Acquiring a Visually Motivated
Language: Evidence From
It is clear that signed languages are richly structured linguistic systems, with grammatical structures that resemble those found in spoken languages (see Emmorey, 2002; Klima & Bellugi, 1979; Stokoe, Casterline, & Croneberg, 1965). However, an interesting fact about sign languages is that they appear to be more similar typologically speaking than we see with spoken languages. For example, most, if not all, sign languages have rich morphological systems that share remarkable linguistic similarity with each other, but not with spoken languages, such as the morphological systems of verb agreement and classifiers (Schembri, 2003; T. Supalla & Webb, 1995; see also Slobin, chapter 2 this volume).
Some of these morphological systems have a strong underlying iconic motivation in that aspects of grammatical structure bear some relationship to objects and locations that occur in the real world. Many of the early studies on American Sign Language (ASL) remarked on this rich iconic potential, in comparison with spoken languages, such as Klima and Bellugi (1979), who noted that "mimetic representation is the source of many symbols used in signing" (p. 11; see also DeMatteo, 1977; Mandel, 1977; Taub, 2001). The concept that signed languages have some kind of iconic motivation is probably older than any discussion on their status as a linguistic system (see Baynton, 1996). This is not to say that signed languages are only iconic representations of the real world. There are a large number of arbitrary signs, with little connection to the referents (e.g., in ASL, MOTHER, APPLE, NAME). Sign languages are not restricted to iconic representation.