When cars drive on a road with ponding water, a layer of water can form between the tires and the road. The car loses traction in a phenomenon known as aquaplaning. Drivers dislike aquaplaning because they lose control of their vehicle. Insects can also aquaplane in some situations. Insects use an array of spines, pads and other leg features for gripping surfaces. However, if a layer of water forms between the leg and the surface, the insect will aquaplane uncontrollably.
Pitcher plants in the genus Heliamphora live in nutrient poor soils. They attract insects and capture them in the liquid at the bottom of a pitcher-shaped leaf. The insects are digested and nutrients are available to the plant. The pitcher plant attracts naive insects with a nectar secretion. However, the inside surface of a pitcher leaf is super-hydrophilic.* This creates a film of liquid that coats the pads of insects such as ants. The insects find themselves aquaplaning down the sides of the pitcher leaf on a film of water where they are trapped and digested by the plant.
* ‘Insect aquaplaning’ on a superhydrophilic hairy surface: How Heliamphora nutans pitcher plants capture prey. Ulrike Bauer, Mathias Scharmann, Jeremy Skepper and Walter Federle. Proc. R. Soc. B 22 February 2013 vol. 280 no. 1753 20122569
Published online December 19, 2012 doi: 10.1098/rspb.2012.2569