CHICAGO — Like the cockroach babies that hatched this week at Peggy Notebaert Nature Museum, the little offspring that could be in your house are white — at least for a few hours.
Allen Lawrance, Notebaert's invertebrate specialist, said all cockroaches are white when they hatch because their cuticle is still soft. Within a few hours, the cuticle will undergo a process called tanning, which "makes it harden by cross-linking chitin in the exoskeleton," Lawrance said.
"There are no albino cockroaches, so if you see one, wait a few hours, and it will turn dark," Lawrance said.
The cockroaches that hatched at Notebaert this week are Madagascar hissing cockroaches and not native to Illinois. According to National Geographic, the hissing roaches can live five years in the wild and reach 3 inches in length. They hiss by exhaling air through breathing holes, and the hissing is used in mating and as an alarm cry.
"Their large size and docile nature make them great organisms for close observation in the classroom," Lawrance said.
While the hissing roaches carry their egg cases — called oothecae — with them until they hatch, common pest roaches deposit their oothecae before they hatch, Lawrance said.