Abstract:
:Evolutionary processes leading to adaptive radiation regularly occur too fast to be accurately recorded in the fossil record but too slowly to be readily observed in living biota. The study of evolutionary radiations is thereby confronted with an epistemological gap between the timescales and approaches used by neontologists and paleontologists. Here we report on an ongoing radiation of extant Bellamya species (n = 4) from the African Rift Lake Malawi that provides an unusual opportunity to bridge this gap. The substantial molecular differentiation in this monophyletic Bellamya clade has arisen since Late Pleistocene megadroughts in the Malawi Basin caused by climate change. Morphological time-series analysis of a high-resolution, radiocarbon-dated sequence of 22 faunas spanning the Holocene documents stasis up to the middle Holocene in all traits studied (shell height, number of whorls, and two variables obtained from geometric morphometrics). Between deposition of the last fossil fauna (~5 ka) and the present day, a drastic increase in morphological disparity was observed (3.7-5.8 times) associated with an increase in species diversity. Comparison of the rates of morphological evolution obtained from the paleontological time-series with phylogenetic rates indicates that the divergence in two traits could be reconstructed with the slow rates documented in the fossils, that one trait required a rate reduction (stabilizing selection), and the other faster rates (divergent selection). The combined paleontological and comparative approach taken here allows recognition that morphological stasis can be the dominant evolutionary pattern within species lineages, even in very young and radiating clades.
journal_name
Proc Natl Acad Sci U S Aauthors
Van Bocxlaer B,Hunt Gdoi
10.1073/pnas.1308588110subject
Has Abstractpub_date
2013-08-20 00:00:00pages
13892-7issue
34eissn
0027-8424issn
1091-6490pii
1308588110journal_volume
110pub_type
杂志文章abstract::Cell cycle checkpoints are evolutionarily conserved surveillance systems that protect genomic stability and prevent oncogenesis in mammals. One important target of checkpoint control is ribonucleotide reductase (RNR), which catalyzes the rate-limiting step in dNTP and DNA synthesis. In both yeast and humans, RNR is tr...
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:2002-03-19 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:1984-12-01 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:2000-12-19 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:2014-12-16 00:00:00
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更新日期:2017-01-17 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:1995-03-14 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:1986-10-01 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
doi:10.1073/pnas.77.5.2555
更新日期:1980-05-01 00:00:00
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pub_type: 杂志文章
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更新日期:2005-11-08 00:00:00
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pub_type: 杂志文章
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更新日期:2002-06-25 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
doi:10.1073/pnas.84.15.5177
更新日期:1987-08-01 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:1993-11-15 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:1998-03-17 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
doi:10.1073/pnas.93.25.14328
更新日期:1996-12-10 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:2011-08-23 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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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:1984-03-01 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:2008-03-25 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:2011-09-13 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:1992-06-15 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:1985-04-01 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:2013-10-01 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:2014-01-07 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
doi:10.1073/pnas.89.8.3439
更新日期:1992-04-15 00:00:00
abstract::Capsaicin is a unique alkaloid of the plant kingdom restricted to the genus Capsicum. Capsaicin is the pungency factor, a bioactive molecule of food and of medicinal importance. Capsaicin is useful as a counterirritant, antiarthritic, analgesic, antioxidant, and anticancer agent. Capsaicin biosynthesis involves conden...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章,收录出版
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更新日期:2006-09-05 00:00:00
abstract::Pleistocene residential sites with multiple contemporaneous human burials are extremely rare in the Americas. We report mitochondrial genomic variation in the first multiple mitochondrial genomes from a single prehistoric population: two infant burials (USR1 and USR2) from a common interment at the Upward Sun River Si...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 历史文章,杂志文章
doi:10.1073/pnas.1511903112
更新日期:2015-11-10 00:00:00