150 million-year-old dino eggshells found in Portugal floodplains

Paleontologists have found eggshells fragments belonging to huge meat-eating dinosaurs that stalked a vast floodplain some 150 million years ago in what is now Portugal.

Some of the eggshells, which belonged to two Jurassic-Era theropods, or a group of carnivorous dinosaurs, once harbored embryos of Torvosaurus, the largest predator of its day.

Study co-author Vasco Ribeiro, a paleontologist at the Universidade Nova de Lisboa in Portugal said that it was the equivalent of the T. rex in the Cretaceous, Fox News reported.

Ribeiro and his colleagues arent sure how the eggs came to be abandoned.

Because they are so delicate, dinosaur eggs are a relatively rare find.

Ribeiro and his colleagues found the eggshell fragments at two separate sites, both of which were part of the Lourinh Formation, a geological formation known for its rich Jurassic dinosaur nest sites.

During that time period, the area was a floodplain that cycled through dry seasons and monsoon rains.

The eggshells were shattered and there was no trace of the dinosaur embryos that once coiled inside.

But by analyzing the size, shape and texture of the eggshells, the team was able to deduce which animals left those eggs so long ago.

The shells found at one site came from spherical eggs that were about 6 inches in diameter.

They likely belonged to a Torvosaurus, a massive, bipedal dinosaur that grew up to 36 feet tall.

The eggs at the other site were harder to identify. But the researchers believe the eggs may have contained embryos of Lourinhanosaurus antunesi, a theropod that was about 15 feet long when full-grown.

When intact, the eggs from that site would have been about 5 inches along the long axis and 3.5 inches along the short axis.