Photo: Dinghua Yang/AFP/Getty Images
This pregnant Dinocephalosaurus, a long-necked marine reptile, didn’t lay eggs but instead gave birth to live young 245m years ago.
After uncovering new evidence, surprised scientists are revising a long-held understanding of the pre-dinosaur Dinocephalosaurus.
According to a Reuters story at the Guardian, “An extraordinary fossil unearthed in southwestern China shows a pregnant long-necked marine reptile that lived millions of years before the dinosaurs with its developing embryo, indicating the creature gave birth to live babies rather than laying eggs.
“Scientists said [in February that] the fossil of the unusual fish-eating reptile called Dinocephalosaurus, which lived about 245m years ago during the Triassic Period, changes the understanding of the evolution of vertebrate reproductive systems.
“Mammals and some reptiles including certain snakes and lizards are viviparous, meaning they give birth to live young.
“Dinocephalosaurus is the first member of a broad vertebrate group called archosauromorphs that includes birds, crocodilians, dinosaurs and extinct flying reptiles known as pterosaurs known to give birth this way, paleontologist Jun Liu of China’s Hefei University of Technology said. …
“ ‘I think you’d be amazed to see it, with its tiny head and long snaky neck,’ said University of Bristol paleontologist Mike Benton, who also participated in the research published in the journal Nature Communications.
“Its body plan was similar to plesiosaurs, long-necked marine reptiles akin to Scotland’s mythical Loch Ness Monster that thrived later during the dinosaur age, though they were not closely related.
“Not laying eggs provided advantages to Dinocephalosaurus, the researchers said. It indicated the creature was fully marine, not having to leave the ocean to lay eggs on land like sea turtles, exposing the eggs or hatchlings to land predators.” More here.
I admire scientists for continuously revisiting accepted wisdom when they find new data. The only complaint I have about the story concerns the Loch Ness Monster, an old friend of mine. Should one really call it mythical? Perhaps the data just haven’t floated to the surface yet.
Suzanne's Mom's Blog 
I think it’s fascinating that prehistory is constantly re-written–no end to the things we don’t fully understand!
I’m a dinosaur fan ,so the Loch Ness monster was a delight to see. I believe these wonderful large creatures lived as there are fossils to prove that…just not millions of years ago ,I don’t believe in evolution.😊
When Suzanne was a baby, she loved to hear her big brother say the names of dinosaurs. We sort of chanted them. It always made her laugh. Who knows why.