Aphid Tending- the parasitic-mutualistic train

A bizarre mutualism that you have to squint to observe - aphids are tiny insects that suck phloem (sugars that plants use for food) from a plant like sucking water from a coconut with a straw. They can be devastating to crops and gardens because they are such skillful phloem-stealers. Because of their constant sugar intake, aphid poop is carbon-rich and forms as a translucent bubble clinging to their rear (called honeydew). Aphid poop is so attractive to foraging ants that many species have gone the "extra mile" to secure this resource for their own colony.

Out at the Pot Holes in Eastern Washington, Formica sp. ants are especially adapt at aphid tending. Formica have an incredible defensive adaptation- spraying Formic acid at their enemies! They flip onto their back, lift their little butts and take aim at any threat. Formica nit-pick over their aphids like an overprotective mother- cleaning them with their antennae (research has shown this prevents fungal infections), defending them from predators (we tried poking at a cluster of aphids- and were sprayed with gas and bitten!) and, of course, transporting bubbles of honeydew back to the colony. Amazing!