An artist's model of the Montana Dueling Dinosaurs based on geographical placement of the fossils.

An artist's model of the Montana Dueling Dinosaurs based on geographical placement of the fossils. (Image: Black Hills Institute of Geological Research Inc and Katie Busch/CK Preparations)

NEW YORK — Discovered side-by-side in the Montana badlands, two fossilized dinosaurs failed to sell at auction here on Tuesday, Nov. 19, in a packed room of prospective buyers, curious onlookers and reporters.

Bonhams auction house, which handled the sale of the so-called Dueling Dinosaurs, had estimated the creatures would sell for between $7 million $9 million. Bidding started at $3 million and stopped at $5.5 million, however, failing to meet the auction house's reserve.

So for now at least, the famed T. rex called Sue remains the most expensive fossil specimen to be sold at public auction. The Field Museum in Chicago bought that dinosaur in 1997 for $8.36 million, blowing away expectations at the time that it would sell for around $1 million. [See Images of the Dueling Dinosaur Fossils]

The auction house is hopeful the dinosaur duo along with other fossils that didn't sell today will find homes. "I am very confident that we're going to find scientific homes" for the fossils that didn't sell, said Thomas Lindgren, co-consulting director of the natural history department at Bonhams in Los Angeles, who put together the natural history auction. Lindgren added that several U.S. institutions are interested in buying the Dueling Dinosaurs. "Those negotiations will begin immediately," he said.

Locked in the same chunk of earth, the two dinosaurs were being auctioned off as a single specimen, still encased in dirt and their plaster field jackets.

Some paleontologists had expressed fears ahead of the auction that the dinosaurs could be lost to science should they end up in the hands of a private collector who has no desire to loan or donate them to a public institution.

Fossil hunters uncovered the massive herbivore and the meat-eater on a ranch in the Montana badlands in 2006. The beasts' poses suggest they were engaged in mortal combat, and hence the nickname of the Dueling Dinosaurs.

Billed as the most complete dinosaur fossils from North America's Late Cretaceous rocks, the Dueling Dinosaurs are extremely well articulated and bits of skin even cling to the sand that surrounds the bones.

The creatures in question are a ceratopsid — perhaps a new species of Triceratops — and a tyrannosaurid — possibly a Nanotyrannus lancensis, according to Bonhams.

Researchers are often loathe to put a price tag on their study specimens, and some objected to the sale on scientific grounds, arguing that the fossils' true importance, identity and death saga (i.e., whether they represent fierce combatants or perhaps a pair of unlucky strangers washed away in a flood) cannot be known until the bones are examined in peer-reviewed studies.  

The fossils previously had been offered to museums in the United States, but they were turned down because of the prohibitive price. Hans-Dieter Sues, curator of vertebrate paleontology at the Smithsonian's National Museum of Natural History, told LiveScience earlier this month that his institution was offered the fossils for $15 million.

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