Abstract
In this letter, we revisit a study we published in 2017, following comment in a paper by Marchesini et al. published in this volume. We provide some further analyses that help us to reinforce the original conclusions of our earlier paper, and to address the points raised by Marchesini et al. We conclude that the concerns raised in their review do not alter the inference we presented earlier, and we identify issues with analyses presented by Marchesini et al. that limit their utility. The key points of inference remain that this species in Europe shows remarkably low levels of diversity within populations and strong structure among populations which can be explained by a combination of natural and anthropogenic processes.