PENGUIN
Class: AVES
Order: SPHENISCIFORMES
Family: SPHENISCIDAE

This group contains sea-bound birds, almost entirely found in the southern hemisphere. The penguin has diverged into six major genera, all representatives, bar one, are native to the southern hemisphere. The largest penguin, the Emperor Penguin, stands at a metre and a half tall, but the smallest of all, the little penguin, only stands at a mere 30 centimetres. Most penguin species measure in height about an average of this. Smaller penguins prefer habitats where rocks and stones are abundant, and some of these dig burrows. The largest penguins are too large to dig burrows, and are largely terrestrial, occasionally aquatic birds.
I. PENGUIN EVOLUTION
Exactly where the penguin fits into bird classification is rather debated, and so there is a fair amount of speculation as to the precise ancestry of the penguin. However, the oldest known penguins are some 62 million years old, and perhaps looked more like straight-beaked cormorants than modern penguins. Originating around New Zealand, they would soon move throughout the southern hemisphere, and produce a variety of different builds. The largest penguins of which existed grew to almost 2 metres in height, living some 35 million years ago, but 25 million years ago, these would disappear. Today, there are six genera of living penguins - the genus Aptenodytes contains the 'great penguins' - the king and emperor penguins, which are considered most similar to the original penguins. The penguins of genus Pygoscelis are occasionally known as 'brush-tail penguins' for their relatively long tails. The penguins of genus Spheniscus are known as 'banded penguins', and all have similar patterning. Penguins of genus Eudyptes all look relatively similar, with vivid yellow crests, and orange beaks. The smallest penguins belong to the genus Eudyptula, which only grow to about 30 cm in height, aptly named 'Little Penguins'. There is only one living species in the genus Megadyptes, the Yellow-eyed Penguin. Of all penguin species, only one has become somewhat native to the Northern hemisphere - as the Galapagos Penguin's range extends northwards.


