BDTD - Biblioteca Digital de Teses e Dissertações
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Master Thesis O etnoconhecimento e a conservação de sementes crioulas no estado do Rio Grande do Norte: (re)existências e ancestralidades(Universidade Federal do Rio Grande do Norte, 2025-07-24) Teixeira, Elida Cassandra de Souza; Souza, Cimone Rozendo de; https://orcid.org/0000-0002-4903-0839; http://lattes.cnpq.br/8227598190372706; http://lattes.cnpq.br/0814684035446870; Silva, Andréa Leme da; https://orcid.org/0000-0001-9944-3052; http://lattes.cnpq.br/1437384786936034; Silva, Ana Tereza Reis da; https://orcid.org/0000-0001-8204-0732; http://lattes.cnpq.br/1290786927670370The appreciation of traditional knowledge has been highlighted in the literature as a strategic path to promoting sustainability. In this context, conservation practices for Creole seeds stand out, considered essential for the social reproduction of traditional populations and for environmental conservation. This study aims to investigate the traditional knowledge involved in the conservation of Creole seeds in seven Citizenship Territories of Rio Grande do Norte. To this end, the first part consisted of a systematic review of the literature on Creole seeds, aiming to identify the predominant elements in academic literature on the topic. Subsequently, the results of field research conducted as part of the project "In Search of Seeds that Color the Semiarid Region: Identification, Characterization, and Mapping of Creole Seeds in the Citizenship Territories of Rio Grande do Norte" (In Search of Seeds that Color the Semiarid Region: Identification, Characterization, and Mapping of Creole Seeds in the Citizenship Territories of Rio Grande do Norte) were presented. This project, developed by the Rural Studies Laboratory of UFRN, aims to analyze the conservation and management practices of Creole seeds adopted by family farmers in Rio Grande do Norte. The literature review showed that Creole seeds are more than genetic resources: they are a cultural and political heritage that expresses the identity, memory, and resistance of traditional peoples and communities. The empirical results revealed the richness of local knowledge about the management, conservation, and symbolic meaning of seeds, understood as "seeds of life," linked to ancestry and spirituality. Practices such as markets, community banks, and networks of guardians emerge as forms of collective resistance and safeguarding agrobiodiversity. The research also highlighted the leading role of women and community organizations in maintaining this knowledge, as well as the challenges faced, such as the rural exodus and the lack of continuous, adequate, and agroecologically based public policies, fundamental not only for biodiversity but also for building a truly sustainable, fair, and pluralistic development model. However, a growing effort was observed to involve rural youth in training and collective seed management spaces. In conclusion, Creole seeds represent ancestral technologies and symbols of resistance and autonomy, demanding recognition of their biocultural values and the development of public policies that strengthen traditional territories. Thus, it is argued that defending Creole seeds is defending life, diversity, and the possibility of futures rooted in the knowledge and practices of communities that cultivate not only food, but also stories, dreams, and sustainable ways of life.Master Thesis Ação do extrato hidroalcoólico de Spondias tuberosa Arruda na nefropatia diabética induzida por estreptozotocina em ratos(Universidade Federal do Rio Grande do Norte, 2025-09-05) Sena, Vitória Natália Ferreira de; Medeiros, Karina Carla de Paula; Ladd, Fernando Vagner Lobo; https://orcid.org/0000-0002-6670-8656; http://lattes.cnpq.br/0907170560632356; http://lattes.cnpq.br/3379499427344725; http://lattes.cnpq.br/0625151106063093; http://lattes.cnpq.br/0625151106063093; Martins, Fabiane Ferreira; http://lattes.cnpq.br/6569473943631639; Vieira, Giciane Carvalho; https://orcid.org/0000-0003-4577-8943; http://lattes.cnpq.br/6625645865394113; Santos, Pedro Paulo de Andrade; https://orcid.org/0000-0002-5793-3886; http://lattes.cnpq.br/2878739335493429Diabetic nephropathy (DN) is the second leading complication of diabetes mellitus and one of the most concerning for global public health. Currently, pharmacological therapy for DM and nephropathy has significant limitations due to the high number of side effects and ineffectiveness. Therefore, alternative and complementary treatments based on medicinal plants hold potential promise for DM. The species Spondias tuberosa Arruda, popularly known as umbuzeiro, has been widely used in traditional medicine for the treatment of DM, but has been little explored scientifically. Therefore, the