Sexual intercourse was pioneered by a group of fish about 385 million years ago

Scientists studying fossils have discovered that the intimate act of sexual intercourse used by humans was pioneered by ancient armoured fish, called placoderms, about 385 million years ago in Scotland. The scientists found that male fossils of the Microbrachius dicki, which belong to a placoderm group, developed bony L-shaped genital limbs called claspers to transfer sperm to females. Females, for their part, developed small paired bones to lock the male organs in place for mating.

We’ve solved this great mystery. They [bony paired arms] were there for mating, so that the male could position his claspers into the female genital area.

John Long, a palaeontologist at Flinders University in South Australia

Placoderms are the earliest vertebrate ancestors of humans. John Long, a palaeontologist at Flinders University in South Australia, whose study was published in the journal Nature on Sunday, discovered the ancient fishes’ mating abilities when he stumbled across a single fossil bone in the collections of the University of Technology in Tallinn, Estonia, last year. In one of the more bizarre findings of the study, Long said the fishes probably copulated from a sideways position with their bony jointed arms locked together—making them look more as if they were square dancing than having sex.

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