All snakes fall into the category of reptiles. Scientists have so far studied more than 2,400 different kinds of snakes. Only about 8% of them are poisonous. They live on land, under the earth, in the water and on the trees. They are found in almost all parts of the world except in Polar Regions, New Zealand and in some other islands. Snakes are of different sizes and shapes.
The constrictor snakes such as boa and pythons strike their prey with their teeth, and if the prey is large, then they wrap their bodies around it and squeeze until it suffocates.
A snake can swallow large animals without chewing them, because its jaws are loosely attached to the skull and the two halves of the lower jaw are connected only by elastic ligaments (tissues). The mouth can therefore open very wide. By using its many backward pointing teeth the snake can gradually widen its mouth over its prey. In the meantime it breathes by bringing the wind pin opening forward to the front of the mouth. Swallowing and digestion of a large animal may take a long time and some larger snakes probably have only a few meals every year.
The giant 100 kg anaconda snake of the boa family found in South America can swallow a whole pig or deer. In length it is about 10 metres. Due to the huge weight and length, it cannot move much. When some victim passes nearby, it coils its body around and constricts it. It takes several hours to digest the animal. The stomach of snakes produces powerful digestive juices that can break down even big bones of the victim.
