Body+Size+and+Structure

__ Body size and structure __

The body size of a particular clade and subsequently many species is tightly linked to the biology of the lizard including its morphology, ecology, physiology and the history of the animal. Size can be altered as a result of the lizard’s overall breeding, behavioural habits and the available niche in its environment (Pianka, 1995). Habitat usage, environment and climate are important factors in the development of size related adaptations and evolution. In lizards and in particular the //Varanus//species three major habitat patterns determine the lizard’s size and these are whether the lizard is a terrestrial, arboreal or rock-dwelling species ( Collar //et al//. 2011) . Terrestrial lizards such as the Lace monitor (//V. varius)// and Komodo dragon (//V. Komodoensis)// tend to form larger lizards greater than one metre in length and rock-dwelling lizards tend to be less than one metre in size (Collar //et al//. 2011).



Morphological diversity and phenotypic diversity can also be closely linked with the body size of an individual. Greatest ecological and species diversity occurs within the Australian //Varanus// lizards. Stouter corpulent body physique is common in terrestrial large lizards, whereas a slender physique is common in rock-dwelling smaller lizards. Adaptive radiation has resulted in two different forms of //Varanus// lizards, those who have dwarfism and those with gigantism. Large monitors tend to be top predators in their habitat they occupy and smaller lizards tend to be prey (James, 1996). Large size in lizards can relate to a large home range and travel distance that is greater than a lot of other lizards (Green and King, 1978) //Varanus varius// is a powerful diurnal lizard that has a large elongated muscular body and a long forked tongue (Guarino, 2001).

The lace monitor is an example of a lizard that is a part of the clade that has developed giantism and reigns as one of the largest land mammals in Australia. The body length of the lizard ranges from 1.5 - 2m long for a fully grown lizard and infant lizards grow to full size within around two years from birth. Their extensive body size provides as a defence mechanism against other predators. Predators of the //Varanus varius// are limited but some include introduced species such as foxes and cats (Olsson //et al//. 2005).