Baited pitfall traps were used to sample the lizard fauna at Birdlings Flat on Kaitorete Spit, Canterbury. Four species had been recorded previously from this area; Leiolopisma maccanni Patterson and Daugherty, Leiolopisma nigriplantare polychroma Patterson and Daugherty, Leiolopisma lineoocellatum (Dumeril and Dumeril) and Hoplodactylus maculatus (Gray). Three of these species (L. maccanni, L. n. polychroma and H. maculatus) were captured during the course of the study. The aim of this present study was to examine the nature of the ecological relationship among these three species at Birdlings Flat. Capture data indicated that L. maccanni was almost entirely confined to the dunelands while L. n. polychroma was associated exclusively with shrublands on old dune ridges behind the sand dunes. H. maculatus' distribution encompassed both of these major habitats. Separation on the basis of habitat was thought to be the most important niche variable for these two diurnal skinks. There was some temporal separation in activity of these two species, with L. maccanni active earlier in the day than L. n. polychroma. However, there was a high degree of overlap in the activity periods of these two species. Temporal differentiation between the nocturnal gecko H. maculatus and the two diurnal skinks is thought to be an important means by which these species coexist. The most common prey items consumed by all three species were Diptera, Araneae, C. propinqua seeds, Hemiptera, unidentified arthropod eggs, Coleoptera and Hymenoptera. Dietary differences between the two skink species were apparent although these differences appeared to be related to the preferred habitats of the respective species. Density estimates for L. maccanni varied between 1050/ha and 1850/ha while L. n. polychroma density varied between 200/ha and 400/ha. The density of H. maculatus was not calculated but appeared to be intermediate to the density of the two skink species. The apparent disappearance of L. lineoocellatum from an area where they were once relatively common is cause for concern. There is no obvious reason for this decline although it may be related to the combined impacts of predation, collection and habitat disturbance.

Thesis (Ph.D.) -- Flinders University, School of Biological Sciences. / Typescript (bound). Includes bibliographical references. Also available online.

Thesis (M.S.)--Missouri State University, 2008. / "August 2008." Includes bibliographical references (leaves 18-20) and (leaves 36-39). Also available online.

No description available.

This study focused on the interactions between small skinks and their major predators/competitors (birds) and prey (arthropods) in core and edge areas of small, long established remnant Cumberland Plain woodlands of Richmond, New South Wales, Australia. Eight study sites were selected (4 edge and 4 core) within the peri-urban environment to compare the abundance and diversity of small skinks, birds and arthropods. Of the three taxa, only arthropods maintained a similar abundance and diversity between edge and core areas. Birds and skinks were either in lower numbers in the perimeter areas (skinks), or were interior/perimeter specialists (birds). Arthropod diversity and abundance of preferred skink prey, was also examined. It was concluded that the distribution of arthropod prey was similar between core and edge areas, and therefore, was not considered to have an influence on small skinks’ ability to inhabit edges. However, large, aggressive/noisy birds (including skink and small bird predators) dominated edge areas. Those birds encountered in the edge foraged in a variety of niches, such as on the ground or they swooped from vantage points. This, coupled with other anti competitor behaviour (e.g. noise, aggression, flocking), placed these birds in proximity to skinks in the edge areas. However, as most of these birds were also predators of skinks, it was concluded that the evidence supported a predator/prey relationship in the perimeter area, rather than a competitive one. This was supported by predation rates on skinks, using decoys. Birds preyed on small skink in greater numbers in the perimeter of woodland remnants than in their interior. This predation pressure was sustained throughout the year. It was concluded that predation and/or displacement of skinks and small birds resulted in lower numbers being observed in edge compared to core areas. This study demonstrated that old, small remnants not continually exposed to major disturbances (e.g. logging, agricultural practices) can re-establish stability in terms of environmental conditions. However, a stable environment or a single taxonomic group does not necessarily predict the response individual taxa will have to edge habitats and that this can alter the interactions between dependent groups such as prey/predator or competitors. . / Doctor of Philosophy (PhD)

