The new paper is part of an ongoing research effort that began in 2018, when Smithsonian researchers were helping develop the museum’s "David H Koch Hall of Fossils—Deep Time. " The new hall aimed to put the museum’s fossils in context by highlighting how Earth’s climate has changed over the past half-a-billion years.
Sixty million years ago, the planet’s climate was warmer than it is today—from the equator to the poles. Dense, wet forests covered North America all the way to Alaska. Many types of warm-climate plants, including palms, grew in places too cold for them now. This fossil palm leaf (Sabalites sp.), discovered in Petersburg Borough, Alaska, is on display in “The David H. Koch Hall of Fossils—Deep Time” at the Smithsonian’s National Museum of Natural History.
Note: University of Alaska Museum Earth Sciences Collection 35034.