Dominant pyrite morphologies and in situ nanoSIMS sedimentary pyrite δ34S [IMAGE: NANJING INSTITUTE OF GEOLOGY AND PALAEONTOLOGY, CHINESE ACADEMY OF SCIENCES]

A study has revealed that the oxygen content of the deep sea surged 600 million years ago, laying the foundations for the emergence of multicellular organisms.

Paleontologists at the Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, worked with researchers from the United States and France. Their findings were published in the journal Geology.

Oxygen is essential for the survival of life. There is enough oxygen in today's oceans to meet the needs of plants and animals, but this was not always the case, according to Wang Wei, a researcher with the institute.

It is generally believed that modern oceans began to form 450 million years ago. Before that, the deep-sea environment cycled between oxidation and hypoxia, said Wang, who was also the leader of the research project.

The research team studied deep-sea core samples dating back 600 million years and found the oxygen content increased significantly during this period due to large-scale oxidation, making the period a key chapter in the evolution of life on Earth.

The conclusion was also proved by the discovery of fossils containing multicellular organisms, Wang added.

Source: Xinhua