And then you just have to keep going. Walcott identified his specimens as members of extinct or modern groups, such as the arthropods shrimp, crabs, insects and the like or annelids segmented worms. In , paleontologist Stephen Jay Gould popularized Burgess' "weird wonders" in his bestselling book Wonderful Life. But he argued that Walcott had erroneously shoehorned the fossils into existing taxonomic groups.
He suggested that the curious "problematica" fossils that had long defied scientific identification—such as Hallucigenia , an inch-long creature with two rows of spines on its back—deserved their own taxonomic groupings. Lately, paleontologists have begun re-examining the classifications yet again, largely in response to the discovery of Burgess-type fossils in Australia, China, Greenland, Russia, Spain and the United States.
With more specimens, scientists are better able to see similarities among animals, and so they are shifting their emphasis from unique to shared characteristics. After a week of slim pickings at Walcott Quarry, Caron and his tired, sore team were ready to try a new location. Caron climbed aboard a helicopter to scout nearby mountain peaks for new sites to explore in the future.
He was joined by Robert Gaines, a Pomona College geologist who studies the shale millimeter by millimeter to figure out whether the various layers represent millennia of accumulated sediment or a few moments' worth deposited by storm currents. From the chopper Gaines saw a number of promising spots. He was keen to get on the ground and get out his measuring tape.
The helicopter put down near Stanley Glacier, where Caron and Gaines joined the rest of the crew, who were already prospecting for fossils. It did not take long to hit pay dirt. On the first afternoon, Loxton found a fossil of a species fondly known as Creeposaurus until it can be properly studied, identified and given its scientific name.
Caron called out: "Champagne! The Burgess Shale fossils are about million years old, some 20 million years younger than those from Chengjiang.
In fact, the Burgess Shale and Chengjiang have considerable overlap in faunal forms. Less well known is that Cambrian formations in the House Range of Utah yield many fossils like the Burgess Shale, though the soft tissue preservation is usually not as good.
The Burgess Shale Formation comprises 10 separate members, the most famous being the Walcott Quarry Shale Member comprising the greater phyllopod bed. The Burgess Shale comprises shale, limestone and siltstone and extends in a large area in outcrops of the Stephen Formation that exhibite different faunal mixes.
The fossils of the Burgess Shale are preserved as black carbon films on black shales. Scientists long believed the deposits were formed when areas of muddy ocean floor slid into a lower place creating an anoxic oxygen-starved environment that was particularly favorable to fossilization because decay was inhibited.
More recent research that oxygen was continually present in the sediment. While there are older Cambrian Lagerstatten, the Burgess Shale was science's first glimpse of the Cambrian Explosion in the fossil record. Join one of our hikes for an unforgettable day half a billion years in the making.
Visit our Gallery page to see photos of the fossils, hiking trails, and the fossil sites. Please visit our FAQs page for information regarding the differences between the two fossil sites, accommodations in the area, local weather, and so much more.
Alternatively, please have a look at our Blog. Walcott Quarry. Discover the Burgess Shale for yourself.
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