A shell is a hard, rigid outer layer, which has evolved in a very wide variety of different animals, including mollusks, sea urchins, crustaceans, turtles and tortoises, armadillos, etc. Scientific ...

A group of fishermen discovered an animal shell belonging to a prehistoric armadillo on a riverbank in Argentina, according to reports. Imanol Ojeda said he spotted the mostly intact shell—which is ...