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Scientists have discovered a dramatic death scene. It took place 67 million years ago. It involves a very large snake, a newly hatched dinosaur, and some crafty detective work. NPR's Christopher Joyce reports that the discovery is among the rarest - fossils that reveal not just ancient animal remains but animal behavior.
CHRISTOPHER JOYCE: When Jeffrey Wilson was a student, he was fascinated by stories of fields of dinosaur eggs found in India. Later, as a professor at the University of Michigan, he visited the scientists in India who showed him a broken fossilized egg encased in a briefcase-sized block of stone. He leaned in to take a closer look and saw something else.
Professor JEFFREY WILSON (University of Michigan): And I was stunned when I saw it, because, you know, sort of leaping out at me were the peculiar articulations between the vertebrae on a snake, and so I had no idea that there would be a snake there but there it was sitting in front of me.
JOYCE: With permission from the Indian government, Wilson put the stone in his backpack and flew home. He emphasizes that he did not check the bag. Wilson spent a year cleaning the stone. And bit by bit it revealed more of the egg and more of the snake. But it's what the snake was doing that turned this rare find into something even more unusual a grim tableau right out of a science fiction movie.
Prof. WILSON: It was amazing, because we realized that not only do we have an egg, not only do we have a chain of vertebrae, but they are arranged in a coil, and on top of the coil was a skull.
JOYCE: The snake was coiled around the broken eggshell. But wait, there's more.
Prof. WILSON: Next to that coil, eggshell, skull, was a solid egg, and another solid egg, and then some larger bones.
JOYCE: Those bones belonged to a baby sauropod. Full-grown sauropods were the vegetarian 100-ton giants of the dinosaur world. But the baby was only about a foot-and-a-half long. It had apparently just hatched from that broken egg. The snake, about 11 feet long, had been waiting for the baby to hatch in order to eat it.
Wilson says scientists have since found three snake fossils and more eggs at the same site this one came from. And they add new details to a 67-million-year-old story.
Prof. WILSON: So the sauropods, these big dinosaurs, would come in, they would use their hind limb and probably kick out a small depression. They would squat down, they would lay a clutch of six to 12 eggs, they would cover it up with a little layer of sediment and maybe some vegetation and then they would leave it.
JOYCE: And the snakes knew that.
Mr. JASON HEAD (University of Toronto): "Anaconda" meets "Jurassic Park."
JOYCE: That's Jason Head, a paleontologist at the University of Toronto, who worked with Wilson's team.
Mr. HEAD: These sauropods would lay these huge fields of eggs, kind of kilometers of dinosaur eggshell, and so with these hatchling dinosaurs it must have just been a smorgasbord where an ecosystem of predators could basically come in and feed on them.
JOYCE: In this case, a sudden avalanche of sand or mud must have intervened and buried both prey and predator like entombed Romans at Pompeii.
The scientists call the snake�Sanajeh indicus.�It did not have a modern snake's jaw, which basically unhinges so the snake can swallow large prey, but instead had a jaw more like a lizard. Head says the snake probably made up for that by growing very large. So did the sauropods, which probably grew very fast as well, given their apparent tastiness.
The discovery is described in the journal�PLOS Biology.
Christopher Joyce, NPR News.