| isolation by distance, not incipient ecological speciation, explains genetic differentiation in an andean songbird (aves: furnariidae: cranioleuca antisiensis, line-cheeked spinetail) despite near threefold body size change across an environmental gradient. | during the process of ecological speciation, reproductive isolation results from divergent natural selection and leads to a positive correlation between genetic divergence and adaptive phenotypic divergence, that is, isolation by adaptation (iba). in natural populations, phenotypic differentiation is often autocorrelated with geographic distance, making iba difficult to distinguish from the neutral expectation of isolation by distance (ibd). we examined these two alternatives in a dramatic case ... | 2018 | 29134710 |