Interactions between ageing and inbreeding effects on development of Drosophila melanogaster embryos.

Ageing and brother-sister inbreeding effects were studied simultaneously during the development of Drosophila melanogaster. Egg hatchability and adult emergence were investigated in relation to age of females laying the eggs and the age of the parents of these females. Each couple was followed individually. The effects of parental age varied according to the mating system used. Both hatchability and emergency of inbred eggs were affected by ageing. This indicates that parental constitution can influence early and later stages of development. Control of embryonic and larvo-pupal developments may involve processes perturbed by both ageing and inbreeding. Thus, information related to the genetic control system of development varies with the age of the flies and of their parents and consequently modulates the inbreeding effects. It is postulated that inbreeding and ageing may both involve cytoplasmic-genome interactions implicated in the control of embryogenesis.