A new study elaborated by a team of Stanford researchers argues that ocean deoxygenation led to a massive extinction, which took place more than 440 million years ago. It is theorized that the hostile anoxic conditions persisted for more than 3 million years, considerably longer in comparison to similar events that took place in the past.
The new data is quite essential for present times as it may offer a glimpse of the dire consequences that could surface due to declining oxygen levels that have been recorded across the world in both ocean and coastal waters, suggesting that a new extinction could be in the making.
According to one of the researchers who contributed the study, several questions related to anoxic conditions and the connections to die-offs have been answered, with a significant focus on the Late Ordovician Mass Extinction, which is one of the five massive extinctions that took place on Earth.
The study linked ocean deoxygenation to the massive extinction during the Late Ordovician era
During the start of the Late Ordovician period, the world was completely different. Most life forms could be found in the ocean, and the first plans were still closer to beaches than the land. A global cooling event initiated the first stage of a massive extinction event, with the second and large-scale stage being sparked by anoxia.
More than 85% of all the species which were found in the oceans at that time vanished due to hostile conditions. For this study, the researchers focused on the second stage of the extinction event.
A new model was created and used to track the way in which oxygen levels vary in metal isotopes that have been collected from particular sites. Thirty-one variables were taken into account by the researchers to ensure the accuracy of the measurements. The paper on ocean deoxygenation has been well-received in the scientific community and published in Nature Communications.