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Microbial carbonates commonly flourished accompanied by mass extinction events.The end-Devonian(Hangenberg)mass extinction event is a first-order mass extinction in the scale of the Big Five extinctions.However,to date,it is still unclear whether global microbial carbonate proliferation occurred after the Hangenberg event.The earliest known Carboniferous stromatolites on tidal flats are described from intertidal environments of the lowermost Tournaisian(Qianheishan Formation)in northwestern China.With the other early Tournaisian microbe-dominated bioconstructions extensively distributed on shelves,the Qianheishan stromatolites imply that microbial carbonate proliferation may have occurred after the Hangenberg extinction.This is confirmed by a quantitative analysis of abundance of microbedominated bioconstructions through the Famennian and early Tournaisian,which shows that they were globally distributed(between 40° latitude on both sides of the palaeoequator)and that their abundance increased distinctly in the early Tournaisian compared to the latest Devonian(Strunian).Comparison of variations in the relative abundance of skeleton-versus microbe-dominated bioconstructions across the Hangenberg and Big Five extinctions suggests that changes in abundance of skeletal bioconstructors may play a first-order control on microbial carbonate proliferation during extinction transitions and that microbial proliferation is not a general necessary feature after mass extinctions.