Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-06-02T22:29:36Z No. of bitstreams: 1 FlaviaMolLanna_DISSERT.pdf: 2377354 bytes, checksum: 0fe56f07a87578273cda933a22b3a564 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-06-08T22:58:23Z (GMT) No. of bitstreams: 1 FlaviaMolLanna_DISSERT.pdf: 2377354 bytes, checksum: 0fe56f07a87578273cda933a22b3a564 (MD5) / Made available in DSpace on 2017-06-08T22:58:23Z (GMT). No. of bitstreams: 1 FlaviaMolLanna_DISSERT.pdf: 2377354 bytes, checksum: 0fe56f07a87578273cda933a22b3a564 (MD5) Previous issue date: 2017-02-21 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico (CNPq) / Quais os processos e mecanismos respons?veis pela diversifica??o das esp?cies? Essa ? uma quest?o antiga que tem sido revolucionada com o avan?o tecnol?gico, computacional e metodol?gico, e tem sido agora compreendida de uma forma que antes n?o era poss?vel. A filogeografia ? uma multidisciplina que utiliza ferramentas derivadas da biogeografia, filogenia molecular e gen?tica de popula??es para entender o contexto da distribui??o dos genes no tempo e espa?o. O presente estudo utiliza an?lises filogen?ticas e filogeogr?ficas para inferir os processos determinantes na diversifica??o de lagartos do g?nero Lygodactylus nas Florestas Tropicais Sazonalmente Secas (FTSS) da Am?rica do Sul. No primeiro cap?tulo n?s investigamos as rela??es entre os Lygodactylus Sul Americanos, buscando entender a influ?ncia do Arco Pleistoc?nico em sua diversifica??o e se essas esp?cies representam um grupo monofil?tico. Atrav?s de an?lises filogen?ticas e de delimita??o de esp?cie, n?s recuperamos o monofiletismo do grupo quando comparado com as esp?cies Africanas e reconhecemos L. klugei como um complexo de esp?cies cr?pticas. N?s sugerimos o aumento de duas para cinco esp?cies de Lygodactylus na Am?rica do Sul. O tempo de diverg?ncia entre L. klugei e as esp?cies candidatas end?micas das FTSSs n?o foi congruente com a hip?tese do Arco Pleistoc?nico. Por?m, a fragmenta??o das FTSS pode ter influenciado na diverg?ncia de L. wetzeli e uma esp?cie candidata end?mica de um enclave de FTSS no Cerrado (S?o Domingos, regi?o do Vale do Paran?). No segundo cap?tulo investigamos a diversifica??o dentro da Caatinga, testando o papel do rio S?o Francisco (RSF) como barreira geogr?fica nesse bioma. Utilizamos um lagarto end?mico dessa regi?o (L. klugei) como modelo de estudo. N?s delimitamos as poss?veis linhagens, investigamos as rela??es filogen?ticas entre elas, a hist?ria de difus?o espa?otemporal e, para testar a hip?tese do rio (barreira para fluxo g?nico), n?s utilizamos uma an?lise de migra??o. N?s recuperamos duas linhagens estruturadas de acordo com o RSF: uma ao norte e outra ao sul do rio. A diverg?ncia dessas linhagens ocorreu ? 295 mil anos atr?s, congruente com a mudan?a do curso do RSF para seu atual curso. N?o encontramos influ?ncia do paleocurso do RSF na estrutura??o de L. klugei. / Which processes and mechanisms are responsible for species diversification? This old question has been revolutionized with technological, computational and methodological advancements, and is now being understood in a way that was previously not possible. Phylogeography is a multidiscipline that uses tools derived from biogeography, molecular phylogeny, and population genetics to understand the context of gene distribution in time and space. The present study uses phylogenetic and phylogeographic analyses to infer determinant processes in the diversification of the lizard genus Lygodactylus in Seasonally Dry Tropical Forests (SDTF) in South America. In the first chapter we investigate the relationships among South American Lygodactylus species, seeking to understand the influence of the Pleistocenic Arc on its diversification and whether these species represent a monophyletic group. Through phylogenetics and species delimitation analyses we recovered the monophyly of the group in relation to African species and recognized L. klugei as a cryptic species complex. We suggest that Lygodactylus in South America actually comprises five species instead of two. The divergence time among L. klugei and candidate species endemic to SDTFs was not congruent with the Pleistocenic Arc Hypothesis. However, we suggest that the fragmentation of SDTFs likely influenced the divergence of L. wetzeli, and of a candidate species endemic to a SDTF enclave within the Cerrado biome (S?o Domingos, Vale do Paran? region). In the second chapter we investigate the diversification within the Caatinga, testing the role of the S?o Francisco River (SFR) as a prominent geographic barrier. We used a lizard endemic to this region (L. klugei) as study model. We delimited the existent lineages, investigated the genetic relationships between them, the spatio-temporal diffusion history, and used a migration analysis to test the riverine hypothesis (barrier to gene flow). We recovered two lineages structured in respect to the SFR: a northern and a southern one. Lineage divergence occurred 295 kya, congruent with the course change of the SFR to its current position. We found no influence of the paleo-SFR on L. klugei structure.