Differences & Similarities of Penguins

Despite the fact that penguins don't fly, they are considered birds. There is some debate about whether there are 16 or 17 different species of penguins existing in the world. However, there are six generally-accepted genera (plural of genus) that differentiate them. These are the Eudyptes Chrysolophus, Pygoscelis, Spheniscus, Megadyptes, Eudyptula and Aptenodytes. Penguins are often used for food, oil, skins, eggs and fish bait.

  1. Similarities of Penguins

    • All penguins have short, weather-proof feathers and modified "wings" (known as flippers) that they use to swim. Penguins are warm-blooded animals and males and females both have only one set of genitalia (one functional testis or one ovary) for reproductive purposes. The females lay eggs. There are virtually no penguins living in the northern hemisphere with the exception of penguins housed at zoos. Few penguins enjoy being handled and tend to bite.

      Penguins lack external ears, which are covered by feathers. They do not have teeth, although they do have a bill which they use to break their egg shells when they hatch. They also have tooth-like barbs in their mouths that assist in the food-swallowing process. Adult penguins feed their young chicks by eating food and then regurgitating it into the chick's mouth.

    Eudyptes Chrysolophus

    • Macaroni Penguins are the most abundant of penguin species. Some penguin experts consider Royal Penguins as a subspecies while others consider them to be a separate species of their own. Their feather plumes are located higher on the forehead. Macaroni penguins lay two eggs; an A-egg and a B-egg. The first laid egg (A-egg) rarely survives. The second laid egg (B-egg) is generally much larger than the A-egg.

    Pygoscelis

    • This species includes the Adelie, Chinstrap and Gentoo penguins. This species mates in colonies that are often massive when compared with other penguin colonies. These penguins can be found in higher areas of the sub-Antarctic and Antarctic regions.

    Spheniscus

    • This species consists of the African, Galapagos, Humboldt and Magellanic penguins. As adults, these penguins have black stripes and have naked skin on their heads. They have strong hooked beaks. In contrast to other penguins, this species often breeds throughout the year. Many are located in climates that are more tropical in nature than where other species of penguins reside including the Galapagos Islands, South America and Africa.

    Megadyptes

    • The Yellow-Eyed Penguin resides only in southern New Zealand. These penguins forage close to shore and don't migrate. In contrast to other species, yellow-eyed penguins maintain nests out of sight from other penguins in their social groups.

    Eudyptula

    • The Little Penguin has many features unique to the species. It is the smallest of all penguin types and is the only species that is nocturnal in nature. It maintains more of a horizontal posture than other penguins.

    Aptenodytes

    • Emperor and King penguins are the largest of the penguins, and they can dive much farther in the water than other penguins. They lay just one egg and do not build nests. Emperor penguins are the only penguins that reside in the high Antarctic.