However, those studies lack a proper control to clarify what ‘high disparity’ really means. Let us illustrate this by comparing Liolaemus with Varanus lizards, a genus with fewer species (<70 sp), but with a wider geographical distribution (Africa, Australia and Asia; Pianka & King, 2004) than Liolaemus, which is restricted to the southern part of South America. The snout–vent lengths of Varanus species Crizotinib cell line range from 7 to 155 cm (Pianka &

King, 2004; Collar, Schulte & Losos, 2011), while in Liolaemus this ranges from 3.5 to 11.5 cm (Espinoza, Wiens & Tracy, 2004; Schulte et al., 2004; Pincheira-Donoso et al., 2008a; Labra, Pienaar & Hansen, 2009). Varanus species can be herbivores, carnivores or omnivores, and they can be terrestrial, arboreal or aquatic (Pianka & King, 2004). In contrast, most Liolaemus are insectivorous/omnivorous, very few are strictly herbivores and there are no strict carnivores (Espinoza et al., 2004; Vidal & Labra, 2008; Pincheira-Donoso, Scolaro & Sura, 2008b). In addition, most Liolaemus are saxicolous or ground-dwellers, very few Small molecule library order live in trees or shrubs, and there are no aquatic

or semiaquatic species (Schulte et al., 2004; Pincheira-Donoso et al., 2009). Finally, the thermal physiology of Liolaemus seems highly conservative across species even considering the wide range of habitats they encounter (Labra et al., 2009). In view of all this information, I cannot agree with Pincheira-Donoso’s criticism on this point. However, even if we were to accept the claim of high ecological and morphological disparity in this genus, there are cases of closely related and syntopic Liolaemus species that have similar ecology, morphology and behavior. Certainly, cases like these present a valuable opportunity

to investigate whether species recognition plays a role in maintaining 上海皓元医药股份有限公司 reproductive isolation between Liolaemus species. The verification of chemical species recognition in some species (Labra, 2011), together with ample evidence for the importance of chemical communication in the genus (Labra, 2008a, b ), make it plausible that speciation may be facilitated by the fast evolution of chemical sexual signals in the absence of variation in morphology or ecology (Morrison & Witte, 2011; Campagna et al., 2012). I am not implying that sexual speciation would prevent or limit morphological evolution and ecological adaptation, as Pincheira-Donoso assumes. The hypothesis simply predicts that Liolaemus species diversity is higher than what one would expect from ecological adaptation alone, and perhaps that the role of alternative sensory modalities (e.g. vision) in sexual selection would be small. Rapid evolution of chemical communication systems is a key element of my hypothesis.