Polymorphism in nature occurs when there are different shapes and sizes of individuals members within a single species.

Polymorphism in Ants

Many species of ant are polymorphic.  This means that a single egg laid by a queen ant will hatch into a larva that can develop into one of many different shapes of ant!  What kind of ant the larva develops into usually depends on the food that the larva is fed during development, and how the worker ants take care of it, and what other ants are present in the colony during the development of the larva.  For example, if there are many soldier ants present in the colony, the larva has less of a chance of developing into a soldier.  This is because pheromones produced by the many soldier ants will prevent the larva from developing into a soldier.