Intelligent Design

Written by Joseph Caputo ’07
Photography by Andrew Lichtenstein ’88 & Linda Kohn '73

It’s easy for a scientist to think of a question that needs answering. Designing the experiment that answers the question isn’t so simple. But a creative scientist can transmute complexity into elegance, turn limitations—of time, technology, money, and knowledge—into strengths, and satisfy her inquiry, all with one well-designed experiment.

Experimental design is the heart of scientific investigation; when it’s done right, it can be close to an art form. Linda Kohn ’73, a mycologist, and Carol Shoshkes Reiss MS ’73, a neuroimmunologist, show us how it’s done.

The Magic of Mushrooms

In the summer of 1985, Linda Kohn ’73 was picking gnat-sized mushrooms 225 miles above the magnetic North Pole. Armed with a hand lens, pocketknife, tweezers, little boxes, and lunch, she spent her days in a lowland arctic oasis bounded by ice-covered cliffs. This stark landscape might seem an unlikely spot for mushrooms to thrive, but there were about 100 visible species, Kohn says.

There are projected to be 1.5 million species of fungus in the world, thriving in environments as diverse as the nutrient-rich rainforest and the frozen tundra. Kohn, one of the world’s few experts on cup fungi and professor of biology at the University of Toronto, has traveled to many of these far-flung locales over the past 30 years, collecting fungi, considering their life histories, and pondering their evolutionary success. But exactly how, she wondered, did this diversity of species come to be? This became the defining question of Kohn’s career when, 20 years after her northern expedition, she and her co-workers designed the first experiment to show adaptation in action, demonstrating its role in the evolution of new species.