UC San Diego

Purely parthenogenetic strains of Drosophila mercatorum were selected for by Dr. Alan Templeton in 1974 and have been kept in the UC San Diego Drosophila Species Stock Center for close to four decades. The distinct clonal reproduction of parthenogenesis in D. mercatorum is expected to negate sexual selection, select for superior asexual reproduction, and also allow neutral mutations. I investigated this hypothesis by studying the general reproductive biology of sexual and parthenogenetic D. mercatorum. This study showed that 38 years of purely parthenogenetic reproduction have significantly diverged these strains from the sexually reproducing strains in mating propensity, progeny production, sex ratio of the progeny, and virgin egg-laying. Such results suggest parthenogenesis to be an intense divergent force in evolution