Around 201 million years ago, volcanic eruptions caused freezing winters in the Arctic that all non-insulated reptiles were wiped out during the End Triassic Extinction, paving the way for large dinosaurs to dominate.
After that event, Earth was changed, and about 40% of all four-legged animals were wiped out, with the exact cause remaining unknown until today. But researchers found out how early dinosaurs were successful in surviving while others were not.
Freezing Arctic Paved Way for Large Dinosaurs' Era of Dominance, Study Reveals
Evidence of Freezing Temperatures in End Triassic Extinction Found in China
Paul Olsen, an associate professor of Earth and environmental sciences at Rensselaer Polytechnic Institute and the study's lead researcher, said that there was no previous evidence of freezing temperatures during the End Triassic Period not until they found it in ancient lakes in northern China.
Mirage News reported that these ancient lakes formed at high latitudes during the Late Triassic Period. Researchers found a unique assemblage of minerals and grains in lake sediments that indicate they have been in deep icy waters in the past.
More so, the Earth was in a greenhouse state at that time because of the doubling amount of carbon dioxide in the atmosphere that warmed the climate. That also led the Arctic's temperature to drop below freezing temperature because the eruptions released so many sulfate aerosols in the upper atmosphere that reflected solar radiation and acted as a driver for the freezing winters for many decades.
Researchers explained that animals in the tropics that adapted to the warm temperatures did not survive the sudden winters and acid rain produced by the sulfate in rain droplets. Due to the extreme temperatures at that time, only creatures that could handle them survived, such as early dinosaurs.
They had feathers as insulation, but others did not have them, which led to their extinction. The team added that this insightful analysis shows that dinosaurs that evolved resilient features helped them adapt to changing environments to survive climatic upheavals. The data gave scientists an idea of what could also happen to the future of Earth as climate change and global warming worsen.
How Did Dinosaurs Cope With Snow
The Tyrannosaurus rex may have walked through the cold Arctic region millions of years ago, indicating that they managed to thrive in snowy weather along with other dinosaurs. Paleontologists found fossil evidence that showed dinosaurs nested in polar regions year-round that perhaps slowed their growth due to the harsh seasons.
But they adapted well, showing how wonderfully flexible dinosaurs were. These dinosaurs were particularly feather predators and small herbivores that walked on two legs. According to Smithsonian Magazine, some dinosaurs likely dug in to survive the harshest months of winter, given that scientists found some burrow-like structures that contain small, herbivorous dinosaurs.
Steve Poropat, a paleontologist from Monash University, said that the clearest evidence of polar dinosaur adaptation is the composition of fauna. Identifying which dinosaur species thrived in polar regions offers some insights into how they were able to cope with the long cold winter nights.
They found theropods, ornithopods, and ankylosaurs at heaps of sites that used to experience extremely cold temperatures. However, they did not find long-necked, plant-eating dinosaurs called sauropods, which suggests that they could not adapt to colder environments.
The fact that early dinosaurs used to thrive in polar regions is relatively new to scientists, and it is even more fascinating to know that dinosaurs became specialists in the ancient north to become capable of surviving an array of environmental conditions. Discoveries like these continue to highlight how successful dinosaurs were until they became extinct.
RELATED ARTICLE: T.Rex May Have Short Arms Due to Sexual Selection Based on 95 Million-Yea-Old Fossil Discovered in Patagonia, Argentina
Check out more news and information on Paleontology in Science Times.
