Anatomy instruction at Australian and New Zealand medical schools has been the subject of considerable debate recently. Many commentators have lamented the gradual devaluation of anatomy as core knowledge in medical courses. To date, much of this debate has been speculative or anecdotal and lacking reliable supporting data. To provide a basis for better understanding and more informed discussion, this study analyses how anatomy is currently taught and assessed in Australian and New Zealand medical schools. A mailed questionnaire survey was sent to each of the 19 Australian and 2 New Zealand medical schools, examining the time allocation, content, delivery and assessment of anatomy for the 2008 academic year. Nineteen of the 21 (90.5%) universities invited to participate completed the survey. There was considerable variability in the time allocation, content, delivery and assessment of anatomy in Australasian medical schools. The average total hours of anatomy teaching for all courses was 171 h (SD ± 116.7, range 56/560). Historical data indicate a major decline in anatomy teaching hours within medical courses in Australia and New Zealand. Our results reveal that as there is no national curriculum for anatomy instruction, the curriculum content, instruction methodology and assessment is highly variable between individual institutions. Such variability in anatomy teaching and assessment raises an important question: is there also variable depth of understanding of anatomy between graduates of different medical courses?

Comparative phylogeography can reveal processes and historical events that shape the biodiversity of species and communities. As part of a comparative research program, the phylogeography of a new, endemic Australian genus and species of log-dependent (saproxylic) collembola was investigated using mitochondrial sequences, allozymes and anonymous single-copy nuclear markers. We found the genetic structure of the species corresponds with five a priori microbiogeographical regions, with population subdivision at various depths owing to palaeoclimatic influences. Closely related mtDNA haplotypes are codistributed within a single region or occur in adjacent regions, nuclear allele frequencies are more similar among more proximate populations, and interpopulation migration is rare. Based on mtDNA divergence, a late Miocene-late Pliocene coalescence is likely. The present-day distribution of genetic diversity seems to have been impacted by three major climatic events: Pliocene cooling and drying (2.5-7 million years before present, Mybp), early Pleistocene wet-dry oscillations (c. 1.2 Mybp) and the more recent glacial-interglacial cycles that have characterized the latter part of the Quaternary (<0.4 Mybp).

The neuroectoderm of the Euperipatoides kanangrensis embryo becomes distinguishable during germ band formation when the antennal segment is evident externally. During later stages of development, the neuroectoderm proliferates extensively and, at the anterior part of the head, newly-formed neuron precursor cells occupy most of the volume. The antenna forms from the dorsolateral side of the anterior somite. The antenna has no neuroectoderm of its own at the onset of its formation, but instead, neurons migrate out to the appendage from the nearby region of the developing brain. When the antennal tract is formed it is positioned horizontally in the brain, in line with the antennal commissure. Only later, and coincidentally with the anterior repositioning of the antenna, is the tract's distal part bent anteriorly and positioned laterally. The eye starts to develop posteriorly to the antenna and the antennal commissure. This suggests that the segment(s) associated with the onychophoran eye and antenna are not serially homologous with segments carrying equivalent structures within the Euarthropoda. Evidence is presented to further support the presence of a terminal mouth in the ground plan of the Onychophora and, hence, an acron may not exist in the arthropod clade.

As the putative sister group to the arthropods, onychophorans can provide insight into ancestral developmental mechanisms in the panarthropod clade. Here, we examine the expression during segmentation of orthologues of wingless (Wnt1) and engrailed, two genes that play a key role in defining segment boundaries in Drosophila and that appear to play a role in segmentation in many other arthropods. Both are expressed in segmentally reiterated stripes in all forming segments except the first (brain) segment, which only shows an engrailed stripe. Engrailed is expressed before segments are morphologically visible and is expressed in both mesoderm and ectoderm. Segmental wingless expression is not detectable until after mesodermal somites are clearly distinct. Early engrailed expression lies in and extends to both sides of the furrow that first demarcates segments in the ectoderm, but is largely restricted to the posterior part of somites. Wingless expression lies immediately anterior to engrailed expression, as it does in many arthropods, but there is no precise cellular boundary between the two expression domains analogous to the overt parasegment boundary seen in Drosophila. Engrailed stripes extend along the posterior part of each limb bud, including the antenna, while wingless is restricted to the distal tip of the limbs and the neurectoderm basal to the limbs.

