Ancient 'sharks' appeared much earlier than previously thought

Fanjingshania renovata. Credit: Heming Zhang - The first appearance of shark-like 'jawed fish' may have happened some 15 million years earlier than previously thought, according to new evidence. A handful of fossil teeth from a completely new species, uncovered from rock samples found in China, suggest jawed fish emerged some time at the end of the Ordovician, or beginning of the Silurian period, around 440 million years ago. Previously, the earliest jawed fish to be positively identified, included species from the upper Silurian era, 424 million years ago. These include the placoderms, a partially armoured species, and sarcopterygians, a bony 'lobe-finned' species found initially in China and Vietnam. The fossil samples were found and analysed by researchers at the University of Birmingham, in the UK, the Institute of Vertebrate Paleontology and Paleoanthropology, part of the Chinese Academy of Sciences and Qujing Normal University (QJNU), China. The results are published today [28 September 2022] in Nature.