The Cambrian Explosion of Life is known as a major unsolved mystery in paleontology and geology. For some time, its cause has been a hot topic in the academic community.

The reporter learned from the University of Science and Technology of China that recently, Wei Wei, an associate researcher, Dong Linhui, a doctoral student, and Huang Fang, a professor at the university, found that the removal of sulfides and barium ions in seawater that were toxic to early animals led to the Cambrian explosion of life. This discovery provides new insights into the feedback mechanism between early Cambrian ocean oxidation and the explosion of life.

According to reports, there was an explosion of life in the early Cambrian period. Traditionally, it is believed that this may be related to the oxidation of the ocean. However, related studies have shown that early animals did not have a high demand for oxygen. Some people even believe that ocean oxidation was the result of the Cambrian explosion of life rather than the cause. It can be seen that the feedback mechanism between the redox changes in the ocean in the early Cambrian period and the explosion of life is still unclear and needs further exploration.

Schematic diagram of the relationship between the removal of ocean barium ions and the Cambrian explosion of life. Photo provided by the interviewee

Recently, Wei Wei and others found through the barium isotope data of the metal-rich shales of the Cambrian in the Yangtze Plate that the gradual oxidation of the ocean during the Ediacaran-Cambrian transition increased the sulfate concentration, resulting in the removal of a large number of previously accumulated dissolved barium ions in the form of barite. High concentrations of barium in water bodies inhibit the survival rate of aquatic animals. Therefore, the removal of sulfides and barium ions that are toxic to animals improved the habitability of the ocean and promoted the Cambrian explosion of life.

The relevant research results were recently published in the academic journal National Science Review.