Bioindicators of severe ocean acidification are absent from the end-Permian mass extinction

Abstract The role of ocean acidification in the end-Permian mass extinction is highly controversial with conflicting hypotheses relating to its timing and extent. Observations and experiments on living molluscs demonstrate that those inhabiting acidic settings exhibit characteristic morphological de...

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Bibliographic Details
Published in:Scientific Reports
Main Authors: William J. Foster, J. A. Hirtz, C. Farrell, M. Reistroffer, R. J. Twitchett, R. C. Martindale
Format: Article in Journal/Newspaper
Language:English
Published: Nature Portfolio 2022
Subjects:
R
Q
Online Access:https://doi.org/10.1038/s41598-022-04991-9
https://doaj.org/article/06b615ec4f6144a7ab57a3d8be7d10c2
Description
Summary:Abstract The role of ocean acidification in the end-Permian mass extinction is highly controversial with conflicting hypotheses relating to its timing and extent. Observations and experiments on living molluscs demonstrate that those inhabiting acidic settings exhibit characteristic morphological deformities and disordered shell ultrastructures. These deformities should be recognisable in the fossil record, and provide a robust palaeo-proxy for severe ocean acidification. Here, we use fossils of originally aragonitic invertebrates to test whether ocean acidification occurred during the Permian–Triassic transition. Our results show that we can reject a hypothesised worldwide basal Triassic ocean acidification event owing to the absence of deformities and repair marks on bivalves and gastropods from the Triassic Hindeodus parvus Conodont Zone. We could not, however, utilise this proxy to test the role of a hypothesised acidification event just prior to and/or during the mass extinction event. If ocean acidification did develop during the mass extinction event, then it most likely only occurred in the latest Permian, and was not severe enough to impact calcification.