 The Ediacaran period, 635 to 539 million years ago, saw the emergence and diversification of complex metazoans, which were likely linked to ocean redox changes. However, the exact mechanisms behind these changes remain unclear. New research suggests that photiczone euxinia, PZE, or the presence of sulfuric acid in the sunlit layer of the ocean, had been responsible for the redox evolution in the Ediacaran ocean. This process was triggered by increased availability of sulfates and nutrients from a transiently oxygenated ocean, but it could have also had negative effects such as promoting anoxygenic photosynthesis and limiting the habitable space for eukaryotic organisms. As a result, this may have contributed to the limited expansion of macroscopic oxygen-demanding animals and the rise of oxygen levels in the atmosphere. This article was authored by Wang Xing and Wenju, Swapen Kei Sofu, and others. We are article.tv, links in the description below.