Scientists recently identified the animal’s nerve cord by using a topsy-turvy twist. In 2012, after decades of studying Pikaia fossils, researchers described its fossilized internal structures in great detail. However, recent analysis of Pikaia fossils by another team of scientists, published June 11 in the journal Current Biology, has upended this view and all other earlier studies about Pikaia. The presumed blood vessel was a nerve cord, a feature associated with the animal group known as chordates, in the phylum Chordata. While there are no living analogues for Pikaia, the fossil arthropod data gave the scientists a more detailed frame of reference for Pikaia’s nerve cord.

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Persons: Charles Doolittle Wolcott, Giovanni Mussini, Pikaia, ”, Jon Mallatt, Mallatt, “ Pikaia’s, Jakob Vinther, Mussini, ” Mussini, we’ve, ” Mallatt, ” Mindy Weisberger Organizations: CNN, Smithsonian National Museum of, Royal Ontario Museum, University of Idaho, University of Bristol, University of Cambridge, Scientific Locations: Burgess, British Columbia, macroevolution, United Kingdom, mudskippers, chordates