A diversidade genética, mas não a fenotípica, é determinada pelas distâncias geográfica e climática no uirapuru-de-coroa-azul

Abstract

Investigating parallel roles of geography and environmental heterogeneity in diversification provides insights on how neutral and selective forces drive the evolution of biological systems. Here, we investigate whether geographic and climate variation explains either genetic or phenotypic variation, along with the distribution of the Blue-crowned Manakin (Lepidothrix coronata), a polychromatic bird species broadly distributed in the Neotropics. We tested the hypotheses of isolation either by distance, environment, and adaptation through an integrative approach using genetic, colorimetric, geographic, and climatic data. Through multiple matrix regression with randomization and Mantel correlation statistics, we tested whether intraspecific genetic or phenotypic diversity associates with variation in geographic and climatic distances among localities. Genetic and colorimetric distances were not correlated, and spatial autocorrelation in climatic data was low. Genetic distances were explained by geographic, climatic, and least environmental cost distances. Such results conform to predictions of isolation by distance and environment hypotheses, whereas coloration did not vary significantly with geographical or climatic distances. Our results suggest a combined effect of genetic drift and ecological forces in the diversification at the regional scale, and that both stochastic and deterministic processes may operate at a local level in the evolution of adult male plumage coloration.