Human evolution theory utilizing concepts of neoteny & female sexual selection
An etiology of neuropsychological disorders such as autism and dyslexia, and the origin of left handedness.
The notion that mans first language was primarily gestural, carried on with hand and arm signals rather than vocal sounds, has been supported by a distinguished line of scholars: Condillar (1746), Tylor (1868, 1871), Morgan (1877:35n), Wallace (1881, 1895), Romanes (1988), Wundt (1912), Paget (1944, 1963), and Johannesson (1949, 1950). The gestural theory seems to be the most attractive of the many glottogonic hypotheses advanced so far, and receives support from recent studies of chimpanzees and other primates, such as Gardner and Gardner (1969, 1971), Premack (1970a,b, 1971), and Menzel (1971), as well as from other sources. The fact that this evidence was unavailable to earlier proponents of the gestural theory explains some of the weaknesses in its former formulations. (Hewes GW (1973) Primate communication and the gestural origins of language. Current Anthropology 14: 5)
Recent hunting peoples present dances consisting of remarkably accurate imitations of the movements of animals, and animal mimicry is also employed in narration of hunting exploits. Animal dances are a staple of ethnographic dance literature, and some Upper Paleolithic paintings seem to represent such mimicry. If such animal mimicry, not necessarily in the form of standardized dances, goes farther back in the past, it would have provided a kind of feedback from the motor habits of other species which would have formed a gestural or mimed domain of animal names, a kind of motor onomatopoeia. If, as some early prehistoric sites indicate, osteodontokeratic remnants from hunting or scavenging were available to the early hominids, these could have served as props or costume elements for animal reenactments, in which vocal imitation would have added verisimiltude, provided the neural mechanisms for its production were sufficiently evolved. (Hewes GW (1973) Primate communication and the gestural origins of language. Current Anthropology 14: 8)
The Gardners and Fouts noted that Washoe learned signs which involved touching parts of her own body faster than signs traced in the air, possibly because of the tactile reinforcement from the skin touched. ... The peculiarly human association of right-handedness and left-hemisphere dominance for both language skills and precise manual manipulations could well be the outcome of a long selective pressure for the clear separation of the precision grip from the power grip, combined with manual-gesture language exhibiting a similar (and related) asymmetry. ... The manual-gesture language model for glottogenesis has the virtue of following the line of least biological resistance, in that it demands no changes -- at least for a very long period -- in neural of buccolaryngeal anatomy or function, other than in the direction of greater precision of control. Other glottogonic theories are vulnerable on this point, since the movement from a language-less hominid to a speaking one is much more difficult to understand than the movement from a gesture language, with cerebral lateralization already in being, to a vocal transformation. Jakobson (1964, 1967) has observed that noises, apart from speech sounds, still have a low communicative value, a fact first clearly realized in the era of radio drama with sound effects. .... Fortunately, we may turn to the mouth-gesture hypothesis, first elaborated by Paget (1963 and many previous publications) and Johannesson (1950, also with numerous earlier publications) and first suggested by Wallace (1881, 1895), for a way in which vocal sounds could have come to be systematically linked with elements of a manual-gesture language. These authors believed that lips, mouth, and tongue roughly imitate hand and sometimes other body-part movements, particularly when the latter are engaged in communicative or manipulative activity. This notion is unlike the bow-wow or onomatopoeic theory in that the sounds produced by mouth gesture and accompanying vocalization do not bear any acoustic resemblance to the manual signs or their external referents (if acoustic similarity were even possible). With the interjectional of yo-he-ho theory it shares only the idea that vocalization may accompany strong emotion or physical exertion. Because of their articulate character, sounds produced in mouth gesture would not closely resemble normal primate calls. Some could be clicks, which are audible without outflow of air from the lungs, and which some linguists claim are archaic (Stopa 1968). (Hewes GW (1973) Primate communication and the gestural origins of language. Current Anthropology 14: 9-10)