KU Student Scientist Uncovers Ancient Link Between Plants and Fungi in Antarctica
University of Kansas student Andrew Schwendemann recently traveled to the most-frigid ends of the Earth to locate Antarctic rocks offering a glimpse back millions of years into the evolution of plants and fungi. His derring-do work there just landed him lead authorship of an article in the renowned journal Proceedings of the National Academy of Sciences.
“It’s a big ordeal,” Schwendemann said. “We flew to Christchurch, New Zealand, to get outfitted with cold-weather gear. From there, we take a C-17 and land on a glacier on the edge of Antarctica. Then we had to go through survival school at the main U.S. base at McMurdo. Next, we flew out to our base camp, which was halfway between the coast and the South Pole. Every morning, helicopters would fly us out to the sites where we wanted to collect, and they’d pick us up at the end of the day.”
Dropped in the Antarctic wilderness, Schwendemann and his colleagues hunted for primeval rocks, called silicified peat, known to contain fossilized conifers and other plants. Each day, the team loaded burlap bags with hundreds of pounds of them, and eventually hauled their find back to the KU campus in Lawrence.
“We get these big rocks of silicified peat back into our lab, and then we use a diamond-bladed slaw to slash through them like a loaf of bread,” said Schwendemann. “Then, we dip it in hydrofluoric acid that destroys the minerals, but not the plant parts. So we’ll have these 240-million-year-old plant walls, and they’ll stick up in relief. Then we put acetone on the rock surface itself, and apply a plastic sheet. The acetone dissolves the plastic at first. After a while, the acetone evaporates and the plastic sheet hardens again.”
When peeled away, the plastic sheet clearly reveals the ancient conifer cell walls, ready to be examined under powerful microscopes.
From examining the conifer root fossils, Schwendemann discovered a more ancient connection between specialized plant root structures — called nodules — and fungi than had been known previously. The KU researcher described a mutually beneficial relationship whereby a fungus lives safely in a conifer’s root and extends into the soil, bringing the tree nutrients it wouldn’t get otherwise.
Indeed, the conifer may have evolved to grow the root nodules specifically to help fungi.