Estudo das variações morfológica craniana e citogenética em Akodon cursor (Rodentia:Sigmodontinae) no Estado de Minas Gerais

• Autor(a) principal: Manduca, Edmar Guimarães
• Data de Publicação: 2008
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://locus.ufv.br/handle/123456789/2206
• topic: Morfologia craniana; Citogenética; Akodon cursor; Cranial morphology; Cytogenetics; Akodon cursor; CNPQ::CIENCIAS BIOLOGICAS::GENETICA::GENETICA ANIMAL

Akodon cursor is a sigmodontine rodent with wide distribution in the eastern of Brazil. It occurs from Pernambuco to Paraná presenting high levels of morphological and cytogenetic variation in their populations. Many efforts have been made in order to uncover the distribution patterns of different cytotypes and to distinguish the morphological forms of this species in relation to the others from the same genus. Morphologically the species has great internal and external similarity to other species of the genus. Cytogenetically distinguishes from others for having its diploid number ranging from 2n = 14, 15 and 16 and too for having one of the greatest chromosome polymorphisms among mammals. Populations of this species in the Atlantic Forest remnants of the State of Minas Gerais has been little explored or analyzed based in a reduced individuals number. In this way, the objective of this study was to evaluate the intra and interpopulation variation in skull and cytogenetics morphology of specimens of A. crusor collected in some areas in the state of Minas Gerais. Twenty measures have been taken for the establishment of cranial morphometric analysis. The descriptive and multivariate statistics were held to the view of the morphometric patterns. Cytogenetic analyses were used to view the polymorphims patterns intra and interpopulation of A. cursor in Minas Gerais State. The multivariate statistics showed a differentiation in cranial morphology between specimens of different areas along the shape axis. The cytogenetic methods allowed the view of polymorphisms intra and interpopulations that, according to the χ2 test, are in Hardy-Wienberg balance. The banding techniques C and Ag-NOR did not reveal differences between populations studied. The Parque Estadual da Serra do Brigadeiro possibly represents the population with higher altitudinal distribution of this rodent. The altitudinal factor may represent a variable to explain the observed difference in skull morphology in studied populations. The assessment of the population present in Parque Estadual da Serra do Brigadeiro and the addition of new areas with a bigger number of specimens will provide a new database for understanding the evolution of the species in morphological and cytogenetic terms.