Doutorado em Ecologia e Evolução (ICB)
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Navegando Doutorado em Ecologia e Evolução (ICB) por Por Orientador "Collevatti, Rosane Garcia"
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Item Efeito da estrutura da paisagem na diversidade genética neutra e adaptativa de Caryocar brasiliense Camb. (Caryocaraceae)(Universidade Federal de Goiás, 2018-10-26) Amaral, Tatiana Souza do; Ribeiro, Milton Cezar; http://lattes.cnpq.br/4158685235743119; Collevatti, Rosane Garcia; http://lattes.cnpq.br/9979596352166630; Collevatti, Rosane Garcia; Soares, Thannya Nascimento; Marco Júnior, Paulo De; Lima, Natacia Evangelista de; Chaves, Lázaro JoséUnderstanding how the human-caused impacts and environmental heterogeneity caused by these changes affect genetic variability is essential for the preservation and planning of animal and plant species management. The main objective of this work was to investigate the effects of landscape changes on diversity and on the adaptive and neutral genetic differentiation of Caryocar brasiliense Camb. (Caryocaraceae), an endemic species and tree symbol of Cerrrado. To do so, we selected five landscapes in regions near Goiânia, in the state of Goiás. Within each landscape, we selected two sample sites. To measure the structure of the landscape, we calculated metrics related to the amount of habitat, connectivity and heterogeneity in buffers of 2km, 4km and 6km that delimited the landscapes and in buffers of 500m around the sampling sites. In each site, we collect fruits of, on average, 10 mother-trees. The seeds of these fruits were measured (longitudinal diameter, transverse diameter and mass) and planted in a greenhouse. Afterwards, we performed character measurements of that were known to be important for the early stages of the plant, such as: percentage and germination time, initial and final heights, height growth rate, initial and final diameters, growth rate of diameter, number of leaves, leaf length and width, fresh and dry mass of root and shoot, root and shoot length. The experiment carried out in the greenhouse allowed us to access the quantitative genetic variability and the evolutionary potential of C. brasiliense in the sampled sites. Thus, in the first chapter, we evaluated the evolutionary potential of C. brasiliense in each sampled site and the effects of landscape structure on quantitative genetic variability. In the second chapter, we analyzed the effects of landscape structure on the diversity and genetic differentiation of adults and juveniles of C. brasiliense and verified if there is a time-lag of the effects of habitat change on the loss of genetic diversity in these landscapes. For this, in the same sites where we sampled the fruits, we collected leaves of adults and juveniles for DNA extraction. From the genotypes obtained using nine microsatellite loci, we access the neutral genetic diversity of C. brasiliense and relate it with the landscape metrics and the population effective size. From these analyzes, we found that functional connectivity was an important variable to explain the patterns observed in the quantitative genetic variability of most of the characters studied, such as those related to seeds, seedling diameter and leaf characters. The amount of habitat (%) was the variable that determined the patterns of genetic-quantitative differentiation for the growth rates of height and diameter, as well as being important to explain the neutral genetic diversity of juveniles. Intermediate levels of the amount of habitat had the highest values of allelic richness and heterozygosity expected for juveniles, while loss of genetic diversity, measured as the difference between adult and juvenile genetic diversity, was influenced by functional connectivity. The reduction of the genetic diversity detected mainly in juveniles evidences a time-lag effect, and corroborates with studies that affirm that species of long life, as C. brasiliense, require a long period of fragmentation so that the changes in heterozigosity are detected. In general, the movement of the pollinators and dispersers, and consequently the gene flow, is an important process in the maintenance of the evolutionary potential and genetic diversity of this species since functional connectivity was the most important variable influencing the neutral and adaptive genetic diversity of C. brasiliense. In this way, our results demonstrate that restoring or conserving habitat areas in key places that allow the connectivity of the landscape are essential for the conservation of this species.Item Padrões e processos na diversificação de Tropidurus oreadicus (Squamata, Tropiduridae): um lagarto de