Dinosaurs ARE THRIVED before an asteroid went extinct 66 million years ago

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Scientists have long speculated that dinosaurs were in decline before the catastrophic impact of asteroids wiped them out 66 million years ago – but a new study suggests prehistoric beasts may have thrived.

Previous work used fossil records to assess the diversity of dinosaurs, but researchers in the latest study explain how bones are preserved and other factors produce sampling bias.

Teams from the University of Bath and the Natural History Museum gathered a set of different dinosaur family trees and used statistical modeling to assess whether each of the major dinosaur groups was capable of producing new species at the time. .

This allowed them to examine the speciation rates of dinosaur families rather than counting the number of species in the family, revealing that certain groups, such as hadrosaurs and ceratopsians, were flourishing on Earth before extinction. massive.

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Scientists have long theorized that dinosaurs were in decline before the catastrophic impact of asteroids wiped them out 66 million years ago - but new study suggests prehistoric beasts may have thrived

Scientists have long theorized that dinosaurs were in decline before the catastrophic impact of asteroids wiped them out 66 million years ago – but new study suggests prehistoric beasts may have thrived

Principal author Joe Bonsor is undertaking his PhD jointly at the Milner Center for Evolution at the University of Bath and the Natural History Museum.

“Previous studies by others have used various methods to draw the conclusion that the dinosaurs would have died anyway, as they were in decline towards the end of the Cretaceous,” he said.

“ However, we show that if you expand the dataset to include more recent dinosaur family trees and a broader set of dinosaur types, the results don’t all point to this conclusion – in fact, only about the half of them do. ”

Bonsor and his team note that the reason other studies may go in the other direction is that gaps in the fossil record make it difficult to assess the diversity of dinosaurs.

Teams from the University of Bath and the Natural History Museum collected a set of different dinosaur family trees and used statistical modeling to assess whether each of the major dinosaur groups was capable of producing new species at the time.

Teams from the University of Bath and the Natural History Museum collected a set of different dinosaur family trees and used statistical modeling to assess whether each of the major dinosaur groups was capable of producing new species at the time.

This is due to the way bones are preserved as fossils, the accessibility of fossils in the rock for them to be found, and where paleontologists look for them.

In the study, the team used statistical methods to overcome these sampling biases, by examining the speciation rates of dinosaur families rather than counting the number of species belonging to the family.

“ The main point of our article is that it’s not as simple as looking at a few trees and making a decision – the inevitable large biases in the fossil record and lack of data can often show a decline in species, but this may not reflect the reality of the time, ”said Mr. Bonsor.

“ Our data does not currently show that they were in decline, in fact some groups such as hadrosaurs and ceratopsians were thriving and there is no evidence to suggest they would have died 66 million years ago. if the extinction event had not occurred. ”

There have been several studies that rely on the idea that dinosaurs thrived, while others suggest that they were in decline before the asteroid impact.

A 2016 study by a team from the Universities of Reading and Bristol found that the dinosaurs may have wobbled 50 million years before impact.

This allowed them to examine the speciation rates of dinosaur families rather than counting the number of species in the family, revealing that certain groups, such as hadrosaurs and ceratopsians (pictured), flourished on Earth before the mass extinction.

This allowed them to examine the speciation rates of dinosaur families rather than counting the number of species in the family, revealing that certain groups, such as hadrosaurs and ceratopsians (pictured), flourished on Earth before the ‘mass extinction.

They suggest that the lack of diversity is what ultimately led to their demise.

The group also used statistical analysis of the dinosaur family tree and compared them to the fossil record.

Just last year, a separate analysis from Imperial College London, University College London and the University of Bristol leaned towards the results of the recent study.

This group took into account speculations that the creatures were in decline due to the enormous pressures of climate change.

They looked at the climate changes associated with the distribution of dinosaur species in North America, where many dinosaur fossils have been found.

The team found that the habitats that could support them were much more widespread than originally thought, but these areas were less likely to preserve the fossils.

Many more fossils have been found in the western half of the newly formed Rocky Mountains, which created perfect conditions for dinosaur fossilization.

In contrast, the eastern half of the continent was much less conducive to fossilization.

This means that many more dinosaur fossils are found in the western half, and it is this fossil record that is often used to suggest that dinosaurs were in decline.

HOW DINOSAURS WERE EXTINCT 66 MILLION YEARS AGO

Dinosaurs ruled and dominated Earth around 66 million years ago, before they suddenly vanished.

The Cretaceous-Tertiary extinction event is the name given to this mass extinction.

It was believed for many years that climate change had destroyed the food chain of huge reptiles.

In the 1980s, paleontologists discovered a layer of iridium.

It is a rare element on Earth but found in large quantities in space.

When this was dated, it coincided precisely with when the dinosaurs disappeared from the fossil record.

A decade later, scientists discovered the enormous Chicxulub crater at the tip of Mexico’s Yucatán Peninsula, which dates back to the period in question.

Scientific consensus now says that these two factors are related and that they were probably both caused by a huge asteroid crashing into Earth.

With the size and speed of impact projected, the collision would have caused a huge shock wave and likely triggered seismic activity.

The fallout would have created plumes of ash that likely covered the entire planet and made it impossible for the dinosaurs to survive.

Other animals and plant species had a shorter time span between generations, which allowed them to survive.

There are several other theories about the cause of famous animals’ disappearance.

One of the earliest theories was that small mammals ate dinosaur eggs and another suggested that poisonous angiosperms (flowering plants) killed them.

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