Abstract
It has been shown that kinship normally determines fertility in humans and animals. At smaller populations the curve of fertility against kinship rises steeply as kinship rises until inbreeding is reached. In large and progressively larger populations, fertility slowly falls. At an equilibrium point fertility matches replacement. Away from that, fertility changes by one of four published time courses. Earlier we demonstrated damped oscillation in a population of captive fruit flies. I hypothesized that since fertility changes so rapidly, DNA base mutations could not be the cause. The mechanism must be epigenetic, the control of genes, and gave varying doses of a methylating cocktail to the same flies. The fly population changed in a complex way, which only happens when there are pre-zygotic and post-zygotic processes in effect together.
One Sentence Summary There is evidence for an epigenetic effect – with both pre-zygotic and post-zygotic components – of kinship on fertility of flies (Drosophila melanogaster) induced by a methylating cocktail.
