Paleontologists are preparing to revisit one of North America's most remarkable troves of late Pleistocene fossils from the Pleistocene era, for the first time in 30 years.
Natural Trap Cave in north-central Wyoming is 85 feet deep and close to impossible to see until you're standing right near it, according to the Associated Press. Over the course of tens of thousands of years, a number of animals, including extinct mammoths, American lions, and American cheetahs, plunged to their deaths because they didn't notice the 15-foot-wide opening.
The U.S. Bureau of Land Management is now preparing to reopen the metal grate over the opening to provide scientists the chance to look at the critters that roamed the foothills of the Bighorn Mountains during the planet's last glacial period around 25,000 years ago.
Des Moines University paleontologist Julie Meachen said she has been preparing to lead the international team of a dozen researchers and assistants by hitting the climbing gym.
"I'm pretty terrified," Meachen said, according to the Associated Press.
While she hasn't done any real climbing before, she said the only way in is to rappel down. The only way out is an eight-story, single-rope, and climb all the way up.
The cave is cold and clammy, with temperatures in the mid-40s and humidity around 98 percent.
"It's so cold all year long, that it has got just the perfect conditions for preserving DNA, in multiple species, in large numbers of individuals," Meachen said. "Which is not really found anywhere except Siberia and the Arctic."
Bureau of Land Management regional paleontologist Brent Breithaupt, who isn't afraid of seeing lots of animal bones, said the cave is a bit creepy.
"One can only hope that, as a researcher, you're able to leave," said Breithaupt, who visited the cave as a college student the last time it was open to scientists, according to AP. "It's an imposing hole in the ground. But one that actually has very important scientific value."
It is believed that some mammal remains from the cave are over 100,000 years old, according to Breithaupt.
The Bureau of Land Management installed the grate to keep people and animals out in the 1970s.
On July 28, scientists will re-explore the cavern, dig and extract as many fossils over a two-week period as they can.
Additional excavations in 2015 and 2016 will be funded by the National Science Foundation.
"I don't think it's necessarily going to be easy," she said. "But I think we're going to be pretty well prepared."
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