It is known that the era of the dinosaurs ended when a giant asteroid collided with Earth 66 million years ago.
But where there is less scientific consensus is whether the creatures actually degenerated before the Chicxulub space rock wiped out more than 75 percent of the planet’s species.
One recent study suggested that climate change might be to blame for their struggles – but new research contradicts this and provides the strongest evidence yet that dinosaurs were in fact thriving shortly before they killed off.
An international team of experts from the UK and Spain They analyzed 1,600 fossil records from North America to reach their conclusion.
The results: Dinosaurs were in their prime and not in decline when an asteroid slammed into Earth 66 million years ago, a new study finds. Triceratops is depicted bothering the primitive cousins of the marsupial mammals in the brush
Or was climate change more to blame?
Researchers from the Chinese Academy of Sciences studied more than 1,000 fossilized dinosaur eggs and eggshells, and claimed that the animals were already in a state of decline when the asteroid hit – possibly as a result of climate change.
“Our results support a long-term decline in global dinosaur biodiversity 66 million years ago, which likely paved the way for the mass extinction of non-Cretaceous dinosaurs at the end of the Cretaceous period,” the team wrote in their study published in PNAS in September.
Most of the data on the last days of dinosaurs comes from North America, but for this study, the researchers turned to records in China.
They wanted to determine why dinosaurs other than birds, including Tyrannosaurus rex and Triceratops, became extinct – while other mammals and species such as turtles and crocodiles survived.
To do this, the experts Modeling the food chains and ecological habitats of terrestrial and freshwater animals during the last several million years of the Cretaceous period, as well as the first few million years of the Paleogene after the asteroid impact.
They discovered that prior to the impact, mammals were diversifying their diets, adapting to their environments and becoming a more important part of ecosystems with the onset of the Cretaceous period.
On the other hand, dinosaurs already ruled the world and were in their prime, so they had no reason to adapt in the same way. They actually succeeded in doing this to get to where they were.
This discovery indicates that mammals not only took advantage of the death of the dinosaurs, but were already creating their own advantages through diversification prior to the asteroid impact.
This evolution meant they had a more varied diet and were better prepared for subtle shifts in climate, so they were better prepared than dinosaurs to deal with. Cause the sudden destruction of the earth.
Study author Professor Steve Brusatte, from the University of Edinburgh, said the researchers found that dinosaurs were robust, with stable ecosystems, until an asteroid suddenly killed them.
“Meanwhile, mammals were diversifying their diet, ecology and behaviors while the dinosaurs were still alive,” he said.
So it wasn’t simply that mammals benefited from the death of the dinosaurs, but that they were achieving their own advantages, which ecologically prepped them to survive extinction and move into places left vacant by the dead dinosaurs.
While previous studies have shown that a large group of dinosaurs was on Earth just before the asteroid hit, until now it is not clear whether they were in their prime or actually in decline.
Another earlier study, published in 2016, claimed that dinosaurs were already dwindling 50 million years before Chicxulub.
The University of Reading researchers suggested that the creatures were in a state of long-term decline because they could not adapt to the ways in which the Earth had changed.
Show their analysis Giant, long-necked sauropod dinosaurs regressed faster, while theropods, which included T.Rex,was in a more gradual state of deterioration.
But the new study disputes that and insists that dinosaurs were thriving until the asteroid changed the environmental rules at the time.
Lead author Alfio Alessandro Chiarenza, from the University of Vigo, said: ‘It appears that the stable environment of the last dinosaurs really hampered their survival in the aftermath of the asteroid impact, which abruptly changed the ecological rules of the time.
Researchers wanted to determine why non-avian dinosaurs, including Tyrannosaurus rex and Triceratops, went extinct – while other mammals and species such as turtles and crocodiles survived.
Researchers from the Chinese Academy of Sciences studied more than 1,000 fossilized dinosaur eggs and eggshells, and claimed in a paper published in September that the animals were already in decline when the asteroid hit. This contradicts the latest research
Conversely, some birds, mammals, crocodiles, and turtles were better adapted to the unstable and rapid shifts in their environments, making them better able to survive when things suddenly went wrong when the asteroid struck.
Dinosaurs first appeared 230 million years ago when warm conditions from the pole to the equator provided the perfect environment for them to evolve and dominate mammals for more than 100 million years.
Some scientists believe that when the climate cooled and sea levels changed, this was the beginning of the domination of mammals, but the authors of the latest study say that the asteroid impact still plays the most important role because at that time the dinosaurs were getting stronger.
Co-author Jorge García-Girón, from the University of Leon in Spain, added: ‘Our study provides a compelling picture of the ecological structure, food webs, and niches of the last Cretaceous and early Cretaceous dinosaur-dominated ecosystems. Ecosystems dominated by mammals after the asteroid impact.
This helps us understand one of the ancient mysteries of paleontology: why all non-avian dinosaurs died out, while birds and mammals suffered.
The research was published in the journal Science Advances.
How did dinosaurs stretch about 66 million years ago?
Dinosaurs ruled and dominated the Earth about 66 million years ago, before suddenly becoming extinct.
The Cretaceous-Third extinction event is the name given to this mass extinction.
It was believed for many years that a changing climate destroyed the food chain of the mega-reptiles.
In the 1980s, paleontologists discovered a layer of iridium.
This is an element that is rare on Earth but is found in huge amounts in space.
When this date was dated, it specifically coincided with the disappearance of dinosaurs from the fossil record.
A decade later, scientists discovered the massive Chicxulub Crater at the tip of Mexico’s Yucatan Peninsula, which dates back to the period in question.
The scientific consensus now says that these two factors are related, and both may have been caused by a huge asteroid hitting Earth.
With the expected size and velocity of the impact, the collision would have created a massive 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 dinosaurs to survive.
Animals and other plant species had a shorter period of time between generations which allowed them to survive.
There are several other theories as to why these famous animals died out.
One early theory was that small mammals ate dinosaur eggs and another suggests that poisonous angiosperms (flowering plants) killed them.
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