When wasps oviposit, they inject a quantity of virus and one or more eggs. Viral products then immunosupress the host. MdBV disrupts encapsulation by inducing apoptosis of one class of hemocytes and disrupting the ability of another hemocyte class to adhere to foreign surfaces. Previous comparative studies suggest that the developmental processes that regulate pattern formation in Drosophila well describe embryogenesis of advanced, holometabolous insects generally. There have been few attempts, however, to take into accout how life history has influenced early development of insects.
Studies are also underway to understand the development of polyembryonic insects.
Progress indicates that profound alterations in early development have arisen independently multiple times in the Hymenoptera. Several of these alterations have been essential preadaptations for the evolution of polyembrony. Male diploidy results in either sterility or lethality. This results in significant fitness costs and has selected for mechanisms in many haplo-diploid organisms to avoid inbreeding. Male diploidy is also of significant concern when using parasitoids in biological control.