Penguins is Family Spheniscidae. Spheniscidae includes all penguins, living and extinct, and is the only Family in the Order Sphenisciformes
Scientists recognize 40 or more species of extinct penguins. Scientists believe that penguins evolved from flying birds at least 65 million years ago during the Cretaceous Period. As the ancestors of penguins became adapted to an oceanic environment, structural changes for diving and swimming led to the loss of flying adaptations. To date, the discovery of all penguin fossil fragments has been limited to the Southern Hemisphere. Records show that prehistoric penguins were found within the range of present-day penguins.
a. The earliest penguin fossil fragments were found in New Zealand in the mid-1800’s. The oldest penguin fossils date from 58 to more than 60 million years ago.
b. Fossil records show that the largest extinct species lived in the Miocene Period (11 to 25 million years ago). Pachydyptes ponderosus probably stood 1.4 to 1.5 m (4.5 –5 ft.) and may have weighed 90 to 135 kg (198–298 lb.). Anthropornis nordenskjoldi probably stood 1.5 to 1.8 m (5–5.9 ft.) and weighed 90 to 135 kg (198–298 lb.). Measurements are estimates, since only a few bone fragments have been found.
The extinct species of penguins began disappearing during the Miocene, about the same time that the number of prehistoric seals and small whales started increasing in the oceans. One hypothesis is that seals, whales, and penguins may have competed for the same food source. Another hypothesis is that penguins could have become prey for some of these other predators. Both factors may have contributed to their extinction.
Penguins share molecular and morphological characteristics with birds in the Order Procellariiformes (the albatrosses, shearwaters, and petrels), the Order Gaviiformes (loons and grebes), and frigatebirds (Order Pelecaniformes). The first European explorers to see penguins probably were part of the Portuguese expedition of Bartholomeu Dias de Novaes in 1487–1488. They were the first to travel around what is now known as the Cape of Good Hope in southern Africa.
The first documentation of penguin sightings is credited to members of the Portuguese voyage of Vasco de Gama to India in 1497. They described penguins (African) they saw along the southern coasts of Africa. The discovery of South America’s Magellanic penguin was chronicled during the journey of Spanish explorer Ferdinand Magellan in 1520.
The origin of the word “penguin” has been a subject of debate. The theories of researchers and historians range from references to the amount of fat (penguigo in Spanish and pinguis in Latin) penguins possess to the claim that the word was derived from two Welsh words meaning “white head.” The most agreed-upon explanation is that “penguin” was used as a name for the now-extinct great auk, which the modern-day penguin resembles and for which it was mistaken.
DistributionPenguins All 17 species of penguins live in the Southern Hemisphere. See Appendix on page 30 for information on distribution for each species. Penguins are found on every continent in the Southern Hemisphere. They are abundant on many temperate and subantarctic islands.
Penguins HabitatPenguins generally live on islands and remote continental regions free from land predators, where their inability to fly is not detrimental to their survival. These highly specialized marine birds are adapted to living at sea some species spend as much as 75% of their lives at sea. Penguins are usually found near nutrient-rich, cold-water currents that provide an abundant supply of food. Different species thrive in varying climates, ranging from Galápagos penguins on tropical islands at the equator to emperor penguins restricted to the pack ice of Antarctica.
The seasons of the Southern Hemisphere are opposite those of the Northern Hemisphere. When continents above the equator experience spring and summer, the areas below the equator experience fall and winter.
Penguins MigrationAdult penguins usually disperse from breeding rookeries to feed in coastal waters. Studies have found that adult emperor, Magellanic, and Humboldt penguins travel long distances between feeding and breeding grounds. Young birds usually disperse when they leave their colonies and may wander thousands of kilometers. They generally return to the colonies where they were hatched to molt and breed.
Penguins PopulationPenguins Population data usually are gathered during the breeding season. Some researchers count chicks to estimate the total population, others count breeding pairs. The Appendix on page 30 lists population estimates by species. Chinstrap penguins may be the most numerous, with a population estimated at 4 million breeding pairs. (Bird Life International, 2005).
Genus, Species Most scientists recognize 17 species of penguins:
• Emperor Penguins, Aptenodytes forsteri
• King Penguins, Aptenodytes patagonicus
• Adélie Penguins, Pygoscelis adeliae
• Gentoo Penguins, Pygoscelis papua
• Chinstrap Penguins, Pygoscelis antarctica
• Rockhopper Penguins, Eudyptes chrysocome
• Macaroni Penguins, Eudyptes chrysolophus
• Royal Penguins, Eudyptes schlegeli
• Fiordland crested Penguins, Eudyptes pachyrhynchus
• Erect-crested Penguins, Eudyptes sclateri
• Snares Island Penguins, Eudyptes robustus
• Yellow-eyed Penguins, Megadyptes antipodes
• Fairy Penguins (also known as little blue), Eudyptula minor
• Magellanic Penguins, Spheniscus magellanicus
• Humboldt Penguins, Spheniscus humboldti
• African Penguins (formerly known as black-footed), Spheniscus demersus
• Galápagos Penguins, Spheniscus mendiculus