A team of paleontologists from the United States, Canada and Argentina has analyzed the fossilized eggs of two different non-avian dinosaurs, Protoceratops and Mussaurus, and found that the eggs resembled those of turtles in their microstructure, composition, and mechanical properties. They’ve also found that hard-shelled eggs evolved at least three times independently in the dinosaur family tree. The exceptionally preserved Protoceratops specimen...