In 1972, two of these shadowy felines crept into Helen Freeman’s life. And from the moment she saw them, Freeman, then a zoo volunteer, was captivated. “They changed my life,” she wrote in her memoir, “Life, Laughter and the Pursuit of Snow Leopards,” describing the cats curled up in the back of their enclosure. A student of animal behavior at the UW, Freeman began to spend hours quietly observing the creatures, starting with just an arm visible around a corner, slowly easing more into view as they grew used to her. By the mid-1970s, Freeman’s fascination with the snow leopards at the zoo had deepened into focused research.