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Posts tagged “Mutualism

Ant Farmers

Certain species of ants have what is called a mutualistic relationship with aphids – a win-win situation for both the ants and the aphids. The ants protect the aphids from predators. In return, the aphids secrete droplets of “honeydew” from their abdomen when stroked by the ants’ antennae, which the ants devour. The act of stroking the aphids is referred to as “milking” them; hence, the ants are referred to as “farmers.”


Ants Farming Aphids

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Some species of ants “farm” aphids.  Ants and aphids have a mutualistic relationship, in which each benefits from the presence of the other.  The aphids feed off of the sap of plants, which is low in nutrients.  They must therefore consume a lot of sap in order to get adequate nutrition.  As a result, the aphids excrete large quantities of waste, called honeydew, which is high in sugar content.  This is where the ants come in – they love honeydew, and have actually learned to “milk” aphids by stroking them with their antennae, which stimulates the aphids to release honeydew.  In return for this delicacy, the ants protect the aphids from predators. Chemicals on the ants’ feet tranquilize and subdue the aphids, and even inhibit their wing development, keeping them close by as a ready source of food.  Ants have also been observed tearing the wings from aphids before they can become airborne.