Taste was evolution’s first sense, a way for bacteria to touch one molecule to another to decide in a binary way if something was food or poison. Taste was the scaffolding for the development of smell, which gave life chemical information from distant places. Sensitivity to vibrations developed into touch and hearing, to give fragile organisms more information about the world beyond their own membranes, and rudimentary understandings of direction and distance. Electromagnetic sensitivity, from infrared to ultraviolet to variants of electrical and magnetic sensitivity, gave organisms senses to
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