Scanning electron micrograph images of the nut (A,B)
and screw (C, D) in the leg joint of a Papuan weevil
What’s the News: Biologists spend lots of time poring over nature’s nuts and bolts. Now, for the first time, they’ve found a biological screw and nut—previously thought to be an exclusively human invention. The legs of beetles called Papuan weevils, researchers report today in Science, have a joint that screws together much like something you’d find in the hardware store.