Total number: 19 Accretion (residual) zones: southwestern Ethiopia, Southern Africa, Nuba Mountains Technological innovations leading to Spread zones: Bantu, Nilotic, Surmic, Eastern and Southern Cushitic Pastoralism in the case of Nilotic and Surmic Blench (2006) on West Africa: The Bellwood-Renfrew model is problematic when applied to Africa in general, because no terms unambiguously related to agriculture have been successfully reconstructed in the protolanguage of any of the African language phyla.
Climatological changes The expansion of the Niger-Congo family presumably is related to both climatological and technological changes (Blench (2006) Linguistic isolates like Banga me, Dompo, Jalaa, Laal, and Mpra, but also larger units like Songai and Mande most likely constitute remnants of an earlier diversity that must have characterized West Africa, as well as other parts of the continent.
Northeastern Africa: The spreading of Nilo-Saharan
Accretion (residual) zones: – Southwestern Ethiopia – Southern Africa – Nuba Mountains (Sudan) Nettle (1999:150): – The ethnolinguistic map is a product of people’s social behaviour. But the same social behaviour is motivated by the economic necessities of subsistence. The latter in turn are linked to the ecological setting.
Language and social identity: Three types of language contact phenomena causing (further) genetic differentiation Shift-induced interference and structural borrowing from Bantu into Luo (Nilotic): Development of noun classes: Singularplural ja-luojo-luo‘Luo person/people’ a-guok i-guok-i‘puppy’ Development of tense marking on verbs: na-a-lUwOrEc ‘I was catching fish earlier on’ nya-a-lUwOrEc ‘I was catching fish yesterday’ nyoc-a-lUwOrEc ‘I was catching fish the day before yesterday’ yand-a-lUwOrEc ‘I caught fish a few days ago’ Result: Luo deviates considerably from closely related Lwoo languages.
Metatypy in Baale (Surmic) Didinga-MurleBaaleTirma-ChaiMe’en Didinga-MurleBaaleTirma-Chai Phonologywords ending in consonants only vowel-final words vowel-final words Lexiconheavy borrowing from Tirma-Chai little borrowing from Baale Lexical idioms Ota UtU ‘nipple (lit. breast- mouth)’ way tugo 'nipple (lit. breast-mouth)’. Constituent orderV-initial SVO, VSO, OVS, SOV SVO, VSO, OVS, SOV Result: Baale deviates considerably from the closely related Didinga-Murle languages.
Esoterogeny in Tima (Katla; early Niger-Congo descendant) Lexically close to Katla plus Julud, but grammatically rather deviant: – Relatively free constituent order in Tima (SVO, OVS, VSO, SOV etc. strongly governed by pragmatic principles) versus SVO structure in Katla. – Ergativity (no evidence for ergativity in Katla-Julud) – Verb morphology strongly governed by constituent order Oral tradition among the Tima and neighbouring groups: “Tima is extremely difficult to learn.” Probably not a case of esoterogeny (in spite of the oral tradition), but rather of shift-induced interference. Result: Tima deviates considerably from the closely related Katla-Julud group Oral tradition of deliberate language change probably a post hoc rationalisation, in order to explain why their language is so different.
Emblematic role of language for ethnic identity Nettle (1999:59): Where individuals have large and dispersed social networks, one may expect linguistic uniformity; where social networks are small and tightly self-contained, many distinct languages will ultimately evolve. Compare Hill (2001) on “localist” strategies of closed agricultural language communities in Central America. Some conclusions: – Higher degree of genetic diversity than assumed by Joseph Greenberg – Spread zones absorbing languages of earlier inhabitants. Therefore, probably even more genetic diversity in the past – Accretion zones – Climatological factors – Technological factors – Social attitudes towards language