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| Author(s): |
Fernanda von Hertwig Mascarenhas Fontes
Total Authors: 1
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| Document type: | Doctoral Thesis |
| Press: | Campinas, SP. |
| Institution: | Universidade Estadual de Campinas (UNICAMP). Instituto de Biologia |
| Defense date: | 2016-09-22 |
| Examining board members: |
Vera Nisaka Solferini;
Marcos Roberto Dias Batista;
Ana Maria Lima de Azeredo Espin;
Evandro Marsola de Moraes;
Fábio Sarubbi Raposo do Amaral
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| Advisor: | Vera Nisaka Solferini |
| Abstract | |
The great biodiversity and complex geological history of South America offers a number of issues to be addressed with the use of phylogeography. The aim of this study was to test hypotheses about the biological diversity in the Neotropical region, contributing to understand the consequences of the establishment of an open vegetation area in the central region of the continent separating its two large rainforest, the Amazon and the Atlantic. In order to get distinct perspectives about this scenario we studied phylogeographical patterns of two Aglaoctenus spiders (Araneae, Lycosidae): A. lagotis, distributed in a variety of phytophysiognomies, and A. castaneus, restricted to the wet forests, both limited to the Neotropical region of South America. We estimated genetic diversity and structure, built haplotype networks, made bayesian phylogenetic inferences and demographic analyses. Results were summarized in two manuscripts that correspond to the two chapters in this thesis. In the first chapter, entitled "Insights on the Neotropical history provided by a multilocus phylogeographic study of the web spider Aglaoctenus lagotis (Araneae, Lycosidae)", we analyzed 26 populations distributed from eastern Amazon to southern Atlantic Forest and gathered three nuclear (ITS2, H3 and TIF5A) and one mitochondrial (COI) markers. A. lagotis diversification started on Pliocene, but genetic structure strongly increased on Pleistocene, suggesting that climate oscillations from this period may have contributed to this pattern. Results also suggest distinct colonization events of tropical and subtropical portions of Atlantic Forest. In chapter two, "Phylogeographical patterns of Aglaoctenus castaneus (Araneae, Lycosidae) between Amazon and Atlantic Forest", we used six populations and two molecular markers (COI and ITS2). The high genetic structure between the two biomes suggests a vicariant role for the dry diagonal; however, the estimated divergence between clades correspondent to each rainforest was posterior to the emergence of this savanna region, indicating gene flow maintenance between populations within each forest until Quaternary. Lineages from each biome also presented genetic structure, suggesting that historical events in a regional scale also contributed to shape the current diversity pattern of this species. Our results agree with the general consensus that Neotropical biomes history is complex, mainly due to orogenic and climatic changes that influenced the landscape over time, and highlight the importance of using different organisms with a broader distribution to elucidate biogeographical questions in the Neotropics (AU) | |
| FAPESP's process: | 11/17244-4 - Phylogeographic analysis of the species of the genus Aglaoctenus (Araneae, Lycosidae) |
| Grantee: | Fernanda von Hertwig Mascarenhas Fontes |
| Support Opportunities: | Scholarships in Brazil - Doctorate |