áreas abertas do cerrado e ilhas savânicas na Amazônia(Universidade Federal de Goiás, 2014-07-28) Mello, Rodrigo de; Colli, Guarino Rinaldi; http://lattes.cnpq.br/2272000258230548; Collevatti, Rosane Garcia; http://lattes.cnpq.br/9979596352166630; Collevatti , Rosane Garcia; Bastos, Rogério Pereira; Miranda, Núbia Esther de Oliveira; Vaz-Silva, Willian; Giugliano, Lilian GimenesHistorical biogeography is currently invigorated due to the molecular genetics revolution in systematics and population genetics, besides the new approaches to test biogeographical hypothesis. Furthermore, new tools for generating ecological niche and palaeoclimate models are shifting the direction of phylogeographic studies by making them more integrated. The Brazilian savanna (Cerrado biome) vegetation covers some 2 million km² of Central Brazil, representing about 23% of the land surface of the country. Although recent studies indicate that the biome harbours a rich, complex and characteristic reptilian fauna, patterns of species distribution and genetic structure remain poorly understood for the Cerrado herpetofauna. The lizard Tropidurus oreadicus has an interesting ecological history related to the open vegetation formations, occuring in open areas of Cerrado and in savanna enclaves in Amazonia rainforest. In order to investigate its evolutionary history, we used a robust geographical and genetic sampling, a multilocus dataset and palaeodistribution modelling based on the projection of current distribution into past environments (6 and 21ky BP) using 11 methods for SDMs and five coupled atmosphere–ocean global circulation models (AOGCMs). Our results provide new insights on the genetic and spatial structure of the species revealing six major mtDNA lineages and divergence dates with both deep (Tertiary) and shallow (Quaternary) patterns of diversification for the species tree. The spatial analysis for paleodistribution modelling showed little retractions in Mid-Holocene and the refugia map suggests a broad stable area for the species. The relative influences of Neogene geomorphological events and Quaternary climatic changes as causal mechanisms on the species diversification are discussed. Lastly, we present some inferences about potential future changes in the species geographical distribution, aiming to contribute with the recent conservation discussions on how to preserve Brazilian biodiversity in public policies of conservationItem Padrões e processos associados à diversidade da anurofauna em áreas abertas da América do Sul: filogeografia de physalaemus cuvieri (anura: leptodactylidae)(Universidade Federal de Goiás, 2014-03-21) Miranda, Núbia Esther de Oliveira; Maciel, Natan Medeiros; http://lattes.cnpq.br/2116561844584292; Collevatti, Rosane Garcia; http://lattes.cnpq.br/9979596352166630; Collevatti, Rosane Garcia; Werneck, Fernanda de Pinho; Amaro, Renata Cecilia; Silva, Daniela de Melo e; Bastos, Rogério PereiraPhylogeographic studies are revealing complex evolutionary histories in the South American diagonal of open formations. The phylogeographic patterns of South American biota are better documented for forest-dwelling species but remain insufficient in respect to open vegetation habitats. The frog Physalaemus cuvieri presents wide distribution being a typical species of open areas. It represents an ideal model to investigate hypotheses about the role of events of Tertiary versus Quaternary in the genetic diversity and diversification of the anurofauna of the Neotropical open areas. Here we used a range-wide sampling of P. cuvieri and DNA regions with different mutation rates to investigate historical and spatial process that promoted the species diversification. We integrated the phylogeographic approach with ecological niche models to understand how Miocene/Pliocene orogenic events and/or Pleistocene climatic oscillations have contributed to shape the current diversity and distribution of the species population. We sampled 609 individuals from 76 populations. Three mitochondrial fragments (12S, 16S and cytochrome b) and one nuclear (rhodopsin) were sequenced for all individuals. We identified 248 haplotypes in mitochondrial region and six haplotypes in nuclear region. It is possible to recognize three haplogroups, widely distributed in the network, which assemble sympatric and geographically close populations haplotypes. There is a clear separation between the haplotypes that shows a ‘diagonal break’ of the populations of P. cuvieri with their connnection occurring in the northeast through the haplotypes of São Luiz - MA population. The hierarchical AMOVA showed significant differentiation among populations of the different river basins (FCT = 0.273). The