Unfamiliar with duck loving? Here are the basics: Corkscrewed vaginas and long, temporary, lymph-filled penises that uncoil in fractions of a second. Now researchers have found that some males' members grow longer when they're fiercely competing for a mate. The photo we have to illustrate this magnificent mating equipment is so graphic--in a duck kind of way--that we're putting it below the jump. As Carl Zimmer memorably put it when writing on the kinkiness of duck sex, it may not be "appropriate for ducklings."
Last week, Yale University's Patricia Brennan presented another finding on duck phalluses at a meeting of the Animal Behavior Society. When competing for females, it seems males of the scaup species try to out-size one another. Brennan found this after placing male scaups in two setups. In one, seven to eight males lived with five or six females, while in the other, drakes lived in more ...