Duck penises: http://scienceblogs.com/neurotopia/2010/01/friday_weird_science_duck_duck.php http://scienceblogs.com/neurotopia/2010/01/friday_weird_scie... I'm

Duck penises: http://scienceblogs.com/neurotopia/2010/01/friday_weird_science_duck_duck.php http://scienceblogs.com/neurotopia/2010/01/friday_weird_scie... I'm not kidding, either. Read the article -- it's pretty amazing how both male and female ducks have evolved to accommodate/discourage each other.