Typological differences in phonology are observed in marked features and phonological hierarchies (Greenberg, 1969).
Marked features refer to the additional articulatory features that are more complex in nature and less preferred in sound sequences.
Phonological hierarchies refer to the preference order of phonology in single phonemes and phonemic clustering across various positions in a word.
For instance, according to Greenberg (1969), nasal vowels require an “additional resonance chamber, the nasal, besides the oral chamber which functions alone in the oral vowels” (Greenberg, 1969, p.476). Nasal vowels are considered to be a marked feature in languages that have both nasal and oral vowels. Similarly, nasal vowels are less preferred over oral vowels because of their restricted acoustic environments, where they can occur in selected word formations. Thus, nasal vowels are placed on a lower position than oral vowels within the phonological hierarchy.
Consonant Clusters
According to sonority sequencing universals (where sonority is loudness of a speech sound), language users would generally prefer consonant sequences (C1C2, where C denotes consonant) with high sonority difference over those with low sonority difference between the sequences.
blif > bnif > bdif > lbif
In particular, Berent, Lennertz, Jun, Moreno, Smolensky (2008) had done a research study on word-initial consonant cluster preference. The guiding principle of the study is that speakers, when presented with perceived mispronounced words, tend to repair them within their perception to be correctly pronounced. For example, speakers of languages with word-initial consonant clusters (i.e. English speakers and the word ‘black’) would be able to perceive blif as monosyllabic while words beginning with lbif would be misperceived as lebif, changing the syllable count to disyllabic.
In the study, they recruited native Korean speakers. Due to their lack in consonant clusters in the beginning of words in their language, it presented a clear contrast with English speakers who are regularly exposed to word-initial consonant clusters. The study posited that if Korean speakers demonstrated similar preference order and syllabic-count judgement as English speakers, their perception of initial consonant clusters would be attributed to reasons beyond exposure to certain speech sounds.
They found that Korean speakers did show preference for consonant sequences in an order that is similar to their English speaking counterparts. Hence this was in support of the hypothesis of the study: “adult human brain possess knowledge of universal properties of linguistic structures absent from their language” (Berent, et al, 2008, p.5324). This instinct could be attributed to the human brain’s capacity in universal linguistic knowledge, advocating for human’s innate ability to produce language.
Sign Languages
In Evans and Levinson (2009), they talked about physical characteristics of vocal tract being “the clearest evidence for biological basis for language” (p.433). At the same time, they also brought up another form in which human natural language are realised: natural sign languages.
Sign languages are gestural rather than verbal, and it is created in by people, for people, who are unable to acquire verbal languages, such as Hearing Impaired.
Perhaps, in using sign languages to disprove phonological universals would seem inadequate – after all, signed languages have no need of speech sounds. However, Evans & Levinson (2009) did emphasized that the existence of sign languages account for the “modality-plastic nature of our language capacity” (p. 433). This implies that human brains, to a certain extent, are adapted to be able to create new communication systems where the existing system is not longer suitable for their usage. This further emphasize for the notion of languages are adapted in relation to our cognitive capabilities.
Therefore, the conflicting evidences as illustrated above had drawn an indistinct picture of how phonological universals in languages are supported in Linguistics and served to show how capricious languages are.