The long-known fact about crocodiles being egg laying animals since prehistoric times has been debunked. Scientists have found out that a 250-million-year-old 'terrible-headed lizard' fossil has an embryo inside.

This notable discovery is making scientists doubt other animals' pre-historic ancestors too. The newly found fossil is from a far-away ancestor of the crocodile. It has lived in shallow seas of South China in the Middle Triassic. It is 250-million years old and looks like a 'terrible-headed lizard'.  It has an embryo inside its ribcage which only mammal and other live birth animals are found to have, stated Science Daily.

The new discovery only suggests that it is the very first evidence for an egg-laying only reptile to be a live birth. According to DMail Online, researchers from Hefei University of Technology in China discovered the new fossil with long-necked called Dinocephalosaurus. At first, the researchers who found the fossil weren't exactly sure it was indeed the baby. However, after further investigation, it is indeed the mother's baby.

"Further evolutionary analysis reveals the first case of a live birth in such a wide group containing birds, crocodilians, dinosaurs and pterosaurs among others, and pushes back evidence of reproductive biology in the group by 50 million years," Professor Jun Liu, who led the study, said. Before the Jurassic period, all scientists thought that reptiles and all other egg-laying animals have been laying eggs all along. But after this discovery, they were proven wrong.

The combination of live birth and genotypic sex determination is necessary for animals like Dinocephalosaurus to become aquatic, stated Professor Mike Benton, another co-author from the School of Earth Sciences at the University of Bristol. The new discovery and its analysis of evolution clearly state that there are no grounds that archosauromorphs could not have evolved live birth, he added.

This new discovery has definitely rewritten the long understanding of the evolution of the reproductive system. Scientists are hoping to discover more facts about pre-historic animals.