A two million-year-old trunk from a larch tree is stuck in the permafrost within the coastal deposits at Kap Kobenhavn, Greenland. The tree was carried to the sea by the rivers that eroded the former forested landscape. Scientists have analyzed 2-million-year-old DNA extracted from dirt samples in the area, revealing an ancient ecosystem unlike anything seen on Earth today, including traces of mastodons and horseshoe crabs roaming the Arctic. (Svend Funder via AP)