Overall, these observations provide preliminary

clues on the functional significance of signals emitted by non-quantitative traits and their potential importance for intraspecific interactions. Based on these observations, Labra (2011) speculates about the possible effects of chemical interactions as drivers of sexual speciation in these lizards, and then concludes that these chemical-based interactions may explain the remarkable speciation rates of Liolaemus in general. On their Metabolism inhibitor own, these statements sound exciting. However, Labra’s conclusions seem to suffer from two main limitations: one primarily observational, and one primarily theoretical, which I regard as conceptually more important. Firstly, learn more Labra reaches her conclusion of sexual speciation in Liolaemus lizards by stating that rapid evolution of traits involved in mating can prevent (or replace) evolution of other traits, such as morphological

traits, as suggested by previous evidence observed in other organisms. She suggests that a similar scenario may explain the high speciation rates of Liolaemus, given that their ‘relative lack of variation’ in morphology and ecology may be the consequence of the rapid evolution of chemical communication systems in these lizards. However, this is a questionable statement that may result from her use of a very limited literature (she only cites Jaksic, Núñez & Ojeda, 1980; Mella, 2005) only involving a minor proportion of Liolaemus biodiversity restricted to central Chile. In contrast, broader-scale (in phylogeny, ecology and distribution) studies have consistently shown that these lizards have evolved substantial morphological and ecological diversity, expressed as large variation in body size, body shape, sexual dimorphism, use of microhabitats and of thermal environments, diets, life histories and dispersal potential (Cei, 1986, 1993; Harmon et al., 2003; Espinoza et al., 2004; Schulte

et al., 2004; Cruz et al., 2005; Pincheira-Donoso et al., 2007, 2008b, 2009; Pincheira-Donoso, 2011; Pincheira-Donoso & Tregenza, Ergoloid 2011). Therefore, regardless of whether chemical systems of communication have or have not rapidly evolved in Liolaemus, it is difficult to support the view that the evolution of these chemical traits have prevented or limited the evolution of morphological and ecological diversity in these lizards. Indeed, while abundant evidence involving a high number of Liolaemus species show that ecological and morphological diversity have evolved, only a few studies restricted to a few species have shown the extent of variation in chemical communication. Also, the only study investigating the extent of evolutionary lability of the precloacal glands that produce these scents in Liolaemus revealed a strong effect of phylogenetic history (Pincheira-Donoso, Hodgson & Tregenza, 2008a).