3-Million-Year-Old Skeleton Gets CT Scan
JACKI LYDEN, Host:
Now, to someone who's been dead for more than 3 million years. Her name is Lucy and, of course, she's an old fossil, the most famous in the world. Scientists have studied her skeleton for decades, and she's provided many answers about human ancestry, but Lucy still has some 'splainin' to do.
(Soundbite of TV show, "I Love Lucy")
Mr. DESI ARNAZ: Lucy!
LYDEN: It's "Science Out of the Box."
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LYDEN: This Lucy is from Ethiopia but right now, she's hanging out in Seattle at the Pacific Science Center. It's her second stop on a tour across the United States and during her trip, scientists took the opportunity to give her a high-resolution CT-scan. Jonathan Kappelman is an anthropology professor at the University of Texas. He led the team that scanned Lucy. He says the process they used, a CT-scan, is much more powerful than a medical CAT-scan that we might take. And there's another big difference.
Dr. JONATHAN KAPPELMAN (Professor of Anthropology, University of Texas): So, if you look at the medical CAT-scans, that's C-A-T, and the "A" in there means axial. The machine swings around us when we're lying on the bed there inside the scanner. Our specimens, they actually sit on a little turntable and rotate around the X-ray source and the detector. And that's because if we rotated us around, we'd get motion sick when we were being scanned.
LYDEN: I gather there was an Ethiopian person who did handle the fossil. Can you talk about him a little bit?
Dr. KAPPELMAN: Oh, sure. This is Ato Alamieu(ph). He's been Lucy's handler, so to speak for - well, probably about the last 20 years or so, and he's the only person who's permitted to touch the fossil. So, we could help him direct the placement of the fossil into the special foam mounts that we've constructed for the scanning. But Alamieu does all of the mounting of the specimen both, say in the exhibits when she goes up on exhibit, he's the one who puts her on the exhibit. He takes the exhibit down, and he's the main person in charge there.
LYDEN: What were you looking for that you haven't known before, and why were you so keen to do this type of scan in the first place?
Dr. KAPPELMAN: Here, we're looking at a form of species that was clearly bipedal when she was on the ground, but there are other aspects of her skeleton that have always been a little bit of an enigma to people.
Dr. KAPPELMAN: For example, that within her species, we see curved fingers and toes. We see an upper shoulder joint that points a little bit more overhead than it does out to the side. Those are all attributes that suggest arboreal behavior.
LYDEN: That she - basically a tree-climber and lived in trees.
Dr. KAPPELMAN: She might have been climbing in the trees. Now, we don't know how much of that - and some people have argued, oh, these are just primitive retentions. They don't tell us anything about her actual behavior. But because the skeleton responds dynamically, that it's very economic in the way that it invests bone. A bone isn't used, it gets rid of that bone if it's not necessary to insure the integrity of the skeleton. And this is going to be really the first time that we've been able to look at this question in detail.
LYDEN: Jon Kappelman is an anthropology professor at the University of Texas in Austin. Thank you so much for joining us.
Dr. KAPPELMAN: Thanks for your interest.
LYDEN: Before we move on, it turns out that in this economy, even 3-million-year-old fossils are having a tough time. When Lucy made her first U.S. stop in Houston, she was a hit. But then, she moved to Seattle just in time for the economic crisis. An adult ticket to see her costs about 20 bucks, and sales have been weak. Lucy's lease in Seattle runs out March 8. And it's not clear where she lands next. Up next: stellar animation on screen, heart-rending drama on stage, and still singing the blues at 95. This is NPR News.