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| caption = ''Ottoia'', a soft-bodied worm, abundant in the Burgess Shale. (From Smith et al. 2015) | type = Geological formation | prilithology = Shale | otherlithology = | namedfor = Burgess Pass | namedby = Charles Doolittle Walcott, 1911 | region = Yoho National Park and Kootenay National Park | country = Canada | coordinates = | unitof = Stephen Formation | subunits = | thickness = 〔(【引用サイトリンク】title=Burgess Shale )〕 | extent = | area = | map = Canadian Rockies highlighting Yoho National Park.png | map_caption = Map highlighting Yoho National Park in red }} The Burgess Shale Formation is a fossiliferous deposit exposed in the Canadian Rockies of British Columbia, Canada. It is famous for the exceptional preservation of the soft parts of its fossils. At (Middle Cambrian) old, it is one of the earliest fossil beds containing soft-part imprints. The rock unit is a black shale and crops out at a number of localities near the town of Field in Yoho National Park and the Kicking Horse Pass. Another outcrop is in Kootenay National Park 42 km to the south. == History and significance == (詳細はpalaeontologist Charles Walcott on 30 August 1909,〔(【引用サイトリンク】 title=Charles Walcott )〕 towards the end of the season's fieldwork. He returned in 1910 with his sons, daughter, and wife, establishing a quarry on the flanks of Fossil Ridge. The significance of soft-bodied preservation, and the range of organisms he recognised as new to science, led him to return to the quarry almost every year until 1924. At that point, aged 74, he had amassed over 65,000 specimens. Describing the fossils was a vast task, pursued by Walcott until his death in 1927.〔Fossils of the Burgess Shale〕 Walcott, led by scientific opinion at the time, attempted to categorise all fossils into living taxa, and as a result, the fossils were regarded as little more than curiosities at the time. It was not until 1962 that a first-hand reinvestigation of the fossils was attempted, by Alberto Simonetta. This led scientists to recognise that Walcott had barely scratched the surface of information available in the Burgess Shale, and also made it clear that the organisms did not fit comfortably into modern groups. Excavations were resumed at the Walcott Quarry by the Geological Survey of Canada under the persuasion of trilobite expert Harry Blackmore Whittington, and a new quarry, the Raymond, was established about 20 metres higher up Fossil Ridge.〔 Whittington, with the help of research students Derek Briggs and Simon Conway Morris of the University of Cambridge, began a thorough reassessment of the Burgess Shale, and revealed that the fauna represented were much more diverse and unusual than Walcott had recognized.〔 Indeed, many of the animals present had bizarre anatomical features and only the slightest resemblance to other known animals. Examples include ''Opabinia'', with five eyes and a snout like a vacuum cleaner hose and ''Hallucigenia'', which was originally reconstructed upside down, walking on bilaterally symmetrical spines. With Parks Canada and UNESCO recognising the significance of the Burgess Shale, collecting fossils became politically more difficult from the mid-1970s. Collections continued to be made by the Royal Ontario Museum. The curator of invertebrate palaeontology, Desmond Collins, identified a number of additional outcrops, stratigraphically both higher and lower than the original Walcott quarry.〔 These localities continue to yield new organisms faster than they can be studied. Stephen Jay Gould's book ''Wonderful Life'', published in 1989, brought the Burgess Shale fossils to the public's attention. Gould suggests that the extraordinary diversity of the fossils indicates that life forms at the time were much more disparate in body form than those that survive today, and that many of the unique lineages were evolutionary experiments that became extinct. Gould's interpretation of the diversity of Cambrian fauna relied heavily on Simon Conway Morris' reinterpretation of Charles Walcott's original publications. However, Conway Morris strongly disagreed with Gould's conclusions, arguing that almost all the Cambrian fauna could be classified into modern day phyla. The Burgess Shale has attracted the interest of paleoclimatologists who want to study and predict long-term future changes in Earth's climate. According to Peter Ward and Donald Brownlee in the 2003 book ''The Life and Death of Planet Earth'', climatologists study the fossil records in the Burgess Shale to understand the climate of the Cambrian Explosion, and use it to predict what Earth's climate in the future when a warming and expanding Sun combined with declining CO2 levels eventually heat the Earth toward temperatures not seen since the first plants and animals, and therefore understand how and when the last living things will die out. In February 2014, the discovery was announced of another Burgess Shale outcrop in Kootenay National Park to the south. In just 15 days of field collecting in 2013, 50 animal species were unearthed at the new site. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Burgess Shale」の詳細全文を読む スポンサード リンク
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