This is an asexual female adult pea aphid, Acyrthosiphon pisum, with first instar nymphs on fava. Pea aphids can be pink or green, a color difference that is genetically determined. The aphids shown here from the laboratory collection of Alex Wilson in the Department of Biology at the University of Miami are members of clone LSR1 whose genome was sequenced in 2010 by the International Aphid Genomics Consortium. Pea aphids feed on plant phloem sap, which is deficient in essential amino acids. Remarkably, the dietary shortfall of essential amino acid experienced by aphids is eliminated through their ancient collaboration with an intracellular bacterial symbiont, Buchnera aphidicola.