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| Author(s): |
Jair Francisco Mendes Junior
Total Authors: 1
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| Document type: | Master's Dissertation |
| Press: | Campinas, SP. |
| Institution: | Universidade Estadual de Campinas (UNICAMP). Instituto de Biologia |
| Defense date: | 2015-08-26 |
| Examining board members: |
Vera Nisaka Solferini;
Luciana Bolsoni Lourenço;
Fernando de Faria Franco
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| Advisor: | Vera Nisaka Solferini |
| Abstract | |
South America is the most biodiverse region of our planet, presenting two important forest formations, the Amazon and the Atlantic Forest. Several studies indicate that these two rainforests were continuous in the past and started to separate at the end of Miocene with the formation of the "dry diagonal". The influence of this event in the patterns of species distribution has been widely investigated using phylogeographic analysis. In this study, the phylogeographic patterns of Argiope argentata (Araneae: Araneidae), a species widely distributed in the Neotropical region, were investigated to evaluate the influence of the formation of "dry diagonal" in the diversification of this species¿ lineages. Samples of A. argentata were collected and the mitochondrial region COI of 185 individuals from 33 locations was sequenced. The genetic diversity and genetic structure indices were calculated, a haplotype network and a phylogenetic tree were inferred and the occurrence of demographic events was investigated. A.argentata presented low nucleotide diversity and a high haplotype diversity. Four genetic groups were observed, presenting genetic structure not associated with geographic distribution. The diversification of the lineages of this species happened during the Pleistocene. Demographic analyzes indicate recent demographic expansion, around 100,000 years ago, with subsequent stability around 20,000 years ago. Our results suggest that the formation of "dry diagonal" did not influence the current distribution of A. argentata lineages and that the Quaternary climatic oscillations influenced the process of diversification of this species¿ lineages (AU) | |
| FAPESP's process: | 13/05812-3 - Phylogeography of Argiope argentata (Araneae: Araneidae) |
| Grantee: | Jair Francisco Mendes Júnior |
| Support Opportunities: | Scholarships in Brazil - Master |