The face of the predatory fish shown above is around 419 million years old and it's the earliest known example of a fish to possess the facial bone structure we recognise today.
The beautifully preserved 20cm/8" fossil of Entelognathus primordialis was discovered in a quarry in China. The fish has a jaw, a mouth, a nose and a pair of eyes.
The fossil has scientists really excited because it has characteristics of placoderms (ancient shark-like creatures which were heavily armoured) in the body and the top of the skull, but the pattern of bones in the jaws is almost identical to that of modern bone-bearing vertebrates including most fishes and all tetrapods — including humans.
It had previously been assumed that placoderms became extinct and bony fishes evolved later, independently developing facial bones and the modern jaw. But this fossil could mean that placoderms didn't die out but instead evolved into the bony fish which ultimately gave rise to land vertebrates such as mammals — and humans. So the face shown above could belong to one of your ancestors!
The study by Min Zhu of the Chinese Academy of Sciences' Institute of Vertebrate Paleontology and Paleoanthropology in Beijing and his colleagues is published in the journal Nature.
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