objective of this study is to evaluate the effect of the hydroalcoholic extract of the fruit peel of Spondias tuberosa Arruda (ExSt) on DN based on biochemical, morphological, and stereological analyses in streptozotocin (STZ)-induced diabetic rats. Forty-four male Wistar rats (CEUA: 319.056/2022) were divided into groups CG: normoglycemic animals; DM: hyperglycemic animals; EX: normoglycemic animals treated with ExSt; DMEX: hyperglycemic animals treated with ExSt; and DMIN: hyperglycemic animals treated with insulin. ExSt (500 mg/kg, p.o.) was administered daily for 30 days after the onset of DM, as well as insulin (10 U). Blood and renal tissue samples were collected for analysis. The observed results demonstrate the toxicity of DM to the kidney, since the diabetic group had decreased weight and increased glucose and urea levels. Histopathological findings, markers of general structural damage, and glomerular NO and CASP-3 concentrations were similar. Treatment with ExSt failed to significantly reverse clinical and biochemical parameters, but demonstrated improvement in established DN, as histopathological findings, cortical volume, glomerular volume, mean glomerular volume, GBM thickening, fibrosis, and markers of oxidative stress and tissue damage were minimized. Although further research is needed to more fully validate the action of ExSt in experimental DN, it is noteworthy that it has a potential antioxidant and renal protective effect against DM. Furthermore, this work contributed to a better understanding of the pathophysiology of DM and encouraged the search for new treatment approaches using natural compounds available in Brazil's rich and diverse flora.Master Thesis Análise de variantes patogênicas em AGPAT2 e avaliação bioquímico-molecular de indivíduos com lipodistrofia generalizada congênita dos tipos 1 e 2(Universidade Federal do Rio Grande do Norte, 2024-03-28) Melo, Maria Eduarda Cardoso de; Campos, Julliane Tamara Araújo de Melo; https://orcid.org/0000-0002-8501-5521; http://lattes.cnpq.br/3504274193684794; http://lattes.cnpq.br/6286758647430147; Ferreira, Leonardo Capistrano; Cortez, Virginia Oliveira FernandesCongenital Generalized Lipodystrophy (CGL) is a rare disease that causes the loss of adipose tissue (AT) throughout the body from birth. Patients with CLL have low levels of leptin and adiponectin (APN), important adipokines produced by AT. There are four types of CGL, with types 1 and 2 being responsible for more than 80% of the cases described in the literature and with patients already reported in northeastern Brazil. The molecular etiology for LGC 1 and LGC 2 is the presence of pathogenic variants (PVs) in the AGPAT2 and BSCL2 genes, respectively. This study carried out the molecular analysis of the main VPs described for AGPAT2 (c.366-588del, c.589-2A>G, c.646A>T, c.570C>A, c.369-372delGCTC, c.202C>T, c.514G>A, c.144C>A) and an analysis of the effects on their transmembrane and functional domains. The genotype vs. phenotype relationship of the first patients described in the literature for the PVs in question demonstrates the relationship between molecular alterations and the clinic, so that patients with PVs that more significantly affect the proteins show a greater number of clinical symptoms. In addition, we carried out the molecular diagnosis of two sisters with VPs in compound heterozygosity for c.299G>A and c.493-1G>C and a new patient described for the c.366-588del variant. Using next-generation sequencing (NGS), a panel of genes associated with adipose tissue-related diseases was analyzed in LGC patients, which showed the presence of different VPs for the BSCL2 gene. The comparative study of leptin and APN dosages between the LGC 1 and LGC 2 groups showed that LGC type 2 patients had lower leptin concentrations, while no differences were observed between APN dosages in these two groups. At the level of expression of enzymes involved in repairing oxidized DNA damage (APE-1, OGG1 and PPARG), no significant differences were observed between the LGC 1 and LGC 2 groups, although both types had higher levels of expression of these genes when compared to that observed in control individuals. This suggests that the different molecular etiology of the two types of LGC is not, in itself, a significant parameter for altering redox homeostasis between these two groups. Further studies are needed to better understand the relationship between LGC and oxidative stress, DNA repair and cellular response.Master Thesis Novas espécies de Collembola (Arthropoda, Hexapoda) de áreas de transição Caatinga Cerrado no Piauí, Brasil(Universidade Federal do Rio Grande do Norte, 2025-02-20) Rodrigues, Iandra Vitória Bezerra; Bellini, Bruno Cavalcante; Nunes, Rudy Camilo; https://orcid.org/0000-0002-4838-1151; http://lattes.cnpq.br/4334165724196513; Molin, Anamaria