The Early Stages of Speciation in Amazonian Forest Frogs: Phenotypic Conservatism Despite Strong Genetic Structure

摘要: Phylogeographic perspectives incorporating multiple classes of characters, especially those relating to sexual signals, are promising for the elucidation recent evolutionary mechanisms driving speciation. Here, forest frogs were used as a model system access distinct stages in process differentiation. We studied 280 individuals assigned three species: Allobates paleovarzensis, A. nidicola and masniger. Samples collected at 20 localities arranged two study systems, along middle Amazon lower Madeira Rivers, Central Amazonia. Mantel tests, analyses molecular variance, spatial distribution haplogroups indicated that genetic variability, inferred from mitochondrial DNA marker, was determined by combination isolation-by-distance effects transposition large Amazonian rivers. These factors had contrasting relative influences each which also differed regarding estimated time major cladogenetic events. Pronounced population structure observed. However, multivariate discriminant function revealed phenotypic (morphological acoustic) divergence loosely related with differentiation did not successfully predict assignment groups. The observed variability showed important role drift diversification marker studied. conservatism among populations surprising view high structuring observed, indicates prevailing stabilizing selective forces signal morphological