Ancient poppy seeds and willow wood offer clues to the Greenland ice sheet’s last meltdown and a glimpse into a warmer future

Under a microscope, a tiny elongate poppy seed, small tan spikemoss megaspores and black soil fungus spheres found in soil recovered from under 2 miles of Greenland's ice. Halley Mastro/University of Vermont, CC BY-ND

As we focused our microscope on the soil sample for the first time, bits of organic material came into view: a tiny poppy seed, the compound eye of an insect, broken willow twigs and spikemoss spores. Dark-colored spheres produced by soil fungi dominated our view.

These were unmistakably the remains of an arctic tundra ecosystem – and proof that Greenland’s entire ice sheet disappeared more recently than people realize.