins (order Sphenisciformes, family Spheniscidae) are flightless birds found in the southern hemisphere.

Species and habitats

There are 17 to 18 species known worldwide, depending on whether the two Eudyptula species are counted as distinct. Even though all penguin species are native to the southern hemisphere, they are not found only in cold climates, such as Antarctica. In fact, only a few species of penguin actually live so far south. There are three species that live in the tropics; one lives as far north as the Galápagos Islands and will occasionally cross the equator while feeding.

The largest species is the Emperor Penguin (Aptenodytes forsteri): adults average about 3 ft 7 in (1.1 meters) tall and weigh 75 lb (35 kilograms) or more. The smallest known penguin species is the Little Blue Penguin (also known as the Fairy Penguin), which stands around 16 in tall (40 cm) and weighs 2.2 lb (1 kg). Larger penguins retain heat better, and thus inhabit colder regions while smaller penguins are found in temperate or even tropical climates. The rarest type of penguin is the yellow-eyed penguin (megadyptes antipodes) and is probably the most ancient of all living penguins. Adults average about 65cm tall and the adult’s average weight is 5-6 kilograms

Most penguins have a diet that consists of krill, fish, squid, and other forms of sea life caught while swimming underwater. They spend half of their life on land and half in the oceans.

Penguins are one of the few species on the planet whose females fight over single males during mating season, due to the low number of male penguins.

One of the most baffling forms of behavior comes when a mother loses her chick, either due to its being unable to endure its first storm, or due to other reasons such as predators. When a mother loses its chick, they have been known to actually attempt to steal another mother’s living chick – presumably in order to deal with the grief of the loss. This behavior has amazed scientists, as it is an emotional outburst as opposed to an instinctual behavior; something many animals do not exhibit when losing their young. Many have used this as prime evidence for decades that many animals have near human-like emotions and feelings, often for the sake of animal rights. Interestingly, the other females in the penguin groups dislike this behavior and will help the defending mother keep her chick. Another fact about penguins is that they are one of the few species of birds that seem to have no fear of people. In fact, they have been known to approach groups of explorers without the slightest hesitation.


The oldest fossils of penguins emerged in the Eocene era more than 40 million years ago. These fossils proved that prehistoric penguins were already flightless and seagoing, so their origins may go as far back as 65 million years ago.


Penguins are superbly adapted to an aquatic life because their wings have become flippers, thus useless for flight in the air. In the water, however, penguins are astoundingly nimble. Within their silky plumage is a layer of air which is preserved, ensuring buoyancy. This air layer also helps to insulate the bird while swimming in the icy waters of the Antarctic. In tropical and temperate zones the plumage of penguins is much thinner.

On land, penguins use their tails and wings to maintain balance for their upright stance.

All penguins have a white underside and a dark (usually black) upper side which gives the bird camouflage. A predator looking up from below (such as an orca or a leopard seal) has difficulty distinguishing between a white penguin belly and the reflective water surface. The dark plumage on their backs camouflages them from above.

Diving penguins reach 6 to 12 km/h, though there are reports of velocities of 27 km/h (which are probably realistic in the case of startled flight). The smaller penguins do not usually dive very deep. Instead they catch their prey near the surface in dives that normally last only one or two minutes. Larger penguins, however, can dive deeper if needed. The Emperor Penguin has been recorded reaching a depth of 1500 feet (450 meters) and staying submerged for 18 minutes.

Penguins either waddle on their feet or slide on their bellies across the snow, a movement called “tobogganing.” Tobogganing allows the penguin to conserve energy and move relatively fast at the same time.

Penguins have an excellent sense of hearing. Also, their eyes are adapted for underwater vision, and are their primary means of locating prey and avoiding predators. In the air, however, they are thought to be nearsighted. Their sense of smell has not yet been researched.

A gland near their eyes filters excess salt from the bloodstream, allowing them to drink salt water safely. The salt is then excreted in a concentrated fluid from the nasal passages.

Penguins have no external genitalia therefore chromosome testing must be done in order to determine a penguin’s sex.

Mating Habits

Some penguins mate for life, while others for just one season. They generally raise a small brood, and the parents cooperate in caring for the clutch and for the young.

Male bonding behavior

In early February 2004 the New York Times reported a male pair of chinstrap penguins in the Central Park Zoo had partnered and even successfully hatched a female chick from an egg. Other penguins in New York have also been reported to be forming same-sex pairs.

This was the basis for the children’s picture book “And Tango Makes Three.” The couple about whom the book was based, Silo and Roy, would see further interesting developments in their relationship when, in September 2005, Silo left Roy, for a female penguin only to come back to Roy in a few weeks.

