New analysis of the oldest North American fossils has revealed that dinosaurs roamed the northern hemisphere millions of years earlier than previously thought. The discovery, made by a team of researchers from the University of Wisconsin-Madison, pushes back our understanding of the emergence and spread of dinosaurs across the planet.
The finding is significant, as it challenges the long-held narrative that dinosaurs emerged on the southern portion of the ancient supercontinent Pangea called Gondwana before spreading to the northern half named Laurasia. The new dinosaur species, Ahvaytum bahndooiveche, has been dated to around 230 million years ago and is now considered the oldest known Laurasian dinosaur.
The team, led by Dave Lovelace and Aaron Kufner, discovered the fossils in a layer of rock known as the Popo Agie Formation in present-day Wyoming. The analysis of the fossils revealed that Ahvaytum bahndooiveche was likely an early sauropod relative, a group of herbivorous dinosaurs characterized by their long necks and tails.
The discovery has shed new light on the distribution of dinosaurs across North America during the Carnian pluvial episode, a period of intense climatic change that transformed large deserts into more hospitable habitats for early dinosaurs. The team’s findings also suggest that dinosaurs or their cousins were present in the region a few million years prior to Ahvaytum.
What is most notable about this discovery is not just its age but also the way it was made possible through collaboration and reciprocity with the Eastern Shoshone Tribe, whose ancestral lands include the site where the fossils were found. The tribe’s elders and middle school students played a crucial role in the naming process, which has been hailed as an important step towards greater inclusion and respect for Indigenous knowledge in scientific research.
The discovery of Ahvaytum bahndooiveche not only expands our understanding of North America’s dinosaur history but also highlights the importance of collaboration and coexistence between scientists and Indigenous communities.
Source: https://news.wisc.edu/dinosaurs-roamed-the-northern-hemisphere-millions-of-years-earlier-than-previously-thought-according-to-new-analysis-of-the-oldest-north-american-fossils