Introduction

The end-Permian mass extinction (EPME) was marked by the loss of up to 81% of marine species in a short time interval of 61 ± 48 kyr and is considered the most severe biocrisis in Earth history1,2,3. Unraveling the mechanisms for this biocrisis is crucial for understanding the relationships between environmental changes and biological macroevolution. Numerous studies suggest that widespread marine anoxia likely drove the marine mass extinction4,5,6,7. A shift toward more dysoxic conditions at the EPME has been implicated in most global oceanic settings based on biomarkers8, iron speciation9,Full size image