New Sauropod Dinosaur Unveiled: Lingwulong shenqi
Lingwulong shenqi, which lived approximately 174 million years ago (Middle Jurassic period), is the earliest known example of a type of sauropod dinosaur called a neosauropod.
Sauropod dinosaurs originated around 200 million years ago, but they only started to dominate terrestrial ecosystems by developing gigantic body size and new adaptations for obtaining and processing plant food.
These giant neosauropod descendants were thought to originate around 160 million years ago, rapidly diversifying and spreading across the world during a time window perhaps as short as just 5 million years.
“We were surprised to find a close relative of Diplodocus in East Asia 174 million years ago,” said Professor Paul Upchurch, from the Department of Earth Sciences at University College London, UK.
“It’s commonly thought that sauropods did not disperse there until 200 million years ago and many of their giant descendants, reached this region much later, if at all.”
“Our discovery of Lingwulong shenqi demonstrates that several different types of advanced sauropod must have existed at least 15 million years earlier and spread across the world while the supercontinent Pangaea was still a coherent landmass. This forces a complete re-evaluation of the origins and evolution of these animals.”
For the study, Professor Upchurch and colleagues analyzed the fossilized skeletons of 7-10 individual dinosaurs that were found together in rocks in 2005.
“We organized four excavations at a new dinosaur site in the lower Middle Jurassic Yanan Formation at Ciyaopu, Lingwu, Ningxia Hui Autonomous Region, which resulted in the discovery of fossil material comprising 7-10 partial skeletons (including portions of two skulls), ranging from juveniles to adults,” they said.
The new evidence also reinforces the growing realization that the Early Jurassic (200-175 million years ago), was a key time in dinosaur evolution, witnessing the origins and diversification of many groups that went on to dominate the later Jurassic and Cretaceous.
“Diplodocus-like neosauropods were thought to have never made it to East Asia because this region was cut-off from the rest of the world by Jurassic seaways, so that China evolved its own distinctive and separate dinosaur fauna,” said Dr. Xing Xu, from the Institute of Vertebrate Paleontology & Paleoanthropology, Chinese Academy of Sciences.
“However, Lingwulong shenqi shows that these Diplodocus-like sauropods were present after all, and implies that the isolation of East Asia was less profound and short-lived than we realized.”
The research is published in the journal Nature Communications.
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Xing Xu et al. 2018. A new Middle Jurassic diplodocoid suggests an earlier dispersal and diversification of sauropod dinosaurs. Nature Communications 9, article number: 2700; doi: 10.1038/s41467-018-05128-1
Source: www.sci-news.com