Distribution of Micronutrients in Social Insects: A Test in the Termite <I>Reticulitermes flavipes</I> (Isoptera: Rhinotermitidae) and the Ant <I>Myrmica punctiventris</I> (Hymenoptera: Formicidae)

Abstract

Among social insects, individuals that grow or reproduce have different nutritional requirements than those that do not grow. Ants and termites have very different colony structure, and they should reveal differences in nutrient flow. Here, we show that the micronutrients calcium (Ca), copper (Cu), iron (Fe), potassium (K), magnesium (Mg), manganese (Mn), sodium (Na), and zinc (Zn) levels are different among castes in termite and ant colonies. In two separate experiments, colonies of the termite Reticulitermes flavipes (Kollar) (Isoptera: Rhinotermitidae) and the ant Myrmica punctiventris (Roger) (Hymenoptera: Formicidae) were divided into two equal-sized subunits. In both experiments, one subunit was fed an enriched diet containing Ca, Cu, Fe, K, Mg, Mn, Na, and Zn, whereas the other subunit was fed a control diet lacking these nutrients. In subunits fed the enriched diet, termite workers had higher levels of micronutrients than did soldiers, whereas ant workers had lower levels of micronutrients than did larvae. The only exceptions to this pattern were that Cu and Zn were found to be higher in termite soldiers, and Mn was found to be higher in ant workers. Our results suggest that micronutrients levels in both ants and termites match the nutritional requirements of different castes.