At last, the truth revealed that the age-old myth of volcanic eruptions was not the reason but the asteroid impact that triggered earth to be unsuitable for dinosaurs. Scientists have conducted meticulous research and studies for many years. They found out recently what exactly caused a mass extinction event 66 million years ago that killed most of the dinosaurs unsuitable for this earth.
Previously, studies blamed this extinction because of volcanic eruptions. But recent studies confirmed that an asteroid impact was the foremost reason behind the extinction of the dinosaur’s era.
Causes of global mass extinctions
We believe asteroids to be large, rocky bodies that orbit the sun. The area ranges from a few hundreds of meters in diameter. We know the fragment of an asteroid that survives the landing on earth as Meteorite.
This city-size asteroid that slammed into Earth would have plunged the planet into a drastic winter. They believed that it lasted for years, creating a world unsuitable for the dinosaurs to live in.
We can still see the evidence as a crater that is largely buried on the seafloor off the coast of Mexico. Studies conducted, says that it is exactly the same age as the extinction of the dinosaurs, and we can track it in the rock record all around the world.
The impact site, known as the Chicxulub crater, is centered on the Yucatan Peninsula in Mexico. We believe the asteroid to be between 10 to 15 kilometers wide, but the velocity of the collision caused the creation that was much larger than carter, believed to be 150 kilometers in diameter and also the second-largest crater on the planet.
This crash threw tremendous amounts of debris into the air and caused massive tidal waves to wash over parts of American continents. We see evidence of substantial fires from that point of history.
Global Climatic Change
The study also revealed that the asteroid strike released particles and gases high into the atmosphere, blocking out the sun for years and causing permanent winters.
The recent study has also poured out more than that on the theory that massive volcanic eruptions in the Deccan Traps, an area believed to be in modern-day India, played a significant role in their demise.
It sent soot traveling throughout the world. Although this impact didn’t completely block out the sun, it substantially reduced the amount of light that reached the earth’s surface. This influenced plant growth, causing the ecosystem to collapse. This brought a reduction in plant life that had an enormous impact on herbivores, which meant that carnivores would also have suffered from having less food available.
All living things got affected both on land and in the ocean, as breeding seasons would have been shorter and also conditions harsher.
During that time around 75% of Earth’s animals, including dinosaurs, suddenly died out at the same point in time.
Surviving Asteroid Impact
The research also shows that the massive volcanism could also have helped life recover from the asteroid strike in the long term.
Although volcanoes release Sun-blocking gases and particles, they also release CO2, a greenhouse emission. In the brief term after an eruption, the Sun-blockers have a larger effect, causing a ‘volcanic winter’. However, in the long run, these particles and gases drop out of the atmosphere, while CO2 stays around and builds up, warming the earth.
After the initial drastic global winter caused by the asteroid, volcanic warming helped to restore many habitats, helping recent life that developed after the disaster to thriving.
Fresh evidence suggests that the volcanic eruptions happening around the same time might have reduced the effects on the environment caused by the impact. Especially in quickening the rise of temperatures after the winter impact.
Earlier, the major culprit was volcanic eruptions, but the recent study is contrary. This warming helped to boost the survival and recovery of the animals and plants that were made through extinction, with many groups expanding in its immediate aftermath, including birds and mammals.
It can’t be blamed solely on the asteroid. Before the crash landing, the earth was experiencing climate change, and that was making it harder for life on the planet.
Present Central India, there was substantial volcanic activity unrelated to an asteroid impact, and that was creating a problem of its own. That lava outcrop is known as Deccan Traps.
For almost two million years an enormous amount of volcanic activity was going on, emitting gases into the atmosphere and subsequently having a major impact on the global climate.
Alternatively, the continent was splitting and drifting around apart from each other, resulting in bigger oceans that changed the ocean and atmosphere patterns around the world. This had a stronger effect on climate and vegetation.
So, it leaves us with basically the seeds of what we have today. Almost all the animal groups that are alive today were before the asteroid impact, and they all suffered some level of extinction. Alternatively, that led to new breeds of modern animals.
If it was not for the asteroid, dinosaurs might have survived a little longer. Despite modern birds, mammals, and reptiles starting to develop, there is also a chance that they may not have dominated as they once did.