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    Variação na forma da cabeça em populações continentais e insulares no complexo Bothrops jararaca (Serpentes: Viperidae)
    (Universidade Federal de São Paulo, 2014-04-29) Gusmão, Rodrigo Blanques de [UNIFESP]; Sawaya, Ricardo Jannini [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)
    The beginning of morphological studies merges with the beginning of the biological studies, and was a central key in the proposition of the evolution by the means of natural selection by Charles Darwin. Islands are good models for evolutionary studies because they have known history. Bothrops jararaca species complex includes three insular endemic species and one species that occurs in continental areas and in some islands. The species complex is divided in two genetic clades occurring in allopatry, with a break in southern São Paulo. All described insular species to the group are related to the northern clade of continental populations of B. jararaca. Present work focus on the analysis of the head shape to verify the presence of a geographical structure and inter-specific divergences of B. jararaca complex. We have included populations from continental areas, Búzios Island, SP (B. sp.1) and Franceses island, ES (B. sp.2), besides B. insularis and B. otavioi. The head shape analysis was carried out on lateral view of the head using 15 landmarks analyzed after a procrustes superimposition. The Principal Component Analisys (PCA) and Discriminant Analysis showed that continental B. jararaca is the only species with significant sexual dimorphism for head shape. Mantel's correlations and Moran's index shows no spatial autocorrelation in males and only Moran's Index shows spatial autocorrelation in females. PCA shows relevant inter-specific divergence for head shape, which was significant by Canonical Variate Analysis (CVA) and discriminant analysis. Using a model that compares B matrix(between species) variance with W Matrix (within species) variances, we could find that natural selection might have played a central role in the head shape diversification in B. jararaca species complex, which was probably linked to diet differences between species. Our results show that the populations analyzed could be considered as distinct evolutionary entities.