Ants and their insect trap. Allomerus decemarticulatus ants inside a trap they have built on a Hirtella physophora plant. These South American ants cut hairs from the stem of this plant and bind the tiny fibres with a fungus to build a spongy snare (left) along the stem. They then wait inside the snare with their mandibles inside the holes. When an insect lands on the trap the ants grab any part of its body that protrudes into the holes and stretch the animal out flat across the stem. While restrained, other members of the colony paralyse it with their stings before dismembering it. The body parts are then carried back to the ants' nest to feed the colony. This technique is used to capture even the largest of insects, so long as some part of their body fits through the holes.