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AUDIE CORNISH, HOST:
It was as long as two trucks with a trailer, each one in front of the other. It weighed as much as 14 elephants. That's the claim from researchers in Argentina's paleontology museum about the latest fossil find in the so-called Titanosaur family, of course. Scientists say they've dug up the largest thigh bone ever found and they think they're on to a whole skeleton.
But this isn't the first time that a big fossil find have led researchers to tout the largest-ever dinosaur. There was the Supersaurus found in 1972, fossils dubbed Ultrasaurus in 1983, and then there was the Seismosaurus in 1991.
Brian Switek says there is reason to be cautious about the claims of this latest find. And he's a science writer and author of "My Beloved Brontosaurus: On The Road With Old Bones, New Science And Our Favorite Dinosaurs." He joins us now.
Welcome to the program, Brian.
BRIAN SWITEK: Thanks for having me.
CORNISH: So tell us more about these particular bones, this newest find. I understand its in an area that's been dubbed a kind of dinosaur cemetery.
SWITEK: Absolutely, what's really cool about this new site is that they've got about 150 bones from seven different individuals. So this isn't just one dinosaur that died in one spot. You have a group, perhaps a social group, perhaps a family of dinosaurs that all got buried together. So to have that much information, sort of about, you know, perhaps growth and size and maybe even behavior from the site is, you know, quite exciting.
CORNISH: But given what you've said about this being an area with all kinds of, is it too early to tell whether the claims that this could potentially be the biggest creature to walk the Earth, that those are true?
SWITEK: Yeah, everybody wants to have a piece of that superlative, you know, Largest Animal To Ever Work The Earth. It's a bit too early to tell, so the measurement so far, under 30 feet long and 77 tons, those are only estimates coming off of a single thighbone or femur. And that's compared to other sort of more complete dinosaurs that have been found before, sort of scaling up, to get an idea based on previous estimates. So it's kind of estimates on estimates.
CORNISH: And we mentioned the Supersaurus and the Ultrasaurus, I mean what happened to these previous titleholders, these finds that were also claiming to be the largest or the longest ever?
SWITEK: Many of them were knocked down. I'm happy to say that Supersaurus is still around, that one is still valid. This was a rather graceful giant, 110 feet long estimated about 45 tons. But some of these other ones, like Ultrasaurus, that turned to be parts of Supersaurus and another dinosaur that had gotten mixed together in the same quarry, so that name is discarded.
CORNISH: What are we learning from this kind of research about what limits there are, in terms of how big an animal can get?
SWITEK: Well, that's the really neat thing about this new dinosaur is that the competition is so close. This isn't something that would absolutely blow all the other dinosaurs away, even if it was about 130 feet long. So what this sort of size range says is the fact that we have multiple, giant dinosaur species, that are clustering around 100 foot, 50 ton or so range, might suggest that that's basically as big as it's possibly can get.
That this sort of biological systems needed to support an animal that size might have been reaching their limits, in terms of the just the amount of food the animal might have been able to eat. And in terms of some physiological things, like sort of nerve conduction, that you have a neck that's 45 feet long with a certain nerve, and they call it the recurrent laryngeal nerve, that goes from the brain all the way down the neck around the aortic (unintelligible) of the heart and all the way back into the throat.
So, you have 90 feet of nerve in a 45 foot long neck that needs to send signals back and forth. It might be that, you know, these dinosaurs were getting too big to basically have effective communication within their own bodies.
CORNISH: In the meantime, any ideas for nickname...
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CORNISH: ...for this latest find?
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SWITEK: It's hard to say. We've already had ultra and super and...
CORNISH: Godzilla, will that work?
SWITEK: I think that would work, yeah. It certainly is superlative...
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SWITEK: ...animal that pushed the boundaries of science.
CORNISH: Brian Switek, he's the author of "My Beloved Brontosaurus: On The Road With Old Bones, New Science And Our Favorite Dinosaurs."
Thanks so much for talking with us.
SWITEK: It's been a pleasure, thank you.
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