Selective Resorption of Aphid Embryos and Habitat Changes Relative to Life-Span

(1) Adult Megoura viciae, starved for 5 days, resorb their smallest embryos while continuing to mature the largest embryo in each ovariole. (2) This response to starvation is very different from that of other insect species, in which it is the largest, or 'basal' oocyte in an ovariole that is resorbed. This dichotomy is explained in terms of the probability that conditions will improve dramatically during an adult insect's life-span. (3) An aphid invests less in the smallest of its basal embryos than in the larger ones, whose relative growth rates are consequently higher.