A colony of Madagascar hissing cockroaches lives at our Children’s Animal Center. These invertebrates can reach three inches long and live up to five years in the wild. This species exhibits sexual dimorphism, as males have prominent protrusions on their thorax called pronotal humps. Females have very small bumps or none, plus a much smoother thorax. Males also have brushier antennae. Females appear to bear living young, but nymphs actually emerge from an egg case called ootheca. The ootheca is