Montana State University scientists say the frozen remnants of an ancient forest discovered 600 feet above the modern tree line on the Beartooth Plateau may portend possible changes for the alpine ecosystem if the climate continues to warm. A paper about the discovery is published in the journal Proceedings of the National Academy of Sciences. It describes what scientists have learned by studying the remains of a mature whitebark pine forest that formed at 10,000 feet elevation about 6,000 years ago, when warm-season temperatures in the Greater Yellowstone Ecosystem were similar to those of the mid-to-late 20th century… The results of the study suggest current climate conditions could lead to trees moving upslope into areas of the plateau that are now tundra.