Theory and classification of mass extinction causation  

作　　者：Thomas J.Algeo Jun Shen 

机构地区：[1]State Key Laboratory of Biogeology and Environmental Geology,China University of Geosciences—Wuhan,Wuhan430074,China [2]State Key Laboratory of Geological Processes and Mineral Resources,China University of Geosciences—Wuhan,Wuhan430074,China [3]Department of Geosciences,University of Cincinnati,Cincinnati,OH45221,USA

出　　处：《National Science Review》2024年第1期11-31,共21页国家科学评论（英文版）

基　　金：Research of J.S. was supported by the National Natural Science Foundation of China (42072037 and 92055201);the 111Project of the National Bureau of Foreign Experts and the Ministry of Education of China (BP0820004)。

摘　　要：Theory regarding the causation of mass extinctions is in need of systematization, which is the focus of this contribution. Every mass extinction has both an ultimate cause, i.e. the trigger that leads to various climato-environmental changes, and one or more proximate cause(s), i.e. the specific climato-environmental changes that result in elevated biotic mortality. With regard to ultimate causes, strong cases can be made that bolide(i.e. meteor) impacts, large igneous province(LIP) eruptions and bioevolutionary events have each triggered one or more of the Phanerozoic Big Five mass extinctions, and that tectono-oceanic changes have triggered some second-order extinction events. Apart from bolide impacts, other astronomical triggers(e.g.solar flares, gamma bursts and supernova explosions) remain entirely in the realm of speculation. With regard to proximate mechanisms, most extinctions are related to either carbon-release or carbon-burial processes, the former being associated with climatic warming, ocean acidification, reduced marine productivity and lower carbonate δ^(13)C values, and the latter with climatic cooling, increased marine productivity and higher carbonate δ^(13)C values. Environmental parameters such as marine redox conditions and terrestrial weathering intensity do not show consistent relationships with carbon-cycle changes.In this context, mass extinction causation can be usefully classified using a matrix of ultimate and proximate factors. Among the Big Five mass extinctions, the end-Cretaceous biocrisis is an example of a bolide-triggered carbon-release event, the end-Permian and end-Triassic biocrises are examples of LIP-triggered carbon-release events, and the Late Ordovician and Late Devonian biocrises are examples of bioevolution-triggered carbon-burial events. Whereas the bolide-impact and LIP-eruption mechanisms appear to invariably cause carbon release, bioevolutionary triggers can result in variable carbon-cycle changes, e.g. carbon burial during the Late Ordovician and Late Devonian

关 键 词：biocrisis ultimate cause proximate cause BOLIDE large igneous province bioevolutionary event 

分 类 号：Q111.7[生物学—普通生物学]