Why did the chicken cross the road? Maybe it was looking for its penis.

Warning: the following may be considered NSFW, particularly if your employer finds avian genitalia inappropriate.  Thanks to the detailed research of Patricia Brennan and the fluent coverage of it by Ed Yong and Carl Zimmer, a lot of people have not only heard of the impressive duck penis, they've seen it in all its explosive glory (if you don't know what I'm talking about, take a moment to click on the links above — trust me, it's worth it).