Como a seleção natural atua na mancha umeral e na história de vida de Poecilia vivipara Bloch 1801 (Actinopterygii: Cyprinodontiformes)?

Abstract

Natural selection acts on phenotypic characteristics regardless of their genetic bases, resulting in changes that can be observed in a generation. These phenotypic changes are driven by sexual selection, which is an evolutionary mechanism responsible for the appearance of ornamental structures and extremely elaborate behaviors associated with preferences for certain types of signaling. Indicating the body condition, genetic or parental quality of the individuals who have. Based on the assumption of natural selection theory propose two hypotheses: (I) is directional selection on the standard length in populations of Poecilia vivipara ( II ) is directional selection of standard length attribute and the Total area of the humeral spot in populations P. vivipara. In this study, 406 individuals were collected and analyzed 366 in two campaigns, in January (Pools) and March (perennial river) 2015. Where investigated whether patterns of humeral spot P. vivipara, measuring their morphometric data through the program LAS (Leica Aplication Suite). It was observed at the end that sexual selection and predation by selection acts in determining phenotypes, directing the phenotypes to the extreme, but in the end the stabilizing selection is predominant.