Scientists say the first-ever animals to copulate were some small fish called Microbrachius dicki.
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Scientists 'discover the origin of sex'

Scientists say they have discovered the origin of copulation.

They say the first-ever animals to use this form of sexual reproduction were some small fish called Microbrachius dicki, who lived about 385 million years ago in Scotland.

This animation from the University of Flinders, in Australia, recreates how the animals took up a side-by-side position while mating.

The finding is published in the journal Nature.

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