Resolving Mechanisms of Competitive Fertilization Success in Drosophila melanogaster

+ See all authors and affiliations

Science  16 Apr 2010:
Vol. 328, Issue 5976, pp. 354-357
DOI: 10.1126/science.1187096

You are currently viewing the abstract.

View Full Text


Our understanding of postcopulatory sexual selection has been constrained by an inability to discriminate competing sperm of different males, coupled with challenges of directly observing live sperm inside the female reproductive tract. Real-time and spatiotemporal analyses of sperm movement, storage, and use within female Drosophila melanogaster inseminated by two transgenic males with, respectively, green and red sperm heads allowed us to unambiguously discriminate among hypothesized mechanisms underlying sperm precedence, including physical displacement and incapacitation of “resident” sperm by second males, female ejection of sperm, and biased use of competing sperm for fertilization. We find that competitive male fertilization success derives from a multivariate process involving ejaculate-female and ejaculate-ejaculate interactions, as well as complex sperm behavior in vivo.

View Full Text