Scientists recently uncovered the largest group of fossilized pterosaur eggs ever. In a 10-foot-long sandstone block in northwest China, they came across 215 eggs – 16 of which have embryonic remains. Discoveries of pterosaur eggs are exceedingly rare. The only previous discoveries with an intact embryo and well-preserved 3D structure include three in Argentina and five in China, so researchers around the world are especially thrilled with this latest find. Pterosaurs may have been around on Earth up to 225 million years ago, but vanished with the dinosaurs around 65 million years ago.