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Updated: May 26, 2026
07:32
Monitoring Pedogenic Inorganic Carbon Accumulation Due to Weathering of Amended Silicate Minerals in Agricultural Soils.
Published on: June 4, 2021
A timeline for terrestrialization: consequences for the carbon cycle in the Palaeozoic
Paul Kenrick1, Charles H Wellman, Harald Schneider
1Department of Palaeontology, The Natural History Museum, Cromwell Road, London SW7 5BD, UK. p.kenrick@nhm.ac.uk
Summary
The origin of land plants and animals significantly impacts Earth's carbon cycle. Fossil and molecular data conflict, suggesting land life may have originated earlier than fossils indicate.
Area of Science:
- Geochemistry
- Paleontology
- Evolutionary Biology
Background:
- The geochemical carbon cycle is heavily influenced by terrestrial life, impacting carbon sequestration and rock weathering.
- Understanding the origin of land plants and animals is vital for comprehending the carbon cycle's evolution and its effects on Earth systems.
Purpose of the Study:
- To compare fossil evidence with molecular phylogenetics (timetrees) to resolve discrepancies in the timing of early land life.
- To investigate biases in the fossil record that may obscure the true origin of terrestrial ecosystems.
Main Methods:
- Comparative analysis of fossil records for plants and arthropods.
- Calibration of molecular phylogenetic trees (timetrees) for living plants and arthropods.
- Identification and analysis of biases within the fossil record, particularly facies changes.
Main Results:
- Conflicting timelines emerge when comparing fossil data with molecular timetrees regarding the origin and diversification of land life.
- Fossil record biases, especially facies changes, likely mask an earlier origin of terrestrial life than currently evidenced.
- Discrepancies highlight challenges in accurately dating the emergence of key terrestrial organisms and systems.
Conclusions:
- The timing of early land plant and animal evolution is complex and subject to interpretation based on data source.
- Fossil data may underestimate the antiquity of terrestrial life due to preservation and depositional biases.
- A revised understanding of early land life's origin has significant implications for Early Palaeozoic carbon cycle dynamics.
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