Oceanographic and evolutionary inferences based on fossil assemblages can be obscured by age offsets among co‐occurring shells (i.e., time averaging). To identify the contributions of sedimentation, mixing, durability, and production to within‐ and between‐species age offsets, we analyze downcore changes in the age‐frequency distributions of two bivalves on the California shelf. Within‐species age offsets are ~50–2,000 years for
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Understanding how time averaging changes during burial is essential for using Holocene and Anthropocene cores to analyze ecosystem change, given the many ways in which time averaging affects biodiversity measures. Here, we use transition-rate matrices to explore how the extent of time averaging changes downcore as shells transit through a taphonomically complex mixed layer into permanently buried historical layers: this is a null model, without any temporal changes in rates of sedimentation or bioturbation, to contrast with downcore patterns that might be produced by human activity. Assuming stochastic burial and exhumation movements of shells
- Award ID(s):
- 1855381
- NSF-PAR ID:
- 10467938
- Publisher / Repository:
- Cambridge University Press
- Date Published:
- Journal Name:
- Paleobiology
- Volume:
- 49
- Issue:
- 3
- ISSN:
- 0094-8373
- Page Range / eLocation ID:
- 527 to 562
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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