Robert Walker has led another team of scholars applying the phylogenetic method to cultural and linguistic data. This time the paper entitled “Cultural Phylogenetics of the Tupi Language Family in Lowland South America” (free access) is about the reconstruction of the ancestor states for a set of 11 cultural variables for proto-Tupi (paternity beliefs, dances, sibling terminologies, post-marital residence, etc.), mapping it on the internal classification of the Tupi language family and circumscribing the likely geographical homeland for Tupi-speakers. Rob and I corresponded about this project back in 2006. Pursuant to those exchanges, Walker et al. used my database of kinship terminologies to code Tupi sibling terminologies for this paper (trait no. 5 in the table below). To simplify the coding they broke the Tupi sibling sets into two groups – complexly organized sets (type G) that lexicalize the semantic features of relatives age, relative sex and Ego-Sex and the simple sets without those distinctions. Walker et al.’s type G encompasses a wider variety of sibling set types than Murdock’s type G and my types G-5, G-6, G-8, but overall this rough division gives Walker et al. a good handle on understanding the dynamics of change in Tupi sibling terminologies. Notably, their conclusions are consistent with the evolutionary trend toward the simplification of sibling sets that I identified in the global sample. Now in addition to the well-documented sibling nomenclature simplification in Austronesian languages (see “The Genius of Kinship” for details and references), we have the case of Tupi languages displaying the same trend. It’s noteworthy, however, that in some cases Tupi languages show a more dramatic simplification of sibling sets, with languages such as Siriono going all the way from type G to type A (anóNge Sib) within the time afforded by the differentiation of the Tupi language family, but for the most part they maintain complexly differentiated sibling sets. At the same time Austronesian sibling terminologies show a less dramatic simplification from type 10 (the daughter type of G-8 and G-6) to type 1 but type 1 is very frequently found among them.
Walker et al. put the simplification trend in a concrete historical perspective pertaining to the evolution of Tupi social organization as a whole:
“Our phylogenetic reconstructions suggest that Proto-Tupi was likely characterized by a higher level of cultural complexity than seen in many contemporary Tupi societies and similar in many ways to the more complex Tupi societies (e.g., Munduruku and Tupinamba). Given correlations among several of the cultural traits examined here, it seems likely that some cultural traits are commonly lost together in culture-loss processes that reduce complexity in multiple social domains. The most extreme examples are for nomadic Tupi-Guarani hunter-gatherers that lived in small bands (Guaja, Siriono/Yuqui, Xeta, Ache). Trait reconstructions over the linguistic phylogeny indicate that these societies lost a number of cultural traits including canoes, shamans, ‘‘G’’ sibling terminology, and corporate structure, in addition to losing horticulture and sedentarism, in at least 4 independent events toward reduced cultural complexity.”
Walker et al. leave Juruna sibling terminology uncoded (? in their table on the left) but we do have information on Juruna sibling terms (uuraha o\\Sib, uidza y\\Sib, uadidja wB, uaibi mZ), which would make it fall into Walker et al.’s type G. Technically speaking, it’s type 10, according to the nomenclature adopted in The Genius of Kinship, which is derived from the most complex type G. It’s very rare in the New World but is typical for Austronesian-speakers and Papuans (likely an independent development from type G in both areas).
The divergent position of Karitiana in the Tupi linguistic tree (see below) caught my attention because of the complex nature of Karitiana kinship terminology outside of the sibling set. As described by Rachel Landin (Kinship and Naming among the Karitiana of Northwestern Brazil. M.A. thesis. University of Texas at Arlington, 1989), Karitiana kinship terminology is Bifurcate Collateral with Relative Age and Relative Sex distinctions in the parent generation. These distinctions are not typically found in Amazonia and the Relative Age distinctions in combination with Bifurcate Collateral segregation of same-sex and opposite-sex siblings of parents is more reminiscent of North American Indian terminologies (e.g., Uto-Aztecan, South Athabascan) than of South American ones. Intricate forms of name inheritance further complicate the kinship classification. It would be ideal to be able to compare Karitiana with Tupinamba and Munduruku to determine exactly the kind of social complexity is reconstructible for proto-Tupi. But overall the thesis of the simplification of Amazonian societies is consistent with the theory advanced by Paul Henley (South Indian Models in the Amazonian Lowlands. Manchester, 1996).
Finally, Walker et al. assume a genetic connection between Tupi and Carib languages (a linguistic proposal by Aryon Rodriguez that has received support from population genetics). Sibling terminologies seem to be consistent with this grouping as both Tupi and Carib languages are rich in examples of complexly differentiated sibling sets, all the way to Murdock’s and my type G. A few sibling terms in Tupi and Carib dialects are related, according to Rodriguez (see on the left, from Rodriguez 1985, p. 381, with Bk Bakairi, Gl Galibi, Tb Tupinamba, Tp Taulipang, Tr Tupari, Wn Wayana). If the same logic of simplification applies to the Tupi-Carib protolinguistic community, type G is reconstructible for this proto-language as well. Walker et al. may be able to prove or disprove this hypothesis applying the method of cultural phylogenetics.