There are about 30,000 species in the scarab beetle family (Scarabaeidae), but the term 'scarab' is commonly used to describe one particular dung beetle with an interesting history.
The scarab collects a ball of dung and rolls it along to an underground burial chamber, where it crawls inside, feeds off the dung, and lays its eggs. When the eggs hatch, the larvae find themselves surrounded by food.
The ancient Egyptians, observing the adult going in and the young beetles coming out, believed that they had the power of regeneration. The beetle inspired their god Khepri, an enormous scarab who pushed the sun across the sky.
The ancient Romans adopted the myth and supposedly carried banners with a picture of the beetle into battle.