ArticleProceedings of the National Academy of Sciences of the United States of America2019
Trilobite evolutionary rates constrain the duration of the Cambrian explosion.
Article in Proceedings of the National Academy of Sciences of the United States of America, 2019. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 34 papers, 1 of them a synthesis that pooled it.
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34 citing papers in PubMed, 1 synthesis or guideline pooled it.
- Building phenotypic character matrices for phylogenetic inference: exploration of 35 years of practice.Biological reviews of the Cambridge Philosophical Society · 2026Pooled it
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- Rethinking therapsid phylogeny through Bayesian and cladistic approaches.Scientific reports · 2026Article
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- Combining fossil taxa with and without morphological data improves dated phylogenetic analyses.Biology letters · 2025Article
- Episodic body size variations of early Paleozoic trilobites associated with marine redox changes.Science advances · 2025Article
- Low oxygen but dynamic marine redox conditions permitted the Cambrian Radiation.Science advances · 2025Article
- Article
- The Emu Bay Shale: A unique early Cambrian Lagerstätte from a tectonically active basin.Science advances · 2024Article
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- Evaluating the Accuracy of Methods for Detecting Correlated Rates of Molecular and Morphological Evolution.Systematic biology · 2023Article
- Handling Logical Character Dependency in Phylogenetic Inference: Extensive Performance Testing of Assumptions and Solutions Using Simulated and Empirical Data.Systematic biology · 2023Article
- Cambrian radiation speciation events driven by sea level and redoxcline changes on the Siberian Craton.Science advances · 2023Article
- Developmental traits and life strategy of redlichiid trilobites.Biological reviews of the Cambridge Philosophical Society · 2023Article
- Proposed Early Cambrian cephalopods are chimaeras, the oldest known cephalopods are 30 m.y. younger.Communications biology · 2023Article
- Life cycle evolution in the trilobitesPeerJ · 2023Article
- Long-term clade-wide shifts in trilobite segment number and allocation during the Palaeozoic.Proceedings. Biological sciences · 2022Article
- Reassessing a cryptic history of early trilobite evolution.Communications biology · 2022Review
- Successive climate crises in the deep past drove the early evolution and radiation of reptiles.Science advances · 2022Article
- Review
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3 authors.
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Abstract
Trilobites are often considered exemplary for understanding the Cambrian explosion of animal life, due to their unsurpassed diversity and abundance. These biomineralized arthropods appear abruptly in the fossil record with an established diversity, phylogenetic disparity, and provincialism at the beginning of Cambrian Series 2 (∼521 Ma), suggesting a protracted but cryptic earlier history that possibly extends into the Precambrian. However, recent analyses indicate elevated rates of phenotypic and genomic evolution for arthropods during the early Cambrian, thereby shortening the phylogenetic fuse. Furthermore, comparatively little research has been devoted to understanding the duration of the Cambrian explosion, after which normal Phanerozoic evolutionary rates were established. We test these hypotheses by applying Bayesian tip-dating methods to a comprehensive dataset of Cambrian trilobites. We show that trilobites have a Cambrian origin, as supported by the trace fossil record and molecular clocks. Surprisingly, they exhibit constant evolutionary rates across the entire Cambrian, for all aspects of the preserved phenotype: discrete, meristic, and continuous morphological traits. Our data therefore provide robust, quantitative evidence that by the time the typical Cambrian fossil record begins (∼521 Ma), the Cambrian explosion had already largely concluded. This suggests that a modern-style marine biosphere had rapidly emerged during the latest Ediacaran and earliest Cambrian (∼20 million years), followed by broad-scale evolutionary stasis throughout the remainder of the Cambrian.
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