Sociobiology of Terrestrial Isopods

Abstract

Isopods are the only crustacean taxon with many truly terrestrial species, including desert inhabitants. These species show a highly developed social behavior that is crucial for survival under the harsh conditions in desert environments. The desert-living Hemilepistus spp. depend on burrows that are costly to produce, can only be dug anew in spring, and have to be continuously defended against competitors. This is achieved by division of labor between the sexually and socially monogamous pair partners, and later with the progeny's participation. Using a comparative approach, this chapter draws inferences about the probable evolutionary route to the strict monogamous mating system found in one of the best studied and highly social species, H. reaumuri. It concludes that the narrow temporal window during which the extremely valuable family burrow can be constructed has resulted in the sophisticated social behavior found in this semelparous oniscoid isopod.