What was the first time that we know that non-human animals have color vision? From what I can find, the first person who scientifically came to that conclusion was John Lubbock in 1888. What was so strange about it was that he studied Daphnia - a plankton (!). He discovered that the plankton was attracted to yellow light, but not to white light. Lubbock also reasoned that insects must have color vision, but was not able to scientifically demonstrate it.
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