Perception and the evolution of sound systems

This paper explores the impact speech perception may have had on the phylogeny of the sound systems of natural human languages and the capacity of human beings for them. The theoretical frame work is perception-based phonology (PBP). The problem is viewed from three major perspectives, namely:
- The typological perspective: Why are sound systems structured the way they are, in particular, with respect to the universal set of sound contrasts utilized for distinctive purposes in the languages of the world, i.e. the distinctive features?
- The learnability perspective: Which abilities do neonates have to have to be able to learn the sound system of the language(s) they happen to be born into?
- The animal perspective: Are there any parallels between the abilities of the human neonate and non-human species?

It is claimed that perception is primary and that articulation/production is secondary. It is argued that the typology of distinctive features as the basic units of sound systems are based on certain properties of the auditory system of neonates. As for ontogeny, these auditory properties allow neonates/infants to develop/learn the phonological categories of whatever language(s) they happen to be confronted with. Since the perceptual categories of the respective target language(s) are in place before infants produce their first words it is assumed that these perceptual categories control the development of production. It is further assumed that properties of the auditory system that give rise to the distinctive features are neither language-specific nor species-specific because they are shared by other species, such as chinchillas, macaques, Japanese quail, or starlings.

Three major conclusions are proposed:
- In evolutionary terms, these auditory properties must be very old, much older, in fact, than the evolution of the anatomical peculiarities of the vocal tract as a prerequisite for the production of - human - speech.
- The auditory properties that determine the distinctive features did not develop as the result of any adaption because of exposure to speech but they constitute the prerequisites, i.e. the fore-runners on the basis of which sound systems evolved.
- The auditory properties under scrutiny here are not restricted to phonological systems, i.e. they are not language-specific.

mimeo, English Department, Kiel University, 1998.