The Birth of Sex

Placoderms had intercourse “square-dance style” more than 385 million years ago.

Research in Nature details what may be the first acts of intercourse that took place some 385 million years ago in Scotland​. They performed the act in a maneuver the researchers called “square-dance style.”

Update, Nov. 28, 2016: This video has been removed pending the resolution of a licensing claim.