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Hallucigenia: The worm with the missing head

The remains of an ancient worm species called Hallucigenia were so bizarre looking that scientists originally reconstructed it upside down and back to front. Now Martin Smith reveals the most complete picture so far of this peculiar marine worm.

Read the Nature paper 'Hallucigenia's head and the pharyngeal armature of early ecdysozoans' at

Find out more about Hallucigenia and other finds from the Burgess Shale at

24 June 2015