Meiotic drive in natural populations of Drosophila melanogaster 2. Genetic variation at the Segregation Distorter locus

It has now been found that the proportion of heterozygous SD males resulting from any given cross which exhibits segregation-distortion, and the amount of distortion that any particular male shows (the k value), varies widely depending upon the precise source and history of the SD-bearing and the SD+-bearing chromosomes in the heterozygotes being tested. It is the purpose of this report to present a general account of the kinds of variations in the behavior of SD which have been observed. More fully documented reports of each phase of the work are currently in preparation, and will be presented elsewhere. For this reason, extended discussion of these variations and comparable systems in other organisms has been omitted.