Reptiles have diverse ways of defending themselves from danger including biting, hissing, camouflaging, and avoidance. This article focuses on some of the most outstanding characteristics of reptiles. Most reptiles reproduce sexually while others are capable of reproducing asexually. The reproduction activities take place through the cloaca located at the base of the tail.
Copulatory organs can be seen in most reptiles which are often stored inside their bodies. Male turtles and crocodiles have a penis while lizards and snakes have a pair of hemipenes. Other species like the tuatara do not have copulatory organs hence mating is through the pressing together of the cloaca. After successful copulation, the female reptile lays eggs which are covered with a shell. The eggshell protects and keeps the embryo from drying out and allows for the exchange of gasses.
The egg contains chorion which aids in gaseous exchange, the albumen which is a reservoir for protein and water, and the amniotic fluid which protects embryo and aids in osmoregulation. Some reptiles incubate the eggs by laying on them while others bury them in the sand until they hatch.
Most reptiles are cold-blooded vertebrates. They do not have the psychological means of regulating their body temperatures and have to depend on the external environment. Other species exhibit a mix of ectothermy, poikilothermy, and brandymetabolism. Reptiles often bask in the sun or hibernate during cold seasons to raise their body temperatures. When the sun is too hot, they will retreat to shady areas or inside the water to cool or lower their body temperatures.
Because reptiles have unstable body temperature, their metabolism requires enzymes that are capable of maintaining efficiency over a range of temperatures. It is assumed that reptiles cannot produce enough energy required for long-distance chase like the warm-blooded animals. However, it remains unclear as to whether their cold-bloodedness is as a result of their ecology or not. Reptiles have either four legs, or some like snakes, are descendants of four-limbed ancestors. When the young hatch, they are fully formed and ready to begin life on their own.
With the exception of a few types of reptiles, like crocodiles and some snakes who guard the nest, the parents do not tend to the young at all. The female lays a nest and then leaves.
A few kinds of reptiles, however, bear live young. Since reptiles don't use internal energy to keep their body warm, they don't need nearly as much food as mammals. On average, they eat 30 to 50 times less than warm-blooded animals and birds. Most reptiles are carnivores, and eat small insects or other animals, but a few are herbivores and only eat plants. Reptiles are divided into four basic groups: snakes and lizards, of which there are about 8, species; crocodiles and alligators, which include approximately 25 species; turtles and tortoises, which include over species; and two known species of tuatara.
By using the site, you agree to the uses of cookies and other technology as outlined in our Policy, and to our Terms of Use. Body Temperature Reptiles use sun and shade to regulate their internal body temperature, since they are ectothermic, or cold-blooded.
Skin Unlike amphibians, who have moist, slimy skin, reptiles have dry, scaly skin. Most reptiles can live their entire lives on land and reproduce in dry habitats. Some types of reptiles such as sea turtles and penguins are adapted to living in water, but even these species come onto land to lay their eggs.
All reptiles also have lungs, so even those living in water must come to the surface to breath air. Reptiles are found living in all habitats but are more common in warm, tropical places.
So, why are birds considered reptiles? Birds look very different from other reptiles, they have feathers, fly, sing complex songs, and have many other unique features. Animal groupings are most useful when they reflect the evolutionary history of the animals in that group. So, for example, "mammals" is the name of a group of animals that are all more closely related to each other than to other kinds of animals.
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