DOI: 10.1016/j.quascirev.2017.06.031
Scopus记录号: 2-s2.0-85022344000
论文题名: A case of early Wisconsinan “over-chill”: New radiocarbon evidence for early extirpation of western camel (Camelops hesternus) in eastern Beringia
作者: Zazula G.D. ; MacPhee R.D.E. ; Southon J. ; Nalawade-Chavan S. ; Reyes A.V. ; Hewitson S. ; Hall E.
刊名: Quaternary Science Reviews
ISSN: 2773791
出版年: 2017
卷: 171 起始页码: 48
结束页码: 57
语种: 英语
英文关键词: Extinctions
; North America
; Paleontology
; Pleistocene
; Radiocarbon
Scopus关键词: Hydroxyproline
; Stratigraphy
; Extinctions
; North America
; Paleontology
; Pleistocene
; Radiocarbon
; Glacial geology
; amino acid
; extinction
; Last Glacial Maximum
; marine isotope stage
; paleontology
; Pleistocene
; radiocarbon dating
; ungulate
; Wisconsinan
; Alaska
; North America
; United States
; Camelidae
英文摘要: There are comparatively few fossils that document the presence of the Pleistocene western camel (Camelops hesternus) in the unglaciated regions of Alaska and Yukon, northwestern North America (eastern Beringia). It has been previously reported on the basis of stratigraphic and radiocarbon data that this species was present within this region from the Sangamonian interglaciation (Marine Isotope Stage (MIS) 5) through the Last Glacial Maximum (LGM, MIS 2). However, the continued presence of western camel through the LGM is at odds with its ecological preferences as inferred from more southerly parts of the continent. Here we report 43 new radiocarbon dates on 34 western camel fossils from Alaska and Yukon, including specimens that have been dated previously. To minimize exogenous carbon contamination, we utilized either ultrafiltered collagen or single amino acid (hydroxyproline) methodologies in conducting the analyses. All samples, including previously reported specimens with finite ages, yielded ages that were either non-finite or close to the effective limit of radiocarbon dating. These results indicate that dates implying local presence of western camels in Alaska and Yukon during full-glacial conditions of MIS 2 are erroneous by as much as several tens of millennia, probably because of carbon contamination from glue or varnish used in fossil preparation and conservation. The revised radiocarbon chronology, together with other evidence, indicates that western camels were only able to occupy eastern Beringia only during Pleistocene interglaciations such as MIS 5, when forests and shrublands became the dominant regional biomes. The subsequent transition to cold, arid full-glacial conditions during the early Wisconsinan glaciation (MIS 4) around 75 000 years ago created unfavorable environmental conditions, eliminated browse, and led to their local extirpation in eastern Beringia. After their complete population loss in the Arctic and Subarctic, the range of western camels was restricted to the temperate mid-continent, where they eventually went extinct ∼13 000 years ago. © 2017 Elsevier Ltd Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/59124
Appears in Collections: 过去全球变化的重建
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作者单位: Yukon Palaeontology Program, Government of Yukon, P.O. Box 2703, Whitehorse, Yukon, Canada; Department of Mammalogy, American Museum of Natural History, 200 Central Park West, New York, NY, United States; Keck-CCAMS Group, Earth System Science Department, B321 Croul Hall, University of California, Irvine, Irvine, CA, United States; Oxford Radiocarbon Accelerator Unit, Research Laboratory for Archaeology & History of Art, University of Oxford, Dyson Perrins Building, South Parks Road, Oxford, United Kingdom; Department of Earth and Atmospheric Sciences, University of Alberta, Edmonton, Alberta, Canada
Recommended Citation:
Zazula G.D.,MacPhee R.D.E.,Southon J.,et al. A case of early Wisconsinan “over-chill”: New radiocarbon evidence for early extirpation of western camel (Camelops hesternus) in eastern Beringia[J]. Quaternary Science Reviews,2017-01-01,171