correlation or causality

https://phys.org/news/2022-11-decrease-crucial-element-ancient-mass.html

Researchers report that the concentration of molybdenum fell before a mass extinction occured (estimated 183 million years ago). However that decline preceded the extinction by about one million years. So could it be the cause?

@Ponderable

„The decrease in molybdenum also implies a massive increase in organic carbon burial in the ocean that may have been several times larger than previous calculations. Those calculations were based on estimations of carbon dioxide released from volcanic activity, implying that carbon dioxide release from volcanoes was actually much higher, which would be necessary to balance global carbon reservoirs.

Just like 183 million years ago, more and more carbon dioxide is being added to the Earth system today, which could reduce marine trace metals such as molybdenum that many organisms rely on for survival as the oceans lose oxygen and bury more organic carbon. „


It would appear that the level of molybdenum is a knock-on effect of volcanic activity and a change in the ratio of oxygen to carbon in the oceans. Hence, not a cause.