The bowl-shaped nest measuring 2.3 feet in diameter and containing the remains of Protoceratops andrewsi dinosaurs was found in Tugrikinshire, Mongolia.
"Finding juveniles at a nest is a relatively uncommon occurrence, and I cannot think of another dinosaur specimen that preserves 15 juveniles at its nest in this way," said David Fastovsky, a University of Rhode Island professor of geosciences.
An analysis of the 70-million-year-old fossils found all 15 were about the same size and had achieved the same state of growth and development, suggesting they represent a single clutch from a single mother, a university release said Monday.
They were likely less than a year old when they died, Fastovsky said.
"Death likely occurred during a desert sandstorm," he said. "My guess is that the initial and present-day dryness contributed significantly to the superb preservation, not just of Protoceratops, but of all the fossils from this unit."
Video of Victoria’s Secret models trying to 'twerk' hits Instagram
Megyn Kelly: Santa Claus and Jesus are both white men