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Macroscopic organisms lived in the Yangtze Sea of South China during the Late Doushantuo period of the Ediacaran.The results of the specimen collections and statistics within each meter show that the macroscopic biota from the Ediacaran Doushantuo Formation in northeast Guizhou,South China,can be subdivided into Globusphyton,Cucullus,Sectoralga-Longifuniculum, Beltanelliformis,and Baculiphyca-Gesinella paleo-communities.The paleo-community evolution indicates the relationship not only between biota and environment,but also between metaphytes and metazoans.From the Globusphyton paleo-community,through to the Sectoralga-Longifuniculum paleo-community,to the Cucullus paleo-community,the increase in the abundance and diversity of metaphytes(especially the branching macroalgae)and metazoans implies that the oxygen content in the seawater increased gradually.Both the Beltanelliformis and Baculiphyca-Gesinella paleo-communities could be related to a deteriorated environment and fragile ecosystem.The emergence,abundance,and diversity of macroscopic metaphytes,which were closely connected with the environmental microchanges,accelerated the process,improving the environment and increasing oxygen,and established an important platform for the development of macroscopic metazoans.
Macroscopic organisms lived in the Yangtze Sea of South China during the Late Doushantuo period of the Ediacaran. The results of the specimen collections and statistics within each meter show that the macroscopic biota from the Ediacaran Doushantuo Formation in northeast Guizhou, South China, can be subdivided into Globusphyton, Cucullus, Sectoralga-Longifuniculum, Beltanelliformis, and Baculiphyca-Gesinella paleo-communities. The paleo-community evolution indicates the relationship not only between biota and environment, but also between metaphytes and metazoans. From the Globusphyton paleo-community, through to the Sectoralga-Longifuniculum paleo-community, to the Cucullus paleo-community, the increase in the abundance and diversity of metaphytes (especially the branching macroalgae) and metazoans implies that the oxygen content in the seawater increased gradually.Both the Beltanelliformis and Baculiphyca-Gesinella paleo-communities could be related to a deteriorated environment and fragile ecosys tem. emergence, abundance, and diversity of macroscopic metaphytes, which were closely connected with the environmental microchanges, accelerated the process, improving the environment and increasing oxygen, and established an important platform for the development of macroscopic metazoans.