The timing and pattern of biotic recovery following the end-Permian mass extinction

Abstract

The aftermath of the great end-Permian period mass extinction 252 Myr ago shows how life can recover from the loss of >90% species globally. The crisis was triggered by a number of physical environmental shocks (global warming, acid rain, ocean acidification and ocean anoxia), and some of these were repeated over the next 5–6 Myr. Ammonoids and some other groups diversified rapidly, within 1–3 Myr, but extinctions continued through the Early Triassic period. Triassic ecosystems were rebuilt stepwise from low to high trophic levels through the Early to Middle Triassic, and a stable, complex ecosystem did not re-emerge until the beginning of the Middle Triassic, 8–9 Myr after the crisis. A positive aspect of the recovery was the emergence of entirely new groups, such as marine reptiles and decapod crustaceans, as well as new tetrapods on land, including — eventually — dinosaurs. The stepwise recovery of life in the Triassic could have been delayed either by biotic drivers (complex multispecies interactions) or physical perturbations, or a combination of both. This is an example of the wider debate about the relative roles of intrinsic and extrinsic drivers of large-scale evolution.

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Figure 1: Environmental changes and biodiversity variations from the latest Permian to Middle Triassic.
Figure 2: Outline trophic pyramid of a fossilized marine ecosystem in the Permian or Triassic.
Figure 3: Reconstructed marine ecosystems before and after the end-Permian mass extinction in south China.
Figure 4: Stepwise rebuilding pattern of marine ecosystems from low to top trophic levels in the aftermath of the EPME.

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Acknowledgements

Thanks to John Sibbick for the spectacular artwork in Fig. 3, and to Ricard Solé for supplying information for the figure in Box 2. This work was funded by ARC Discovery Grant DP0770938 to Z.Q.C., NSFC grant 40830212 to J. Tong, the 111 program of China (grant No. B08030) to S. Xie, China Geological Survey Projects (No. 1212010610211, 1212011140051) and NERC grant NE/C518973/1 to M.J.B. This is a contribution to IGCP572.

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Correspondence to Michael J. Benton.

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Chen, Z., Benton, M. The timing and pattern of biotic recovery following the end-Permian mass extinction. Nature Geosci 5, 375–383 (2012). https://doi.org/10.1038/ngeo1475

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