Reptiles (Class Reptilia) are cold-blooded vertebrates that diverged from ancestral amphibians about 340 million years ago. There are two characteristics that distinguished early reptiles from amphibians and enabled them to colonize terrestrial habitats more extensively than their ancestors: scales and the ability to lay hard-shelled amniotic eggs. Scales protect reptiles from abrasion and loss of body moisture. Hard-shelled eggs provide a protective environment in which the embryo can develop.
There are nearly 8000 species of reptiles, found on every continent except for Antarctica. The fact they are cold-blooded (also known as ectothermic) means they are incapable of maintaining a consistent body temperature on their own. They rely on the things around them to warm up or cool down. Their ability to move warm blood into the body core allows them to conserve energy. Today, scientists classify reptiles into four major groups known as "orders."
These four reptile orders are as follows:
In the Clyde area, 3 native species of Reptiles are found:
Life History The ony snake found naturally within the Clyde catchment, the adder (Vipera berus) is also the only venomous snake in Britain. More likely to flee before you get close to them, adders pose little risk to people. What do they look like? The adder is Britain’s only venomous snake. Adders...
Life History The most common reptile encountered within the Clyde catchment, the common or viviparous lizard (Zootoca vivipara) are found in a huge variety of habitats within the area. What do they look like? Adult Common lizard measure approximately 15 cm. They have long bodies and short...
Life History Actually legless lizards, most people who think they have seen a slow worm (Anguis fragilis) are mistaken. Preferring to live in udnerground burrows, slow worms are a cryptic secies that is not frequently encountered. They may be more common than we realise. What do they look...
Emma Downie, CARG Secretary