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In 2013, starfish — including the morning sun star, the richly hued och re star and the sunflower star, whose limbs can span four feet across — started dying by the millions along the Pacific Coast from Mexico to Alaska.

They were succumbing to a wasting disease. It began with white lesions on their limbs, the dissolution of the surrounding flesh, a loss of limbs and finally death. Understanding, let alone solving, the problem would take research.

One day, shortly after the epidemic began, Drew Harvell, a professor of ecology and evolutionary biology at Cornell University who had been sounding the alarm about the disease, received a curious letter.

“I received a $400 check in the mail from a group of schoolchildren from Arkansas,” Dr. Harvell said. “These kids were so upset about the idea of starfish disappearing from the oceans that they went out and they did this fund-raiser and raised 400 bucks for us to help in our research. I never asked them to do this. They just did it.”