Diferencias entre la comunicación animal y el lenguaje humano
The differences between animal and human communication are profound, but all the differences seem to derive from a single basic fact: humans possess a natural, inborn facility to be creative with symbols; as far as we know, animals do not.
Comunicación animal
Animal systems are set responses to stimuli. Animal communication is used to express something more or less immediately present in space and time. The signs of animal communication are used as indexes. Animals can't communicate about yesterday.
El lenguaje humano
Human language can be used as an index, just like animal communication, but it may also exhibit what has been termed displacement. Humans can not only talk about things that are absent but also about things that have never been.
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