For Immediate Release Media contacts: The Field Museum Greg Borzo 312/665-7106 gborzo@fieldmuseum.org This new method of estimating land elevation has an average error of about 980 feet (300 meters) – but as low as 330 feet (100 meters). Such an error rate is much lower than the error rate of existing paleoelevation methods, all of which have significant limitations. This method can be used for any area where suitable plant specimens can be found. High mountains and plateaus can act as important barriers to plant and animal migration and dispersal resulting in isolation of plant and animal populations on opposite sides of mountain chains. Therefore, knowing exactly when in the geological past the mountains of today’s world reached their current elevations is relevant to our understanding of plant and animal evolution since isolation is an important mechanism in the formation of species. In addition, high mountains and large plateaus (such as those in Tibet and Colorado today) have always had a big influence on climate by altering patterns of atmospheric circulation. Because this new method is independent of variations in climate, it will allow scientists to identify the impact of elevation on global climate patterns and factor elevation into the study of global climate change. This research also highlights the importance of museum collections, Dr. McElwain noted. “You never know what information is locked up in specimens or artifacts kept at a natural history museum like ours until someone develops a new method, tool or technology to draw out those secrets.” The Field Museum houses more than 23 million specimens and artifacts from around the world – everything from mushrooms to meteorites and mummies to man-eating lions. Everyday, it adds an average of 500 objects to its vast collections. Digital images available: Images available as 300 dpi tif files. To download these image files, click on the thumbnail image to download the larger file. image size: 5.5 mb Magnified leaf, showing hairs Image of the surface of a California Black Oak leaf magnified 400 times showing epidermal cells, hairs and stomata, which look like grains of barley. The density of the stomata can be used to estimate how high mountains were in the geological past. Photo by Jennifer McElwain, courtesy of The Field Museum image size: 6 mb Old and new leaves A 15-million-year-old fossil California Black Oak leaf, on loan from the Paleontological Museum Berkeley to the Field Museum, surrounded by modern California Black Oak leaves. Photo by John Weinstein, courtesy of The Field Museum image size: 6.3 mb Sprig of leaves Image of a dried California Black Oak leaf collected with permission from Mount Star King in Yosemite National Park at an elevation of about 7,000 feet. The leaves are much smaller at higher elevations, in this case about an inch long. Photo by John Weinstein, courtesy of The Field Museum <<Back to the Press Room