It’s no secret that sauropods – a clade of giant dinosaurs that includes the famous Brachiosaurus – had really long necks, but now paleontologists claim to have identified the species that takes the crown. According to the team, Mamenchisaurus has the longest neck of any known animal ever, measuring almost 50 ft (over 15 m).
Mamenchisaurus sinocanadorum was first discovered in China in 1987, and dates back about 162 million years to the Late Jurassic period. The species had the familiar body plan of most sauropods – a gigantic, stocky barrel of a body held up by four huge elephant-like legs, with a long neck at one end counterbalanced by a similarly long tail. The relatively small head sought out an endless supply of plants to graze on. It was, in the words of Jurassic Park’s Dr. Alan Grant, “kind of a big cow.”
But figuring out exactly which sauropod had the longest neck is trickier than you might expect. That’s because complete skeletons of these dinosaurs are hard to come by – after all, you’d need a grave the size of an apartment building to completely bury one of these giants quickly enough to favor fossilization.
For the new study, researchers at Stony Brook University, the London Natural History Museum, Yunnan University and the Zigong Dinosaur Museum examined the evolutionary history of the Mamenchisauridae family. This involved comparing their bones to those from closely related species, which have far more complete skeletons, and using that data to infer the dimensions of these animals.
In doing so, the team concluded that Mamenchisaurus sinocanadorum had a neck that stretched about 15.1 m (49.5 ft) long. That’s six times longer than that of the giraffe, which has the longest neck of any living animal, and pips the previous record-holder, a dinosaur called Sauroposeidon, which is thought to have had a neck up to 12 m (39 ft) long.
“Mamenchisaurids are important because they pushed the limits on how long a neck can be and were the first lineage of sauropods to do so,” said Dr. Andrew Moore, lead author of the study. “With a 15-meter-long neck, it looks like Mamenchisaurus sinocanadorum might be a record-holder – at least until something longer is discovered.”
The team also uncovered evidence for how the dinosaur could support itself without collapsing under its own weight. CT scans of the vertebrae revealed the bones were mostly hollow, with air comprising up to 77% of their volume. This would have made them relatively light, using the same weight-saving mechanism as the skeletons of modern birds. To prevent injuries, the neck bones were strengthened by 4-m (13-ft) -long rods protruding from the vertebrae that formed bundles along either side of the neck.
The research was published in the Journal of Systematic Palaeontology.
Source: London Natural History Museum
