Scientists have unearthed the fossil and skull of an ancient fish that dates back to 415 million years in Siberia, and the fossil has features that are indicative of jawed vertebrates – including humans.
Known as the Janusiscus schultzei, the “bony fish” was unearthed in the 1970s, but researchers have now re-analyzed the fossil and discovered that it was a bony fish that had cartilage.
According to co-author Sam Giles of the Oxford University’s Department of Earth Sciences, “The results from our analysis help to turn this view on its head: the earliest jawed vertebrates would have looked somewhat more like bony fishes, at least externally, with large dermal plates covering their skulls.
“In fact, they would have had a mix of what are now viewed as cartilaginous- and bony fish-like features, supporting the idea that both groups became independently specialized later in their separate evolutionary histories.”
Most vertebrates usually have bony characteristics or cartilage – but this particular fish possessed both features and that is surprising enough.
“This 415 million year-old fossil gives us an intriguing glimpse of the ‘Age of Fishes’, when modern groups of vertebrates were really beginning to take off in an evolutionary sense,” said study co-author Matt Friedman, an Oxford Department of Earth Sciences colleague of Giles’.
“It tells us that the ancestral jawed vertebrate probably doesn’t fit into our existing categories. This mix of features, some reminiscent of bony fishes and others cartilaginous fishes, suggests that humans may have just as many features that you might call ‘primitive’ as sharks.”
This study was published in the journal Nature.