The world was a very different place in the Cambrian time period, when animals of the Burgess Shale were thriving in tropical oceans. The Cambrian world map looked very different to that of today. The majority of land mass was located in the southern hemisphere and ancestral North America (Laurentia) was located near the equator and was a separate continent from the supercontinent (Gondwana). During the Cambrian, the Burgess Shale quarries lay just north of the equator, far offshore from the ancient coast of North America. Sediments deposited on the bottom of this ancient tropical ocean formed all the rocks that we see across the Kicking Horse, Emerald, and Yoho Valleys.
Map by Dr Christoper Scotese - Paleomap project
In the Cambrian, the Earth revolved faster, resulting in the days being 21 hours long and the year being 420 days long. The Moon was closer to Earth and consequently, tides were stronger. The Sun’s brightness was weaker than it is today, but a high concentration of carbon dioxide in the atmosphere compensated for the decreased solar energy to allow for temperatures to be acceptable for life.
The skies were empty of birds; there were no fish in the seas. There were no land lands, and without a protective covering, erosion rates were high.
Would you rather live in the Cambrian than present-day?
Revised for web format from “A Geoscience Guide to the Burgess Shale” by Murray Coppold and Wayne Powell, © The Burgess Shale Geoscience Foundation. To purchase this book, please go to: the Yoho National Park Visitors Centre, Alpine Book Peddlers, Amazon.ca, or Amazon.com