Hobbies And Interests
Types
There are approximately 8,500 species of known reptiles in the world, each belonging to one of four groups: Crocodilia (crocodiles and alligators), Squamata (lizards and snakes), Testudines (tortoises and turtles), and Sphenodontia (tuatara -- rare lizard-like animals). The most abundant reptiles are lizards and snakes. They exist in a variety of colors that include both dark and bright colors. Reptiles range in size from the dwarf gecko at approximately 120 milligrams to the saltwater crocodile that can weigh up to 2,200 pounds.
Environment
All reptiles are coldblooded, meaning that they obtain and regulate their body temperature from external origins such as the sun. This causes their internal body temperature to be approximately the same as the outside air. Most reptiles are found in warmer climates; however, they exist on every continent except Antarctica. Reptiles lie in the sun to stay warm and alert. If their bodies get too cold, reptiles can become lethargic and enter into a state of hibernation.
Breeding Habits
Nearly all reptile species lay eggs that are protected with a hard or leather-like shell. However, certain species of lizards and snakes give birth to live offspring. Female reptiles typically dig holes in the ground to lay their eggs in. Most mother reptiles will abandon the nest as soon as they have finished laying their eggs. However, some species of snakes and lizards will stay and guard the nest. Certain snake species will wrap their bodies around the eggs to keep them warm.
Extinction
The first known reptiles existed approximately 300 million years ago. The renowned dinosaurs are part of the reptile family and are now extinct. Corruption of habitat and food sources has led many reptile species to become extinct. Today, this loss of species is mainly the direct or indirect cause of human involvement. Human land development, hunting and introduction of predatory species have greatly reduced the chance of survival for many species of reptiles. For example, the Yunnan box turtle has been extinct since 1906 due to devastation of habitat. The Domed Rodrigues giant tortoise (Cylindraspis peltastes) became extinct in 1800 due to hunting and habitat destruction.