Thesis (M. Phil.)--University of Hong Kong, 2002. / Includes bibliographical references (leaves 70-80).

published_or_final_version / Ecology and Biodiversity / Master / Master of Philosophy

published_or_final_version / Zoology / Master / Master of Philosophy

Made available in DSpace on 2014-12-17T14:33:05Z (GMT). No. of bitstreams: 1 PauloALF_DISSERT.pdf: 2064193 bytes, checksum: f7bd272b82440f00076ae87259d903f5 (MD5) Previous issue date: 2011-05-05 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The fishes of the order Perciformes are characterized as an important model for understanding the genetic structure of marine populations, because besides they present examples of conservation chromosomal, also they present the karyotype diversification for some groups. Gobiidae family is the most specious in the marine environment. Among its representatives, many species are part of a cryptic fauna little noticed and studied, a wide distribution with behavioral and reproductive characteristics, that make them conducive to the action of biogeographical barriers. Morphologically this family presents reduced body structures through simplification and regressions. Despite their importance in evolutionary inferences, cytogenetics data are incipient facing their species diversity, especially with western Atlantic species. In order to estimate the evolutionary diversity in Gobiidae, it were developed cytogenetic analysis and the standards body, through geometric morphometrics in five species on the Brazilian coast, Coryphopterus glaucofraenum, Bathygobius mystacium, B. soporator, Ctenogobius smaragdus e C. Boleosoma. The data show significant karyotype and morphological diversity among the species. The pericentric inversions and mergers play an important role in chromosomal evolution of this family, causing karyotypic structural and numerical differences in all species. Karyotypic and morphological comparisons among geographic samples of B. soporator from the coast of Maranh?o, Rio Grande do Norte and Bahia showed cytogenetics patterns commons, but different morphological patterns. A sample from the Atol das Rocas revealed conspicuous morphological and karyotypic differentiation of another continental populations, confirming the presence of a new island species. The approaches done reveal diversification consistent with characteristics of a group of low vagile and largely able to environmental selection due from peculiar ecological requirements / Os peixes da ordem Perciformes caracterizam-se como um modelo importante para o entendimento da estrutura gen?tica de popula??es marinhas, pois apresentam tanto exemplos de conserva??o cromoss?mica como de diversifica??o cariot?pica para alguns grupos. Gobiidae ? a fam?lia mais especiosa no ambiente marinho. Entre seus representantes, muitas esp?cies fazem parte de uma fauna cr?ptica pouco percebida e estudada, apresentando ampla distribui??o com caracter?sticas comportamentais e reprodutivas que as tornam prop?cias ? a??o de barreiras biogeogr?ficas. Morfologicamente esta fam?lia apresenta estruturas corporais reduzidas atrav?s de simplifica??es e regress?es. Dados citogen?ticos, apesar da import?ncia em infer?ncias evolutivas, s?o incipientes frente sua diversidade de esp?cies, sobretudo para esp?cies do Atl?ntico Ocidental. Visando estimar a diversidade evolutiva em Gobiidae foram desenvolvidas an?lises citogen?ticas e dos padr?es corporais, atrav?s de morfometria geom?trica, em cinco esp?cies presentes no litoral brasileiro, Coryphopterus glaucofraenum, Bathygobius mystacium, B. soporator, Ctenogobius smaragdus e C. Boleosoma. Os dados obtidos demonstram marcante diversidade cariot?pica e morfol?gica entre as esp?cies. As invers?es peric?ntricas e fus?es desempenham papel importante na evolu??o cromoss?mica desta fam?lia, ocasionando diferen?as cariot?picas estruturais e num?ricas em todas as esp?cies. Compara??es cariot?picas e morfol?gicas entre amostras geogr?ficas de B. soporator provenientes do litoral do Maranh?o, Rio Grande do Norte e Bahia evidenciaram padr?es citogen?ticos comuns, mas padr?es morfol?gicos diferentes. Uma amostra proveniente do Atol das Rocas revelou consp?cua diferencia??o cariot?pica e morfol?gica das demais popula??es continentais, confirmando a presen?a de uma nova esp?cie insular. As abordagens empregadas revelam diversifica??es compat?veis com um grupo com caracter?sticas de baixa vagilidade e amplamente sujeito a sele??o ambiental decorrente de exig?ncias ecol?gicas peculiares