It’s a rainy day in the jungles of Borneo, and an ant has taken shelter from the falling drops by clinging to the underside of a leaf. It has chosen poorly. Its shelter is the ‘lid’ of a pitcher plant, and it hangs over a living vase full of digestive fluids. As rain pummels the jungle, a drop lands on the lid and flicks off the ant underneath. The insect falls into the pool of fluid and is consumed by the plant.
Pitcher plants are famous for their flesh-eating ways, and they rely on slippery surfaces to trap their prey. Its pitcher-shaped traps are made from rolled up leaves, and secrete nectar from their rims to entice their prey. During wet conditions, the rims are coated with a thin layer of water, making them extremely slippery. They have another trick too – tapering wax crystals on the inner walls of the pitcher. These greatly reduce the surface area that insect feet would cling to, and ensure that individuals that fall inside can’t climb back out.