Significantly they were also the first vertebrates to develop copulatory behaviour for mating. They were the first to have three semicircular canals in the ear for improved balance. They were innovators – the first creatures to evolve jaws, teeth and paired hind limbs (pelvic fins). Yet placoderms were truly pivotal to our distant deep evolution. This new discovery shows beyond doubt that an extinct group called “placoderms” were actually the ones that gave rise to all modern fishes.ĭespite dominating the seas, lake and rivers of the world for more than 70 million years, almost no-one today would know the difference between a placoderm and a pachyderm. Living jawed fishes fall into two major groups: sharks, rays and chimaerids ( chondrichthyans) and true bony fishes ( osteichthyans). So what is this hypothesis he refers to? For decades there has been heated debate among scientists as to which early back-boned fishes were ancestral to modern fishes. But the fossils provide evidence to force us to have a reconsideration on the hypothesis. Wow, it is beyond our wildest expectation if we stick to the available phylogenetic scenario. Lead author on the study, Zhu Min of the Institute of Vertebrate Palaeontology and Palaeoanthropology in Beijing, said when I spoke to him: This is arguably one of the most exciting fossil discoveries in the past century since Archaeopteryx, the first fossil to bridge the gap between dinosaurs and birds.
For palaeontologists this fish is as big as finding the Higgs-Boson particle because of its immense significance to our understanding of early vertebrate evolution. The 419 million year old armoured fish, called Entelognathus, meaning “complete jaw” solves an age-old debate in science. Brian ChooĪ spectacular new “missing link” fossil has been unearthed in China. Finding Entelognathus is a revelation comparable to the discovery of Archaeopteryx.
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