Turn over a brick or a board that has been lying in the yard for a while and underneath you may find a collection of pill bugs scurrying about. Also known as "rollie pollies" or woodlice, these grey-colored creatures can be found in many dark, moist environments feeding on decaying matter. What's interesting about these critters is that they are not bugs at all. They are crustaceans and more closely resemble crabs and shrimp, not insects. They are characterized by their ability to roll up into a ball when they feel threatened. Another unique feature is that they have seven pairs of legs. They also act like kangaroos, toting their eggs around with them in a special pouch called a marsupium, located on the pillbug's underside. Even stranger, they don't urinate. Instead, they exchange gases through gill-like structures.
