The discovery of more than 250 fossilized eggs reveals intimate details about titanosaur life in the Indian subcontinent, according to a study published January 18, 2022 in the open access journal PLOS ONE by Harsha Dhiman of the University of Delhi, New Delhi and colleagues .

Located in the Narmada Valley of central India, the Lameta Formation is known for the fossils of dinosaur skeletons and eggs from the Late Cretaceous Period. Recent work in the area has uncovered 92 breeding grounds containing a total of 256 fossil eggs of titanosaurs, which were among the largest dinosaurs that ever lived. Detailed examination of these nests has enabled Dhiman and colleagues to draw conclusions about the life habits of these dinosaurs.

The authors identified six different egg species (oospecies), suggesting a greater diversity of titanosaurs than is represented by skeletal remains from this region. Based on the layout of the nests, the team concluded that these dinosaurs buried their eggs in shallow pits, like modern crocodiles. Certain pathologies found in the eggs, such as a rare “egg-in-egg” case, indicate that titanosaur sauropods had a reproductive physiology parallel to that of birds and may have laid their eggs in a sequential fashion like can be seen in modern birds. The presence of many nests in the same area suggests that these dinosaurs exhibited colonial nesting behavior like many modern birds. But the small spacing between the nests left little room for adult dinosaurs, supporting the idea that adults abandoned the young (newborns) to their own devices.

Field photos of eggs and egg contours with different characteristics. (A) Completely unhatched egg from clutch P43. (B) Almost completely intact circular outline of the egg, possibly indicating that it did not hatch and no loose eggshells were found in the clutch P6. (C) Compressed egg from clutch DR10 showing the hatching window (arrow shows opening) and some eggshells collected just around the hatching window (circled) possibly representing the remnants of the hatching window. (D) Egg of clutch P26 with curved outline. (E) Deformed egg of clutch P30 with egg surfaces sliding past each other.
Field photos of eggs and egg contours with different characteristics. (A) Completely unhatched egg from clutch P43. (B) Almost completely intact circular outline of the egg, possibly indicating that it has not yet hatched and no loose eggshells were found in the clutch P6. (C) Compressed egg from clutch DR10 showing the hatching window (arrow shows opening) and some eggshells collected just around the hatching window (circled) possibly representing the remnants of the hatching window. (D) Egg of clutch P26 with curved outline. (E) Deformed egg of clutch P30 with egg surfaces sliding past each other. Dhiman et al., 2023, PLOS ONE, CC-BY 4.0

Details of dinosaurs’ reproductive habits can be difficult to determine. These fossil nests provide a wealth of data on some of the largest dinosaurs in history, and they come from a time shortly before the age of dinosaurs came to an end. The insights gained from this study contribute significantly to paleontologists’ understanding of how dinosaurs lived and evolved.

Harsha Dhiman, lead author of the study, adds: “Our research has revealed the presence of an extensive hatchery of titanosaur sauropod dinosaurs in the study area and provides new insights into the nest preservation conditions and reproductive strategies of titanosaur sauropod dinosaurs just before they became extinct.”

Guntupalli VR Prasad, co-author and leader of the research team, adds: “Together with dinosaur nests from Jabalpur in the upper Narmada valley to the east and those from Balasinor to the west, the new breeding grounds of Dhar district in Madhya Pradesh (Central India), which span an east-west range of about 1000 km occupy one of the largest dinosaur breeding grounds in the world.”

Magazine reference

  1. Dhiman H, Verma V, Singh LR, Miglani V, Jha DK, Sanyal P, et al. (2023) New Late Cretaceous titanosaur sauropod dinosaur egg claws from lower Narmada Valley, India: paleobiology and taphonomy. PLOS ONE 18(1): e0278242. DOI: 10.1371/journal.pone.0278242