Answer to earthworm's ability to digest poisons unearthed by scientists

All plants contain toxins which continue to work after leaf fall, so how worms are able to stomach dead grass and leaf litter has long been a mystery

British scientists have cracked the global earthworm mystery: they have worked out how the planet's great subterranean reprocessing system copes with the poisons that would choke most herbivores.

Earthworms underwrite almost all life on earth: they drag fallen leaves below the soil and digest them, to excrete that rich mix of loam and living things called topsoil. Every year, 35 billion tons of dead grass and leaf litter get turned over by the worms and other soil fauna. But the catch is that some plants are really poisonous, and all plants contain some toxins designed by evolution to discourage demolition by herbivores, and these toxins carry on working even after leaf fall.