Lost Cause
It's a wrap!
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- Oct 7, 2001
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This is such an unusual find, I thought some of you would appreciate the rarity and significance of "Leonardo."
“We have a (fossilized) cadaver or a corpse, and we’re experiencing ‘CSI,’” he said, referring to the TV detective drama. “It’s a real crime investigation.”
Only three other mummified dinosaur fossils are known to exist, the researchers said.
Mummified fossils have turned to minerals in such a way that they preserve the look of the skin and internal tissue. In the past, scientists have theorized that mummified dinosaur flesh was dried out before it became a fossil. But Murphy and his fellow researchers believe Leonardo took a different path to posterity.
“We think that it was buried in wet river sand around 77 million years ago, and much of the flesh was intact when fossilization started,” said Dave Trexler, paleontologist with Timescale Adventures. “The pollen from its stomach also shows that the environment was too wet for much desiccation to take place before burial.”
Geologist Mark Thompson of the Judith River Dinosaur Institute said “a very rare sequence of events was necessary for this type of preservation to occur. ... It is a once-in-a-lifetime find.”
Volunteer fossil hunter Dan Stephenson spotted the first exposed traces of the two-ton, 23-foot-long (7-meter-long) specimen in a sandstone deposit during an institute expedition in the summer of 2000. He dubbed the fossil Leonardo after observing the name “Leonard” carved in a sandstone rock, with the date 1916, near the site of the discovery.
Paleontologists say Leonardo was a brachylophosaurus — a type of duckbill dinosaur, or hadrosaur. The rock layer where the fossil was found has been dated back 77 million years, to the Late Cretaceous period, Murphy said.
An analysis of the fossilized bone structure led researchers to conclude that Leonardo was a subadult that died when it was about 3 or 4 years old. “It still had what we call the ‘cute factor,’” he said.
The fossil features a three-dimensional rock cast of the right shoulder muscle and throat tissue, along with traces of the skin, toenails, beak and internal organs. The impression reveals that the skin had scales that vary from the size of a BB to the size of a dime, Murphy said — with the larger scales covering the forearms as well as the shins.
“Those scales served a little bit like armor,” he said. “The large scales would actually protect the legs better. ... Your lower legs are going to take a beating.”
The well-developed muscles of the shoulder and the forearm led Murphy to conclude that duckbills may have used their front legs more than previously thought.
“It’s a huge muscle that’s actually preserved there. If you’re mostly bipedal, that’s a waste,” he said. That led Murphy to speculate that duckbill dinosaurs walked on all fours more than some paleontologists had thought.
Leonardo had a “very big, robust neck,” Murphy said, with what appears to be a gular pouch — a patch of loose skin hanging down from the beak.
Within the fossilized stomach, researchers reportedly could make out shapes from Leonardo’s last lunch: ferns, conifers and a magnolia-type plant.
Murphy said paleontologists at the Oklahoma meeting were anxious to learn more about Leonardo, and that the specimen would be subjected to far more study — including, Murphy hopes, a computerized scan of the fossil’s internal structures. “Once we get that back, who knows what else we’ll learn about what’s inside his chest cavity,” he said. “Maybe we can settle this whole debate about cold- or warm-blooded.”
“We have a (fossilized) cadaver or a corpse, and we’re experiencing ‘CSI,’” he said, referring to the TV detective drama. “It’s a real crime investigation.”
Only three other mummified dinosaur fossils are known to exist, the researchers said.
Mummified fossils have turned to minerals in such a way that they preserve the look of the skin and internal tissue. In the past, scientists have theorized that mummified dinosaur flesh was dried out before it became a fossil. But Murphy and his fellow researchers believe Leonardo took a different path to posterity.
“We think that it was buried in wet river sand around 77 million years ago, and much of the flesh was intact when fossilization started,” said Dave Trexler, paleontologist with Timescale Adventures. “The pollen from its stomach also shows that the environment was too wet for much desiccation to take place before burial.”
Geologist Mark Thompson of the Judith River Dinosaur Institute said “a very rare sequence of events was necessary for this type of preservation to occur. ... It is a once-in-a-lifetime find.”
Volunteer fossil hunter Dan Stephenson spotted the first exposed traces of the two-ton, 23-foot-long (7-meter-long) specimen in a sandstone deposit during an institute expedition in the summer of 2000. He dubbed the fossil Leonardo after observing the name “Leonard” carved in a sandstone rock, with the date 1916, near the site of the discovery.
Paleontologists say Leonardo was a brachylophosaurus — a type of duckbill dinosaur, or hadrosaur. The rock layer where the fossil was found has been dated back 77 million years, to the Late Cretaceous period, Murphy said.
An analysis of the fossilized bone structure led researchers to conclude that Leonardo was a subadult that died when it was about 3 or 4 years old. “It still had what we call the ‘cute factor,’” he said.
The fossil features a three-dimensional rock cast of the right shoulder muscle and throat tissue, along with traces of the skin, toenails, beak and internal organs. The impression reveals that the skin had scales that vary from the size of a BB to the size of a dime, Murphy said — with the larger scales covering the forearms as well as the shins.
“Those scales served a little bit like armor,” he said. “The large scales would actually protect the legs better. ... Your lower legs are going to take a beating.”
The well-developed muscles of the shoulder and the forearm led Murphy to conclude that duckbills may have used their front legs more than previously thought.
“It’s a huge muscle that’s actually preserved there. If you’re mostly bipedal, that’s a waste,” he said. That led Murphy to speculate that duckbill dinosaurs walked on all fours more than some paleontologists had thought.
Leonardo had a “very big, robust neck,” Murphy said, with what appears to be a gular pouch — a patch of loose skin hanging down from the beak.
Within the fossilized stomach, researchers reportedly could make out shapes from Leonardo’s last lunch: ferns, conifers and a magnolia-type plant.
Murphy said paleontologists at the Oklahoma meeting were anxious to learn more about Leonardo, and that the specimen would be subjected to far more study — including, Murphy hopes, a computerized scan of the fossil’s internal structures. “Once we get that back, who knows what else we’ll learn about what’s inside his chest cavity,” he said. “Maybe we can settle this whole debate about cold- or warm-blooded.”
