About the cover

A 'Burgess Shale-type' fauna, rich in fossils of soft-bodied creatures, has been found in the Lower and Upper Fezouata formations of Morocco, dating from about 480-472 million years ago during the Early Ordovician. The Fezouata biota is a link between Burgess Shale communities of the Middle Cambrian and the Great Ordovician Biodiversification Event, previously represented mostly by 'shelly' fossils. The cover shows a marrellomorph arthropod from the Fezouata biota. Cover photo by P. Van Roy.