Crocodiles, Lizards, Turtles and Snakes

Because of their long, powerful bodies and sharp teeth, crocodiles are among the most dangerous predators. When they are small, they eat small fish, frogs and insects. When fully grown, however, they can devour large animals and even humans. Did you know that lizards are the most numerous reptiles in the world today? This group includes a wide variety of species of all shape and sizes. Discover the amazing world of snakes, what they are like inside, where they live, and how they hunt their prey as why some eat only eggs and others have no suffocate their prey by coiling around it. Although people may think that turtles are peaceful creatures, many are actually carnivorous hunters that eat small invertebrates, fish and even some larger animals.

Lizards

Lizards are the largest group of reptiles. They live in most environment except for extremely cold regions, because they cannot regulate their own body temperatures. There are land-dwelling, undergound, tree-dwelling, and even semiaquatic lizards. They can walk, climb, dig, run and even glide. Lizards often have differentiated heads, movable eyelids, a rigi lower jaw, four five-toed feet, a long body covered with scales and a long tail. Some can even shed their tails when threatened.

Komodo Dragon

This animal is the largest lizard in the world. It is related to monitor lizards and can grow up to 3 m(10 ft) long and weigh up to approximately 150 kg (330 lb). These endangered lizards live only on a group of islands in Indonesia. They are carnivorous and are known for their ferocity in attacking their prey. Their saliva is full of bacteria that can kill their prey with only one bite. They can detect other komodo dragons from several miles away.

Changing Colours

Chameleons are well known for their ability to change colour. Another interesting fact is that their tongue can stretch great distances in seconds. They live mostly in africa. Their prehensile tails and toes make them excellent climbers. Another helpful characteristic is that their eyes can move independently of one another, balance and to hide among the leaves.

Venerated and Feared

Crocodiles - along wot their relatives, the alligators, caimans and gavials - are very ancient animals. They belong to the same groups that included the dinosaurs and have changed very little in the last 65 million years. They can go for long periods without moving; during these times they sun themselves or rest in the water. However, they can also swim, jump and even run at high speed to attack with force and precision. In spite of their ferocity, female crocodiles provide more care for their young than any other living group of reptiles.

Slow but Steady

Since their appearance on earth 230 million years ago, turtles have changed very little. Turtles can live on land, in fresh water or in salt water. However, they all need light and heat to survive, and they all lay their eggs on land. Although aquatic turtles are nearly all carnivorous, some land-dwelling species are herbivorous. Turtles' most noticeable trait is their hard shell, which encloses and protects the soft part of their bodies, It also camouflages them for protection from predator species.

Internal Structure

Snakes are scary reptiles with long bodies and no legs. Some are poisonous, but others are not. Like all reptiles, they have a spinal column and a skeletal structure composed of a system of vertebrae. The anatomical differences between species reveal information about their habitats and diet - climbing snakes are long and thin, burrowing snakes are shorter and thicker and sea snakes have flat tails that they use as fins.

Deadly Embrace

Snakes have developed a wide range of techniques to kill their prey. For example, both boas and phytons are powerful constrictors, meaning that they kill by asphyxiating their prey rather than poisoning them with venom. Although boas and phytons belong to the same category of snakes (a catergory that includes the largest species in the world, the famous anaconda and reticulated phyton of Africa and Asia), their reproductive systems differ from one another. Their large size makes them heavy and slow moving, so they are easy prey for hunters, who kill them for their hides and meat.

A Specialized Mouth

The most primitive snakes have heavy skulls and few teeth. Most snakes, however, have lighter skulls and jointed jawbones. These joints are loose and can easily become dislocated so that the snake can swallow prey larger than the natural shape of its own head. The teeth are fixed in the upper jaw or the palate, and the fangs for injecting venom may be located either at the front or at the back of the mouth. Some species, as well as being larged and powerful, have restractable fangs, allowing them to close their mouth when their fangs are not in use.

Cobras

Are an important group of snakes in the family Elapidate. Easily recognized by their outspread hoods, they are well known worldwide, mostly because of their use by snakes charmers. Many cobra species carry deadly venom. Some can even spit from several yards away. Cobras of the Naja genus are the most widely recognized. They are widespread in Asia and were only recently recognized as ten separate species. All are predatory; many eat only snakes.