Signal

"One last question: did you know that gastropods have poor eyesight? Even worse, apparently they don’t really look at anything. They navigate in other ways. Despite their two eyes at the tips of their fully extended tentacles, they can barely see at all; at most, they can distinguish the intensity of light and operate mainly 'by smell' ''.
Daniel Arasse, On n'y voit rien, Gallimard, Paris, 2003

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