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About 162 million years ago, a plant-eating sauropod lumbered near what is now China, with a neck about 10 feet longer than a typical school bus — the longest of any known dinosaur .
The creature’s 49.5-foot-long (15.1-meter) neck allows it to stand in one spot and feed on surrounding vegetation — maximizing food consumption while conserving energy.
The fossilized remains of the dinosaur, Mamenchisaurus sinocanadorum, were discovered in the Xinjiang region of northwestern China in 1987 and were first described in a 1993 scientific paper. The dinosaur was named after the joint Canadian-Chinese team that unearthed the fossil.
In a new analysis of the fossil, published Wednesday in the Journal of Systematic Palaeontology, paleontologists used computerized scans of the terrain not yet widely available 30 years ago to compare M. sinocanadorum with other related sauropods unearthed Last few years.
“Mamenchisauridae are important because they broke the neck length limit and were the first sauropod lineage to do so. With a 15-meter-long neck, it looks like South China Mamenchisaurus might be the record-holding – at least until longer necks were discovered,” study says lead Andrew Moore, a paleontologist and assistant professor at Stony Brook University in New York, said in a statement.
Paleontologists were able to infer the length of the neck by studying the specimen’s three well-preserved vertebrae and comparing them to the neck bones of closely related dinosaurs.
“We actually happen to know who it’s related to, which provides a good comparison. In this case, it’s evolutionarily well nested in a lineage that we know has 18 cervical (neck) vertebrae, ’ Moore explained. “We can zoom in on the comparator to calculate the absolute neck length.”
longest full neck Moore said the dinosaur fossils recorded by scientists belonged to a species called Xinjiang Titan, which was about 5 feet (1.5 meters) shorter than the neck of M. sinocanadorum.
The study also revealed Interesting details about these gigantic dinosaurs. Similar to the light skeleton of birds, M. sinocanadorum’s skeleton is filled with air, rather than marrow, which is characteristic of most mammalian skeletons. CT scans show that air occupies 69% to 77% of the vertebral volume.
“Presumably, this is an important mechanism for building such a long neck, because it would be so heavy,” Moore said.
Although the posture of some sauropods Biomechanical studies suggest that the necks of mamenchisaurids likely stood upright in a swan-like fashion, with the necks elevated above horizontal at an angle of about 20 to 30 degrees, Moore said.
However, even at this relatively shallow angle, the neck The extreme length still means that the animal’s head can reach a height of about 24.6 to 32.8 feet (7.5 meters to 10 meters) above the ground.
According to the study, sauropod evolutionary adaptations — large body size and vegetarianism — have no modern counterparts. But the lineage of these long-necked dinosaurs was so successful that different sauropod species arose early in the age of dinosaurs and went extinct 66 million years ago.
“They seem to have been engineered to be efficient food gatherers, and that’s what the neck allows them to do… plant themselves in a space, eat the surrounding plants, and then only move when necessary.
“As for why Mamenchisaurus had a longer neck among the sauropods? Maybe it was just more efficient. … Hard to say, but it’s clearly at the heart of their biology.”