divergence between the lineages of P. cuvieri and outgroups occurred during the Miocene, around 16.13 Ma [SD 10.43 to 20.43]. Divergences between the major groups and subgroups occurred during the Miocene (between 16 and 5.7 Ma). Divergences in the Pleistocene occurred mainly within populations, or among geographically close populations. The analysis of spatial diffusion estimated the most recent dates for the dispersal events of the lineages of P. cuvieri. Much of their diversification remained registered in the Tertiary, although we can not neglect the influence of Quaternary climatic fluctuations. Lineages of P. cuvieri seems to have an origin at central Brazil, with three main routes of colonization: one towards the south, one to the north and other to the northwest. The potential distribution of P. cuvieri appears did not change drastically across the last glacial cycle. Our results revealed a complex history diversification of P. cuvieri, with Tertiary orogenic events playing prominent role in the early diversification, by also favored by the climatic fluctuations of the Quaternary. This process contributed to the diversification of younger lineages and also structured populations. Therefore, P. cuvieri shows a pattern of deep divergences with strong regional structuring of populations, despite its widespread distribution and generalized ecology. Because of that deep and structured divergence, Physalaemus cuvieri populations also should be treated as a species complexItem Estrutura filogenética de assembleias de árvores do Cerrado. Compreendendo a biogeografia e história evolutiva do bioma(Universidade Federal de Goiás, 2016-03-04) Souza Neto, Advaldo Carlos de; Cianciaruso, Marcus Vinicius; http://lattes.cnpq.br/3421612628316830; Collevatti, Rosane Garcia; http://lattes.cnpq.br/9979596352166630; Collevatti, Rosane Garcia; Cianciaruso, Marcos Vinicius; Teles, Aristônio Magalhães; Duarte, Leandro da Silva; Carlucci, Marcos BergmannUnderstanding the processes that guide species distribution is a classic aim of Ecology. Several approaches were used to reach this objective. The use of phylogenetic data to elucidate and comprehend ecological patterns and processes has grown recently. However, the use of phylogeny as proxy to species traits, considering the premise that species phylogenetically closely related are functionally related, has been contested along the years. From these questions, several authors have thought about what is the best way to use the phylogenetic knowledge to better understand ecological and biogeographical patterns and processes. The Cerrado is the second largest biome of Brazil and has great biodiversity and many endemic species. The knowledge about the biome evolution has grown, but more studies still are necessary do deeply understand the origin of its biodiversity. Our aim was to use phylogenetic knowledge to try clarifying the evolutionary history of Cerrado biome. The first chapter brings a scientometric analysis of “Phylogenies and community ecology” paper by Webb et al. (2002). We conclude that the paper was very important to establish the “Ecophylogenetics” field, because even with a contested initial view, the work was important to bring the researchers attention about the use of phylogenies in ecological and evolutionary studies. The second chapter brings a phylogenetic approach to understand the Cerrado biome evolution and its relationship with other biomes surrounding it, using the Caesalpinioideae subfamily (Fabaceae) as model. In this chapter we observed that Cerrado biodiversity was originated by habitat shifting, which species from another biome, Caatinga in this case, can colonize a new environment and establish. However, some clades evolved in situ, diversifying in the Cerrado biome. The third chapter bring a deeper study on Cerrado evolution, using as model all trees that occur on Cerrado biome. In this chapter we studied the phylogenetic relationships among species that occur in different phytophisiognomies. We conclude that, although cerrado sensu stricto and cerradão be very similar, the other phytophysiognomies have independent evolutionary histories. Lastly, we conclude that phylogenetic knowledge is useful to understand historical and biogeographical processes. The vegetal biodiversity diversification of Cerrado was influenced by historical events like the C4 plants diversification and the uplift of Brazil Central shield. Besides, there are evidences that the Cerrado phytofisiognomies have independent evolutionary histories. The chapters add up previous studies to favour a better comprehension of Cerrado origin and evolution of its biodiversity, bringing new perspectives for future studies.