Live Breaking News & Updates on Chengyu Weng

This article originally appeared on Undark.
The first and only time Steve Jackson spoke to Bill Critchfield was in the late 1980s. Critchfield, an authority on the conifers of North America, was at home recovering from a heart attack. Jackson, then a postdoctoral researcher at Brown University, had called looking for advice on how to tell jack pine from Virginia pine.
Jackson was also curious about something the elder botanist had mentioned in a recent paper: mysterious spruce fossils from the American Southeast. The fossils dated to the end of the Pleistocene ice age, about 18,000 years ago, and had been found across the region, including in Louisiana s Tunica Hills. Scientists had usually identified the fossils as white spruce, a species that now lives far to the north, but they d been arguing for decades about what its presence said about the region s ice age climate. Some held that white spruce pointed to a climate similar to modern Canada or Alaska. Others argued tha ....

United States , United Kingdom , University Of Cincinnati , Tunica Hills , Gulf Of Mexico , Little Bayou Sara , University Of Miami , Paul Martin , Emma Lucy Braun , Charles Darwin , Alaskan Arctic , Chengyu Weng , Steve Jackson , Jacquelyn Gill , Laura Parducci , Tim Temizy , Edward Deevey , Paul Delcourt , Hazel Delcourt , Illinois State Museum , Northern Arizona University , Tongji University , Sapienza University Of Rome , Louisiana State University , Brown University , National University Of Colombia At Medell ,