Gustation and division of labor in ants

Jordan Smith

Ants have remarkably diverse diets that encompass live and dead invertebrates, extrafloral nectar, homopteran honeydew, seeds, fruits, and cultivated fungi. Their feeding ecology may involve complex division of labor. Despite their prevalence and ecosystem significance, research on ant gustation, or taste, is limited, with little integrative investigation into how diet and social organization affect the evolution of taste.  Moreover, the neurobiology of gustation in ants is not well understood.  

Fungus-growing ants are of particular interest because they are ultrasocial: they produce their own food crop and have full-time division of labor involving morphologically, behaviorally, and neurobiologically differentiated workers. These worker subcastes likely utilize gustation according to their social roles. While media workers, which are responsible for cutting and carrying back leaves and thus may require gustation to decide leaf quality, a minim worker that tends the fungal garden may instead use taste to cultivate their food crop.  

Focusing on the leafcutter ant Atta cephalotes, I investigate gustatory preferences and sensitivities, receptor types and distributions, and electrophysiological responses across worker castes. I am also interested in broader patterns of taste evolution across ant species, such as patterns of gustatory gene evolution across dietarily diverse species. At the intersection of social and sensory evolution, research can provide insight into the impact of division of labor on the evolution of taste.