Dal; Cipola, Nikolas GioiaSpringtails are essential arthropods in the soil's edaphic fauna, widely distributed across the planet. Ranging in size from 0.12 to 17 mm, they feed mainly on fungi, bacteria and decaying plant material, playing a vital role in soil enrichment and nutrient cycling, crucial factors for the sustainability of terrestrial ecosystems. The state of Piauí stands out for being home to an extensive area of transition between two important Brazilian biomes: Cerrado and Caatinga. This region is characterized by a diverse mosaic of vegetation types, forming an ecotone rich in biodiversity and endemism. Currently, there are about 9,600 species of springtails described worldwide, of which only 507 are known from Brazil. Although interest in taxonomic studies of springtails has grown in the country in recent decades, the state of Piauí still has scarce and punctual research. This study presents the description of three new species of Collembola from the state of Piauí with a bibliographic review of their respective genera. The specimens were previously collected between 2019 and 2023 using pitfall traps and entomological aspirators in two areas of Piauí, Palmares National Forest and Urubu-Rei Waterfall. For identification and taxonomic description, the specimens were analyzed under an optical microscope with phase contrast following specific bibliography, drawn and vectorized for the preparation of anatomical plates. The type material of the three new species is deposited at the Collembola Collection of the Federal University of Rio Grande do Norte and at the Invertebrate Collection of the National Institute for Amazonian Research. Our results include the description of three new species: one of Mastigoceras, a genus endemic to Brazil, being the second species described to the genus after a hundred years from the first description. In this study we also provided morphological and systematic updates to the genus; the description of the fourth species of Adisianus, a genus which until now had only been recorded from northern Brazil and Mexico; and finally, the description of the second species of Lepidosira from the Neotropical Region. We hope that some of this data will be useful for the administrations of the Conservation Units from where the material was collected.Doctoral Thesis Ação antioxidante e efeito neuroprotetor de polissacarídeos sulfatados(Universidade Federal do Rio Grande do Norte, 2024-12-04) Lucena, Alessandra Marinho Miranda; Câmara, Rafael Barros Gomes da; Rocha, Hugo Alexandre de Oliveira; https://orcid.org/0000-0003-2252-1221; http://lattes.cnpq.br/4651814546820796; https://orcid.org/0000-0001-5109-1991; http://lattes.cnpq.br/9200036511632745; https://orcid.org/0000-0002-1698-5428; http://lattes.cnpq.br/5486564758103808; Scortecci, Katia Castanho; Guzen, Fausto Pierdona; Santos, Pablo de Castro; Ferreira, Éder GalinariNeurodegenerative diseases are the result of multifactorial biological mechanisms, involving both exogenous and endogenous causes. Due to the increase in life expectancy and the predicted growth of dementia conditions, there is a growing concern in seeking more effective prevention and treatment for neurodegeneration. Oxidative stress has been shown to be an important factor in the development and progression of these diseases, due to intrinsic characteristics of nervous tissue, such as low regenerative capacity and high energy demand. Marine algae are sources of various bioactive molecules, especially sulfated polysaccharides (SP). These compounds are important for the survival of algae and have significant biological activities, such as antioxidant and anti-inflammatory properties. These properties can be useful in the treatment of neurodegenerative diseases. The SP from algae have shown promise as an alternative for neuroprotection. Nine species of algae were identified whose SPs exhibit antioxidant action under different conditions. Forty-four fractions rich in sulfated polysaccharides (FRP) were obtained. These FRP were evaluated for their cytotoxicity in Neuro-2A cells at different concentrations (0.1, 0.25, 0.5, and 1 mg/mL). From each FRP, two concentrations were selected, one higher and one lower, which showed MTT reduction values equal to or greater than 80%, for analysis of protection against oxidative damage induced by hydrogen peroxide. To select the FRP that would be evaluated for possible protective mechanisms employed, the results of yield parameters, cytotoxic effect, and neuroprotective potential in cell culture were considered to construct a Score. The possible mechanisms involved were analyzed through the determination of hydrogen peroxide scavenging potential and the effect on the expression of genes in the antioxidant pathway (Keap1, Nfr2, Sod1, Cat, Gpx, Hmox1, Gclc, Gclm) and the subunits of the transcription factor NFκB (Nfkb1 and Rela). Additionally, the antioxidant protection capacity was evaluated in an in vivo model (zebrafish). Of the 44 FRP evaluated, 42 did not show cytotoxic effects against Neuro-2A cells at at least one of the evaluated concentrations. All evaluated algae had FRP that protected Neuro-2A cells from oxidative damage induced by hydrogen peroxide. Furthermore, through the Score, it was possible to observe that brown algae had the best results. Based on these data, four FRP (DJ 1.2, SF 0.5, SS 1.3, and DM 1.0) were selected for the evaluation of the possible mechanisms involved. The data obtained demonstrate that the mechanisms used by these samples range from direct action on oxidant molecules to the modulation of endogenous antioxidant mechanisms, promoting an increase in the expression of genes related to the translation of antioxidant enzymes and a reduction in the expression of genes related to a pro-inflammatory and pro-oxidant response. Additionally, these polysaccharides were able to promote protection against oxidative stress in an in vivo model. These data are important for the development of future evaluations of these molecules, as they provide knowledge about their potential neuroprotective effect, possible mechanisms, and antioxidant activity in more complex organisms.Master Thesis Frugivoria em Myrteae (Myrtaceae) nas Américas(Universidade Federal do Rio Grande do Norte, 2024-07-31) Moreira, Victor de Paiva; Staggemeier, Vanessa Graziele; https://orcid.org/0000-0003-4911-9574; http://lattes.cnpq.br/4357034543526737; https://orcid.org/0000-0002-9837-8380; http://lattes.cnpq.br/4501919971368014; Pinto, Miriam Plaza; Gressler, ElianaMyrtaceae is one of the most species-rich families among angiosperms and plays a crucial ecological role in tropical regions, particularly in the Americas, where it is represented by the tribe Myrteae. This group exhibits a wide diversity of fleshy fruits that serve as resources for fauna, relying on frugivores for seed dispersal. This plant-animal interaction impacts the evolutionary success of both lineages, and it is expected that fruit selection by frugivores may explain the high species diversity within this tribe. Based on this premise, we divided this dissertation into two chapters. The first chapter aimed to review the consumption of Neotropical Myrteae fruits by animals through a systematic literature search using the Web of Science, Scopus, and SciELO databases, as well as additional references cited in these studies. We found 324 sources of information. The research covered 18 countries from Mexico to southern South America, with a high concentration of studies in Brazil (188 out of 324; 58%). We recorded a total of 1,858 frugivory interactions, involving 200 Myrteae species and 292 frugivore species (152 bird species, 106 mammals, 17 fishes, 8 ants, 8 reptiles, and 1 crustacean). Of this total, 722 interactions were unique records between identified species (i.e., excluding duplicate records found in different studies and records where one or both species were unidentified at the species level). Approximately 40% of the studies recorded interactions involving Myrteae species with some level of taxonomic uncertainty (species or genus). The interactions occurred with at least 19 genera of Myrteae, with Eugenia being the most studied, appearing in 165 studies (51% of the total). This genus also had the most studied species, at least 65, and the most recorded interactions (541 in total, with 371 involving identified animal species). In the second chapter, we filtered the initial database for interactions where both plant and animal taxonomy were known at the species level and focused only on vertebrates (since interactions with ants and crustaceans are exceptions in the dispersal patterns of Myrteae). We then characterized the associations between fruit and seed traits and their frugivores, testing the hypothesis of seed dispersal syndromes and their impact on Myrteae speciation. From 225 studies, we found 1,019 interactions (697 unique) involving 254 vertebrate species and 163 Myrteae species. Primates consumed 79 Myrteae species (127 unique interactions), while birds consumed 42 species (221 unique interactions), with other vertebrates playing a lesser role in the group's dispersal. The majority of Myrteae species produced small, black fruits with a single seed, which were dispersed by all visiting groups, particularly birds. The second most important group of fruits included large, yellow, multi-seeded fruits, characteristic of the genera Psidium and Campomanesia, which were more frequently visited by primates. Other dispersal syndromes were unclear, with significant overlap in fruit