A primitive chordate from the Burgess Shale

More than 1/2 billion years old, the fossils of the Burgess Shale fauna preserve for us an intriguing glimpse of early animal life on Earth. These fossils are named after a Cambrian rock formation (the Burgess Shale) that is located in the western Canadian Rockies. They were first discovered there in 1909 by Charles D. Walcott, then Secretary of the Smithsonian Institution. Living among the variety of ancestral forms that make up the Burgess Shale Fauna is this earliest known representative of the phylum to which we ourselves belong. Averaging about 1 1/2 inches in length, Pikaia swam above the seafloor using its body and an expanded tail fin. Pikaia is not a technically considered a vertebrate - no you can say if this particular creature is our direct predecessor. Nevertheless, Pikaia is a representative member of the chordate group from which we undoubtedly arose. It resembles a living chordate commonly known as the lancet. Few Burgess Shale fossils are known in private collections and this museum quality cast is indeed just as rare.

The Burgess Shale is a fossil-bearing deposit exposed in the Canadian Rockies of British Columbia, Canada. It is famous for the exceptional preservation of the soft parts of its fossils. At 508 million years old (middle Cambrian), it is one of the earliest fossil beds containing soft-part imprints.

The rock unit is a black shale and crops out at a number of localities near the town of Field in Yoho National Park and the Kicking Horse Pass. Another outcrop is in Kootenay National Park 42 km to the south.