Eggs containing embryos belonged to two different species, researchers said
By: Web Writing
Argentina.- Scientists have unearthed in Argentina and in Mongolia, the first fossils of soft-shell dinosaur eggs, a discovery that suggests that the earliest species of these animals produced eggs with this characteristic before those of hard-shell eggs predominated.
The eggs containing embryos, rather with a leather-like surface on the outside rather than the hard, calcified surface like that of bird eggs, belonged to two different species, researchers said on Wednesday.
One of them is a dinosaur from Patagonia called Mussaurus that lived about 200 million years ago, while the other is the Gobi Desert Protoceratops, almost 75 million years old, they added.
A discovery that breaks paradigms
For a long time it was believed that all dinosaurs they laid hard-shell eggs, like modern birds, descendants of dinosaurs with feathers, and the crocodile family. Many turtles, lizards, and snakes lay soft-shelled eggs.
However, relatively few dinosaur egg fossils have been found, and those discovered belong to only a handful of groups, including carnivores.
Digging up soft-shell eggs of species so dissimilar that they lived in such distant spaces and times indicate that many lineages, including the earliest dinosaurs that appeared 230 million years ago, could have laid such eggs, specialists said.
« Soft shell eggs are not easily preserved as fossils »
Mussaurus was six meters long and was one of the first members of the dinosaurs long necked that ate plants from the sauropod lineage. Its 13-centimeter egg had a rather spherical shape.
Protoceratops was a sheep-sized herbivore that was a member of the Ceratopsian lineage of dinosaurs with beaks, many of which had horns, although this was not the case. Their 10-centimeter eggs were rather oblong.
(With information from .)