Oocyte maturation and ovariole number in lines of Drosophila melanogaster selected for postponed senescence

1. Postponed senescence lines of Drosophila melanogaster have previously been generated by selection for delayed female reproduction. 2, This study addresses the question of whether the selection regime has differentiated lines with respect to oocyte maturation or ovariole number. 3. Oocyte stage and ovariole number were characterized in replicate postponed senescence lines (O) and in replicate control lines (B). 4. Oocyte maturation is delayed in O females. 5. The delay in oocyte maturation in O lines corresponds to reduced early age fecundity. 6. Selection may have resulted in an increased number of ovarioles in O females.