Recent research suggests that volcanic eruptions, causing global cooling, significantly contributed to the dinosaurs’ extinction, challenging the long-held belief that a meteorite was the sole cause.
McGill researchers challenge the current understanding of dinosaur extinction by unearthing a link between volcanic eruptions and climate change.
What wiped out the dinosaurs? A meteorite plummeting to Earth is only part of the story, a new study suggests. Climate change triggered by massive volcanic eruptions may have ultimately set the stage for the dinosaur extinction, challenging the traditional narrative that a meteorite alone delivered the final blow to the ancient giants.
That’s according to a study published recently in Science Advances<em>Science Advances</em> is a peer-reviewed, open-access scientific journal that is published by the American Association for the Advancement of Science (AAAS). It was launched in 2015 and covers a wide range of topics in the natural sciences, including biology, chemistry, earth and environmental sciences, materials science, and physics.” data-gt-translate-attributes=”[{“attribute”:”data-cmtooltip”, “format”:”html”}]”>Science Advances, co-authored by Don Baker, a professor in McGill University’s Department of Earth and Planetary Sciences.
The research team delved into volcanic eruptions of the Deccan Traps—a vast and rugged plateau in Western India formed by molten lava. Erupting a staggering one million cubic kilometers of rock, it may have played a key role in cooling the global climate around 65 million years ago.
The work took researchers around the world, from hammering out rocks in the Deccan Traps to analyzing the samples in England and Sweden.
Volcanic Winters and Dinosaur Extinction
In the lab, the scientists estimated how much sulfur and fluorine were injected into the atmosphere by massive volcanic eruptions in the 200,000 years before the dinosaur extinction.
Remarkably, they found the sulfur release could have triggered a global drop in temperature around the world—a phenomenon known as a volcanic winter.
“Our research demonstrates that climatic conditions were almost certainly unstable, with repeated volcanic winters that could have lasted decades, prior to the extinction of the dinosaurs. This instability would have made life difficult for all plants and animals and set the stage for the dinosaur extinction event. Thus our work helps explain this significant extinction event that led to the rise of mammals and the evolution of our speciesA species is a group of living organisms that share a set of common characteristics and are able to breed and produce fertile offspring. The concept of a species is important in biology as it is used to classify and organize the diversity of life. There are different ways to define a species, but the most widely accepted one is the biological species concept, which defines a species as a group of organisms that can interbreed and produce viable offspring in nature. This definition is widely used in evolutionary biology and ecology to identify and classify living organisms.” data-gt-translate-attributes=”[{“attribute”:”data-cmtooltip”, “format”:”html”}]”>species,” said Prof. Don Baker.
Innovative Research Techniques
Uncovering clues within ancient rock samples was no small feat. In fact, a new technique developed at McGill helped decode the volcanic history.
The technique for estimating sulfur and fluorine releases–a complex combination of chemistry and experiments–is a bit like cooking pasta.
“Imagine making pasta at home. You boil the water, add salt, and then the pasta. Some of the salt from the water goes into the pasta, but not much of it,” explains Baker.
Similarly, some elements become trapped in minerals as they cool following a volcanic eruption. Just as you could calculate salt concentrations in the water that cooked the pasta from analyzing salt in the pasta itself, the new technique allowed scientists to measure sulfur and fluorine in rock samples. With this information, the scientists could calculate the amount of these gases released during the eruptions.
The study involved researchers from Italy, Norway, Sweden, the UK, the United States and Canada.
Their findings mark a step forward in piecing together Earth’s ancient secrets and pave the way for a more informed approach to our own changing climate.
Reference: “Recurring volcanic winters during the latest CretaceousThe Cretaceous is a geological period that lasted from about 145 to 66 million years ago. It is the third and final period of the Mesozoic Era. It ended with the Cretaceous–Paleogene extinction event.” data-gt-translate-attributes=”[{“attribute”:”data-cmtooltip”, “format”:”html”}]”>Cretaceous: Sulfur and fluorine budgets of Deccan Traps lavas” by Sara Callegaro, Don R. Baker, Paul R. Renne, Leone Melluso, Kalotina Geraki, Martin J. Whitehouse, Angelo De Min and Andrea Marzoli, 4 October 2023, Science Advances.
DOI: 10.1126/sciadv.adg8284
Source: SciTechDaily