and seed traits consumed by birds and mammals. Even when mammals were subdivided by order, dispersal syndromes were not evident in Myrteae. Additionally, we found a sampling bias in frugivory studies, with a high concentration of data from the Paraná domain region. To remove a potential biogeographic effect, network metrics were calculated only for this domain (105 Myrteae species, 139 animal species, 568 interactions, 422 unique interactions). The network exhibited modularity, but without an evident pattern associated with fruit functional traits or the animals consuming them. Few modules displayed notable characteristics, such as the absence of small fruits in module 1, exclusivity of mammals in module 5, and a predominance of birds and small fruits in modules 8 and 9. This lack of clear patterns was likely due to many interactions occurring with low frequency, obscuring the identification of more general patterns. Many important interactions occurred with primates, some of which acted as connector species and module hubs, including endangered species such as Brachyteles arachnoides, Leontopithecus caissara, and L. chrysopygus, highlighting their importance in maintaining natural forest regeneration in this province. In a scenario of high threats, these species would be the first to disappear, affecting the conservation of these environments. We also found a trend, although not significant, that lineages producing large and yellow fruits tend to have lower speciation rates. While lineages producing small, black fruits, consumed by all frugivore groups, exhibit more varied speciation rates, with only these lineages showing higher speciation rates within the Myrteae tribe. The database generated in this dissertation advances our knowledge of frugivory interactions in Myrteae in the Americas, identifies knowledge gaps, and suggests directions for future studies. Moreover, the analysis of the interaction network from a macroevolutionary perspective provided insights into how fruit selection by frugivores may have shaped the evolution and diversification patterns in plants.Master Thesis Diversidade de frutos em Myrtaceae: hipóteses ecológicas e evolutivas para o sucesso desta família neotrópico(Universidade Federal do Rio Grande do Norte, 2024-06-27) Cunha, Hercília Freitas da; Staggemeier, Vanessa Graziele; Vasconcelos, Thais Nogales da Costa; https://orcid.org/0000-0003-4911-9574; http://lattes.cnpq.br/4357034543526737; https://orcid.org/0000-0002-1152-5799; http://lattes.cnpq.br/3439479756280087; Vieira Filho, Edson Aparecido; Paterno, Gustavo Brant de CarvalhoFleshy fruits are the link between fauna and flora. They serve as a resource for fauna, while at the same time favouring the colonisation of plant species. Selective pressures in plant-animal interactions can shape fruit and seed characters and have the potential to explain current species diversity. In this dissertation, I used Myrtaceae, one of the most species-rich families in the tropics, as a model to test the effect of plant and fruit characters on the family's speciation rates. Thus, in chapter one I expanded the morphological database of Myrtaceae fruits and seeds, resulting in data for 956 species and adding new variables on display, plant height and life habit. Myrtaceae showed wide morphological variation, with large fruits with several small seeds or small fruits with few small seeds. Black colouring is present in half of the species in the database, occurring in 56.8%, followed by yellow (17.4%) and red (17.4%). Orange, green, brown and grey are less common in the fruits of the Myrteae tribe (8.4%). In chapter two, using the data from chapter one, I tested the relationship between fruit and seed size, seed number, fruit colour and plant height and quantified the influence of these characters on speciation rates in Neotropical Myrtaceae. Only fruit diameter was able to predict speciation rates, i.e. small fruit sizes have high speciation rates. Since fruit diameter is a limiting factor for dispersal, it is expected that this morphology will be selected over time, but contrary to expectations, the other traits are not associated with speciation in the Myrteae tribe, indicating that other abiotic and biotic factors shape current species diversity. In Chapter 3, I tested the visual-attractiveness hypothesis, which predicts that fruits at an intermediate stage of ripeness and with conspicuous colouring increase the attractiveness of the canopy and have an earlier germination capacity. The multicoloured display proved to be more attractive when removed than the unicoloured display, but germination was independent of the type of display of the species, i.e. the seeds were able to germinate at all stages of ripeness. The results found contribute to advancing the understanding of