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bioRxiv · 10.1101/241638

Stability, incumbency and ecological reorganizationafter the Permian-Triassic mass extinction

Roopnarine, P. D.·Weik, A.·Angielczyk, K. D.·Dineen, A. A.
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Abstract

The Permian-Triassic mass extinction (PTME) altered macroevolutionary land-scapes by removing incumbent biota. Here, using terrestrial paleocommunities of the Karoo Basin spanning the PTME, we show that a pre-extinction incumbent configuration of biotic interactions made significant ecological re-organizations or macroevolutionary innovations unlikely. The post-PTME ecosystem initially was more likely to be reorganized, but incumbency was re-established by the Middle Triassic. We argue that the stability of the pre-PTME ecosystem, its subsequent loss, and replacement, resulted from the in-fluence of community-level structure and dynamics on species evolution and survival.\n\nOne sentence summaryBiotic incumbency at the end of the Paleozoic, based on community functional organization, was destroyed by the Permian-Triassic mass extinction, allowing the development of novel community types.

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Roopnarine, P. D., Weik, A., Angielczyk, K. D., Dineen, A. A.. 2018-01-01. Stability, incumbency and ecological reorganizationafter the Permian-Triassic mass extinction. https://doi.org/10.1101/241638

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