For Ducks, Penis Length Depends On The Other Guys
New measurements find that the maximum length of a duck’s penis depends on the company he keeps. And in this case, it’s his fellow males who make the difference.
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The experiment shows that ducks “are essentially engineering their own phallus in response to social challenges.” Now she’d like to know more about just how this duck physiology works and whether any other species respond to sexual competition the same way.
Hmmm….?