Snails have shells the moment they're born, but it's kind of hard to tell. In fact, it's hard to even see a baby snail. Some are nearly microscopic, such as Angustopila psammion, whose adult-sized ...

Snail shells are often colorful and strikingly patterned. This is due to pigments that are produced in special cells of the snail and stored in the shell in varying concentrations. Fossil shells, on ...