In 2000, members of a Judith River Dinosaur Institute expedition found a fossil -- a 77-million-year-old duckbill dinosaur, more officially known as Brachylophosaurus canadensis. The team named the specimen Leonardo after some nearby graffiti: "Leonard Webb loves Geneva Jordan 1916." Leonardo wasn't full-grown -- it was probably only 3 or 4 years old when it died.
Dinosaur Image Gallery
Leonardo's body was embedded high in a canyon wall in Montana. Twenty diggers worked for more than nine weeks to remove the rock from around the fossil, and they had some high-powered help. A demolition crew used explosives to free the entire, 18-foot (5.5-meter) piece of stone from the cliff. This chunk weighed 6.5 tons (5.9 metric tons) or about as much as five Mini Coopers [source: The Leonardo Project]. When researchers had to ship Leonardo for analysis, they insured it for $2.5 million. And when it was time to plan Leonardo's world museum tour, Ford Motor Company used rapid prototyping to make a full-scale, 3-D model to send in its place [source: Ford].
Why go to so much trouble and expense for a fossil? Paleontologists haven't uncovered many Brachylophosaurus canadensis skeletons, but the species' rarity is a just a fraction of Leonardo's importance. Unlike almost all unearthed dinosaur fossils, Leonardo still has skin. The skin isn't soft and supple like that of living animals. It's been fossilized, just like the bones.
Leonardo's now-stony skin also protected its internal organs, from its heart to the contents of its stomach. So when paleontologists study Leonardo, they're not just looking at a skeleton. They're looking at a whole body. Examining this body could provide as much information about dinosaurs as autopsies can about humans.
But there's a catch. Performing a traditional autopsy on Leonardo would destroy the fossil. So, the researchers behind the Leonardo Project have gone to great lengths to examine Leonardo's insides from the outside -- noninvasively.
Mummified Dinosaur Fossils
In spite of its exceptional preservation, Leonardo became a fossil in the usual way. Sediment buried its body, and minerals slowly replaced its tissues. But something about Leonardo's burial was different. Typically, soft tissues like skin, muscle and cartilage decay long before fossilization can take place. In Leonardo's case, something -- perhaps a thick layer of wet sediment -- protected the body from the scavengers and bacteria that break down soft tissue. His skin and internal organs lasted long enough to turn to stone.
This turned Leonardo into one of a handful of mummified dinosaur fossils. At the time of its discovery, Leonardo was one of only four mummified dinosaurs ever found [source: Mayell]. This rarity made studying the fossil without destroying it extremely important.
To do this, researchers relied on one of the same tools doctors use to study human bodies without cutting them -- X-ray imaging. The team used a digital imager to take more than 40 X-rays of Leonardo's head and body. This gave the team a glimpse of what was inside. But to get enough definition of the rock-on-rock organs to really see what went where, the researchers needed a more powerful radiation source than they could use in their building. They took Leonardo to a hangar at Johnson Space Center Ellington Field in Houston, Texas. That's when Leonardo got its $2.5-million insurance policy. At the Ellington Field facility, researchers used highly radioactive isotopes to get a look at the structures deep within Leonardo's body.
All these X-rays have added up to a life-size, 3-D view of Leonardo's organs. Some of the findings are:
- Evidence of a birdlike crop, used to predigest food, in Leonardo's neck
- Images of its heart and liver
- Evidence that the dinosaur was bitten by a large predator shortly before its death
Leonardo is so well-preserved that researchers have even figured out what it ate. Inside its digestive system are:
This is a lot of information to come from one fossil, which is why Leonardo has gotten lots of media attention. A Discovery Channel special called "Secrets of the Dinosaur Mummy" documents researchers' work with the fossil. And because of its remarkable state of preservation, Leonardo is recognized in the Guinness Book of World Records as the best preserved dinosaur. But Leonardo isn't just a media event -- it's also a major scientific discovery. Research is ongoing, so Leonardo may yield new information in the future.
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More Great Links
- American Museum of Natural History. "Dinosaur Mummy." (8/20/2008) http://www.amnh.org/exhibitions/expeditions/treasure_fossil/Treasures/Dinosaur_Mummy/mummy.html?50
- "Brachylophosaurus Leonardo." Judith River Dinosaur Institute. (8/20/2008) http://www.montanadinosaurdigs.com/
- Carestream Health. "Digital X-ray Technology Opens our Eyes to Prehistoric Life." Press release. (8/20/2008) http://pw.carestreamhealth.com/en/eknec/documents/LeonardoProject.pdf
- Chin, Karen. "Gut Check." EurekAlert! press release. 10/23/2006 (8/20/2008) http://www.eurekalert.org/pub_releases/2006-10/uoca-gc102306.php
- Ford Motor Company. "Dinosaur Fossil is One-of-a-kind Model from Ford." Press release. 7/7/2008 (8/20/2008) http://www.ford.com/about-ford/news-announcements/press-releases/ press-releases-detail/pr-dinosaur-fossil-is-oneofakind-28596
- Houston Museum of Natural Science. "World Premiere of 'Mummified' Dinosaur Comes to Houston." Press release. (8/20/2008 http://www.hmnspress.org/Press_FullStory.aspx?contentid=200
- Iacuzzo, Joe. Project Manager, The Leonardo Project. Personal interview conducted 8/15/2008.
- Iacuzzo, Joe. Project Manager, The Leonardo Project. Personal interview conducted 8/19/2008.
- Mayell, Hillary. "'Mummified" Dinosaur Discovered in Montana." National Geographic News. 10/11/2002 (8/20/2008) http://news.nationalgeographic.com/news/2002/10/1010_021010_dinomummy.html
- Roach, John. "'Dinosaur Mummy' Found: Has Intact Skin, Tissue." National Geographic News. 12/3/2007 (8/20/2008) http://www.eurekalert.org/pub_releases/2006-10/uoca-gc102306.php
- "Secrets of the Dinosaur Mummy." Dir. Michael Jorgensen. Myth Merchant Films/Discovery Channel. 2008.
- The Leonardo Project.(8/20/2008) http://www.mummydinosaur.com/