When is a hybrid a hybrid? A counter-reply to Wallace et al.

In a reply to a brief citation of their paper (Wallace et al . 2004), Wallace et al . (2006) re-analyse their data using the same methods as we did (Engel et al . 2005) to conclude again that an ecad of the brown alga Fucus sp., which occurs only in a particular type of habitat, was a hybrid. While we wholly agree that the ecad individuals (called ‘muscoides-like’) may be putative hybrids, their conclusions were — and remain — confounded with other, alternative explanations. Here, in response to their Reply (Wallace et al . 2006), we wish to clarify our reservations more fully and offer some reflections on identifying hybrids in species complexes