Embryos of four ovoviviparous species of Australian onychophorans were examined to establish the process of their development, their reproductive cycle and to estimate the gestation period. The process of development is the same in all four species with, in the early embryo, segment halves separated by broad bands of extra-embryonic ectoderm and the embryos growing by the posterior addition of segments. Seven developmental stages (I-VII) can be clearly identified from external morphology. Analysis of the developmental stages of the embryos present in females collected throughout a calendar year has allowed estimation of the time taken for each developmental stage and demonstrated that there is an annual reproductive cycle with a total gestation period of c. 12 months. Stages I and VII are prolonged, the latter related to the late completion of midgut development. The simultaneous presence of stage I and stage VII embryos at certain times of year indicates an overlap of generations within the uteri, which is more extensive for some species than others. As the stage VII embryos of one cohort complete their development, enlarged oocytes are released from the ovaries to become fertilized as they pass the seminal receptacles and enter the uteri to start their embryonic development to form the next cohort. Cephalofovea clandestina, Phallocephale tallagandensis and Ruhbergia bifalcata have head structures in males, Euperipatoides rowelli does not. The presence of embryos at all times of year in the uteri of mature females has implications for mating and sperm storage that are discussed.

The reproductive biology of the ovoviviparous peripatus Euperipatoides rowelli was investigated from ®eld collections and laboratory cultures. The sexes have different demographics. The frequency distribution of individual weight is essentially L-shaped in females, but closer to normality for males: thus the sexes must exhibit different patterns of growth and/or mortality. Males are generally much smaller and rarer than females. The primary sex ratio seems to be 1:1 with equal investment in the sexes, while the tertiary ratio is highly female-biased. Logs with fewer individuals tend to be male-biased while well-populated logs tend to be female-biased. Males mature at 15±30% of the bodyweight of mature females. The weight frequency distribution of males without developed sperm in their tracts is strongly skewed to the lower weights, while that of males with sperm is more normally distributed, indicating that sperm production occurs as soon in life as possible. Males mature in their ®rst year of life, if growth rates in culture may be extrapolated to the wild. In contrast to this rapid maturity in males, females may mature as late as their second or third years. Most mature females, and many prior to maturity, carry sperm in their spermathecae. After maturity, there is an approximately linear relationship between body mass and number of developing embryos. Reproduction in E. rowelli is signi®cantly seasonal despite high individual variance, with a major bout of parturition in November±December (summer). A female can harbour one developed and one undeveloped batch of embryos in each uterus. Excesses of developed embryos in one uterus are counterbalanced by de®cits of undeveloped ones, indicating that females can use their paired reproductive tracts independently. Individual females in culture can experience episodes of parturition approx. 6 months apart without re-mating, thus gestation may be 6 months or more. Sperm in spermathecae remain capable of vigorous swimming for at least 9.5 months.

Comparative phylogeographic studies of animals with low mobility and/or high habitat specificity remain rare, yet such organisms may hold fine-grained palaeoecological signal. Comparisons of multiple, codistributed species can elucidate major historical events. As part of a multitaxon programme, mitochondrial cytochrome oxidase I (COI) variation was analysed in two species of terrestrial flatworm, Artioposthia lucasi and Caenoplana coerulea. We applied coalescent demographic estimators and nested clade analysis to examine responses to past, landscape-scale, cooling-drying events in a model system of montane forest (Tallaganda). Correspondence of haplotype groups in both species to previously proposed microbiogeographic regions indicates at least four refuges from cool, dry conditions. The region predicted to hold the highest quality refuges (the Eastern Slopes Region), is indicated to have been a long-term refuge in both species, but so are several other regions. Coalescent analyses suggest that populations of A. lucasi are declining, while C. coerulea is expanding, although stronger population substructure in the former could yield similar patterns in the data. The differences in spatial and temporal genetic variation in the two species could be explained by differences in ecological attributes: A. lucasi is predicted to have lower dispersal ability but may be better able to withstand cold conditions. Thus, different contemporary population dynamics may reflect different responses to recent (Holocene) climate warming. The two species show highly congruent patterns of catchment-based local genetic endemism with one another and with previously studied slime-mould grazing Collembola.

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