Sightless cells hidden within the eye may set our circadian rhythms, trigger migraines, and explain the seasonal ebb and flow of our moods

摘要

There was no way the blind mice could see, yet somehow, they could. The year was 1923, and a Harvard grad student named Clyde Keeler had set out to compare eyes from different animals, starting with mice that he bred in his dorm room. Keeler cut open one mouse's eye and put it under a microscope. Immediately he realized something was wrong. Missing from the eye was the layer of rods and cones, the photoreceptors that catch light. Turning back to his colony, Keeler realized that half of his animals were blind. Somehow a mutation had arisen, wiping out their rods and cones.