Reptiles (class Reptilia) are cold blooded and have scales or scutes covering their skin. They are four limbed animals and lay eggs. With the exception of Antarctica, reptiles can be found in all the continents. With more than 6,800 species of reptiles present on the earth today, crocodiles and alligators, snakes, turtles and lizards form the major group. As they are cold blooded they keep themselves warm in the sun.

Anatomy of reptiles

All species of reptiles are vertebrates which mean that they have backbones. Dry and horny scales cover the bodies of the reptiles. Besides a few species of lizards and snakes, all other reptiles have four legs and are close to the ground. Each group of reptile has its own characteristic.

Diet of the reptiles

There are various varieties of diets eaten by the different reptiles. Some reptiles eat other animals like slugs and insects and mammals like rabbits and mice. There are species like the striped crayfish snake that eat only crayfish, while there are some species that eat only plants, although these are just a small in number.

Defense of the reptiles

Like all animals, even the reptiles need to defend themselves against enemies. They adopt various ways to defend themselves. These ways range from racing and hiding away to blending in the background or puffing their bodies to even playing dead. Crocodiles are known to be playing dead quite often and fooling their enemies and other animals they prey. Lizards often hide away or blend themselves in the surroundings to defend themselves.

Subspecies and races of reptiles

Although the species of a reptile may be the same, but they look different in different regions. This difference is attributed to the reptile being of a subspecies or race. An example of this is the Milk Snake which has nine subspecies in Canada and the United States. Thus when the reptiles from the same species has different looking reptiles in different regions it is called as a race or subspecies. Although different in some manner, the subspecies can breed with each other to produce young. The subspecies of a reptile are denoted with a name that has three parts. Genus is the first part, the species is the second part and the third part is the subspecies. This can be explained with an example, where the Eastern Milk Snake has the scientific name as Lampropeltis triangulum triangulum and the other subspecies of this, the Scarlet KingSnake has the name as Lampropeltis triangulum elapsoides.

Venomous reptiles

Many of the reptiles like snakes and a few lizards are highly venomous. This means that when they bite they pass on the venom to their victim often killing them in a few seconds. Some of the species of venomous reptiles are the pit vipers (rattlesnakes, cottonmouth and the copperhead), coral snakes, the Gila monster and the Sea Snake. The reptiles usually bite people when they are harassed, otherwise they are known to rarely bite.

Squamata - Squamata, or the scaled reptiles, is the largest recent order of reptiles, including lizards and snakes.

Testudines - Turtles are reptiles of the order Testudines , characterised by a special bony or cartilaginous shell developed from their ribs that acts as a shield.

Crocodylia - Crocodilia is an order of large reptiles that appeared about 84 million years ago in the late Cretaceous Period .

Rhynchocephalia - Sphenodontia, once a wastebin taxon containing a diverse array of unrelated reptiles , today consists of three families: the possibly paraphyletic Gephyrosauridae, the Pleurosauridae, and the Sphenodontidae.