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DOI	10.1073/pnas.2103517118
	Revisiting the sedimentary record of the rise of diatoms
	Westacott S.; Planavsky N.J.; Zhao M.-Y.; Hull P.M.
发表日期	2021
ISSN	0027-8424
卷号	118 期号:27
英文摘要	Diatoms are a major primary producer in the modern oceans and play a critical role in the marine silica cycle. Their rise to dominance is recognized as one of the largest shifts in Cenozoic marine ecosystems, but the timing of this transition is debated. Here, we use a diagenetic model to examine the effect of sedimentation rate and temperature on the burial efficiency of biogenic silica over the past 66 million years (i.e., the Cenozoic). We find that the changing preservation potential of siliceous microfossils during that time would have overprinted the primary signal of diatom and radiolarian abundance. We generate a taphonomic null hypothesis of the diatom fossil record by assuming a constant flux of diatoms to the sea floor and having diagenetic conditions driven by observed shifts in temperature and sedimentation rate. This null hypothesis produces a late Cenozoic (∼5 Ma to 20 Ma) increase in the relative abundance of fossilized diatoms that is comparable to current empirical records. This suggests that the observed increase in diatom abundance in the sedimentary record may be driven by changing preservation potential. A late Cenozoic rise in diatoms has been causally tied to the rise of grasslands and baleen whales and to declining atmospheric CO2 levels. Here we suggest that the similarity among these records primarily arises from a common driver-the cooling climate system-that drove enhanced diatom preservation as well as the rise of grasslands and whales, rather than a causal link among them. © 2021 National Academy of Sciences. All rights reserved.
英文关键词	Diagenesis; Diatom evolution; Fossil record; Silica
语种	英语
scopus关键词	carbon dioxide; silicon dioxide; Article; baleen whale; Cenozoic; diagenesis; diatom; environmental temperature; grassland; microfossil; nonhuman; null hypothesis; population abundance; sediment; sedimentation; temperature measurement
来源期刊	Proceedings of the National Academy of Sciences of the United States of America
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/238496
作者单位	Department of Earth and Planetary Sciences, Yale University, New Haven, CT 06511, United States
推荐引用方式 GB/T 7714	Westacott S.,Planavsky N.J.,Zhao M.-Y.,et al. Revisiting the sedimentary record of the rise of diatoms[J],2021,118(27).
APA	Westacott S.,Planavsky N.J.,Zhao M.-Y.,&Hull P.M..(2021).Revisiting the sedimentary record of the rise of diatoms.Proceedings of the National Academy of Sciences of the United States of America,118(27).
MLA	Westacott S.,et al."Revisiting the sedimentary record of the rise of diatoms".Proceedings of the National Academy of Sciences of the United States of America 118.27(2021).