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Proterozoic and early Cambrian protists: evidence for accelerating evolutionary tempo.
Open accessAbstract
In rocks of late Paleoproterozoic and Mesoproterozoic age (ca. 1700-1000 million years ago), probable eukaryotic microfossils are widespread and well preserved, but assemblage and global diversities are low and turnover is slow. Near the Mesoproterozoic-Neoproterozoic boundary (1000 million years ago), red, green, and chromophytic algae diversified; molecular phylogenies suggest that this was part of a broader radiation of "higher" eukaryotic phyla. Observed diversity levels for protistan microfossils increased significantly at this time, as did turnover rates. Coincident with the Cambrian radiation of marine invertebrates, protistan microfossils again doubled in diversity and rates of turnover increased by an order of magnitude. Evidently, the Cambrian diversification of animals strongly influenced evolutionary rates, within clades already present in marine communities, implying an important role for ecology in fueling a Cambrian explosion that extends across kingdoms.
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Cited by
A Neoproterozoic Snowball Earth
Hoffman, P. F., Kaufman, A. J., Halverson, G. P., & Schrag, D. P. (1998) · Science · doi:10.1126/science.281.5381.1342 · Cited by 2,693
The snowball Earth hypothesis: testing the limits of global change
Hoffman, P. F., & Schrag, D. P. (2002) · Terra Nova · doi:10.1046/j.1365-3121.2002.00408.x · Cited by 1,585
Proterozoic Ocean Chemistry and Evolution: A Bioinorganic Bridge?
Anbar, A. D., & Knoll, A. H. (2002) · Science · doi:10.1126/science.1069651 · Cited by 1,191
Self-citationDalziel, I. W. D. (1997) · Geological Society of America Bulletin · doi:10.1130/0016-7606(1997)109<0016:onpgat>2.3.co;2 · Cited by 1,123
Estimating the timing of early eukaryotic diversification with multigene molecular clocks
Parfrey, L. W., Lahr, D. J. G., Knoll, A. H., & Katz, L. A. (2011) · Proceedings of the National Academy of Sciences · doi:10.1073/pnas.1110633108 · Cited by 899
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Metadata
- Authors
- Knoll, A. H.
- Venue
- Proceedings of the National Academy of Sciences
- Published
- 1994-07-19
- Volume
- 91
- Issue
- 15
- Pages
- 6743-6750
- ISSN
- 0027-8424 (ISSN-L)
- 1091-6490
- OpenAlex
- W2093852568
- Cited by
- 261
- References
- 0
- FWCI
- 4.17
- Type
- journal article
- Language
- en
- Open access
- green
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