Fecundity Decrease in Drosophila simulans in the absence of Wolbachia

By: Jack Taylor, Biochemistry and Molecular Biology ’15

Sponsor: Michael Turelli, Ph.D.

Ecology and Evolution

Many species of arthropods host Wolbachia, maternally transmitted bacteria that often influence host reproduction. This manipulation of host reproduction has contributed to Wolbachia becoming a normally-present infection of many Drosophila simulans. The Y36 isofemale line, a population of Drosophila simulans created from a single female collected in 2010 in Yolo County, produces flies which have an unusual phenotype when reciprocally crossed with uninfected simulans populations denoted U. The cross between Y36 male and U female produces female offspring with significantly lower fecundity than the reciprocal cross (Y36 female with U male). It is possible that this effect is a result of a paternal defect gene that is masked by the Wolbachia infection. Ten separate sublines were created from the Y36 isofemale line. The goal of my experiment was to determine whether this phenotype is still present among each of the ten sublines and if there is any variation in the phenotype among the sublines. Analysis of the data indicates that the qualitative effect of the phenotype has been preserved across the sublines but suggests that there is quantitative variation amongst them.