Journal ArticleDOI
Establishing a time-scale for plant evolution
TLDR
A post-Jurassic origin of angiosperms and a post-Cambrian origin of land plants are rejected, and it is suggested that the establishment of the major embryophyte lineages occurred at a much slower tempo than suggested in most previous studies.Abstract:
• Plants have utterly transformed the planet, but testing hypotheses of causality requires a reliable time-scale for plant evolution. While clock methods have been extensively developed, less attention has been paid to the correct interpretation and appropriate implementation of fossil data. • We constructed 17 calibrations, consisting of minimum constraints and soft maximum constraints, for divergences between model representatives of the major land plant lineages. Using a data set of seven plastid genes, we performed a cross-validation analysis to determine the consistency of the calibrations. Six molecular clock analyses were then conducted, one with the original calibrations, and others exploring the impact on divergence estimates of changing maxima at basal nodes, and prior probability densities within calibrations. • Cross-validation highlighted Tracheophyta and Euphyllophyta calibrations as inconsistent, either because their soft maxima were overly conservative or because of undetected rate variation. Molecular clock analyses yielded estimates ranging from 568-815 million yr before present (Ma) for crown embryophytes and from 175-240 Ma for crown angiosperms. • We reject both a post-Jurassic origin of angiosperms and a post-Cambrian origin of land plants. Our analyses also suggest that the establishment of the major embryophyte lineages occurred at a much slower tempo than suggested in most previous studies. These conclusions are entirely compatible with current palaeobotanical data, although not necessarily with their interpretation by palaeobotanists.read more
Citations
More filters
Journal ArticleDOI
A metacalibrated time-tree documents the early rise of flowering plant phylogenetic diversity
TL;DR: This time-frame documents an early phylogenetic proliferation that led to the establishment of major angiosperm lineages, and the origin of over half of extant families, in the Cretaceous.
Journal Article
Accounting for calibration uncertainty in phylogenetic estimation of evolutionary divergence times
TL;DR: A variety of local and relaxed clock methods have been proposed and implemented for phylogenetic divergence dating as discussed by the authors, which allows different molecular clocks in different parts of the phylogenetic tree, thereby retaining the advantages of the classical molecular clock while casting off the restrictive assumption of a single, global rate of substitution.
Journal ArticleDOI
Best practices for justifying fossil calibrations
James F. Parham,James F. Parham,James F. Parham,Philip C. J. Donoghue,Christopher J. Bell,Tyler Calway,Jason J. Head,Patricia A. Holroyd,Jun G. Inoue,Randall B. Irmis,Walter G. Joyce,Daniel T. Ksepka,Daniel T. Ksepka,José S. L. Patané,Nathan D. Smith,Nathan D. Smith,James E. Tarver,James E. Tarver,Marcel van Tuinen,Ziheng Yang,Kenneth D. Angielczyk,Jenny M. Greenwood,Christy A. Hipsley,Christy A. Hipsley,Louis L. Jacobs,Peter J. Makovicky,Johannes Müller,Krister T. Smith,Jessica M. Theodor,Rachel C. M. Warnock,Michael J. Benton +30 more
TL;DR: A specimen-based protocol for selecting and documenting relevant fossils is presented and future directions for evaluating and utilizing phylogenetic and temporal data from the fossil record are discussed, to establish the best practices for justifying fossils used for the temporal calibration of molecular phylogenies.
Journal ArticleDOI
The timescale of early land plant evolution
Jennifer L. Morris,Mark N. Puttick,James W. Clark,Dianne Edwards,Paul Kenrick,Silvia Pressel,Charles H. Wellman,Ziheng Yang,Ziheng Yang,Harald Schneider,Philip C. J. Donoghue +10 more
TL;DR: 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 is established.
Journal ArticleDOI
Estimating divergence times in large molecular phylogenies
Koichiro Tamura,Fabia U. Battistuzzi,Fabia U. Battistuzzi,Paul Billing-Ross,Oscar Murillo,Alan Filipski,Sudhir Kumar +6 more
TL;DR: RelTime is presented, a method that estimates relative times of divergences for all branching points (nodes) in very large phylogenetic trees without assuming a specific model for lineage rate variation or specifying any clock calibrations.
References
More filters
Journal ArticleDOI
Earth's oldest liverworts—Metzgeriothallus sharonae sp. nov. from the Middle Devonian (Givetian) of eastern New York, USA
TL;DR: This article showed that liverworts are locally quite common as well-preserved, apparently parautochthonous specimens in thin, lenticular, dark gray-black shale and siltstone lenses.
Journal ArticleDOI
Thucydiaceae Fam. Nov., with a Review and Reevaluation of Paleozoic Walchian Conifers
TL;DR: Thucydia is the only conifer with ovuliferous fertile zones, compound pollen cones, and dissimilar stomatal distributions on vegetative and fertile leaves and provides a benchmark for developing sound taxonomic concepts and useful criteria for identifying specimens of walchian species and for resolving phylogenetic relationships among fossil and living conifers.
Journal ArticleDOI
A late Wenlock flora from Co. Tipperary, Ireland
TL;DR: It is concluded that these plants provide the earliest record of erect fertile land plants of possible pteridophyte affinity and sedimentological and palaeontological studies of the region provide little direct evidence for the habitats of the plants which are considered to have been terrestrial.
Journal ArticleDOI
Quantitative geomorphology of the Mars Eberswalde delta
TL;DR: The Eberswalde delta is composed of six separate depositional lobes that have prograded some 17 km from their apex as discussed by the authors, and they are clearly visible in images acquired by the Mars Global Surveyor Mars Orbiter Camera.
Journal ArticleDOI
Normapolles and triporate pollen assemblages from the Raritan and Magothy Formations (Upper Cretaceous) of New Jersey
TL;DR: In this paper, a principal coordinates analysis was performed on the Normapolles and triporate pollen from selected lithologic units of the Raritan and Magothy Formations.
Related Papers (5)
Relaxed Phylogenetics and Dating with Confidence
The age and diversification of the angiosperms re-revisited
Bayesian Estimation of Species Divergence Times Under a Molecular Clock Using Multiple Fossil Calibrations with Soft Bounds
Ziheng Yang,Bruce Rannala +1 more