CONICET | Buscador de Institutos y Recursos Humanos

Ecomorphological studies of lizards have explored the role of various26 morphological traits and how these may be associated with, among other things, habitat27 use. We present an analysis of selected traits of internal morphology of the hind limbs of28 Neotropical iguanian lizards and their relationship to habitat use. Considering that one of29 the most widely-held hypotheses relating to the origin of grasping is associated with the30 exploitation of the narrow-branch arboreal habitat, we include subdivisions of this31 designation as two of our ecologically-defined categories of habitat exploitation for32 analysis, and compare lizards assigned to these categories to the features displayed by33 terrestrial lizards. The influence of phylogeny in shaping the morphology of lizards was34 assessed by using the Comparative Method. K-values were significant for several35 osteological traits. Most of the K-values for the variables based upon muscle and tendon36 morphometric characters (13 out 21), by contrast, had values less than 1, suggesting that37 their variation cannot be explained by phylogeny alone. Results of our phylogenetic and38 conventional ANCOVA analyses reveal that the characters highlighted through the39 application of the comparative method are not absolutely related to habitat in terms of the40 categories considered here. It appears that the bauplan of the lizard pes incorporates a41 morphological configuration that is sufficiently versatile to enable exploitation of almost all42 of the available habitats. As unexpected as conservation of internal gross morphology43 appears, it represents a means of accommodating to environmental challenges by44 apparently permitting adequacy for all situations examined.45