Submission + - Scientists Discover Genitalia Arms Race in Ducks
GuyMannDude writes: From the you-go-girl department, Scientists are reporting that some female ducks and geese have evolved complex genitalia to thwart unwelcome mating attempts. The study details how vaginas of some duck species have evolved to feature complex structures designed to reduce the chances of forced impregnation. Male genitalia have evolved similarly to tip the odds in their favor, resulting in a sort of evolutionary "arms race" in which control over reproduction alternates between the sexes.