Early animal evolution and highly oxygenated seafloor niches hosted by microbial mats.

ABSTRACT: The earliest unambiguous evidence for animals is represented by various trace fossils in the latest Ediacaran Period (550-541 Ma), suggesting that the earliest animals lived on or even penetrated into the seafloor. Yet, the O₂ fugacity at the sediment-water interface (SWI) for the earliest animal proliferation is poorly defined. The preferential colonization of seafloor as a first step in animal evolution is also unusual. In order to understand the environmental background, we employed a new proxy, carbonate associated ferrous iron (Fe_carb), to quantify the seafloor oxygenation. Fe_carb of the latest Ediacaran Shibantan limestone in South China, which yields abundant animal traces, ranges from 2.27 to 85.43 ppm, corresponding to the seafloor O₂ fu

SUBMITTER: Ding W 

PROVIDER: S-EPMC6754419 | biostudies-literature | 2019 Sep

REPOSITORIES: biostudies-literature