New findings challenge assumptions about dinosaur extinction
Seventy-five percent of life on Earth was destroyed after the asteroid impact in Chicxulub, which occurred 66 million years ago. Until now, scientists have proposed various theories about the cause of the extinction, including that of the dinosaurs. However, new research is now emerging.
Scientists most frequently referenced the theory related to the radical and prolonged cooling of Earth's climate. After the asteroid impact, a large amount of sulphur was supposed to be released into the atmosphere, negatively affecting temperature.
What really killed the dinosaurs?
It now appears, however, that these assumptions may have been exaggerated. The latest research is based on the analysis of drill cores taken from the asteroid impact site at Chicxulub. Scientists estimated from this how much sulphur was actually released into the atmosphere.
The number is impressive—about 74 billion tonnes of sulphur. Although this is a truly astronomical amount, it is five times lower than previously thought.
The Earth got colder, but not so much that life couldn't survive
It seems that 25% of Earth's species may have survived because the climate cooling wasn't as intense. The smaller amount of sulphur compared to previous assumptions means that the "cold and dark" atmosphere did not persist for as long. The return to normal climatic conditions turned out to be quicker than previously assumed.
Nonetheless, the release of sulphur into the atmosphere as a result of the asteroid impact contributed to the mass extinction of species. This happened because the impact occurred in an area where the rocks were rich in sulphates. In the latest research, scientists used a method of sulphur isotope analysis. They compared data with the Cretaceous-Paleogene boundary layer. The results of the study may also be useful to other scientists studying phenomena related to mass extinctions from 66 million years ago.
The new discovery also shows that life on Earth had a greater chance of survival than previously assumed, which may affect the way other mass extinction events are interpreted.
