Muran
Muran notes
No relevant phenomena have been identified in this language family. Its most well known member is Pirahã, which has figured large in recent discussions of complexity, embedding and Universal Grammar. However, though it has rich inflectional morphology, notable in the verb, we have not found evidence of non-trivial allomorphy or gross form-function mismatches. The main source is the sketch grammar from the Handbook of Amazonian Languages (Everett 1986). This more recent quotation confirms the judgement: 'Although the complexity of the verb is very high, with perhaps more than 16 suffix classes, there is nothing about its semantic composition, stress, or morphological attachment that requires recourse to the notion of embedding to account for Pirahã morphology. The system, however complex, can be accounted for by a "position class" analysis along the lines of Everett (1986), in which individual morphemes occupy linearly arranged, semantically distinguished slots.' (Everett 2005: 631)
References
Everett, Daniel L. 1986. Pirahã. In: Desmond C. Derbyshire and Geoffrey K. Pullum (eds) Handbook of Amazonian languages, vol. 1, pp. 200--326. Berlin: Mouton de Gruyter.
Everett, Daniel L. 2005. Cultural Constraints on Grammar and Cognition in Pirahã: Another Look at the Design Features of Human Language. Current Anthropology 46(4), 621-634.
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