Abstract:
:Bones from a stratified sedimentary deposit in the Puu Naio Cave site on Maui, Hawaiian Islands, reveal the late Holocene extinction of 19 species of birds. The age of the sediment and associated fauna was determined by direct radiocarbon dating (tandem particle accelerator-mass spectrometer; TAMS) of amino acids extracted from bones weighing as little as 450 mg. The 14C dates indicate that sediment has been accumulating in the lava tube for at least the last 7750 years, a suitable time frame for testing the hypothesis that Holocene extinction on islands began after human colonization. Despite growing evidence that a worldwide wave of extinctions coincided with human colonization of oceanic islands, little radiometric data have been available to date the extinction of most small fossil vertebrates on islands. The TAMS technique of dating purified collagen from the bones of small vertebrates could lead to vastly improved chronologies of extinction for oceanic islands where catastrophic mid- to late-Holocene extinction is expected or known to have occurred. Chronologies derived from nonarcheological sites that show continuous sedimentation, such as the Puu Naio Cave deposit, may also yield key evidence on the timing of earliest human settlement of Oceania.
journal_name
Proc Natl Acad Sci U S Aauthors
James HF,Stafford TW Jr,Steadman DW,Olson SL,Martin PS,Jull AJ,McCoy PCdoi
10.1073/pnas.84.8.2350subject
Has Abstractpub_date
1987-04-01 00:00:00pages
2350-4issue
8eissn
0027-8424issn
1091-6490journal_volume
84pub_type
杂志文章abstract::Aged rats, displaying impairments in spatial learning and memory associated with marked cellular atrophy of forebrain cholinergic neurons, received intracerebroventricular infusions of one of the four neurotrophins nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), neurotrophin 3 (NT-3), or neurotrop...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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doi:10.1073/pnas.91.18.8607
更新日期:1994-08-30 00:00:00
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doi:10.1073/pnas.1219937110
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2009-05-12 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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更新日期:1974-04-01 00:00:00
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更新日期:1974-03-01 00:00:00
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更新日期:1989-06-01 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2012-03-06 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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更新日期:1984-06-01 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2018-11-06 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2013-12-10 00:00:00