Sex is intriguing in all its forms, and bird sex is particularly intriguing. Some male birds have giant corkscrew-shaped penises, but most have none, thanks to its evolutionary disappearance millions of years ago. For “Matter,” my weekly New York Times column, I take a look at the case of the disappearing penis, and why it’s important to study, despite what some cable news pundits may say.
(And for you anatomy junkies, Ed Yong has more!)
Originally published June 6, 2013. Copyright 2013 Carl Zimmer.