Deep-water corals indicate the Red Sea survived the last glacial lowstand

Creators: Chakraborty, Morgan I.¹; Sharifi, Arash^{1, 2}; Benzoni, Francesca³; Tissot, François L. H.⁴; Pourmand, Ali¹; Taviani, Marco^{5, 6}; Howes, Bolton¹; Swart, Peter K.¹; Lu, Choajin¹; Rodrigue, Mattie⁷; Purkis, Sam J.¹

1. University of Miami
2. Beta Analytic Inc., Isobar Science, Miami, FL, 33155
3. King Abdullah University of Science and Technology
4. California Institute of Technology
5. Institute of Marine Science
6. Stazione Zoologica Anton Dohrn
7. OceanX, New York, NY, 10018

Abstract

The Red Sea, a nascent ocean basin connected to the Indian Ocean via a shallow strait, is assumed to have experienced significant environmental changes during the last glacial period due to a sea-level drop likely exceeding 110 m. This study investigates the hypothesis that hydrodynamic restriction led to severe ecological impacts, including basin-wide extinction due to elevated salinity followed by a short time of oxygen depletion. Uranium–Thorium dating of deep-water corals (DWCs) from 26 northern Red Sea sites reveals coral growth during and after the Last Glacial sea-level lowstand, indicating tolerable seawater chemistry. Additional geochemical data show no significant difference in Red Sea chemistry or temperature between the Latest Pleistocene and Holocene. A meta-analysis of 27 deep-sea cores reveals that while planktonic foraminifera experienced local extinction, other microfossil groups seemingly persisted. These findings suggest that the Red Sea survived the last sea-level lowstand, challenging the paradigm of a complete ecological collapse and providing insights into the resilience of marine ecosystems.

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Acknowledgement

We owe a debt of gratitude to our Saudi Arabian partners, NEOM, and to Richard Bush, Deborah Colbourne, Jennifer Munro, and Abdulqader Khamis for their support. We are also indebted to OceanX and the crew of OceanXplorer for their operational and logistical assistance. Special thanks to Andrew Craig, Olaf Dieckoff, Ewan Bason, and Kate von Krusenstiern for data acquisition, sample collection, and support of scientific operations aboard OceanXplorer. We also thank OceanX Media for documenting and communicating this work to the public. Gratitude is extended to Mike Ackerman for assistance with sample preparation. We sincerely thank the three anonymous reviewers for their thoughtful and constructive feedback which improved the clarity and depth of our manuscript. This is Ismar-CNR, Bologna, scientific contribution no. 2095.

Funding

This study was funded by NEOM Agreement No: SRA-ENV-2023-001/AWD-008854 to the University of Miami.

Supplemental Material

Appendix 01 (PDF)

Dataset S01 (XLSX)

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