A dinosaur which roamed parts of the world 160 million years ago is thought to have had the longest neck ever seen in an animal, according to scientists.
Known as Mamenchisaurus sinocanadorum, the dinosaur's neck measured 15.1 metres - six times longer than the necks of giraffes and 1.5 times the length of a double-decker bus.
The animal belongs to a subgroup of dinosaurs known as sauropods, which are known for their large size, long neck and tail, four-legged stance and plant-eating diet.
Dippy - the famous dinosaur on display at the Natural History Museum in London - belongs to this group.
Dr Andrew J Moore, a palaeontologist at Stony Brook University, New York, said: "With a 15-metre-long neck, it looks like Mamenchisaurus sinocanadorum might be a record-holder - at least until something longer is discovered."
The M. sinocanadorum roamed east Asia and its fossils were first discovered in China in 1987 within 162-million-year-old rocks.
Dr Moore and his colleagues re-examined the specimens as part of their research into the dinosaurs.
Although M. sinocanadorum is known only from a handful of bones from the neck and skull, scientists were able to reconstruct its size and shape with help from complete skeletons of its closest relatives.
Dr Moore said: "All sauropods were big but jaw-droppingly long necks didn't evolve just once.
"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."
The paleontologists used a technique known as computed-tomography scanning which revealed the vertebrae - back bones - of M. sinocanadorum were lightweight and hollow with air spaces taking up nearly three-quarters of the volume.
Skeleton of 82ft-long dinosaur found in man's backyard in Portugal
First record uncovered of a dinosaur eating a mammal in fossil
According to the researchers, these types of bones are usually seen in small birds.
To compensate for its lightweight bones, M. sinocanadorum had rod-like ribs in the neck about four metres long to help with its stability, the team said.
The biggest dinosaur to have lived was the Patagotitan mayorum, which was thought to be 37.5 metres long and weighed about 57 tonnes.
The research is published in the Journal of Systematic Palaeontology.
(c) Sky News 2023: Dinosaur had longest neck ever seen in an animal, scientists say