Fossil specimen of Prototaxites taiti on a mossy surface, resembling the landscape of the Early Devonian. Credit: Laura Cooper, University of Edinburgh. Prototaxites are something of a prehistoric mystery. They were the first giant organisms on land, towering over ancient landscapes at heights of up to 8 meters. They had smooth trunk-like pillars and no branches, leaves or flowers. And unlike trees, they had no true root system. Instead, they may have been