Zazula, G. D.

7 items:

American mastodon extirpation in the Arctic and Subarctic predates human colonization and terminal Pleistocene climate change Existing radiocarbon (14C) dates on American mastodon (Mammut americanum) fossils from eastern Beringia (Alaska and Yukon) have been interpreted as evidence they inhabited the Arctic and Subarctic during Pleistocene full-glacial times ( approximately 18,000 14C years B.P.). However, this chronology is inconsistent with inferred habitat preferences of mastodons and correlative paleoecological evidence. To establish a last appearance date (LAD) for M. americanum regionally, we obtained 53 new 14C dates on 36 fossils, including specimens with previously published dates. Using collagen ultrafiltration and single amino acid (hydroxyproline) methods, these specimens consistently date to beyond or near the approximately... Categories: Data, Publication; Types: Citation, Downloadable, Map Service, OGC WFS Layer, OGC WMS Layer, Shapefile; Tags: Paleo and Holocene
New Spruce (Picea spp.) Macrofossils from Yukon Territory: Implications for Late Pleistocene Refugia in Eastern Beringia Categories: Publication; Types: Citation; Tags: Paleo and Holocene
American mastodon extirpation in the Arctic and Subarctic predates human colonization and terminal Pleistocene climate change Existing radiocarbon (14C) dates on American mastodon (Mammut americanum) fossils from eastern Beringia (Alaska and Yukon) have been interpreted as evidence they inhabited the Arctic and Subarctic during Pleistocene full-glacial times ( approximately 18,000 14C years B.P.). However, this chronology is inconsistent with inferred habitat preferences of mastodons and correlative paleoecological evidence. To establish a last appearance date (LAD) for M. americanum regionally, we obtained 53 new 14C dates on 36 fossils, including specimens with previously published dates. Using collagen ultrafiltration and single amino acid (hydroxyproline) methods, these specimens consistently date to beyond or near the approximately... Categories: Publication; Types: Citation; Tags: Paleo and Holocene
New Spruce (Picea spp.) Macrofossils from Yukon Territory: Implications for Late Pleistocene Refugia in Eastern Beringia Categories: Publication; Types: Citation; Tags: Paleo and Holocene
New Spruce (Picea spp.) Macrofossils from Yukon Territory: Implications for Late Pleistocene Refugia in Eastern Beringia Categories: Publication; Types: Citation; Tags: Paleo and Holocene

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