Mary Jo DiLonardo has worked in print, online, and broadcast journalism for 25 years and covers nature, health, science, and animals. The roly-poly, or pill bug, is a terrestrial crustacean that ...

Pill bugs are gray pests related to crustaceans, and they are known for their ability to roll up into a ball when they encounter threats. Also commonly known as "roly-polies," these small ...