Bacteria Help Pitcher Plants Trap Prey

Pity the insect that tumbles into a pitcher plant's trap. The slippery walls and waiting pool of water ensure it won't clamber back out. There's nothing left to do but wait to be digested. The California pitcher plant (Darlingtonia californica) is also called the cobra lily for its curled-over shape that hides its exit from its victims. Unlike other pitcher plants, it doesn't fill its trap from above with rainwater but from below, drawing water up with its roots. But like others, it seems to use bacteria living in that well to help digest its prey. The bacteria perform another role too: making the liquid even harder for an insect to escape than ordinary water. Nearly a century ago, scientists first noticed that the water in the traps of some pitcher plant species had unusually low surface tension. This means an insect that's used to safely tiptoeing across puddles suddenly ...