Info about the first jaw
Sep. 30th, 2013 10:12 amThe ancestor of all creatures with jaws and a backbone was not a sleek, shark-like beast but a toothless, armoured fish, say researchers, in a finding that rewrites human evolutionary history.
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The researchers report their discovery of a 419-million-year-old fish fossil in China, which they say disproves the long-held theory that modern animals with bony skeletons (osteichthyans) evolved from a shark-like creature with a frame made of cartilage.
http://www.abc.net.au/science/articles/2013/09/26/3856025.htm