Researchers have uncovered 92 nesting sites containing a total of 256 fossil eggs in central India's Narmada Valley belonging to titanosaurs, which were among the largest dinosaurs to have ever lived.
The finding, published in the journal PLOS ONE, reveals intimate details about the lives of titanosaurs in the Indian subcontinent.
The Lameta Formation, located in the Narmada Valley of central India, is well-known for fossils of dinosaur skeletons and eggs of the Late Cretaceous Period that lasted from about 145 to 66 million years ago, the researchers said.
Detailed examination of these nests allowed researchers at the University of Delhi, New Delhi and colleagues to make inferences about the life habits of these dinosaurs.
They identified six different egg-species, suggesting a higher diversity of titanosaurs than is represented by skeletal remains from this region.
Based on the layout of the nests, the team inferred 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 "egg-in-egg," indicate that titanosaur sauropods had a reproductive physiology that parallels that of birds and possibly laid their eggs in a sequential manner as seen in modern birds.
The presence of many nests in the same area suggests these dinosaurs exhibited colonial nesting behaviour 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.
These fossil nests provide a wealth of data about some of the largest dinosaurs in history, and they come from a time shortly before the age of dinosaurs came to an end, the researchers said.
The findings contribute significantly to paleontologists' understanding of how dinosaurs lived and evolved, they added.