Anomalocaris, the “strange shrimp” that is not a shrimp at all, but makes for a lovely Cambrian poster-child
– National Science Foundation

The Burgess Shale outcrops are located near Field, British Columbia
– T. Koleszar

The sites are managed by Parks Canada, who have installed informative signs along trails in the area. This one’s at Emerald Lake
– T. Koleszar

Wapta Mountain and Fossil Ridge as see from Emerald Lake. The Walcott Quarry is in the center-right
– T. Koleszar

Here are the various quarries subseqently established in the area
– T. Koleszar

Charles Walcott in the field circa 1910
– Smithsonian Institution

This is the quarry that now bears his name
– T. Koleszar

The first Anomalocaris fossil ever recovered, now at the Royal Ontario Museum
– K. Schengili-Roberts

Anomalocaris was the largest predator of the Cambrian oceans, with some specimens up to a metre long. In this depiction it is chasing trilobites
– K. Doud

Global distribution of Burgess Shale type formations
– Virtual Museum of Canada

A lot happened in a short (by geological standards) period of time. Many phyla that emerged during the Cambrian were ultimately “failed experiments”
– Harper and Smith (2013)

Just a few of the oddballs. From left to right we have Anomalocaris, Wiwaxia, and Marella. These are all “unassigned forms”, with no clear signs of ancestral linkage to any surviving group
– T. Koleszar

This is Haplophrentis carinatus, part of another group that is long extinct
– Smithsonian

The soft-tissue level of detail preserved in the rocks is truly mind-blowing. This is a reconstruction of Marella splendens
– montage by Haug et al. (2012)

Where else can one pursue earth-shaking science amidst such splendor? Emerald Lake as seen from the Walcott quarry
– T. Koleszar

Another view of Fossil Ridge
– T. Koleszar

And if you get bored looking at rocks
– T. Koleszar

You can follow these fellows
– T. Koleszar

all the way to Stanley Glacier, and beyond!
– T. Koleszar

Tom Koleszar – “Exploring the Burgess Shale”
by Andrew Bryant, 19 Mar 2015. 

Tom Koleszar, geologist and vice-president of our club, took us on a sweeping, half-billion year-old exploration of the Burgess Shale.

This extraordinary rock formation, located in Yoho and Kootenay National Parks in the Canadian Rockies, contains one of the world’s richest deposits of fossils.  It is renowned for the quality of its fossils, especially as they allow for the preservation of soft-tissue imprints.   You can learn much more about it here, here and here.

It is truly extraordinary to look at a 500 million-year old rock and be able to count delicate hairs, eye facets or mouthpart details on an organism that was only millimetres or centimetres long when it swam or crawled through prehistoric seas.

Using photos, maps, and wit, Tom intoduced us to the fascinating world of the Cambrian, an epoch during which the oceans exploded into life.  To decribe creatures such as Anomalocaris, Hallucigenia and Opabinia as “strange” is a severe understatement – some of these things are downright weird!

There is also some fascinating human history surrounding these rocks, including that of discoverer Charles Walcott, who impressed his hardworking family into field technicians and porters, and the unresolved scientific debate between people such as Stephen Jay Gould and Simon Conway Morris.

Was the “Cambrian explosion” just a series of failed experiments in body type design?  Or the beginning of phyla that can be traced to this day?

As they say.  Time will tell.