The gut contents of 936 skinks, representing 15 species resident in south-eastern Australia, were examined. Multicategorisation of food items reveals that a wide variety of plant and invertebrate material is ingested, the proportions and types of which appear to be dependent upon several criteria. All species investigated are opportunistic and widely foraging generalists, although important determinants of food selection appear to be the size of the lizard and its vertical distribution. When the diets of individual species are amalgamated according to suprageneric groups, certain dietary traits emerge. Egernia-group species, which are relatively large, are generally herbivorous, with the degree of herbivory correlated directly to body size. Smaller species of the Leiolopisma (Eugongylus) and Sphenomorphus groups mainly eat insects.

Eleven sites, representing different successional stages of Eucalyptus regnansdominated forest in the Central Highlands of Victoria, were selected to identify potentially important habitat variables for heliothermic reptiles, three species (Eulamprus tympanum, Niveoscincus coventryi, Pseudemoia spenceri) of which were common at these sites. Analyses reveal that many forest attributes are strongly correlated with stand age and that some are significant habitat variables for some of these species. 'One-at-a-time' modelling of habitat variables reveals that counts off. tympanum are most strongly correlated with the proportion of grass as substrate (-ve), moss cover of logs (-ve) and litter depth (+ ve); A^. coventryi counts are most significantly related to litter depth (-ve), numbers of logs (-ve), log diameter (-ve), the proportion of bare ground as substrate (-ve) and length of sunny patches (+ ve); P. spenceri counts are most significantly related to the number of sunny patches ( -ve) and moss cover of logs ( -ve). The total reptile count is most significantly correlated with stag diameter ( -ve) and log diameter ( -ve). Predictive equations for each of the common species are also presented, using measured habitat variables, and these, along with 'one-at-a-time' models, indicate that a number of factors determine reptile occurrence or abundance and that no single predictor variable is apparent.

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Determining mutation signatures is standard for understanding the etiology of human tumors and informing cancer treatment. Multiple determinants of DNA replication fidelity prevent mutagenesis that leads to carcinogenesis, including regulation of free deoxyribonucleoside triphosphate (dNTP) pools and the repair of base mismatches. We utilized a targeted deep-sequencing approach to determine mutational signatures associated with mismatch repair (MMR) pathway defects. By combining rnr1 and msh mutations to increase dNTP levels and alter the mutational load, we observed previously unreported specificities of Msh2-Msh3 and Msh2-Msh6. Msh2-Msh3 is uniquely able to direct repair of G/C single base deletions in GC runs, while Msh2-Msh6 specifically directs repair of substitutions at G/C dinucleotides. We also identified broader sequence contexts that influence variant profiles in different genetic backgrounds and found that there was not necessarily a simple additive relationship of mutation profiles in double mutants. Our results have implications for interpreting mutation signatures from human tumors, particularly when MMR is defective.

Analysis of the number and volume of food items in the guts of the scincid Leiolopisma entrecasteauxii collected monthly from a rocky grazed site at Dreeite (38�11'S., 143�31'E.) on the volcanic plains of south-western Victoria revealed the species to be an opportunistic insectivore. Rank correlation analysis of the number of invertebrate taxa trapped monthly at the site revealed a significant (<0.05) overall association between potential and actual prey and little prey selectivity. Seasonal analysis of diet indicated the dominant prey taxa to be commutable throughout the year, confirming the opportunistic nature of feeding in L. entrecasteauxii. Marked fluctuations in the lizards' monthly food volume were intimately related to the energy demands associated with the various stages of their reproductive cycle. Both males and females maximised food intake just before the mating period, February-May. Food consumption was lowest during the coldest months when the female was overwintering the sperm. The females' food consumption increased during August, just before rapid follicular development and fertilisation by sperm in September-October.