Paleontologists study life forms, like dinosaurs, that were alive millions of years ago. The writings of paleontologist Brian Switek prove that even though his subjects are ancient, the thinking in his field is constantly evolving.
A few examples:
An asteroid killed the dinosaurs, right?
Switek writes: "That's a nice fairy tale. But it's not accurate. It's more of the 'based on a true story' version of what really happened as the curtain fell on the Cretaceous ... Over the past few years, paleontologists have been revising their view of what actually happened during one of the five worst extinctions of Earth's history."
When did dinosaurs evolve into birds?
Switek writes: "Birds are a special lineage of coelurosaurian dinosaurs. That is a fact. But the details of when and how that transition occurred, not to mention exactly from whom, are still areas of active debate."
Is "Jurassic Park," which is back in theaters, still on the cutting edge of paleontological thought?
Switek writes: "'Jurassic Park' is also a time capsule of dinosaurs circa 1993 which misguided, diehard fans regard as immutable canon. The film's dinosaurs have become so entrenched in the public imagination that there is much weeping, wailing, and gnashing of teeth at the suggestion that maybe the fourth film in the series — set to debut sometime next year — should again mix the best of science and imagination by featuring feathery, bird-like dinosaurs."
Switek's new book, "My Beloved Brontosaurus," provides a primer on the latest thinking on dinosaurs from someone who has loved and been fascinated by the creatures for years.
THE TAKEAWAY: Forget about a real-life "Jurassic Park."
Switek told Kerri Miller said he was a fan of "Jurassic Park," the 1993 Steven Spielberg movie about a project to clone dinosaurs from ancient DNA. "Even after 20 years, it's still probably the most fantastic and scariest dinosaur film ever made," he said.
The film has been rereleased in 3D, and Switek "actually saw it the other night with a group of paleontologists from the Natural History Museum of Utah ... I first saw it when I was 10. It was fantastic to sit there again and see these dinosaurs larger than life, back on the screen." It's not always realistic, he said, but "most of the time, it's the closest I might ever get to seeing some of these dinosaurs actually in the flesh. ... It literally gave me chills."
But he extinguished any hope that we might ever see the real thing.
"I'm really sorry to say this, but we're never ever going to clone a prehistoric dinosaur," Switek said. "And the reason for that is DNA actually has a half-life. ... It takes about 521 years for about half the amount of existing DNA to disappear. So after about 6 million years, an animal's entire genome is going to be gone. And since the last non-avian dinosaurs died out 66 million years ago, that's far too short. And without DNA, we can't clone Velociraptor, Brachiosaurus or any of the other charismatic species ...
"We're disappointed by that, and maybe a little bit glad, given what happened in 'Jurassic Park.'"
Laelaps: Brian Switek's blog for National Geographic
Everything You Wanted to Know About Dinosaur Sex. Switek for the Smithsonian: "Dinosaurs must have mated, but just how they did so has puzzled paleontologists for more than 100 years."