Biochemical Ecology of Canavanine-Eating Seed Predators

Abstract

L-canavanine, a nonprotein amino acid structurally similar to L-arginine, is potentially toxic to many insects. In northwestern Guanacaste Province in Costa Rica, most insect seed predators do not feed on seeds that contain canavanine. However, several larval Coleoptera have become specialists on canavanine-containing seeds. Three of these beetles were compared with a number of other insects with regard to their biochemical ability to deal with and utilize L-canavanine. Our analyses revealed that certain biochemical capacities required by canavanine-feeding insects may have existed prior to their exposure to dietary canavanine. Key words: at~r:inase;