Development of human language
No one yet agrees on when language was first used by humans (or their ancestors). Estimates range from about two million (2,000,000) years ago, during the time of Homo habilis, to as recently as forty thousand (40,000) years ago, during the time of Cro-Magnon man. We know that, at least once during human evolution, a system of verbal communication emerged from proto-linguistic or non-linguistic means of communication, but beyond that little can be said.
Several linguistic theories
Bow-wow theorie: This hypothesis places the origin of human language in onomatopoeia: the various imitative sounds that humans make to mimic the sounds of the world around them. It claims that humans formed their first words by imitating animal sounds.
Pooh-pooh theorie: According to this hypothesis, the first words developed from sighs of pleasure, moans of pain, and other semi-involuntary cries or exclamations. These vocalisms then became the names of the phenomena that made people say them.
Ta-ta theorie: Charles Darwin lent his authority to this hypothesis. According to this, human language represents the use of oral gestures that began in imitation of hand gestures that were already in use for communication.
Yo-he-ho theorie: According to this hypothesis, language arose in rhythmic chants and vocalisms uttered by people engaged in communal labour.
Premises for language
Control of respiration: The dimension of nerve channels in certain medulla bones could give information about the ability to control respiration. But up to now there could no explicit increase of this nerve channels be found.
Flexibility of the tongue musculature: This musculature is controlled by the twelfth cranial nerve. It pulls through a channel in the posterior lower cranial bone. The dimension of this channel could give some information about the muscle control but there is no explicit difference between fossil craniums and ours.
Position of the larynx: The larynx by most of the mammals is positioned high in the cervix, opposite of the first three cervical vertebras but by an adult human it is positioned on a level with the fourth to seventh cervical vertebras. The benefit: humans can produce more than 100 different sounds specially vocals. The con: unlike to other mammals humans can not breath and swallow food at the same time.
Subcranial line: If the subcrainal line is flat the larynx is positioned up in the cervix, if it is arced the larynx is positioned lower. The subcrinal line of australopiticus is flat and similar to apes. Since Homo erectus (300.000 to 400.000 years ago) it becomes more and more arced.
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