Thesis (Ph. D.)--University of Texas at Austin, 2000. / Vita. Includes bibliographical references (leaves 378-394). Available also in a digital version from Dissertation Abstracts.

[Truncated abstract] In ecomorphological or ecophysiological studies, variation in `design? traits (e.g. size, morphology and physiology) is thought to determine variation in ecologically-relevant performance traits, which in turn determines fitness in a particular habitat (Arnold 1983). Thus, natural selection is thought to act most directly on intermediate traits such as measures of locomotory performance. This thesis examined this process in the closely related group of Australian varanids lizards (Squamata: Varanidae). Phylogenetically, varanids are divided into three major clades. Size (mass and snout-to-vent length) is strongly correlated with these three clades. Two clades, (Gouldii and Komodoensis) are large, while the third clade (Odatria) has a smaller body size. Thus, there is considerable variation in size for various species. Size varied for species by three orders of magnitude. Size is also related to two ecological characteristics, foraging mode and habitat openness. Widely-foraging species were larger than sit-and-wait strategists, while species from open habitats were larger than species from semi-open or closed habitats. However, given the tight link between size and phylogeny we cannot separate adaptation of size to ecological traits from that of phylogenetic patterns. Of interest throughout this thesis was how variations in design (e.g. morphology and physiology) were related to ecological characteristics. Since body size also influences many of these morphological and physiological characteristics it is often necessary to remove the effects of size. Three design traits were examined in detail: body dimensions, vertebral number and metabolic rates. …Curiously, no performance variable linked differences in size-free body dimensions to retreat sites. This suggests that there is either a direct link between design and ecology (e.g. dorso-ventral compression), or some unmeasured performance variable related to retreat site. Given that most performance traits are thought to involve kinematic movements of the hindlimb limb and pelvis, and these were not best related to retreat site, then a direct link between design and ecology with respect to retreat site seems possible. In summary, this thesis provides evidence not only for links between design and ecology mediated by locomotory performance traits, but also direct links between design and ecology, for Australian varanid lizards.

Thesis (Ph.D.)--Edith Cowan University, 2006. / Submitted to the Faculty of Computing, Health and Science. Includes bibliographical references.

Learning in reptiles has been studied with a variety of methods and included numerous species. However, research on learning in lizards has generally focused on spatial memory and has used only a few species. No research has specifically investigated and documented the use of visual discrimination in monitor lizards. The ability of monitor lizards (Varanus spp.) to discriminate between visual stimuli was investigated. Subjects were tested on acquisition and two reversals of a discrimination task between black and white stimuli. A food-choice procedure was used to determine if consistent rankings of food items could be determined using a multiple-stimulus choice procedure. The functional value of the rankings was assessed using a progressive ratio technique. The subjects formed stable food preferences, which were reflected in increased response requirement completed for preferred items and subjects did successfully learn the initial discrimination task and the following reversals.

Diphyllobothriidean tapeworms are well-known parasites of mammals including man, but species parasiting in reptiles are much less known. These tapeworms belong to three genera (Bothridium, Duthiersia, Scyphocephalus) of the family Solenophoridae and are characterized by their unique scolex morphology. They occur in the intestine of varanid lizards and snakes. All three genera are known from Asia, two from Africa (Bothridium and Duthiersia) and one from Australia and South America (Bothridium). Individual genera are well characterised, but species composition of these genera is not well understood. This study surveyed available literary data on the genera Duthiersia and Scyphocephalus and provides new information based on new collected material from Africa and Southeast Asia and material deposited in helminthological collections.