cambrian

Of all the famous fossil localities in the world, perhaps none is as widely celebrated as British Columbia’s Burgess Shale. High in the Canadian Rockies, the Burgess Shale contains some of the oldest and most exquisitely detailed fossils of early life on Earth. Visiting the Burgess Shale requires some preparation — you must hire a guide and hike 22 kilometers at high elevation — but for a fossil enthusiast, the payoff is worth every step.

About 505 million years ago, the continent that would become North America straddled the equator. With no terrestrial plants or animals, the land was a barren landscape. The warm, shallow sea bordering the continent, however, hosted a carbonated reef teeming with a diverse array of organisms, most of which were relatively small bottom-dwellers. Periodically, the animals would get washed over the reef and deposited at its base, where their bodies accumulated in the muddy sediments. Today, these creatures are beautifully preserved in the Burgess Shale.