Species arguments: clarifying competing concepts of species delimitation in the pseudo-copulatory orchid genus Ophrys

We are surprised that our recent comparative study of the micromorphology of all species of the European orchid genus Ophrys L. (Bradshaw et al., 2010) has attracted wide-ranging criticism (Vereecken et al., 2011) from a well-established group of researchers who, for the sake of brevity, we will term ‘ethologists’ (ethology: ‘the science of character …; the scientific study of the function and evolution of animal behaviour’). Our surprise stems from the decision of the authors to direct largely conceptual criticisms at a paper that is dominantly empirical, when we had in fact provided similar but more conceptually oriented targets that specifically addressed the systematics of Ophrys (e.g. Bateman, 2001; Devey et al., 2008; Bateman et al., 2003, 2010). Nonetheless, we welcome the opportunity to further explain the rationale underlying our views on adaptation, speciation and species delimitation in Ophrys. The core argument from Vereecken et al. (2011) is that the perspective expressed in Bradshaw et al. (2010) and associated papers is ‘too simplistic and speculative and misrepresents the current state of understanding of Ophrys ecology and evolution’. We were able to distil from the text of Vereecken et al. (2011) eight specific criticisms. The first of these is not explicitly numbered here as it is merely contextual: they begin their critique by arguing that our paper overlooked important historical references regarding issues such as the ecology and evolution of Ophrys and the colour vision of bees. Given that the paper of Bradshaw et al. (2010) spans 37 published pages and includes 110 references, it is not surprising that we were discouraged from adding further details or expanding our treatment of conceptual issues touched upon in the Introduction and Discussion of our paper. Selection of exemplar references was an inevitable constraint, although we were careful to cite reviews of the relevant historical literature (e.g. Kullenberg, 1961; Devillers & Devillers-Terschuren, 1994).