Sperm pairing is unique to the opossum the Didelphids of South America. This phenomenon does not occur in Australian marsupial or other mammals.


**You may need to download QuickTime, a free program from Apple to view this video. At the Apple page click the tab that says QuickTime.

 

Swimming Paired Opossum Sperm

Scanning Electron Micrograph (SEM) of paired opossum sperm.