fruit and seed morphological patterns linked to dispersal and their role in the diversity of the Myrtaceae family.Doctoral Thesis Causes and consequences of litter-mixing effects on decomposition in terrestrial and aquatic ecosystems(Universidade Federal do Rio Grande do Norte, 2024-04-30) Alencar, Mery Ingrid Guimarães de; Silva, Adriano Caliman Ferreira da; https://orcid.org/0000-0001-9218-5601; http://lattes.cnpq.br/4147444251852878; http://lattes.cnpq.br/2550864838319536; Tonin, Alan Mosele; Dias, André Tavares Corrêa; Omena, Paula Munhoz de; Ferreira, Verónica Jacinta LopesMost of the organic matter (OM) synthesized in terrestrial ecosystems turns into litter. A set of physiological, ecological, evolutionary, and environmental mechanisms act on both the synthesis and degradation of OM making it very diverse, concerning its chemical and physical traits, which play relevant functional roles in determining the dynamics of litter degradation in ecosystems. The functional litter diversity/heterogeneity has consequences through litter-mixing effects (LMEs) on the decomposition and nutrient cycling in terrestrial and aquatic ecosystems. However, several gaps regarding both the causes and consequences of litter diversity for ecosystem functioning remain poorly understood. Thus, we aimed to assess the causes (Chapters 1 and 2) and consequences (Chapters 3-5) of litter diversity/heterogeneity in decomposition and to understand their effects on the occurrence, direction, and magnitude of LMEs. Chapter I, we tested the generality of flower litter as a labile organic matter and leaf litter as a refractory organic matter in terrestrial ecosystem. Specifically, we evaluated patterns and predictors of flower and leaf litter decomposition at the intra- and inter-specific levels for 29 species. Our results indicate that flower litter had a higher concentration of N, P, and K, while leaf litter had higher density, Ca, Mg, and Na. And that the functional traits, leaching rate, P, Ca, Mg, and Na, predicted the litter decomposition of both litter types. Overall, the differences observed in decomposition rates and functional traits between litter types indicate differences between flowers and leaves in the potential diversity effect on decomposition. In Chapter II, we evaluated the LMEs at the intra-specific level in aquatic and terrestrial ecosystems, using flower and leaf litter of Tabebuia aurea (Silva Manso) Benth. & Hook. f. ex. S. Moore as a model. Our results indicate that the differences in functional litter traits between flowers and leaves resulted in littermixing effects, mostly synergistic effects, associated with complementarity mechanisms. Since flower and leaf litter seem to be a labile and refractory litter, respectively. Our results indicate that the litter diversity at the intra-specific level between different organs could be important in mediating LMEs, and these effects were stronger in terrestrial ecosystems. Our results suggest a feasible secondary role for flowers in after senescence in the OM cycling. In Chapter III, we evaluated how the litter interaction for different temporal dynamics, resulting from different phenological patterns, can affect the LMEs. Specifically, we evaluated how an intermittent or seasonal input of litter affects the occurrence, direction, and magnitude of LMEs in aquatic and terrestrial ecosystems. We did not find clear patterns in the effect of litterfall inputs on decomposition, but we observed a preponderance of LMEs in the aquatic ecosystem, probably related to the different dynamics and nutrient concentrations in its ecosystem due to the experimental conditions. In Chapter IV, through a meta-analysis, we evaluated how the individual response of species in mixtures can alter the occurrence, direction (i.e. positive or negative), and magnitude of LMEs. Differences in functional traits between species and litter identity were the main factors mediating LMEs in both terrestrial and aquatic ecosystems. In Chapter V, also through a meta-analysis, we evaluated the complementarity effects between labile (i.e. higher C: nutrient ratio) and refractory litter (i.e. lower C:nutrient ratio), testing the idea that labile species accelerate the decomposition of refractory species, while refractory species decrease the decomposition of labile species. Our results indicate that labile species showed additive responses when interacting with refractory species; while refractory species had antagonistic responses when interacting with labile species. When evaluating LMEs considering ecosystem type, presence or absence of decomposers, and stage decay, we observed a preponderance of antagonistic effects for labile species. To directly evaluate the responses of labile and refractory litter, we found patterns of LMEs that