This article was originally published on The Conversation.
It looked more like the worm on an angler’s hook than any living fish we might recognize today but it still takes the record for the oldest known fish to date.
The first fossil fishes are known from scant and often ambiguous fossil remains, and research published today in Nature gives us the first clear picture of exactly what these earliest fishes were really like.
The 518 million-year-old fish Metaspriggina walcotti was about 2 inches long, bore a pair of large protruding eyes and small paired nasal capsules. It breathed through seven pairs of external gills. It had a stout rod supporting its spine (notochord) enabling strong W-shaped muscle bands to develop along its entire body.
