The African crested rat (Lophiomys imhausi) is hardly the continent's most fearsome-looking creature—the rabbit-sized rodent resembles a gray puffball crossed with a skunk—yet its fur is packed with a poison so lethal it can fell an elephant and just a few milligrams can kill a human. In a Journal of Mammology paper published today, the University of Utah, Smithsonian Conservation Biology Institute, and National Museums of Kenya researchers found the African crested rat is the only mammal known to sequester plant toxins for chemical defense and uncovered an unexpected social life—the rats appear to be monogamous and may even form small family units with their offspring.