Dinosaurs disappeared from the Earth about 66 million years ago. But their extinction remained one of the greatest mysteries of science until this day. Eleven recognized dinosaur experts from across the globe reviewed the fossil evidence from North America and reached a consensus on how the dinosaurs were wiped out. The study appeared in the journal Biological Reviews.

Dinosaurs

The extinction of dinosaurs was abrupt

Scientists said that before the asteroid hit the Earth, there were a series of changes in the environment of our planet. Fluctuating temperatures, volcanic eruptions and changing sea levels were sculpting the Earth. These factors had created a perfect storm millions of years before the giant space rock pummeled the Earth. The storm weakened the food chain, resulting into low diversity among dinosaurs. Computer simulations showed that changes in the landscape and climate reduced the number of herbivorous giant beasts in North America, which formed the base of the food chain for dinosaurs.

And then, the asteroid hit the planet at a time when their ecosystems were vulnerable. Dr Steve Brusatte of the University of Edinburgh said that the giant asteroid strike happened at the “worst possible time.” The charismatic beasts were victims of colossal bad luck. The die-off was abrupt, not gradual as some scientists previously believed. It happened in a few thousands of years or even quicker, said Brusatte.

Dinosaurs might have survived if…

Had the asteroid hit a few million years earlier or a few million years later, the giant space rock might not have caused a dinopocalypse. That’s because herbivorous dinosaurs had a healthy population in North America a few million years before the catastrophe, which would have gained further diversity after going through the adverse climatic and environmental changes. But the asteroid came at a really bad time. Its impact would have triggered wildfires, temperature fluctuations, earthquakes, and tsunamis.

The big question that arises is why did dinosaurs disappear when many other creatures such as mammals and birds survived? Brusatte said many birds did go extinct. So, it would have been random. Though the study suggested that the dinosaur community was particularly susceptible when the space rock hit, there is no evidence suggesting that dinosaurs were doomed to extinction.