Zoos in Japan and Germany have also documented male penguin couples. The couples have been shown to build nests together and use a stone to replace an egg in the nest. Researchers at Rikkyo University in Tokyo found twenty such pairs at sixteen major aquariums and zoos in Japan. Bremerhaven Zoo in Germany attempted to break up the male couples by importing female penguins from Sweden and separating the male couples; they were unsuccessful. The zoo director stated the relationships were too strong between the couples.


Family Spheniscidae

  • King Penguin, Aptenodytes patagonicus
  • Emperor Penguin, Aptenodytes forsteri
  • Gentoo Penguin, Pygoscelis papua
  • Adelie Penguin, Pygoscelis adeliae
  • Chinstrap Penguin, Pygoscelis antarctica
  • Rockhopper Penguin, Eudyptes chrysocome
  • Fiordland Penguin, Eudyptes pachyrhynchus
  • Snares Penguin, Eudyptes robustus
  • Royal Penguin, Eudyptes schlegeli
  • Erect-crested Penguin, Eudyptes sclateri
  • Macaroni Penguin, Eudyptes chrysolophus
  • Yellow-eyed Penguin, Megadyptes antipodes
  • Little Penguin (Blue or Fairy Penguin), Eudyptula minor
  • White-Flippered Penguin, Eudyptula albosignata
  • African Penguin (Jackass Penguin), Spheniscus demersus
  • Magellanic Penguin, Spheniscus magellanicus
  • Humboldt Penguin, Spheniscus humboldti
  • Galápagos Penguin, Spheniscus mendiculus

PHOTO CAPTION: Chinstrap Penguin, Pygoscelis antarctica (US National Oceanic and Atmospheric Administration)


The name Penguin is thought by some to derive from the Welsh words pen (head) and gwyn (white), applied to the Great Auk, which had a conspicuous white patch between the bill and the eye (although its head was black), or from an island off Newfoundland known as “White Head” due to a large white rock. This may be, a false etymology created by Dr John Dee in his book on Prince Madoc of Wales, supposedly one of the discoverers of America. By this Dee hoped to cement Queen Elizabeth I’s claim, as a Tudor, to the New World. This theory is also undermined by the fact that penguins live nowhere near Newfoundland, nor do they generally have white heads. According to another theory, the original name was pen-wing, with reference to the rudimentary wings of both Great Auks and penguins. A third theory is that penguin comes from the Latin pinguis (fat). This is the most probable theory, because of proof in two other Germanic languages: Dutch ‘pinguïn’ and German ‘Pinguine’ both have the ‘i’ vowel too. While it has been replaced by an ‘e’ in the English spelling, it can still be heard. It is therefore quite absurd to look for a Welsh origin of the word, solely on the basis of the spelling. By simply looking at the word’s pronunciation and comparing that to the Dutch and German words, one can assume a common Latin borrowing into these Germanic languages – after the first Germanic sound shift (500-200 BC) that makes a PIE ‘p’ into a ‘f’, of course.

Penguins in popular culture

Penguins are popular around the world mainly for their unusually upright, waddling pace and lack of fear towards humans. Their remarkable black and white plumage is often likened to a tuxedo suit and generates humorous remarks about the bird being “well dressed”.

Perhaps in reaction to this cutesy stereotype, fictional penguins are occasionally presented as grouchy or even sinister. The popular Sanrio character Badtz Maru is an example, being cute yet somewhat surly. Feathers McGraw is a wanted criminal. The 1960s television cartoon character Tennessee Tuxedo would often escape the confines of his zoo with his partner, Chumley the walrus. Also, the webcomic Fluble features an enormous penguin conspiracy run by numerous diabolical, if often inept, penguins. In the children’s movie Madagascar (film), the penguins are cast as spies. In the animated series “Wallace and Gromit”, a penguin disguises himself as a chicken to steal a pair of robotic pants. Penguins are often portrayed as friendly and smart as well. Another example is in the anime Neon Genesis Evangelion, which features a warm-water penguin named Pen Pen.

Penguins and Polar Bears: The Misconception

Despite what commercials and other sources may show, the likelihood of a meeting between a penguin and a polar bear without human intervention is small. This is because the two species are found on opposite hemispheres. Polar bears inhabit the northern hemisphere, while penguins mainly inhabit the southern hemisphere. This is a misconception that is fueled by popular culture such as movies and television. A prominent example of this takes place in a Holiday 2005 ad campaign by Coca-Cola featuring the partying penguins and the polar bears watching from afar.