Reply to comment

Eve, you ask, "What about, as you suggest, talking? In an environment with no talking, would a human instinctually try to speak (can we ever know?)?"

Several experiments or instances of torture have occurred in various cultures and eras that have attempted to accomplish just what you ask: isolation from human language in attempt to discover if speech is innate, or in attempt to discover a pure, unadulterated, divine language.

A few examples (though literary) might interest you:
-In Herodotus' Histories, the pharaoh Psamtik attempts to discover which ethnic group "came first" by isolating two infants from speech and seeing what language they spoke. Psamtik's logic was such that whatever word was spoken must belong to the language of the "first culture." Since the first word uttered was the Phrygian translation of "bread," the Phrygians were ruled the first culture.
-Frederick II tried a similar experiment "but the children died before they ever spoke any words" (Paul Auster, City of Glass).
-Paul Auster's novella "City of Glass" portrays a character whose father isolated him from language and human contact in order to find God's language and to return to the pre-lapsarian connection between language and meaning/function. (READ THIS NOVELLA!)