Snakes are invertebrates and cold blooded reptiles with an elongated body. Snakes have the ability to raise and lower their body temperature according to the surrounding environment. These creatures also undergo hibernation, or winter sleep, during the chilling months in caves or deep burrows and come out when the weather is warm enough. There are approximately more than 2700 species across the globe. They are found almost everywhere; in forests, oceans, lakes, streams and deserts. There are different kinds of snakes that can survive on land, in water and on trees. The only places where the snakes cannot be found are the continent of Antarctica, the Arctic circle and high mountainous terrain, where the ground remains frozen all the year round. These reptiles cannot be found in some of the islands in New Zealand and Ireland. Water or sea snakes are not so poisonous as their land counterparts. There are many criteria that must be taken into consideration when it comes to identifying snakes, since each species of snake has its own unique characteristics. One can also identify the different types with the help of pictures. How to Identify Snakes? There are so many species of snakes in the world that almost all look similar to each other and identifying them may look like a daunting task. These reptiles can be categorized according to venomous and non-venomous snakes. However, one of the important facts is that not all species are poisonous since only 10 percent of them have fangs that contain venom. Body Structure Though all snakes have an elongated body, if we observe their body minutely we may notice several differences. Many of them have a slender and long, short and stout body. Some of these reptiles even have body with medium thickness. Adults can grow up to a length of 3 feet. There are also a few species which grow beyond 9 feet. The body is covered with scales but each species has a different pattern. The scales can be smooth or rough and some even have keels, which have a ridge down the middle of the scales. These keeled scales are more stronger and prominent in the male species. There are certain snakes that have a distinct feature on their bodies, like the king cobra which has a hood on the head. Non-poisonous ones have long stripes over their entire body. Another distinct difference between a poisonous and non-poisonous snake is the head. Poisonous snakes have an arrow-shaped, pointed head, whereas non-venomous species have blunt, oval shaped heads. Color The next criterion is color. Many snakes have a uniform color pattern both on the dorsal and ventral side of their bodies. Some also are two toned, one on the surface and the other tone on the belly. The dorsal side (belly) is normally light-colored as compared to the ventral side. Other features that can tell one species of snake from the other are stripes, blotches, cross bands, speckles, rings, diamonds and spots, etc. In some species, the head and neck have distinct markings or colors. Some of the venomous varieties have brightly colored bodies as a sign of warning to enemies. Eyes The eyes have a major role to play when it comes to identifying poisonous snakes. The eyes have an elliptical shaped vertical pupil that is similar to a cat's pupil. In non-poisonous ones, the pupils are round and are situated in the center of the eyes. Venomous snakes have a small depression or pit that is located between the nostrils and the eyes, which acts as heat sensor to detect the nearness of the prey. Hunting Mechanism Snakes are mostly carnivorous, so we know what these cold-blooded reptiles feed on. Different snakes have different mechanism to kill the prey. Some use venom to kill the prey, which is injected into the victim's body through the fangs. Other species like the pythons, boa constrictor, etc. squeeze the prey till it dies. Anacondas, that are very powerful simply grab their prey unawares and then swallow it after overpowering. The jaws are very powerful and elastic. They are attached with the help of hinge like structures and can be expanded according to the size of the prey. Though snakes are one of the most feared creatures by human beings, the fact is that snakes won't harm unless provoked. Some people also keep them as pets. This reptile is now on the list of endangered animals since they are being killed for their skin, which is then imported at high prices. It is our duty to stop this poaching and protect this unique reptile from extinction.