The flora of Aotearoa/ New Zealand has evolved in association with birds and lizards as the dominant frugivores and seed dispersers. There is a wide range of ripe fruit colours within the native fleshy-fruited plants spanning the visible light spectrum from red to violet, with the notable exception of green. The evolution of fleshy-fruit and fruiting related trait, may be a result of the selection pressures exerted by different frugivore guilds. This study was conducted to ascertain if endemic diurnal lizards, Oligosoma species (Scincidae: Lacertilia), display features associated with visual based foraging, colour sensitivity and colour preferences, which are necessary conditions to infer a co-evolutionary mutualism between fleshy-fruited plant species and lizards as seed dispersers, which may have influenced the evolution of fruit colour. Many lizards have exceptional colour vision, with the ability to see a wide range of the visual light spectrum from short wave ultra violet to long wave red. They are able to discriminate all aspects of colour: hue, brightness and saturation. Fruit colour within Coprosma (Rubiaceae), is extremely variable, between and within species. The study of fruit colour preferences within this genus and particularly within species with polymorphic fruit colour provides a valuable comparison of frugivore preference to fruit with little inter and intraspecific variation, therefore minimising potentially confounding factors due to phylogeny. Fruit-colour choice experiments were conducted offering fruit from two colour categories based on postulated frugivore preferences; red and red orange fruit has been associated with avian frugivores whilst white and pale fruit has been associated with lizard frugivory in New Zealand. Experiments were conducted both ex-situ, in environmentally controlled laboratories and in-situ at Macraes Flat, Otago. Pilot trials indicated that the background colour on which fruit were presented was important in fruit choice and consequentially, all fruit were offered on a background which provided contrast to both fruit colour categories. The laboratory trials showed some weak evidence for a preference of white and pale blue fruit however, in-situ trials showed a strong preference for white over red fruit. Field studies were conducted to ascertain the composition of fleshy-fruit in the diets of lizards and the results were consistent with those expected for a generalist omnivore; many of the small fruits available to lizards were consumed however, the results indicated that plant abundance does not adequately explain fruit consumption at this field site. A preference index showed that white and pale fruited plants, Melicytus alpinus and Coprosma spp., were preferred over more abundant orange and red fruited plants. Fruit odour was investigated to determine if fruit choice was mediated primarily by visual cues as opposed to odour cues. Fruit choice trials with the fruit concealed from view indicated that fruit choice was based primarily on visual cues in Oligosoma skinks. It is concluded that lizards demonstrate the necessary conditions to infer that as frugivores, they may have influenced the evolution of fruit colour and that within the open habitats of Aotearoa/ New Zealand, the shrubs, particularly the divaricate shrubs may have provided sufficient environmental conditions to establish a mutualism between plants and lizards resulting in the evolution of small, white and other low chroma fruits.

The endemic landbirds of the Seychelles granitic islands have suffered considerable losses due to predation by introduced rats and cats and extensive habitat destruction. With less than 100 individuals, the Critically Endangered Magpie Robin Copsychus sechellarum Newton, faces the greatest risk of extinction. Translocations to three predator-free islands, Aride, Cousin and Cousine, have provided valuable opportunities for gaining insights into the ecology of the species. Of particular interest are links between the Magpie Robin, endemic skinks Mabvya spp., ground-living invertebrates and seabird colonies. Magpie Robin faecal pellet and skink gut content analysis demonstrated a high degree of dietary overlap between the species. A widespread exotic cockroach Pycnoscelus indicus was the favourite prey item for each species. However, behavioural observations and a dietary choice experiment indicated that there is no significant competition for food during the main seabird breeding season. Invertebrate sampling on Cousine identified 52 species which were available in all habitat types currently in use or those considered suitable for the Magpie Robin. Seabird and skink density counts on Cousine demonstrated the considerable magnitude of vertebrate organic food also available. Invertebrate sampling results on Cousin and Cousine were used to determine territory quality and the carrying capacity of each island for the Magpie Robin. While most seabirds are not breeding, skink survival depends on invertebrate abundance. M. wrightii weight declined throughout this period but that of M. sechellensis remained fairly stable. The data were insufficient to conclude that inter-specific competition for food exists between M. sechellensis and the Magpie Robin during this period. Further expansion of the Magpie Robin population depends on eradicating mammalian predators from other islands and maximising the potential carrying capacities of those already supporting the species. / Thesis (M.Sc.)-University of Natal, Pietermaritzburg, 1998.

Further clarification of the taxonomic and phylogenetic relationships of Eumeces gilberti and Eumeces skiltonianus is achieved by the comparisons of the skull, mandible elements, and the anterior myology of these two species. Figures are provided to compliment the descriptions. The study confirms their close relationship and few differences are observed. E. skiltonianus, however, appears to have more anatomical plasticity which suggests that E. gilberti may have arisen from the former.

A qualitative and quantitative comparison of the vomeronasal organ was made of the autarchoglossan lizards: Scincella lateralis, Eumeces fasciatus, Eumeces inexpectatus, and Ophisaurus ventralis, and the ascalobotans: Sceloporus undulatus, Hemidactylus turcicus, and Xantusia vigilis. As judged by the thickness of the vomeronasal sensory epithilium the vomeronasal organ was most highly developed in Ophisaurus venteralis and least developed in Sceloporus undulatus. A comparison of the relationship between the vomeronasal sensory epithelium thickness and vomeronasal capsule length of autarchoglossans and ascalobotans supports the hypothesis that the vomeronasal organs of of autarchoglossans are larger than ascalobotans. However, a comparison of mean residuals for the species utilized in this study indicate that the relative size of the vomeronasal organ may be related to ecology as well as systematic relationships. Lizards that are secretive, fossorial, nocturnal or crepuscular have a tendency to have relatively well developed vomeronasal organs as measured by the thickness of the vomeronasal sensory epithelium, and lizards that are diurnal, visually oriented, and aboreal generally have smaller, less developed vomeronasal organs. Scincella lateralis responds to both visual and chemical cues of prey. A visual stimulus is associated with an increased rate of tongue flicking, orientation to the prey, and attack behavior. Chemical cues are unimportant when the visual cue (movement) is present. When prey are non-moving or dead, chemical cues enable the lizard to distinguish potential prey from inanimate objects. Vision and the chemical senses interact in a complex way to form the predatory repertoire of Scincella lateralis. Lizards may adopt one of two basic foraging strategies; an active foraging strategy or a sit-and-wait strategy. Lizards in the active foraging mode use both visual and chemical cues to detect moving or non-moving prey. A lizard in the sit-and-wait mode uses vison to detect prey movement. However, if the prey eludes capture after a lizard in the sit-and-wait mode begins its predatory attack, chemical cues may be used to track or identify the prey. / Master of Science

