Tortoises or land turtles are land-dwelling reptiles of the family of Testudinidae, order Testudines. Like their marine cousins, the sea turtles, tortoises are shielded from predators by a shell. The top part of the shell is the carapace, the underside is the plastron, and the two are connected by the bridge. The tortoise has both an endoskeleton and an exoskeleton. Tortoises can vary in size from a few centimetres to two meters. Tortoises tend to be diurnal animals with tendencies to be crepuscular depending on the ambient temperatures. They are generally reclusive and shy.
Tortoises as pets
Many tortoises, (for example, the red-footed), have specific temperature, roaming space, light, air moisture, and diet requirements. They are difficult to captive breed, so many are wild caught. Tortoises need outdoor space to roam. It is not possible to house-train a tortoise.
Diet
Most land based tortoises are herbivores, feeding on grazing grasses, weeds, leafy greens, flowers, and certain fruits. Their main diet consists of alfalfa, clover, dandelions, and leafy weeds, although they will also eat various insects. Feeding tortoises cat or dog food is a common mistake, as both cat and dog food contain too much protein and lack other important nutrients for tortoises. Tortoises are not carnivores, and should not be fed large amounts of protein, as it may cause shell deformation and other medical problems.
There is a large amount of speculation on the use of tortoise pellets when feeding tortoises as in fact, tortoise pellets contain way too much protein, which will cause shell deformation and other medical problems. As a general rule, tortoises kept as domestic pets (usually Testudo Graecae and Testudo Hermanae) should be fed on weeds such as dandelions and clover and that is all that is needed. Calcium Carbonate can be ground into powder and added with weeds to provide extra essential calcium to a tortoise's diet.