What really ended dinosaurs? A fresh scientific study suggests that an asteroid strike was not the sole factor in the dinosaurs’ demise. Volcanic activity may have contributed significantly by shaping the climate, challenging the long-standing belief that a meteorite alone sealed their fate.
This new evidence appears in a study published in Science Advances. The research, led by scholars from McGill University in Canada, sheds bright light on this enduring mystery and points to a more nuanced extinction scenario.
The investigation centers on the Deccan Traps, a vast plateau in western India formed by massive volcanic eruptions. Estimates suggest that about one million cubic kilometers of molten rock erupted, a cataclysm that could have cooled the global climate around 65 million years ago and influenced the mass extinction process.
Massive volcanic activity changed the atmosphere in ways that likely altered global temperatures and environmental conditions for extended periods, underscoring the role of climate stress in the dinosaur decline.
Scientists have calculated in the laboratory how much sulfur and fluorine were released into the atmosphere by these large eruptions that occurred roughly 200,000 years before the extinction event. The results are striking: sulfur emissions could have driven a drop in global temperatures, creating a volcanic winter scenario that persisted across multiple decades.
The researchers emphasize that climate conditions in that era were probably unstable, with repeated volcanic winters that lasted for decades. Such prolonged instability would have made life difficult for plants and animals alike and helped pave the way for the dinosaurs’ disappearance. The study thus contributes to a fuller explanation of the major extinction event that eventually allowed mammals and, much later, humans to evolve.
As for the discovery process itself, the team employed a new technique developed at McGill to decipher volcanic history from ancient rock samples. The method combines elements of chemistry and experimental science to estimate sulfur and fluorine emissions with a level of precision that echoes everyday cooking analogies.
Picture making pasta at home. Water boils, salt is added, and pasta is introduced. Some salt leaches into the pasta, but not all. Similarly, as volcanic material cools, some elements become trapped within minerals. By analyzing these mineral-bound salts, scientists can back-calculate the amount of sulfur and fluoride released during eruptions, turning rock into a meteorologically meaningful record of past volcanic activity.
The geographic focus of the study spans several nations and institutions, with involvement from researchers in Italy, Norway, Sweden, England, the United States, and Canada. Their collaborative effort marks progress in the ongoing quest to reconstruct Earth’s ancient climate and contributes to our understanding of contemporary climate change in a long-term context.
Reference work: DOI: 10.1126/sciadv.adg8284
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