
Birds and bird eggs are familiar stuff: we see them daily in our backyards and even in our kitchens. But ask the classic questions: where did egg laying come from and how did it get that way? Answers are hard to come by.
A gravid theropod dinosaur discovered with fossilized eggs still inside it helps explain how birds evolved their distinctive ways of reproducing. Described in a paper in the Journal of Vertebrate Paleontology by recent UCMP alumnus Ashley Poust and co-authors from China and Montana, this rare fossil provides a unique glimpse into the lives and deaths of dinosaurs. The discovery of a reproductively active female dinosaur allowed the scientists to test how a mother dinosaur’s bones grew, how old she was, what type of eggs she laid and how many at a time, and much more.

This work was funded in part by a Doris O. and Samuel P. Welles Grant from the UCMP. For more about dinosaur eggs and parenting with quotes from Ashley, check out the new article in Smithsonian magazine.
Citation: Jin, X., D. J. Varricchio, A. W. Poust, and T. He. 2020. An oviraptorosaur adult-egg association from the Cretaceous of Jiangxi Province, China. Journal of Vertebrate Paleontology. DOI: 10.1080/02724634.2019.1739060.