Some people drink alcohol to drown their sorrows. So does the fruit fly Drosophila melanogaster, but its sorrows aren’t teary rejections or lost jobs. It drinks to kill wasps that have hatched inside its body, and would otherwise eat it alive. It uses alcohol as a cure for body-snatchers.

Insects the world over are plagued by parasitic wasps. The wasps lay eggs in or on the bodies of other insects, turning them into living larders for their developing grubs. The grubs eat their hosts from the inside-out and eventually burst out of their dead or dying husks. It’s a grisly fate, but D.melanogaster can do something about it.

Milan raised some fly larvae on food that contained 6 per cent alcohol,