In this thesis, I investigate the phylogeny and evolution of Lerista, a clade of more than 75 species of scincid lizards, distributed in arid, semi-arid, and seasonally dry habitats throughout Australia. Among extant tetrapods, Lerista is exceptional in comprising a large number of closely-related species displaying prodigious variability of body form; several species possessing well-developed, pentadactyl limbs resemble typical non-fossorial scincids in body proportions, while many other species exhibit varying degrees of limb reduction and body elongation, including two that are highly elongate and entirely limbless. The extensive variation in limb morphology observed among species, incorporating at least 20 distinct phalangeal configurations, has prompted some authors to identify Lerista as the best available model for studying limb reduction in squamates. Nonetheless, lack of a well-resolved phylogeny has impeded investigation of the pattern and mode of limb reduction and loss within the clade. The primary goal of my research was to furnish a comprehensive phylogenetic hypothesis for Lerista, enabling more sophisticated study of the evolution of limb morphology and body form in this clade than has previously been possible. A recent phylogenetic analysis of mitochondrial DNA sequences for a series of Australian Sphenomorphus group scincids (including two species of Lerista) recovered several well-supported, major clades, although these were generally separated by relatively short branches associated with low support values. Applying a recently described methodology for inferring lineage-level polytomies, I use ATP synthetase-β subunit intron sequences and the existing mitochondrial DNA data set (with sequences for additional taxa) to assess the hypothesis that the poorly resolved basal relationships within the Australian Sphenomorphus group are a consequence of the major clades having originated essentially simultaneously. Phylogenetic analyses of the separate mitochondrial DNA and intron sequence data reveal a number of congruent clades, however, the relationships among these clades indicated by the two data sets are generally incongruent. Although this may be partly ascribed in to error in estimating phylogenetic relationships due to insufficient data, some incongruence is evident when uncertainty in inferred relationships is allowed for. Moreover, the congruent clades are typically separated by very short branches, several having a length insignificantly different from zero. These results suggest that initial diversification of Australian Sphenomorphus group scincids was rapid relative to the substitution rates of the mitochondrial DNA and intron fragments considered, if not essentially simultaneous. The pattern and rate of limb reduction in Lerista are investigated, employing a nearly complete phylogeny inferred from nucleotide sequences for a nuclear intron and six mitochondrial genes. Ancestral digit configurations reconstructed assuming this phylogeny indicate at least ten independent reductions in the number of digits from a pentadactyl condition, including four independent losses of all digits, three from pentadactyl or tetradactyl conditions. At the highest rate, complete loss of digits from a pentadactyl condition is estimated to have occurred within no more than 3.6 million years. Patterns of digit loss for the manus and pes are consistent with selection for preserving hindlimb utility as the limbs are reduced, and suggest that intermediate digit configurations exhibited by extant species do not represent transitory stages in a continuing process of limb reduction. An increase in the relative length of the body is demonstrated to precede digit loss in lineages experiencing substantial reduction of the limbs, supporting the hypothesis that limb reduction and loss is a consequence of the adoption of lateral undulation as a significant locomotory mode. However, less extensive limb reduction may proceed in the absence of body elongation, perhaps due to a decrease in absolute body size. The exceptionally high frequency and rate of limb reduction in Lerista emphasise the potential for rapid and dramatic evolutionary transformation of body form in squamates. The substantial divergence of relative limb and body length evident within Lerista is more readily explained by the correlated progression model of phenotypic transformation than the independent blocks model. At each step in the attainment of a limb-reduced, elongate body form, alterations to the relative length of the limbs are accompanied by changes in relative snout-vent length (or vice versa) enabling the maintenance of locomotory ability. Nonetheless, some dissociation of hindlimb reduction and body elongation is possible, emphasising the potentially variable intensity of functional constraints and, accordingly, that the independent blocks model and correlated progression are extremes of a continuum of models (each invoking a different degree of functional integration) and do not describe discrete categories of phenotypic change. An increase in the extent of seasonally dry and arid habitats coincident with the origination of Lerista would have facilitated limb reduction and body elongation by furnishing an environment conducive to the adoption of fossorial habits, however, trends toward a limbless, highly elongate body form may be attributed primarily to the very low probability of re-elaborating reduced limbs. Such asymmetry in the probabilities of possible phenotypic changes may be a significant cause of evolutionary trends resulting in the emergence of higher taxa. / Thesis (Ph.D.) -- University of Adelaide, School of Earth and Environmental Sciences, 2008