The timescale of early land plant evolution

	The timescale of early land plant evolution
	Morris, Jennifer L.; Puttick, Mark N.; Clark, James W.; Edwards, Dianne; Kenrick, Paul; Pressel, Silvia; Wellman, Charles H.; Yang, Ziheng; Schneider, Harald; Donoghue, Philip C. J.
刊名	PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
	2018
卷号	115 期号:10 页码:E2274-E2283
关键词	Plant Evolution Timescale Phylogeny Embryophyta
ISSN号	0027-8424
英文摘要	Establishing the timescale of early land plant evolution is essential for testing hypotheses on the coevolution of land plants and Earth's System. The sparseness of early land plant megafossils and stratigraphic controls on their distribution make the fossil record an unreliable guide, leaving only the molecular clock. However, the application of molecular clock methodology is challenged by the current impasse in attempts to resolve the evolutionary relationships among the living bryophytes and tracheophytes. Here, we establish a timescale for early land plant evolution that integrates over topological uncertainty by exploring the impact of competing hypotheses on bryophyte-tracheophyte relationships, among other variables, on divergence time estimation. We codify 37 fossil calibrations for Viridiplantae following best practice. We apply these calibrations in a Bayesian relaxed molecular clock analysis of a phylogenomic dataset encompassing the diversity of Embryophyta and their relatives within Viridiplantae. Topology and dataset sizes have little impact on age estimates, with greater differences among alternative clock models and calibration strategies. For all analyses, a Cambrian origin of Embryophyta is recovered with highest probability. The estimated ages for crown tracheophytes range from Late Ordovician to late Silurian. This timescale implies an early establishment of terrestrial ecosystems by land plants that is in close accord with recent estimates for the origin of terrestrial animal lineages. Biogeochemical models that are constrained by the fossil record of early land plants, or attempt to explain their impact, must consider the implications of a much earlier, middle Cambrian-Early Ordovician, origin.
URL标识	查看原文
公开日期	2018-04-10
内容类型	期刊论文
源URL	[http://ir.xtbg.org.cn/handle/353005/10812]
专题	西双版纳热带植物园_其他
推荐引用方式 GB/T 7714	Morris, Jennifer L.,Puttick, Mark N.,Clark, James W.,et al. The timescale of early land plant evolution[J]. PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA,2018,115(10):E2274-E2283.
APA	Morris, Jennifer L..,Puttick, Mark N..,Clark, James W..,Edwards, Dianne.,Kenrick, Paul.,...&Donoghue, Philip C. J..(2018).The timescale of early land plant evolution.PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA,115(10),E2274-E2283.
MLA	Morris, Jennifer L.,et al."The timescale of early land plant evolution".PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA 115.10(2018):E2274-E2283.