American Cockroach

Yes, for about a week, and the reasons say a lot about how different an insect is from us. A cockroach does not breathe through its mouth or nose; air enters through small holes called spiracles along the sides of the body, each connected to its own set of air tubes, so removing the head does not stop respiration. Its nervous system is not centralised in a brain but distributed in clusters of nerve tissue down the body, which keep the legs and other functions working. And its circulatory system is open and low-pressure, so a clean wound to the neck seals rather than bleeding out. What eventually kills a headless cockroach is dehydration, because it has no mouth to drink with.

The name reflects where European naturalists first catalogued the insect in abundance, not where it evolved. Genetic and historical evidence indicates the species is native to tropical Africa and was spread across the world by shipping from the seventeenth century onward, moving in cargo, ballast, and provisions and establishing wherever the climate or heated buildings allowed. By the time it was formally described, it was a familiar pest in the Americas, and the label stuck. Several of the other large "domestic" cockroaches have similarly misleading names for the same reason, being tropical species distributed by trade.

They are usually the same insect under a gentler name. "Palmetto bug" is a term used in the southern United States, especially Florida and the Carolinas, for large cockroaches found around palmetto palms and in and near homes, and it most often refers to the American cockroach, sometimes to the smoky-brown or Florida woods cockroach. "Waterbug" is another euphemism for the same large roaches, borrowed loosely from the name of an unrelated group of true aquatic bugs. In each case the polite name is doing the work of making a cockroach sound less like a cockroach.

They do not bite in any meaningful way, they are not venomous, and they do not seek out people, but they are a genuine health nuisance rather than a harmless one. Because they feed and travel through sewers, drains, rubbish, and decaying matter and then walk across food, dishes, and surfaces, they can carry and deposit disease-causing bacteria. More significant for most households is allergy, because proteins in cockroach faeces, saliva, and shed exoskeletons are potent airborne allergens, and long-term exposure, particularly for children in infested housing, is a recognised cause of asthma and allergic disease. Controlling moisture, sealing entry points, and removing food and clutter are the main defences.