differed from those expected from previous studies, since labile litter is expected to have an antagonistic response and refractory litter a synergistic response. The results obtained in this thesis contribute to advancing knowledge of LMEs, specifically to evaluate how the causes and consequences of litter heterogeneity may be important in mediating the occurrence, direction, and magnitude of LMEs.Master Thesis Ecologia comparativa e ecomorfologia de espécies de Gymnodactylus (Squamata: Phyllodactylidae) em áreas de Mata Atlântica e Caatinga de região setentrional do nordeste brasileiro(Universidade Federal do Rio Grande do Norte, 2023-11-24) Furtado, Olyana da Silva; Freire, Eliza Maria Xavier; Sales, Raul Fernandes Dantas de; https://orcid.org/0000-0001-9486-6347; http://lattes.cnpq.br/6388455734228621; http://lattes.cnpq.br/4222542127790160; Nunes, Pedro Murilo Sales; Ávila, Robson WaldemarThe genus Gymnodactylus is endemic to Brazil and currently comprises five species, two of which are recorded for the state of Rio Grande do Norte, Gymnodactylus geckoides, predominant in the Caatinga, and Gymnodactylus sp. nov., endemic to the northeastern Atlantic Forest. In some areas of the Brazilian Northeast, such as the dune and restinga ecosystems of the Atlantic Domain in Rio Grande do Norte, these species occur in sympatry, which makes it important to know how they coexist and/or segregate their ecological niches, compared to the use of these niches in areas where only one of these species occurs. In this sense, the feeding ecology and habitat use of G. geckoides and Gymnodactylus sp. nov. were analyzed in two areas of the Atlantic Forest Domain and one of Caatinga. In one of the Atlantic Forest areas (Parque Estadual Dunas do Natal - PEDN), the species occur in sympatry, while in the other, Area de Proteção Ambiental Jenipabu (APAJ), only G. geckoides occurs, similar to the Caatinga area of Estação Ecológica Seridó (ESEC Seridó). As they use different habitats in these areas, the influence of habitats on the morphology of G. geckoides was analyzed. The specimens were captured manually for analysis of stomach contents, and data about the habitat and microhabitat where they were first sighted were recorded. To find out the diet, 105 stomachs were analyzed, 37 from G. geckoides from ESEC Seridó, 23 from G. geckoides from APAJ, 14 from Gymnodactylus sp. nov. and 31 from G. geckoides from PEDN. For analysis of ecomorphological variation, 10 morphometric variables of G. geckoides populations were used. At ESEC Seridó and APAJ, termites (Isoptera) were the most important prey in the diet of G. geckoides. At PEDN, the diet of G. geckoides was mainly composed of Hemiptera, while for Gymnodactylus sp. nov., Isoptera and Formicidae. Regarding electivity, of the 27 categories of prey available at ESEC Seridó, those preferred by the G. geckoides population were Dermaptera, Diplopoda and Isopoda; the other categories were considered rejected. For the APAJ population, out of 20 available prey categories, Blattodea, Coleoptera, Isoptera, Insect Larvae, Pseudoscorpiones and Scorpiones were preferred; Araneae and Hemiptera were slightly preferred and the others were rejected. For the PEDN, among the 20 available categories, the G. geckoides population demonstrated a preference for Hemiptera, Insect Larvae and Lepidoptera, while Gymnodactylus sp. nov. demonstrated to prefer prey such as Coleoptera, Dermaptera, Diptera and Isoptera. A high level of overlap in terms of food niche and total segregation in the spatial niche was found between the two species in sympatry in the PEDN: Gymnodactylus sp. nov. it inhabits areas of high forest and low forest, while G. geckoides was restricted to open areas of beach dunes. The population of G. geckoides in APAJ was recorded in restinga vegetation and in anthropic areas, while in ESEC Seridó, arboreal-shrub vegetation and rocky outcrops were the most used habitats. Due to their restricted occurrence in soilassociated microhabitats, both species were considered terrestrial, but, in sympatry, they segregate in terms of habitat use. Morphological variations were found between populations of G. geckoides from the Caatinga and the Atlantic Forest; for PEDN and APAJ, the morphometric profiles demonstrated similarity. The hind limbs of Atlantic Forest populations are more elongated than those of the Caatinga, demonstrating that the habitat used by the species influences their morphology.Doctoral Thesis Padrões espaciais de biodiversidade e estabilidade da abundância de espécies ao longo de gradientes ambientais(Universidade Federal do Rio Grande do Norte, 2023-06-22) Alves, Wagner de França; Gianuca, Andros Tarouco; http://lattes.cnpq.br/9747367811959611; http://lattes.cnpq.br/7742861573223863; Silva, Adriano Caliman Ferreira