Info about Reptiles
Reptiles – An Overview of History and Characteristics
Class Reptilian’s history can be traced back to 300 million years ago. They are among the species with the longest lives. Having evolved from amphibians during the Carboniferous Period, they were able to adapt to the warmer climate by migrating inland and starting to produce eggs with membranes, better known as amnions. Their eggs had harder shells to adapt to the new environment.
The first reptiles lived in rivalry with amphibians. Nature seemed to have sided with the reptiles that even catastrophes for other species appeared to have favored them. The largest reptiles – the dinosaurs, reigned when the Mesozoic Era began. Nevertheless, these powerful creatures eventually became extinct. After a series of evolutionary adaptations, modern members of this class finally came to being.
• Modern reptilian species
There are currently more than 8,000 reptile species. They can survive anywhere in the world except in Antarctica. Snakes and lizards are the most numerous species of this class. All of them are cold-blooded but this term is not widely accepted. The more widely accepted scientific label is “ectothermic”. This term refers to the fact that these animals' body temperature changes with the temperature of their surroundings because they cannot regulate their own body temperature.
They have bodies covered with dry, horny water-proof scales. These scales protect them from abrasion and loss of body moisture and consist of a durable proteinaceous substance called keratin. They shed their scales from time to time to get rid of their old skin and parasites. This process, which is sometimes referred to as “molting” also allows growth. A common misconception is that reptiles are slimy but they really are not. This is because they lack sweat glands.
• Reproduction
Most reptiles reproduce sexually, although some of them reproduce asexually. Most lay hard-shelled eggs but some give birth to live babies. The hard-shelled egg or amniotic egg allows air in and is resistant to water. This allows the laying of eggs in moist environments which many reptiles prefer. This also helps in the development of the embryo since water is needed for hydration and for metabolic processes.
• Respiration, Circulation and Senses
Majority of the reptiles have three-chambered hearts with the exception of crocodiles and alligators, which have four-chambered hearts like mammals. Every reptile breathes through its lungs. In terms of sensing, they do not smell through their noses but instead with their tongue. They flick their tongues to accumulate the scent particles. By using this ability, they are able to hunt their prey and evade their predators.
• Eating Habits
They are predominantly carnivores. They do not chew their food. Instead they just tear it apart. This method of eating extends their digestion process. Huge reptiles can eat a single big meal and live without eating anything afterwards for a month. There has been news about boa constrictors swallowing whole people and hibernating afterwards in order for them to digest their meal. Turtles are the only ones which are herbivores in this class. They lack complex teeth and compensate by swallowing pebbles to support the digestive process.
Reptiles are interesting. They can live in the wild but many can also live as pets. They should be protected from extinction.