When Did The First Reptiles Appear?
Reptiles are a group of vertebrate animals which, today, include snakes, turtles, lizards and crocodiles. Reptiles first appeared during the time period known as the Carboniferous (326 to 299 million years ago).
Distinguishing Reptiles From Their Ancestors
Reptiles can be distinguished from their earlier ancestors by their more advanced breathing systems. Only the amniotes (a group of animals with tough protective shells, such as reptiles and birds) had the ability to lay eggs on land and not in water. Unlike amphibians, reptiles could thrive on land without having to go back to the water constantly, allowing them to spread and colonize much of the world.
Important Adaptations of Reptiles
Reptiles have several important adaptations that have allowed them to survive and grow as a species. These include:
- Amniotic Eggs: Amniotic eggs are hard shells that protect and store the embryo, allowing it to survive on land without the need for ponds or water to keep them humid.
- Dorsal Nerves: Reptiles are also distinguished by their dorsal nerves, which provide them with reflexes, motor control and sensory organs in the brain.
- Thickened Skin: Reptiles also have thickened skin more suited for terrestrial environments, which includes protection from sunlight and dehydration.
Reptiles were one of the most successful groups that evolved during the Carboniferous Period. Their adaptations gave them the ability to survive and colonize much of the world. Today, reptiles are a diverse and abundant group of animals, making them an important part of our ecosystem.