Reptiles are cold blooded animals, covered with scales, and mostly lay eggs. Some reptiles eat plants, some eat animals and some eat both. Reptiles are tetrapod vertebrates, meaning they have four limbs or, like snakes, they descended from four limbed ancestors. They usually have limited means of maintaining a constant body temperature and rely on external sources of heat. Being cold blooded requires far less fuel to function. A crocodile needs a fraction of the food a lion of the same weight needs, and can live half a year without eating. Due to their slow metabolism, reptiles can do well in areas where food sources are too low for most mammals and birds to live.


Snakes are long and legless carnivorous reptiles of the suborder Serpentes. Unlike legless lizards, they do not have eyelids and external ears. Snakes are vertebrates covered in overlapping scales, many with skulls that have several more joints than lizards allowing them to swallow much larger prey than the size of their heads. Because of their narrow bodies, their paired organs are lined up one in front of the other instead of side by side. Snakes live on every continent except Antarctica. Their are about 3,400 known species of snakes. Different species vary in size from the tiny thread snake, only 10 cm long, to the giant reticulated python growing to over 20 feet long.


Copperheads are a species of venomous snake in North America, a member of the Crotalinae (pit viper) subfamily. Five subspecies are currently recognized. They get their name from the unique copper hue present on the scales of their heads. Copperheads grow to an average length of 20–37 inches (including tail). They have unmarked copper-colored heads, reddish-brown coppery bodies and chestnut brown crossbands that constrict towards their midline. Their thick bodies feature keeled scales. Males are usually larger than females, though females grow to greater lengths.


The most common snake of the Anaconda genus is the green anaconda. These snakes are found in the tropical forests of South America and have the scientific name, Eunectes murinus. All members of the Eunectes genus are aquatic and found in South America; namely Ecuador, Peru, Bolivia, Brazil, Columbia Venezuela and Trinidad & Tobago. The green anaconda is considered the largest snake in the world. Its cousin, the reticulated python, rivals the anaconda in length, but the anaconda’s girth makes it nearly twice as heavy.


Members of one of the most diverse groups of lizards, skinks are reptiles with cylindrical, streamlined bodies, functioning eyelids and tight, smooth, scaly skin. They belong to the family Scincidae, and their name comes from the Greek word skinkos, which was a name that was used to refer to lizards in a specific region of the country. Over 1500 distinct species of skinks have been described, living in a wide range of habitats worldwide, from dry deserts, to mountains, grasslands and forests.


Rattlesnakes are a group of venomous (poisonous) snakes that live in a wide range of habitats, and have the scientific name Crotalus cerastes. There are 32 known species of rattlesnakes, and they can be found all over the Americas, ranging from Alberta and British Columbia, Canada, to as far south as Argentina. These fascinating snakes get their name from the rattle at the end of their tails – when the snake shakes the rattle, it makes a loud noise that helps to defend the snake by warning off predators or passing larger animals. It’s basically the snake’s way of saying ‘watch your step!’


The green or common iguana is a species of large, docile lizards native to the tree tops of Central American, South American and Caribbean rainforests. They are omnivorous reptiles bearing the scientific name Iguana iguana. One of the largest lizards in the Americas, they measure from three to six and a half feet in length and weigh in at eight to seventeen pounds. Other members of the iguana family include the Fiji Island banded iguana, the Galapagos Island marine iguana and the desert iguana. These lizards vary in size, appearance and endangered status.


True old world lizards with evolutionary roots that date back as far as 61 million years ago; chameleons are some of the most unique reptiles on earth. There are around 180 different species of chameleon belonging to the family Chamaeleonidae, which can come in a myriad and dazzling range of colors and sizes. Many species have the astounding ability to change colors in order to blend into their environment. Naturally preferring warm climates, chameleons live in habitats that range from rainforest to dry desert, and chameleons have been found to occur, depending on species, in Africa, Madagascar, Europe, and southern Asia (as far as Sri Lanka).


All sea turtles are protected by the Endangered Species Act, which lists all species as endangered except the loggerhead, which is listed as threatened. Marine turtles are one of the earth's most ancient creatures, with a fossil record going back 150 million years. Some estimates suggest they first appeared on earth as much as 230 million years ago, making them 224 million years older than humans. There are seven species of sea turtles.


Komodo dragons are monitors, any of various dragonlike, mostly tropical lizards. A monitor lizard has a heavy body, long head and neck, long tail that comes to a whiplike end, and strong legs with sharp claws. Its slender, forked tongue is protrusible. Monitors range in size from the 8 inch short-tailed species of West Australia to 10 feet, 300 lb. Some monitor species spend their lives in trees, and others inhabit lakes and rivers; they can be found on the oceanic islands and continents of the Eastern Hemisphere in all types of warm habitats, from tropical forest to desert. Komodo dragons, the giant among living lizards, live on the small Indonesian island of Komodo.


Crocodiles are large, carnivorous reptiles of the order Crocodilia, found in tropical and subtropical regions. Crocodiles live in swamps or on river banks and catch their prey in the water. They have flattened bodies and tails, short legs, and powerful jaws. The eyes, ears, and nostrils are located near the top of the head and are exposed when the crocodile floats on the surface of the water. The ears and nostrils have valves that close when the animal is submerged. Most crocodiles are more aggressive than the related alligators.


An alligator is a crocodilian in the genus Alligator of the family Alligatoridae. There are two living alligator species: the American Alligator (Alligator mississippiensis) and the Chinese Alligator (Alligator sinensis). They are closely related to crocodiles. Alligators are characterized by a broader snout and eyes more dorsally located than their crocodile cousins. Both living species also tend to be darker in color, often nearly black (although the Chinese alligator has some light patterning.) Also, in alligators only the upper teeth can be seen with the jaws closed (in contrast to true crocodiles, in which upper and lower teeth can be seen).


Python is the common name for a group of non-venomous constricting snakes, specifically the family Pythonidae. Other sources consider this group a subfamily of the Boas (Pythoninae). Pythons are more related to boas than to any other snake-family. There is also a genus within Pythonidae which carries the name Python (Daudin, 1803). Pythons are distinguishable from boas in that they have teeth on the premaxilla, a small bone at the very front and center of the upper jaw. Most boas produce live young, while pythons produce eggs. Some species of sandboas (Ericinae) are also called python.


Turtles are reptiles of the order Testudines characterized by a special bony or cartilaginous shell developed from their ribs that acts as a shield. "Turtle" may refer to terrapins, tortoises or sea turtles. The earliest known turtles date from 215 million years ago, making turtles one of the oldest reptile groups and a more ancient group than lizards, snakes and crocodiles. Of the many species alive today, several are highly endangered. Like other reptiles, turtles are ectotherms - their internal temperature varies according to the ambient environment, commonly called cold-blooded. Like other amniotes (reptiles, dinosaurs, birds, and mammals), they breathe air and do not lay eggs underwater, although many species live in or around water.