Impressive, most impressive: Einmal Enten-Zeitlupen-Penis als GIF. Wer mehr über Genitalien von Federvieh wissen will, there you go:
Male ducks have elaborate corkscrew-shaped penises, the length of which correlates with the degree of forced copulation males impose on female ducks. Females are often unable to escape male coercion, but they have evolved vaginal morphology that makes it difficult for males to inseminate females close to the sites of fertilization and sperm storage. Males have counterclockwise spiraling penises, while females have clockwise spiraling vaginas and blind pockets that prevent full eversion of the male penis.