From Spiders to Languages: a Phylogenetic Journey
- Chousou-Polydouri, Natalia
- Advisor(s): Gillespie, Rosemary G.
Abstract
The parallels between biological and linguistic evolution have been recognized for a long time. In this work, contemporary phylogenetic methods are applied to address empirical questions in both fields. Additionally, the parallel histories and methodologies between biological systematics and historical linguistics are reviewed and novel approaches for coding linguistic data for contemporary phylogenetic methods are suggested.
Biogeography of Orsolobidae The biogeography of the spider family Orsolobidae was used as a case study to test the ‘drowned’ New Zealand hypothesis and to assess the importance of the breakup of Gondwana in its diversification. A molecular phylogeny of Orsolobidae and numerous outgroups was dated using both fossil node and substitution rate calibrations. The resulting divergence age estimates are consistent with the Gondwana breakup, while they reject the ‘drowned’ New Zealand hypothesis.
Linguistic characters and phylogenetics The history and methods of biological systematics and historical linguistics are briefly reviewed while underlining their similarities and differences. Novel coding methods are proposed for lexical, phonological and morphological linguistic characters and how they can be analyzed with computational phylogenetic methods.
Classification of Tupí-Guaraní A new internal classification is suggested for the Tupí-Guaraní language family based on lexical data analyzed with Bayesian phylogenetic methods. The dataset is coded using a novel cognate presence-absence method which includes items that have undergone semantic shift. The results largely agree with the lower subgroups of previous classifications, but suggest a significantly different higher structure of the family, with Kamaiurá sister to all other languages. Our results also suggest a Tupí-Guaraní homeland between the Xingu and Tocantins rivers and new hypotheses for the spread of the family in South America.