The Proto-Human language (also Proto-Sapiens, Proto-World) is the hypothetical direct genetic predecessor of all the world's spoken languages. It would not be ancestral to sign languages. The concept is speculative and not amenable to analysis in historical linguistics. It presupposes a monogenetic origin of language, i.e. the derivation of all natural languages from a single origin, presumably at some point of the Middle Paleolithic. As the predecessor of all extant languages spoken by modern humans (Homo sapiens), it would not necessarily be ancestral to a hypothetical Neanderthal language.