Produced by the Population Genetics and Evolution class, Furman University
The Cambrian: The Burgess Shale Formation
| The Burgess
Shale Formation was discovered in 1909 by Charles D. Walcott while exploring
for the Smithsonian Institution (Scott et al. 2000). It is located in
the Burgess Pass in the Canadian Rockies and named after the nearby Mount
Burgess. The Burgess Shale Formation is one of the most important fossil
formations ever discovered, as it contains very detailed traces of soft-bodied
animals from the Cambrian era (Encyclopaedia Britannica 2010). These animals
lived in a warm, shallow sea near a carbonate reef when a mudslide caused
them to be swept off the reef where they were buried and instantly killed
in an environment completely devoid of oxygen. It is believed that clay-particles
were forced into the animals’ cracks and crevices, protecting them
from scavengers and decay (The Burgess Shale Geoscience Foundation 2010).
Some of the fossils found in the Burgess Shale Formation are ancestors
to modern animals, but many are unique to the Cambrian period. Between
1910 and 1924, Walcott extracted over 65,000 specimens from the Burgess
Shale Formation, including arthropods, worms, sponges, lophophorates,
echinoderms, mollusks, and chordates (The Burgess Shale Geoscience Foundation
2010). The majority of the fossils were extracted from the upper quarry
of the area, called Walcott’s quarry. In 1981, UNESCO designated
the site as a heritage site, preserving it forever as an important clue
to our evolutionary history.
Page by Juia Bobo
|Top: Picture of Charles D. Walcott in 1909 at the Burgess Shale Formation, from The Smithsonian Institution. Bottom: Trilobite Fossil from the nearby Mt. Stevens Trilobite beds. Photo from www.msnbc.com.|
The Burgess Shale Geoscience Foundation. 2010. The Burgess Shale Formation: Introduction. Accessed February 1, 2010.
Scott E, Kirkner L, Shin J, Desar V, Chan J. 2000. The Burgess Shale. University of California Museum of Paleontology. Accessed January 28th, 2010.
Encyclopaedia Britannia Online. 2010. Burgess Shale. Retrieved January 28th, 2010.