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Uncertainty in the Timing of Origin of Animals and the Limits of Precision in Molecular Timescales
The timing of divergences among metazoan lineages is integral to understanding the processes of animal evolution, placing the biological events of species divergences into the correct geological timeframe. Recent fossil discoveries and molecular clock dating studies have suggested a divergence of bi...
Autores principales: | , , , , , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
Cell Press
2015
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4651906/ https://www.ncbi.nlm.nih.gov/pubmed/26603774 http://dx.doi.org/10.1016/j.cub.2015.09.066 |
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author | dos Reis, Mario Thawornwattana, Yuttapong Angelis, Konstantinos Telford, Maximilian J. Donoghue, Philip C.J. Yang, Ziheng |
author_facet | dos Reis, Mario Thawornwattana, Yuttapong Angelis, Konstantinos Telford, Maximilian J. Donoghue, Philip C.J. Yang, Ziheng |
author_sort | dos Reis, Mario |
collection | PubMed |
description | The timing of divergences among metazoan lineages is integral to understanding the processes of animal evolution, placing the biological events of species divergences into the correct geological timeframe. Recent fossil discoveries and molecular clock dating studies have suggested a divergence of bilaterian phyla >100 million years before the Cambrian, when the first definite crown-bilaterian fossils occur. Most previous molecular clock dating studies, however, have suffered from limited data and biases in methodologies, and virtually all have failed to acknowledge the large uncertainties associated with the fossil record of early animals, leading to inconsistent estimates among studies. Here we use an unprecedented amount of molecular data, combined with four fossil calibration strategies (reflecting disparate and controversial interpretations of the metazoan fossil record) to obtain Bayesian estimates of metazoan divergence times. Our results indicate that the uncertain nature of ancient fossils and violations of the molecular clock impose a limit on the precision that can be achieved in estimates of ancient molecular timescales. For example, although we can assert that crown Metazoa originated during the Cryogenian (with most crown-bilaterian phyla diversifying during the Ediacaran), it is not possible with current data to pinpoint the divergence events with sufficient accuracy to test for correlations between geological and biological events in the history of animals. Although a Cryogenian origin of crown Metazoa agrees with current geological interpretations, the divergence dates of the bilaterians remain controversial. Thus, attempts to build evolutionary narratives of early animal evolution based on molecular clock timescales appear to be premature. |
format | Online Article Text |
id | pubmed-4651906 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2015 |
publisher | Cell Press |
record_format | MEDLINE/PubMed |
spelling | pubmed-46519062015-12-09 Uncertainty in the Timing of Origin of Animals and the Limits of Precision in Molecular Timescales dos Reis, Mario Thawornwattana, Yuttapong Angelis, Konstantinos Telford, Maximilian J. Donoghue, Philip C.J. Yang, Ziheng Curr Biol Article The timing of divergences among metazoan lineages is integral to understanding the processes of animal evolution, placing the biological events of species divergences into the correct geological timeframe. Recent fossil discoveries and molecular clock dating studies have suggested a divergence of bilaterian phyla >100 million years before the Cambrian, when the first definite crown-bilaterian fossils occur. Most previous molecular clock dating studies, however, have suffered from limited data and biases in methodologies, and virtually all have failed to acknowledge the large uncertainties associated with the fossil record of early animals, leading to inconsistent estimates among studies. Here we use an unprecedented amount of molecular data, combined with four fossil calibration strategies (reflecting disparate and controversial interpretations of the metazoan fossil record) to obtain Bayesian estimates of metazoan divergence times. Our results indicate that the uncertain nature of ancient fossils and violations of the molecular clock impose a limit on the precision that can be achieved in estimates of ancient molecular timescales. For example, although we can assert that crown Metazoa originated during the Cryogenian (with most crown-bilaterian phyla diversifying during the Ediacaran), it is not possible with current data to pinpoint the divergence events with sufficient accuracy to test for correlations between geological and biological events in the history of animals. Although a Cryogenian origin of crown Metazoa agrees with current geological interpretations, the divergence dates of the bilaterians remain controversial. Thus, attempts to build evolutionary narratives of early animal evolution based on molecular clock timescales appear to be premature. Cell Press 2015-11-16 /pmc/articles/PMC4651906/ /pubmed/26603774 http://dx.doi.org/10.1016/j.cub.2015.09.066 Text en © 2015 The Authors http://creativecommons.org/licenses/by/4.0/ This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/). |
spellingShingle | Article dos Reis, Mario Thawornwattana, Yuttapong Angelis, Konstantinos Telford, Maximilian J. Donoghue, Philip C.J. Yang, Ziheng Uncertainty in the Timing of Origin of Animals and the Limits of Precision in Molecular Timescales |
title | Uncertainty in the Timing of Origin of Animals and the Limits of Precision in Molecular Timescales |
title_full | Uncertainty in the Timing of Origin of Animals and the Limits of Precision in Molecular Timescales |
title_fullStr | Uncertainty in the Timing of Origin of Animals and the Limits of Precision in Molecular Timescales |
title_full_unstemmed | Uncertainty in the Timing of Origin of Animals and the Limits of Precision in Molecular Timescales |
title_short | Uncertainty in the Timing of Origin of Animals and the Limits of Precision in Molecular Timescales |
title_sort | uncertainty in the timing of origin of animals and the limits of precision in molecular timescales |
topic | Article |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4651906/ https://www.ncbi.nlm.nih.gov/pubmed/26603774 http://dx.doi.org/10.1016/j.cub.2015.09.066 |
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