The Royal Ontario Museum has a new section on its web site devoted to the wonderful fossils of the Burgess Shale. These organisms date to the Cambrian period, not long after the explosion of multicellular life, when most of the modern phyla first appeared. Their age is estimated at 510 to 505 million years. The fossils are esquisitely preserved, including the soft parts of many organisms. The web site presents photographs of many fossils, along with reconstruction (drawings and videos) of what they may have looked like when alive. Above, fossil and reconstruction of the famous Anomalocaris canadensis.
Marrella splendens, a common arthropod.
Above, claw of Caryosyntrips serratus, of which only parts have been found.
Canadia spinosa, a swimming worm.
Habelia optata, an arthropod covered in tubercles.
Spicules of Choia ridleyi , a sponge.