Among the youngest of its kind, a new dinosaur dubbed Dzharatitanis kingi was unearthed by U.S. and Russian researchers in Asia, and the fossil's location provides insight into how Earth’s continents were bridged and populated several million years ago.
Published Wednesday in PLOS ONE, the report documenting the finding says the long-necked, stringy-tailed, four-legged dinosaur was the first of its kind to be uncovered in Earth's largest continent. And because dinosaurs from its family had previously been detected within a limited region of South America, Africa and Europe, the findings support the idea that all four continents had a connecting route. They also speak to past biodiversity.
The features of D. kingi are not too far off from its siblings in the diplodocoid clade Rebbachisauridae, including characteristics such as low-angled teeth. But Hans-Dieter Sues, an author of the paper and a researcher from the Smithsonian National Museum of Natural History in Washington, D.C., was intrigued to see that, "The structure of the backbone in these dinosaurs is very unusual.” As an example, the study describes its spine as hollow with air-filled cavities.
The latest dinosaur, similar in aesthetic to the late-Jurassic Diplodocus from the American West, lived about 90 million years ago throughout the late-Cretaceous period.
Sues noted that this period was extremely warm, remarking that, "These animals lived during a time with a super greenhouse climate.”
The period also saw the continents on Earth arranged very differently than they are today — much closer together, and in some parts, fully connected. The distribution is a departure from the well-known Pangaea. The latter was a supercontinent, meaning that all of the landmasses were fused into one major landform; it started to break apart about 180 million years ago.
“With the other fossils found by our expeditions, [our discovery] established the presence of a very diverse ecosystem at the western end of the landmass, that encompassed much of Asia and western North America,” explained Sues.
He relayed to The Academic Times that in 1997, a crucial fossil from the Kyzylkum Desert of Uzbekistan was found. It served as the foundation for the team’s 10-year research endeavor in the area, which unveiled a variety of different species' remains and ultimately led to finding the new sauropod.
“It was the goal of this, and latter expeditions, to search for fossils of late-Cretaceous amphibians, reptiles and mammals from a region that was still poorly known in terms of its fossils,” he said. “We did not expect to find a record of this group of dinosaurs, as they were previously not known from Asia.”
According to the study, the dinosaurs “possibly dispersed from Europe to Asia via a land bridge across the Turgai Strait.” This strait was a shallow body of salt water between the two continents, at the time. Today, this range stretches from the the Mediterranean Sea to the Arctic Ocean.
Going forward, Sues and his team will continue to sift through the abundance of fossils gathered over the years by his team, building upon knowledge of the Cretaceous era as its history unfolds.
“We collected many fossils over a period of 10 years," he said. "They included several new species of dinosaurs, but also an unexpected diversity of early mammals and many other vertebrates."
The paper, “First rebbachisaurid sauropod dinosaur from Asia,” was published Feb. 24 in PLOS ONE. It was authored by Alexander Averianov, Russian Academy of Sciences and Hans-Dieter Sues, National Museum of Natural History, Smithsonian Institution.