Dinosaur nest discovered inside ‘Dragon’s Tomb’: Remains of tiny ‘duck-billed babies’ found near fossilised shell fragments
The remains of a litter of ‘duckbilled’ dinosaurs have been discovered in an area known as the Dragon’s Tomb in Mongolia.
Scientists say the specimens were found close to fragments of eggshell and that the ‘babies’ were probably in the earliest stages of development.
They believe the creatures belonged to a group of Saurolophus angustirostris – a type of giant hadrosaur – and that they are all likely to be from the same nest.
The remains of a litter of ‘duckbilled’ dinosaurs have been discovered in an area known as the Dragon’s Tomb in Mongolia. Scientists say the specimens (one pictured) were found close to fragments of eggshell and that the ‘babies’ were probably in the earliest stages of development
Scientists described three or four perinatal specimens – or ‘babies’ – and two associated eggshell fragments.
Scientists are not sure whether the individuals were still in the eggs or had just hatched when they died, but they were dead and partly decomposed when they were buried by river sediment during the wet summer season.
Dragon’s Tomb, in the Nemegt basin in the northwestern Gobi Desert, is a well-known location for finding Late Cretaceous dinosaur fossils.
Scientists say the young dinosaurs were likely part of a nest originally located on a river sandbank. They believe that the specimens were probably Saurolophus angustirostris (illustrated) – a type of giant hadrosaur – and that they are all likely to be from the same nest
Dragon’s Tomb, in the Nemegt basin (marked) in the northwestern Gobi Desert, is a well-known location for finding Late Cretaceous dinosaur fossils
Leonard Dewaele, of Ghent University and the Royal Belgian Institute of Natural Sciences, said the skull length of the Saurolophus found was around five per cent that of the largest known S. angustirostris specimens, indicating that they were in the earliest development stages.
But the bones already resembled S. angustirostris characteristics, including the upwardly directed snout also known as premaxillary bones.
The study said the specimens did not yet have the characteristic cranial crest at the top of the head and areas of the skull – the cervical neural arches – were not yet fused, which suggest they may have been in the earliest stages of the development
Dewaele said the specimens did not yet have the characteristic cranial crest at the top of the head and areas of the skull – the cervical neural arches – were not yet fused, which suggest they may be in the earliest stages of the development.
He added: ‘The poorly developed crest in Saurolophus babies provides evidence of ontogenetic crest growth within the Saurolophini tribe.
‘The Saurolophini are the only Saurolophinae to bear supra cranial crests as adults.’
Scientists are not sure whether the individuals were still in the eggs or had just hatched when they died, but they were dead and partly decomposed when they were buried by river sediment during the wet summer season. The arrows point to the location of each specimen
This image is a close-up of a cervical vertebra, showing the suture dividing the neural arch. The fibrous and spongy bone texture suggests that they had not fused and were still in development
He said the fossilised eggshell fragments associated with the specimens closely resemble those found from S. angustirostris relatives in Mongolia, and suggested they may bridge a gap in our knowledge of the development of S. angustirostris.