Mary Treat’s Venus Flytrap Experiment


Mary Treat (b. 1830 — d. 1923) helped tarantulas build their homes, tamed angry wasps, and much more all from her modest New Jersey home. She wrote hundreds of articles, a book, and regularly consulted and corresponded with Charles Darwin.

She was drawn to the stranger things. The insects and arachnids that most people think are dangerous or disgusting. But it was a plant that made Mary lose her nerve of steel. Not just any plant, but a carnivorous one. Mary had been determined to understand how these plants work, how they trap and digest their prey. She watched contentedly as dozens of ants were lured to drink the sweet liquid on the edge of the pitcher plant, only to disappear to their deaths over the pitcher’s edge. She let her home fill with flies, and observed as the sundews wrapped themselves around their victims, and the butterworts digested them with their sticky fluid.

But it was perhaps the most famous of the carnivorous plants that caused Mary to flinch: the Venus flytrap. In a moment of desperate curiosity, Mary put her finger inside a Venus flytrap to see what would happen. It clamped around her finger. And Mary waited. At first she felt nothing. On she waited, sitting quietly for hours with her finger inside the trap. Finally she felt a strange tingling in her finger, and before long the sensation grew stronger and traveled all the way up her arm. Mary withdrew, unsure of what further pain, discomfort, or damage the plant would inflict, but knowing firsthand the bite of the Venus flytrap was indeed real.

Art by Sarah Pedry. Words by Sarah Pedry and David Obuchowski.