Observations on sperm morphology from most species of murid rodents from New Guinea and the Solomon Islands, based on light microscopy, are presented. Transmission electron microscopy of spermatozoa for three species in two genera are also given. All Rattus species, Melomys lanosus, M. rattoides, Lorentzimys nouhuysi and Coccymys ruemmleri have sickle-shaped sperm heads and long sperm tails. In contrast, most of the other species have sperm with a broader lateral face and three ventral processes. These processes vary somewhat in size and shape, and in two Pogonomys and one Chiruromys species there is an extension of the nucleus into the most caudal of the three processes. Species of Anisomys and Hyomys have a sperm head with a broad lateral face but with only a single apical process. Abeomelomys sevia and Solomys salebrosus each have a distinct sperm head morphology unlike that of any other Australian murid; the latter species also has an extremely short sperm tail. Taxonomic and phylogenetic inferences are drawn from these data. Some of the phylogenetic conclusions are markedly divergent from traditional views, which are based on craniodental anatomy.

Three electrophoretically and morphologically distinct populations previously referred to Phalanger orientalis are recognised within Papua New Guinea and the Solomon Islands: Phalanger orientalis orientalis from northern Papua New Guinea and some nearby offshore islands, Phalanger orientalis breviceps from the Bismarck Archipelago and Solomon Islands, and Phalanger intercastellanus from eastern and southern Papua New Guinea and the islands of Milne Bay. P. o. orientalis is genetically and geographically relatively uniform. P. o. breviceps may have been introduced by humans over most of its range, and it is extremely variable, even within island populations. P. intercastellanus shows considerable intraspecific geographic variation, and is genetically divergent from P. o. orientalis (Nei's unbiased distance of 0.216) and P. o. breviceps (Nei's unbiased distance of 0.171). Indeed, this divergence is so marked that the previously recognised taxa Phalanger carmelitae and Phalanger vestitus are apparently genetically closer to P. orientalis than to P. intercastellanus.

Comparison among eight pseudocheirid species and two outgroup petaurids were made by means of the hydroxyapatite chromatography method of DNA hybridisation. Matrices of DELTAT(m) and DELTAT(m)H-C values were analysed with the FITCH algorithm in Felsenstein's PHYLIP (Version 3.3). Jackknifing and bootstrapping were applied to determine the stability of resulting topologies. All the phylogenetic analyses produced trees that support (1) the monophyly of the Pseudocheirus herbertensis complex, (2) the monophyly of Pseudocheirus, (3) a close relationship between Hemibelideus and Petauroides, and (4) a close relationship between Pseudochirops archeri and Pseudochirops cupreus. Rates of single-copy DNA evolution are slightly faster in Pseudocheirus, Hemibelideus, and Petauroides than in Pseudochirops. Hybridisation evidence also provides a framework for understanding the timing of the pseudocheirid radiation and suggests that the divergence between extant genera dates back to about 36 million years ago.

Resting metabolic rate (RMR) and evaporative water loss (EWL) were measured, and resistance (R) to evaporative water loss and water use index (WUI = EWL/RMR) were calculated, for 22 species of Western Australian gecko. For all available gecko data, body mass and temperature explained 85% of the variability in RMR (=14.5 mass0.833 100.0398 Ta µL h–1), and 70% of the variability in EWL (=0.126 mass0.539 100.049 Ta mg h–1 ). For Western Australian geckos, RMR and EWL were significantly influenced by body mass, using conventional regression and phylogenetic analyses. Resistance to evaporative water loss (R) was not significantly affected by body mass. Water use index was inversely related to body mass: WUI = 21.9 M–0.344 mg mL O2–1. There were significant differences between species for R and for standardised residuals of RMR, EWL and WUI. R was not correlated with phylogeny, and was significantly higher (P = 0.020) for saxicolous geckos (1467 s cm-1) than terrestrial geckos (797 s cm–1); arboreal geckos had an intermediate R (977 s cm–1). Species that ate termites had lower standardised linear regression residuals (P = 0.003) for RMR than did species that ate more general diets. Standardised residuals for EWL were almost significantly related to microhabitat (P = 0.053). Standardised residuals for WUI were significantly related to microhabitat (P = 0.016); saxicolous species had lower WUI than terrestrial species. Standardised linear regression residuals of the residuals from autoregression (which should be independent of both mass and phylogeny effects) still significantly correlated RMR and diet, but not EWL or WUI with microhabitat.

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