Assessment of the Mass, Length, Center of Mass, and Principal Moment of Inertia of Body Segments in Adult Males of the Brown Anole (Anolis sagrei) and Green, or Carolina, Anole (Anolis carolinensis) Pierre Legreneur, 1,2 * Dominique G. Homberger, 3 and Vincent Bels 1 1 UMR 7179 du CNRS, De ´partement Ecologie et Gestion de la Biodiversite ´, Muse ´um National d’Histoire Naturelle, Paris, France 2 Centre de Recherche et d’Innovation sur le Sport, Universite ´ de Lyon, Villeurbanne, France 3 Department of Biological Sciences, Louisiana State University, Baton Rouge, Louisiana 70803 ABSTRACT This study provides a morphometric data set of body segments that are biomechanically relevant for locomotion in two ecomorphs of adult male anoles, namely, the trunk-ground Anolis sagrei and the trunk- crown Anolis carolinensis. For each species, 10 segments were characterized, and for each segment, length, mass, location of the center of mass, and radius of gyration were measured or calculated, respectively. The radii of gyration were computed from the moments of inertia by using the double swing pendulum method. The trunk- ground A. sagrei has relatively longer and stockier hin- dlimbs and forelimbs with smaller body than A. caroli- nensis. These differences between the two ecomorphs demonstrated a clear relationship between morphology and performance, particularly in the context of predator avoidance behavior, such as running or jumping in A. sagrei and crypsis in A. carolinensis. Our results provide new perspectives on the mechanism of adaptive radia- tion as the limbs of the two species appear to scale via linear factors and, therefore, may also provide explana- tions for the mechanism of evolutionary changes of structures within an ecological context. J. Morphol. 273:765–775, 2012. Ó 2012 Wiley Periodicals, Inc. KEY WORDS: squamates; ecomorph; locomotion, Anolis, jumping INTRODUCTION Anoles (Anolis spp.) represent one of the largest genera of lizard-like reptiles (Squamata) with over 400 species and occur on the American continents, including the Caribbean (Poe, 2004; Losos, 2009). This group is characterized by one of the greatest morphological, behavioral, and ecological diversity among arboreal tetrapods and has been used as a major model for analysing evolutionary processes in animal communities (Yang et al., 1974; Losos, 1994; 2009; Butler and King, 2004; Knouft et al., 2006). Anoles can be classified into various ecomorpho- logical groups based on the part of their habitat they use predominantly, such as the height above ground or the diameter of perches. Accordingly, these ecomorphs are designated as ‘‘grass-bush,’’ ‘‘trunk-ground,’’ ‘‘trunk,’’ ‘‘twig,’’ ‘‘trunk-crown,’’ and ‘‘crown-giant’’ (Williams, 1972). These basic eco- morphs have been used to study the interactions between locomotor performance and ecological radia- tion in tetrapods (Pounds, 1988; Losos, 1990a; 2009; Irschick and Losos, 1998; Mattingly and Jayne, 2005). So far, various species of anoles have been used to analyze the functional and ecological signifi- cance of some of the morphological, locomotor, and ecological traits within a phylogenetic context (Toro et al., 2004; Toro et al., 2006; Vanhooydonck et al., 2006b). However, all these studies provide no quan- titative information on the force production mecha- nisms by the musculo-skeletal systems in response to the physical constraints of the environment. Among anoles, the trunk-ground Brown Anole (Anolis sagrei) and the trunk-crown Green Anole (Anolis carolinensis) have been used to analyze the functional consequences of variation in the mor- phology of the limbs (e.g., limb length), locomotor capabilities (e.g., jumping and running), and char- acteristics of their environment (Bels et al., 1992; Spezzano and Jayne, 2004). The two species differ in the relative frequency of walking and jumping in their locomotion behavior (Losos, 2009) to catch Additional Supporting Information may be found in the online version of this article. Contract grant sponsor: Mae ¨lle Deloche; Contract grant sponsor: Claude Meunier; Contract grant sponsor: Lionel Reveret and Paul- Antoine Libourel (ANR project Kameleon); Grant number: ANR-05- MMSA0002-02 ‘‘Masse de Donne ´es’’. *Correspondence to: Pierre Legreneur, UMR 7179 CNRS-MNHN, 57 Rue Cuvier, Case postale 55 F 2 75231 Paris Cedex 5 France. E-mail: pierre.legreneur@univ-lyon1.fr Received 22 June 2011; Revised 30 January 2012; Accepted 18 February 2012 Published online 28 March 2012 in Wiley Online Library (wileyonlinelibrary.com) DOI: 10.1002/jmor.20022 JOURNAL OF MORPHOLOGY 273:765–775 (2012) Ó 2012 WILEY PERIODICALS, INC.