What Are Imaginal Disks in Ants?

What is eco-evo-devo? How can ants help us understand the evolution of development?

There are 20 quadrillion ants in the world, and they come in lots of different shapes and sizes. We even see big differences within colonies, like ants in the genus Pheidole which have different castes: workers, soldiers, and, in some species, super soldiers. Super soldiers are the muscle-y brutes of the ant world that grow huge heads to defend the colony and attack large food items, like other insects. This variation is all due to developmental plasticity – the same ant genotype produces distinct phenotypes depending on the environment of their early lives.

On this episode, we talk with Rajee Rajakumar, a professor at the University of Ottawa, who studies Pheidole ants to understand the interactions between their genes, their developmental environments, and their phenotypes. Rajee is also a HUGE ant fan! We talk with him about his 2018 paper in Nature about the mysterious organs that control these differences in development, and amazingly, how these organs could be socially regulated via pheromones.

Cover art: Keating Shahmehri