On a moonless night, light levels can by more than 100m times dimmer than in bright daylight. Yet while we are nearly blind and quite helpless in the dark, cats are out stalking prey, and moths are flying agilely between flowers on our balconies.
While we sleep, millions of other animals rely on their visual systems to survive. The same is true of animals who inhabit the eternal darkness of the deep sea. In fact, the overwhelming majority of the world’s animals are primarily active in dim light. How is their formidable visual performance possible, especially in insects, with tiny eyes and brains less than the size of a grain of rice? What optical and neural strategies have they evolved to allow them to see so well in dim light?
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