Energy Allocation in Ephemeral Adult Insects

Abstract

Ephemeral adults must be structurally prepared to produce a certain number of progeny, because time of reproduction is not a maneuverable factor. Since structures are more visible than fecundity, reproductive strategies may be more easily studied and interpreted. A study of 10 species of parasitic wasps (Hymenoptera: Ichneumonidae), with ephemeral adults (longevity 13-31 days with only one or two generations per year), used ovariole numbers per ovary, egg volume and number, and the survivorship curve of the host, and host stage attacked, was used to interpret reproductive strategies. The balanced mortality hypothesis and Lack's hypothesis are supported. There is an evolutionary trend in the family Ichneumonidae for increased egg production paralleled by a decreased total reproductive effort