I think that turtles and snails have shells so they can protect there self from other animals.
add. The invention of the shell by snails and such was a major advance in evolution, for it provided a rigid part to which muscles could be attached. This provides superior locomotion. As above, this also provides protection from enemies.
The turtles are a different case, for these guys already have a skeleton to which muscles and articulation is attached. Their shell is a continuation of their body, not merely a separate case. So they may be considered to have both an exoskeleton and an endoskeleton.
Larger animals such as Rhino's and Hippo's also have very toughened skin almost forming an armour plate for protection.
A snake is a reptile. A snail is known as a mollusc.
it is a Amphibian... A frog is an amphibian, not a reptile.
A turtle is a reptile, not an amphibian.
A turtle is a reptile, not an amphibian.
A turtle is a reptile - NOT an amphibian.
A turtle is classified as a reptile, not an amphibian.
A turtle is considered a reptile, not an amphibian.
amphibian
amphibian
A salamander is a amphibian.
Reptile.
No. A snail is a mollusk.