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During the restoration work over the winter that included installing a new trail, fossilized black bear remains in limestone were discovered, Roth said. The trail was routed around the bones, which are now on exhibit. Grizzly find -- oldest ever -- puts caves in spotlight Fossils could be 50,000 years old, raising questions BY PAUL FATTIG CAVE JUNCTION -- Scientific research deep in the dark recesses of the Oregon Caves National Monument is shedding light on Ice Age mysteries. Fossilized grizzly bones unearthed in the caverns some 20 miles east of Cave Junction are the oldest ever uncovered in North America, forcing scientists to take another look at the timeline when the huge beasts first ambled about the continent. "From what has been found in the Oregon Caves, it appears grizzlies may have been here 50,000 years ago," said Jim Mead, a paleontologist with the Department of Geology at Northern Arizona University. "That's a ballpark figure. But, even if it's a little wrong, it's so much earlier than any grizzly bear ever found. "We want to double-check everything," he added of continuing research. "But we certainly have a lot of thinking to do about what all this means." What it may mean is that the grizzlies didn't arrive some 12,000 years ago as previously thought, based on earlier fossil evidence, he said. "We're not finding anything directly about humans, but if you have the door open that allows bears to do things, then other animals, including humans, could also do them," he said. He was referring to the long-held theory that humans migrated across an ancient land bridge from what is now Siberia into North America. However, that theory holds that humans made the crossing some 40,000 years ago, long after the grizzly bones fossilized in the caves. "It was once thought that glaciers blocked the grizzly from moving down into the area that long ago, but now it appears there was an ice-free zone along the coast," explained John Roth, resource manager at the Oregon Caves. "It looks like a good possibility they were moving down along the coast." The research is putting the Oregon Caves on the paleontology map, he said. The grizzly fossils were found in 1997 by a team mapping the far interior of the cave. In 1995, their fossil finds included an enormous jaguar. The remains of the 450- to 500-pound animal were believed to be more than 20,000 years old. Carbon-14 dating, which measures the amount of carbon remaining in an object, has been used to date the fossils, Mead said. Carbon takes about 50,000 years to break down, leading to the conclusion about the fossil's age. During the restoration work over the winter that included installing a new trail, fossilized black bear remains in limestone were discovered, Roth said. The trail was routed around the bones, which are now on exhibit. However, the grizzly bones, which include a thigh, skull and other bones, are at Northern Arizona University. Mead, whose specializes in cave fossils, is working on the project with Greg McDonald, a National Park Service paleontologist based at the Hagerman Fossil Beds National Monument near Twin Falls, Idaho. The area where the fossils have been found is a remote site along the River Styx, the small stream that bubbles out of the cave. The finds are resulting in more questions than answers, Mead said. "We do know for sure that we have very old grizzly bones," he said. "Until now, we thought they were a relatively recent introduction into North America from Siberia and Asia. "It's very exciting," he added. "Everybody likes big things, especially big bears. But if you really want to know about past environments, you want the little critters." For that reason, Mead and the researchers are looking at what may have scurried around the huge feet of the grizzly. The researchers, who plan to return this summer, have been sifting through the ancient sediment in the caves. They have found fossilized remains of several small creatures, including what is commonly called the mountain beaver. "Everything points to fact the Oregon Caves could hold more unique records," he said. "One thing we want to get a handle on is when the Oregon Coast got all those little salamanders. The caves should be able to tell us." Some of the most ancient sediment in the caves is believed to be more than 110,000 years old, he said. "The Oregon Caves are going to help us figure out a lot of things," he predicted. The cave was discovered in November 1874 by Williams Valley resident Elijah Davidson, a bear hunter whose dog chased a bear into the entrance. However, the bruin was a black bear, not a grizzly, Davidson reported. Mail Tribune Copyright � The Mail Tribune 1999, Medford, Oregon USA