How Long Did It Take to Hatch a Dinosaur Egg? 3-6 Months

June 29,2017

A human typically gives birth after nine months. An ostrich hatchling emerges from its egg after 42 days. But how long did it take for a baby dinosaur to incubate?

Groundbreaking research led by a Florida State University professor establishes a timeline of anywhere from three to six months depending on the dinosaur.

Proceedings of the National Academy of Sciences"Some of the greatest riddles about dinosaurs pertain to their embryology -- virtually nothing is known," Erickson said. "Did their eggs incubate slowly like their reptilian cousins -- crocodilians and lizards? Or rapidly like living dinosaurs -- the birds?"

Because the eggs of dinosaurs were so large -- some were about 4 kilograms or the size of a volleyball -- scientists believed they must have experienced rapid incubation with birds inheriting that characteristic from their dinosaur ancestors.

To do that, they accessed some rare fossils -- those of dinosaur embryos.

The two types of dinosaur embryos researchers examined were those from -- a sheep-sized dinosaur found in the Mongolian Gobi Desert whose eggs were quite small (194 grams) -- and , an enormous duck-billed dinosaur found in Alberta, Canada with eggs weighing more than 4 kilograms.

Researchers found what they were looking for on those microscope slides. Growth lines on the teeth showed researchers precisely how long the dinosaurs had been growing in the eggs.

<span style="font-size:18px;font-family:"">"These are the lines that are laid down when any animal's teeth develops," Erickson said. "They're kind of like tree rings, but they're put down daily. We could literally count them to see how long each dinosaur had been developing."

Protoceratops Hypacrosaurus"Dinosaur embryos are some of the best fossils in the world," said Mark Norell, Macaulay Curator for the American Museum of Natural History and a co-author on the study. "Here, we used spectacular fossils specimens collected by American Museum expeditions to the Gobi Desert, coupled them with new technology and new ideas, leading us to discover something truly novel about dinosaurs."

In addition to finding that dinosaur incubation was similar to primitive reptiles, the researchers could infer many aspects of dinosaurian biology from the results.

The biggest ramification from the study, however, relates to the extinction of dinosaurs. Given that these warm-blooded creatures required considerable resources to reach adult size, took more than a year to mature and had slow incubation times, they would have been at a distinct disadvantage compared to other animals that survived the extinction event.

This research was supported by the National Science Foundation.

Mr. Zhou1


Mr. Zhou


Mr. Zhou222


Mr. Zhou