By Brian Switek | Aeon | July 19, 2016 When I hike up into the hills around Salt Lake City, above the Bonneville Shoreline Trail where the sagebrush gives way to the shade of the forest, mastodons are on my mind. Immense bones pulled from a sinkhole on the nearby Wasatch Plateau placed Mammut americanum in the area about … Continue reading Extinction is forever: de-extinction can’t save what we had