ADDIS ABABA, Ethiopia – After 3.2 million years in East Africa, one of the world's most famous set of fossils was quietly flown out of Ethiopia overnight for a U.S. tour that some experts say is a dangerous gamble with an irreplaceable relic.
Although the fossil known as Lucy had been expected to leave the Ethiopian Natural History Museum this month, some in the nation's capital were surprised the departure took place under cover of darkness with no fanfare Sunday.
"This is a national treasure," said Kine Arega, a 29-year-old attorney in Addis Ababa. "How come the public has no inkling about this? It's amazing that we didn't even get to say goodbye."
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Paleontologist Berhane Assaw said he arrived at the museum Monday morning after working late Sunday night to find that the fossil and key staff members had left for Texas, where Lucy will go on display this month.
The departure "should have been made public," he said.
The Smithsonian Institution has objected to the six-year tour because museum experts do not believe the fragile remains should travel. Even in Ethiopia, the public has seen the real Lucy fossil only twice.
The Lucy exhibition at the Ethiopian Natural History Museum is a replica, and the real remains are usually locked in a vault to protect them.
"Quite simply, the Smithsonian position is that the fossil Lucy, one of the most important specimens of its kind, is too fragile to go on public tour," National Natural History Museum spokesman Randall Kremer said Monday.
The curator of anthropology at the Houston Museum of Natural Science, where Lucy will be on display from Aug. 31 to April 20, said he shared the Smithsonian's concern over ensuring the security of artifacts on display. But he said this should not preclude them from traveling.
"We will put Lucy on display with the utmost care just as we have put other fragile artifacts on display, such as the Dead Sea Scrolls, which were returned to Israel in the same condition they came to our museum," Dirk Van Tuerenhout said.
The museum exhibited the Dead Sea Scrolls for three months in late 2004 and early 2005.
The fossilized partial skeleton of what was once a 3½-foot-tall adult of an ape-man species was discovered in 1974 by U.S. paleontologists Donald Johanson and Tom Gray in the remote, desert-like Afar region in northeastern Ethiopia.
Lucy is classified as an Australopithecus afarensis, which lived in Africa between about 3-4 million years ago, and is the earliest known hominid.
Most scientists believe Australopithecus afarensis stood upright and walked on two feet, but they argue about whether it had ape-like agility in trees. The loss of that ability would suggest crossing a threshold toward a more human existence.
Lucy's name was taken from a Beatles song that played in an archaeological camp the night of her discovery.
Paleontologist Leonard Krishtalka, director of the Natural History Museum at the University of Kansas, said the most dangerous risk of damage to Lucy would be from exposure to hazardous light levels while on display.
"There's no question that there are dangers while Lucy travels around the country, but museums ship valuable specimens around the world all the time. The question is, is the risk enough not to allow the public to see this treasure?" he said.
Ethiopian government officials have said that they will use the money raised from the traveling exhibit to improve museums and build new ones in Ethiopia, one of the world's poorest countries. Officials have declined to say how much they spent to insure Lucy or how much the government was being paid for the tour.
But some don't believe the money is an important enough reason to allow the remains to leave the country.
"Money cannot be a justification to export original specimens," said Zelalem Assefa, an Ethiopian who works at the Smithsonian and was visiting Addis Ababa. "These are original, irreplaceable materials. These are things you don't gamble with."
Ethiopia's culture minister, Mahamouda Ahmed Gaas, declined to comment on the tour Monday.
Other Lucy stops in the U.S. have yet to be finalized, but Ethiopian officials have said they include New York, Denver and Chicago.
The fossil is tentatively scheduled to be exhibited at The Field Museum in Chicago from November 2009 through April 2010, according to spokeswoman Nancy O'Shea. However, details have yet to be worked out, and no contract has been signed, she said.
Laura Holtman, a spokeswoman for the Denver Museum of Nature and Science, said the museum has had discussions about hosting the exhibit, but has not made a final decision.
She said it will require more work to set up than most traveling displays, and officials are also considering the ethical issues that have been raised about exhibiting the Lucy remains.
"We haven't ruled it out," Holtman said. "Certainly, it's an amazing opportunity."