In the Canadian Rockies lies one of the best ancient fossil sites in the world. The Burgess Shale is a gigantic rock formation made up of black shale. It dates back to a time when the planet would have been almost unrecognizable. The globe was dominated by several continents, all of which were concentrated around the Southern Hemisphere. If we could have viewed it from space we may have seen brown and bare rock devoid of any greenery. Plants had not yet made the odyssey onto land and so the world was dominated by marine beasts unlike any seen by human eyes.
The Burgess Shale is one of the most famous areas for preserving these strange creatures. The site was discovered in 1886 by Richard McConnell of the GSC, the Geological Survey of Canada. Since then, the GSC had been prospecting the area for the fossils of Cambrian life forms and soon a whole environment began to emerge. While many fossil hunters have combed the shale for a long time, it was Stephen Jay Gould’s 1989 book Wonderful Life that truly brought it to the forefront. On the whole this is a biota which marks the middle of the Cambrian Period, and the animals here are roughly 508 million years old. Most of the fossils were either misidentified or not named right away although any taxonomic messes were soon to be cleaned up. Subsequent studies of the rocks here also showed that there was a number of quarries all over the formation. These were explored at different times over the past century plus or so and every new quarry has revealed something extraordinary. The animals here were preserved via a process that has allowed even the soft tissues of the animals to remain as they were, as perfect imprints in the rock.
All of the animals here are products of the Cambrian Explosion. This event was a boom of life that occurred somewhat earlier during this era and gave rise to some of the strangest creatures that have ever lived. Most of them belonged to families doomed to die out while others managed to pull through. First of all, nothing at this time had a backbone. For many millions of years, invertebrates would be the dominant form of life on the planet and nowhere is it more obvious than here in the Burgess Shale.
The biggest animal, and also top predator of the Burgess Shale is Anomalocaris. Like many of the other creatures here, it was an arthropod. Today’s arthropods include insects, spiders, crabs, centipedes and almost anything else with jointed limbs and an exoskeleton. Cambrian arthropods though were far from being so standard and Anomalocaris was just one of these. Its name means ‘odd shrimp’ and this is a complete misnomer.
