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The Burgess shale (named after Mount Burgess , near where the shale was found) is a black shale found high up in the Canadian Rockies in Yoho National Park near the town of Field, British Columbia. Fossils were found in the Burgess Shale by C. D. Walcott in 1909. Walcott returned in the following years to collect additional specimens. The majority of the fossils collected were unique to the site, although some common Middle Cambrian trilobites were also found. The fossils were of substantial interest because they included appendages and soft parts that are rarely preserved.The significance of these finds was not realised at the time. A reinvestigation of the fossils in the 1980s by Henry Wittington , Derek Briggs , and Simon Conway Morris of the University of Cambridge revealed that the fauna represented was much more diverse and unusual than Walcott had recognized. Indeed, many of the animals present had bizarre anatomical features and only the sketchiest resemblance to other known animals. Examples include Opabinia with five eyes and a snout like a vacuum cleaner; Aysheaia which bears an extraordinary resemblance to a minor modern phylum -- the Onychophora; Nectocaris which is apparently either a crustaceanCrustaceans Hyalella azteca Scientific classification Kingdom: Animalia Phylum: Arthropoda Subphylum Crustacea Classes Remipedia Cephalocarida Branchiopoda Ostracoda Maxillopoda Malacostraca The crustaceans (Crustacea) are a large group of arthropods (55, with fins or a vertebratePetromyzontidae ( lampreys) Placodermi extinct Chondrichthyes (cartilaginous fish) Acanthodii extinct Actinopterygii (ray-finned fish) Actinistia ( coelacanths) Dipnoi ( lungfish) Amphibia ( amphibians) Reptilia ( reptiles) Aves ( birds) Mammalia ( mammal with a shell; and HallucigeniaNote: taxonomic status very uncertain Hallucigenia is an extinct animal genus found as fossils in the Middle Cambrian-aged Burgess Shale formation of British Columbia, Canada. It was named by Simon Conway Morris when he re-examined Charles Walcott's Burge which was originally reconstructed as walking on bilaterally symmetrical spines. Conway-Morris now reconstructs it as another onychophoran, with the spines on its back. Several poorly understood fossils were found to be body parts of a predatory form known as AnomalocarisAnomalocaridae Anomalocarids,extinct Genus Anomalocaris Genus Laggania Genus Parapeytoia Opabinidae Extinct Genus Opabinia Unclassified anomalocarid-like specimens Genus Kerygmachela Genus Pambdelurion Anomalocarids (meaning "odd shrimp") are a group of v. More recent (late 1990s) work by Derek Briggs and Richard Fortey has placed many of the "peculiar" Burgess Shale fossils within the arthropodSubphylum Trilobitomorpha Trilobita Trilobites (extinct) Subphylum Chelicerata Arachnida Spiders, Scorpions, etc. Merostomata Horseshoe crabs, etc. Pycnogonida Sea Spiders Subphylum Myriapoda Chilopoda Centipedes Diplopoda Millipedes Pauropoda Symphyla Sua, but many animals such as AmiskwiaAmiskwia is a small, probably gelatinous animal of unknown affinity known from fossils of the Middle Cambrian Burgess shale formation in British Columbia. The preservation of the five known specimens leaves much to be desired. Fossil size is up to 1 inch remain enigmatic.
A popular account of the 1980s analysis of the Burgess Shale is given in Wonderful LifeWonderful Life (1989) is a book on evolution by Stephen Jay Gould. It was the 1991 winner of The Aventis Prizes for Science Books. In this book, Gould presents his thesis that contingency (luck) was one of the decisive factors in the evolution of life on by Stephen Jay GouldStephen Jay Gould ( September 10, 1941 May 20, 2002) was a New York-born American paleontologist, an evolutionary biologist and historian of science. He was the most influential and widely-read writer of research-based popular science of his generation..
The diversity and exotic nature of the Burgess fauna has caused a great deal of controversy in paleontology with regard to the reasons for and nature of what has come to be called the Cambrian Explosion.
Further investigations showed that the Burgess Shale extends for many miles in isolated outcrops and the various faunas are preserved in different places. The deposits appear to represent small areas of muddy ocean bottom that -- from time to time -- slid down the face of a limestone cliff, carrying their fauna and anything unfortunate enough to be swimming by into oxygen-poor waters in the depths. Six distinct faunal zones have been identified in the Burgess Shale. Now that scientists know what to look for, similar deposits have been identified elsewhere with similar faunas. The most important similar deposits are even older turbide flow deposit s created in much the same way as the Burgess shales in Yunnan Province, China. These Maotianshan shales contain fauna quite similar to the Burgess.
Due to its location within Yoho National Park, the shale is part of a UNESCO World Heritage Site, specifically, the Canadian Rocky Mountain Parks. Subsequent exploration has found exposures of the shale over a front of several dozen kilometers and has identified at least six fossiliferous lagerstätten within the formation.
