大象传媒

They have been doing it in Scotland longer than anywhere else - 385 million years in fact.

Scientists from Flinders University say sexual intercourse has been traced back to small ancient fish that lived there, called Microbrachius Dicki.

They are the first known creatures to stop reproducing by spawning and instead mate through intercourse.

Oxford University fossil expert, Dr Matt Friedman, said the fish may have developed the reproduction method to protect unborn young.

This clip is originally from Drive on October 20 2014.