da; https://orcid.org/0000-0001-9218-5601; http://lattes.cnpq.br/4147444251852878; Ganade, Gislene Maria da Silva; Teixeira, Duarte de Serpa Pimentel; Bastazini, Vinícius Augusto GalvãoGrowing anthropogenic pressures on earth, particularly those related to urbanizationand agricultural intensification, have resulted in the loss and fragmentation of habitats, with possible consequences for biodiversity and ecosystem stability. However, there is still limited understanding of how different taxonomic groups respond to these pressures andat what spatial scale these effects are strongest. Another uncertainty concerns the level of spatiotemporal change of the different dimensions of biodiversity (e.g., taxonomicand functional). The main goal of this thesis was to evaluate how anthropogenic impactsaffect patterns of diversity and stability of species abundance at multiple spatial scales. For that, we used databases of hundreds of animal metacommunities, collected with high spatial and temporal resolution and through international collaborations from several Europeancountries. This thesis is divided into three chapters. In the first, we investigated howthe relationships between dispersal ability and body size of six groups of arthropods influence therelative amount of β-diversity components: species replacement and nestedness (variationinspecies composition resulting from difference of species richness between communities). For this type of analysis, urban gradients were considered, which were quantified at multiplespatial scales. We found that groups with a positive relationship between body size anddispersal ability showed a more pronounced nestedness pattern towards urban centers comparedto groups that showed a neutral relationship between size and dispersal ability, mainlyat the local scale. This result is in agreement with our hypotheses and indicates that not onlyissize an important attribute that influences species selection along the urban gradient, but that variation in dispersal capacity also influences the organization of urban metacommunities, implying different regional management strategies. In the second chapter, we assessthe prevalence of biotic homogenization and differentiation mainly in Western Europe andrelate these patterns to various functional attributes of butterflies. For this, we usedspecies abundance data collected during a minimum of four and a maximumof twelve yearsand integrated with functional attributes of butterflies in seven European countries. We foundan increase in the proportion of species with greater thermal tolerance and egg volumeinmost metacommunities, regardless of taxonomic and functional homogenization or differentiation scenarios. Finally, in the third chapter, we use the same butterfly data to assess howdifferent facets of diversity and abiotic factors affect the stability of butterflies’ abundance at multiple scales. Our results provide the first evidence that both local stability and communities asynchronous dynamics drive regional stability of butterfly abundance, but withrelatively greater importance of the former component. We found that climatic factors (temperatureand precipitation) and spatial distance modulated the stabilizing effect of different facetsof biodiversity, mainly in a positive way. We found that functional β-diversity and the different facets of α-diversity were important drivers of maintaining regional stability. Wealso demonstrate that there is a relative change in the contribution of local and regional stabilizing processes depending on the dispersal ability of butterflies. Particularly, species withlow dispersal capacity have higher functional β-diversity and metapopulational andspatial asynchrony, which contributes to regional stability. On the other hand, communitiesof species with high dispersal capacity present greater α-diversity (taxonomic and functional), which results in a stronger contribution of local mechanisms on the stabilityof metacommunities. Overall, our results indicate that (i) structural and functional connectivity modulates the responses of taxa to environmental disturbances; (ii) the trend observedfor species with broad climatic tolerance and larger egg size, considering the different homogenization and differentiation scenarios, suggests that climatic extremes seemtobethe strongest filter in the structuring of butterfly communities and that larger egg sizemaybe associated with factors that positively influence larval survival and (iii) mobility changesthe relative importance of local and regional stabilizing processes. Furthermore, we emphasize the necessary consideration of multiple spatial scales to improve understandingof biodiversity change along disturbance gradients and their stabilizing effect, withdirect implications for conservation and management.