The gap was eight millimetres. The cockroach was taller than that, and it knew it, in whatever way a cockroach knows things. It lowered its head, swept its antennae across the underside of the shutter blocking the corridor, and shoved. The shutter lifted. The insect was through in a little under ten seconds, the same as any of its untouched cage-mates. The difference was that this one had a radio, a microproce New! Sign up for our email newsletter on Substack.