2012 Small World In Motion Competition

Sperm from two males competing within reproductive tract of a female fruit fly (Drosophila melanogaster)

Dr. Stefan Lüpold

Syracuse University
Department of Biology
Syracuse, New York, USA

Sperm of two different males (green and red) competing within the female reproductive tract of the fruit fly Drosophila melanogaster. Competition between sperm is a widespread phenomenon throughout the animal kingdom and a powerful evolutionary force driving species diversity. However, it has been nearly impossible to study the fundamental biological processes associated with such sperm competition, occurring whenever sperm from different males mix inside of females. The very recent development of genetically modified fruit flies that produce sperm with either green- or red-fluorescent heads (as seen in the movie) is now allowing us to answer important biological questions.