Estruturação genética e relações de parentesco de golfinhos-de-dentes-rugosos no Atlântico Sudoeste

• Ano de defesa: 2024
• Autor(a) principal: Medeiros, Gabriela Ortolane
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal do Espírito Santo; BR; Mestrado em Biologia Animal; Centro de Ciências Humanas e Naturais; UFES; Programa de Pós-Graduação em Ciências Biológicas
• Palavras-chave em Português: Cetáceo; Delphinidae; Diferenciação genética; Matrilinearidade; Filopatria; Cetacean; Genetic differentiation; Matrilineality; Philopatry; Zoologia
• Link de acesso: http://repositorio.ufes.br/handle/10/18330

Because they are social organisms, it is common to see different social units forming in the short or long term in the same dolphin population. Associations like this can be formed by organisms that are related or unrelated. Rough-toothed dolphins are known for forming groups with few animals, usually between 10 and 20 individuals. Although it is classified as “Least Concern”, it is still a little-known species, and it is essential that we investigate the existence of kinship relationships in the coastal population of the Southwest Atlantic, since no studies have been found that address this aspect in the region. In this way, this study aims to describe the possible kinship relationships in the coastal population of Steno bredanensis, as well as continuing the investigations into genetic diversity that have already begun. Using the mitochondrial DNA control region (D-loop) and 10 microsatellite loci, we used samples collected by biopsy (n = 07), from strandings (n = 12) and D-loop sequences made available by the PMC-BS (n = 18). The ML-Relate and Colony programs were used to determine kinship relationships. The mitochondrial DNA sequences revealed three populations in the Southwest Atlantic Ocean (ES + RJ, São Paulo and Oceânica), two of which showed low levels of haplotypic and nucleotide diversity (ES + RJ: h = 0.074 and π = 0.0001; Oceânica: h = 0.400 and π = 0.0020). For the microsatellite loci, two populations were found to have moderate average observed and expected heterozygosity (Espírito Santo: Ho = 0.600 and He = 0.526; Ilha Grande-Sepetiba: Ho = 0.653 and He = 0.534). For the Espírito Santo population, full sibling, half sibling or parent/offspring relationships were found. On the other hand, the Ilha Grande-Sepetiba population showed half-sibling and parent/offspring relationships. The structuring results observed may be associated with micro-scale differentiation, where group configurations are formed due to resource specialization or site fidelity. The differences observed in the population differentiation indices for each marker indicate genetic dispersal influenced by sex. As for kinship relations, it has been suggested that females are more philopatric, while males are more transient. The results of this study are fundamental for assessing the effectiveness of conservation strategies and predicting the need for future interventions