Velo-Antón, G., Lourenço, A., Galán, P. Nicieza, A. y Tarroso, P. Sci Rep 11, 9259 (2021). Our study shows that patterns of hybridization between S. salamandra subspecies are highly heterogeneous across space, thus emphasizing the role of environmental factors in shaping patterns of hybridization and reproductive isolation. This is best illustrated by the Cantabrian Mountains, which likely comprise an effective barrier to gene flow between the pueriparous S. s. bernardezi and larviparous S. s. bejarae. Despite the fact that prezygotic and postzygotic barriers were not detected in our study, it is unclear whether hybridization among these subspecies negatively affects survival and fertility of hybrids. Leer más.