Millions of years ago, a shift in atmospheric carbon dioxide allowed herbivores like sauropodomorphs to migrate from South America to Greenland as the planet became milder.
How The Earth Became Milder Helped Sauropodomorphs Migrate
During the late Triassic period, roughly 252 million years in the past, the planet was, for the most part, only a vast arid desert assembled in the supercontinent known as Pangea. Carnivorous dinosaurs roamed the Earth, constantly expanding their range through the land.
Meanwhile, herbivores with diets depending on the abundance of plants were geographically restricted to greener areas which included the larges dinosaurs that ever lived: a group of long-necked dinosaurs called sauropodomorphs.
For millions of years, these long-necked dinos didn't change their habitats and remained in what is now Argentina and Brazil until atmospheric carbon dioxide levels dipped roughly 215 million years ago, according to reports by Chrissy Sexton for Earth.com.
In a study published in the journal Proceedings of the National Academy of Sciences entitled, "Northward dispersal of dinosaurs from Gondwana to Greenland at the mid-Norian (215-212 Ma, Late Triassic) dip in atmospheric pCO2" researchers suggest that the shift in CO2 levels made it easier for groups of herbivores to migrate northward.
In a statement Dennis Kent, a geologist and co-author from Columbia University explains that in principle, dinosaurs would have walked from roughly one pole to the other since there were no oceans or mountains to cross where the migration would have taken the sauropodomorphs roughly 15 million years to migrate.
Migration of Sauropodomorphs
Previously, it was believed that sauropodomorphs migrated around 2015-225 million years ago. However, after measuring magnetism patterns in ancient rocks from Arizona, South America, New Jersey, Greenland, and Europe, the authors found that herbivores migrated closer to 214 million years ago when the planet's climate was rapidly changing.
Research suggests that between 212-215 million years ago the sauropodomorphs arrived in what is now Greenland, CO2 levels were halved at 2,000 parts per million that left researchers to suspect that they even made Earth conditions more hospitable for the large herbivores.
During this time, tropical regions became milder and arid regions became less dry that allowed sauropodomorphs to migrate northward.
Abundant evidence found by researchers of sauropod fossils in Greenland suggests that the climate and environment because suitable for dinosaurs which is why they decided to stick around the area.
Kent explains that once the large herbivores arrived in Greenland, they settled in as indicated by long-fossil records. He adds that fossilized footprints of sauropods can be found in both arid and tropical regions. However, their bodies are not. These suggest that the long-necked herbivores were only passing through as they migrated to Greenland.
Steve Brusatte, a vertebrate paleontologist at the University of Edinburgh not involved with the study explains that research completed by Kent and his team shows how evolution can be understood by analyzing climatic and environmental phenomenons.
Check out more news and information on Paleontology on Science Times.
