The discovery of more than 250 fossilized eggs reveals intimate details about the lives of titanosaurs in the Indian subcontinent, according to a study published in the journal PLOS ONE by Harsha Dhiman of the University of Delhi, New Delhi and colleagues.
The Lameta Formation in central India is well-known for its fossils of dinosaur skeletons and eggs of the Late Cretaceous Period. Recent work in the area uncovered 92 nesting sites containing a total of 256 fossil eggs belonging to titanosaurs, which were among the largest dinosaurs ever to live. Dhiman and colleagues were able to make inferences about these dinosaurs’ life habits after thoroughly examining these nests.
The authors identified six different egg-species (oospecies), suggesting a greater diversity of titanosaurs than is represented by skeletal remains from this region. The team inferred from the layout of the nests that these dinosaurs buried their eggs in shallow pits like modern-day crocodiles.
Certain pathologies found in the eggs, such as a rare case of a “egg-in-egg,” suggest that titanosaur sauropods had a reproductive physiology similar to that of birds and possibly laid their eggs sequentially, as seen in modern birds. The presence of multiple nests in the same area suggests that these dinosaurs exhibited colonial nesting behavior like many modern birds. However, the close spacing of the nests left little room for adult dinosaurs, supporting the idea that adults left the hatchlings (newborns) to fend for themselves.
Details of dinosaur reproductive habits can be difficult to determine. These fossil nests contain a wealth of information about some of the largest dinosaurs in history, and they come from just before the dinosaur extinction. The findings of this study add significantly to paleontologists’ understanding of how dinosaurs lived and evolved.
“Our research has revealed the presence of an extensive hatchery of titanosaur sauropod dinosaurs in the study area and offers new insights into the conditions of nest preservation and reproductive strategies of titanosaur sauropod dinosaurs just before they went extinct,” says lead author Harsha Dhiman.
“Together with dinosaur nests from Jabalpur in the upper Narmada valley in the east and those from Balasinor in the west, the new nesting sites from Dhar District in Madhya Pradesh (Central India), covering an east-west stretch of about 1000 km, constitute one of the world’s largest dinosaur hatcheries,” says Guntupalli V.R. Prasad, co-author and leader of the research team.