Perhaps it’s no secret to anyone that in the scientificdisputes about what caused the death of dinosaurs 65 million years ago do not cease in the community. So, just recently we told you about the results of a study according to which dinosaurs could well have died before the fall of the asteroid Chiksulub. The fact is that due to large-scale volcanic activity in the Earth's atmosphere, a very high concentration of mercury was observed. However, the findings of the new study seem to finally dot all the “ands”, putting an end to years of debate. We tell what scientists managed to find out.
What happened on Earth 65 million years ago?
About 65 million years ago, an asteroid with a diameter10 km hit the Yucatan Peninsula in Mexico and killed most species on our planet. As a result of the fall into the atmosphere, a large amount of molten material and gases was released, which caused acid rain, acidification of the surface waters of the oceans and sudden warming, which lasted for years. Then came the nuclear winter, which lasted decades.
However, scientists did not always agree thatit was the asteroid that caused the mass death of dinosaurs. Part of the research community believed that intense volcanic activity also contributed to the extinction of wildlife. Thus, recently, experts found that volcanism at the end of the Cretaceous in time coincided with mass extinction. Indeed, two events of planetary importance, which more or less coincide in time, gave rise to a discussion about which of the two events caused the disappearance: whether volcanism could weaken ecosystems, or the meteorite served as the reason.
It is interesting: Dinosaurs could destroy the car with teeth.
Why did dinosaurs die?
According to a recent study, whichpublished in the journal Science, volcanic activity did not play a direct role in the mass extinction of dinosaurs. According to a team led by scientists from Yale University (USA), the only reason for the death of wildlife was an asteroid. According to the researchers, volcanoes can indeed cause mass extinction, as they emit a lot of gases, such as sulfur oxide and carbon dioxide, which can change the climate and oxidize the planet. However, volcanic activity and the associated warming occurred before and after the impact, and not during extinction.
As the results showed, with the disappearancegiant dinosaurs only coincided with the fall of the asteroid. Subsequently, new volcanic phases slowed the restoration of ecosystems. Volcanic activity in the Cretaceous caused a gradual global warming of about 2 ° C, but not a mass extinction. To arrive at these conclusions, the researchers analyzed the data collected from the oceans and combined the records of the climatic, biotic and carbon cycles obtained from sediments and marine fossils, such as the teeth and shells of mollusks, and compared them with different scenarios of volcanic eruptions and their effects. As a result, the researchers were able to create a detailed reconstruction of the global temperature of that period.
Thus, the researchers demonstrate that most of the gas ejection occurred long before the impact of the asteroid, and that Chiksulub caused the extinction of the dinosaurs. Well, the secret is revealed!