Ever since I learned about penguins when I was in the 2nd or 3rd grade, I have completely loved them! I'm not sure what exactly what it was that really caught my interest then but I've never found any other animal as interesting as I find penguins. Over the years I've collected a lot of penguin things, from stuffed animals to decorations, calendars, I even have pajamas, slippers, socks, coffee mugs, tins, calculators, pens and pencils, and bookmarks with penguins on them. The first things I always notice in stores are anything that have to do with penguins, and sometimes its pretty hard to convince myself not to buy something I don't need just because it has a penguin on it! I have even had an idea in my head for a long time about a book that features a not-so-evil penguin (who thinks he's an evil genius) that wears a top hat and monocle.


Penguins are one of the many flightless birds that live in our world, with between 17 and 20 living species today (there are debates over sub species of certain penguins, which is why the number is between 17 and 20). Penguins may have a slight disadvantage being unable to fly, but they are adapted incredibly well for aquatic life. Diving penguins are able to reach speeds of 6 to 12 km/h (3.7 to 7.5 mph), and some of the larger penguins are known to stay underwater for as long as 22 minutes at a time, whereas the smaller species of penguins are known for only staying underwater for up to 2 minutes. Smaller species of penguins typically don't need to dive very deep, as most of their food can be found near the surface of the water.


Since penguins will spend half of their life underwater it's important that they keep warm, which is why they have a layer of thick insulating feathers (heat loss is much greater under water than it is in the air) and underneath that is a layer of air to help keep the penguins buoyant. Many people think that all penguins live in the cold Antarctica, but even though penguins are native to the southern hemisphere, there are some that live in warmer areas such as Australia, New Zealand, South America and even South Africa.

The largest living species is the Emperor Penguin (Aptenodytes forsteri): adults average about 1.1 m (3 ft 7 in) tall and weigh 35 kg (75 lb) or more. The smallest penguin species is the Little Blue Penguin (Eudyptula minor), also known as the Fairy Penguin, which stands around 40 cm tall (16 in) and weighs 1 kg (2.2 lb). Among extant penguins, larger penguins inhabit colder regions, while smaller penguins are generally found in temperate or even tropical climates (see also Bergmann's Rule). Some prehistoric species attained enormous sizes, becoming as tall or as heavy as an adult human (see below for more). These were not restricted to Antarctic regions; on the contrary, subantarctic regions harboured high diversity, and at least one giant penguin occurred in a region not quite 2,000 km south of the equator 35 mya, in a climate decidedly warmer than today.

Breeding

Penguins for the most part breed in large colonies, the exceptions being the Yellow-eyed and Fiordland species; these colonies may range in size from as few as a 100 pairs for Gentoo Penguins, to several hundred thousand in the case of King, Macaroni and Chinstrap Penguins. Living in colonies results in a high level of social interaction between birds, which has led to a large repertoire of visual as well as vocal displays in all penguin species.Agonistic displays are those intended to confront or drive off, or alternately appease and avoid conflict with, other individuals.
Penguins form monogamous pairs for a breeding season, though the rate the same pair recouples varies drastically. Most penguins lay two eggs in a clutch, although the two largest species, the Emperor and the King Penguins, lay only one. With the exception of the Emperor Penguin, in all penguins share the incubation duties.These incubation shifts can last days and even weeks as one member of the pair feeds at sea.
Penguins generally only lay one brood; the exception is the Little Penguin, which can raise two or three broods in a season.
Penguin eggs are smaller than any other bird species when compared proportionally to the weight of the parent birds; at 52 g (2 oz), the Little Penguin egg is 4.7% of its mothers' weight, and the 450 g (1 lb) Emperor Penguin egg is 2.3% The relatively thick shell forms between 10 and 16 % of the weight of a penguin egg, presumably to minimise risk of breakage in an adverse nesting environment. The yolk, too, is large, and comprises 22–31 % of the egg. Some yolk often remains when a chick is born, and is thought to help sustain it if parents are delayed in returning with food.
When mothers lose a chick, they sometimes attempt to "steal" another mother's chick, usually unsuccessfully as other females in the vicinity assist the defending mother in keeping her chick. In some species, such as Emperor Penguins, young penguins assemble in large groups called crèches.