Polyzosteria cockroaches in Tasmania (Blattodea: Blattidae: Polyzosteriinae) represent a new, endemic species, with allopatric alpine and coastal sub-populations.

We describe the endemic Tasmanian cockroach, Polyzosteria yingina sp. nov. (Henry), 78 years after it was first documented. Evidence from morphology, biogeography and CO1 barcodes is used to distinguish this species from related mainland Australian taxa it has previously been confused with. Polyzosteria yingina sp. nov. has two strongly allopatric populations: a compact alpine population above 1000m and a dispersed east coastal one at sealevel. However, mitochondrial Control Region D-loop molecular analysis suggests a single species identity for these disparate populations. Detailed internal and external morphological descriptions and photographs of living and preserved type material are presented. We also speculate on some hypotheses which could account for the unusual distribution of this charismatic insect.

Large nested melanoma: a clinicopathological, morphometric and cytogenetic study of 12 cases.

A group of melanomas characterised by predominant growth as large nests within the epidermis has been described. These cases present a diagnostic challenge, as many traditional architectural criteria for the recognition of melanoma are absent. We report the clinical, histological, immunohistochemical, morphometric and cytogenetic features of a series of 12 cases of large nested melanoma. In this series, large nested melanoma accounted for 0.2% of cases of melanoma. The majority occurred on the trunk of middle aged patients with absent or minimal solar elastosis and 42% were associated with a component of benign intradermal melanocytic naevus, speaking to classification of these melanomas as falling within the spectrum of lesions developing in skin with low cumulative sun damage. In 67% of cases invasive melanoma was present. Criteria such as asymmetry, variation in nest size and intraepidermal nests with an underlying rim of junctional keratinocytes appear to be highly specific, and are strongly predictive of typical cytogenetic abnormalities of melanoma, which were identified in 92% of cases. Conversely, in addition to features which are definitionally absent or limited, features such as solar elastosis and cytological atypia do not appear to be particularly helpful in recognition of this variant.

Reprint of: The effectiveness of common thermo-regulatory behaviours in a cool temperate grasshopper.

Behavioural thermoregulation has the potential to alleviate the short-term impacts of climate change on some small ectotherms, without the need for changes to species distributions or genetic adaptation. We illustrate this by measuring the effect of behaviour in a cool temperate species of grasshopper (Phaulacridium vittatum) over a range of spatial and temporal scales in laboratory and natural field experiments. Microhabitat selection at the site scale was tested in free-ranging grasshoppers and related to changing thermal quality over a daily period. Artificial warming experiments were then used to measure the temperature at which common thermoregulatory behaviours are initiated and the subsequent reductions in body temperature. Behavioural means such as timing of activity, choice of substrates with optimum surface temperatures, shade seeking and postural adjustments (e.g. stilting, vertical orientation) were found to be highly effective at maintaining preferred body temperature. The maximum voluntarily tolerated temperature (MVT) was determined to be 44 °C ± 0.4 °C, indicating the upper bounds of thermal flexibility in this species. Behavioural thermoregulation effectively enables small ectotherms to regulate exposure to changing environmental temperatures and utilize the spatially and temporally heterogeneous environments they occupy. Species such as the wingless grasshopper, although adapted to cool temperate conditions, are likely to be well equipped to respond successfully to coarse scale climate change.

The effectiveness of common thermo-regulatory behaviours in a cool temperate grasshopper.

Behavioural thermoregulation has the potential to alleviate the short-term impacts of climate change on some small ectotherms, without the need for changes to species distributions or genetic adaptation. We illustrate this by measuring the effect of behaviour in a cool temperate species of grasshopper (Phaulacridium vittatum) over a range of spatial and temporal scales in laboratory and natural field experiments. Microhabitat selection at the site scale was tested in free-ranging grasshoppers and related to changing thermal quality over a daily period. Artificial warming experiments were then used to measure the temperature at which common thermoregulatory behaviours are initiated and the subsequent reductions in body temperature. Behavioural means such as timing of activity, choice of substrates with optimum surface temperatures, shade seeking and postural adjustments (e.g. stilting, vertical orientation) were found to be highly effective at maintaining preferred body temperature. The maximum voluntarily tolerated temperature (MVT) was determined to be 44°C±0.4°C, indicating the upper bounds of thermal flexibility in this species. Behavioural thermoregulation effectively enables small ectotherms to regulate exposure to changing environmental temperatures and utilize the spatially and temporally heterogeneous environments they occupy. Species such as the wingless grasshopper, although adapted to cool temperate conditions, are likely to be well equipped to respond successfully to coarse scale climate change.

Experimental manipulation of melanism demonstrates the plasticity of preferred temperature in an agricultural pest (Phaulacridium vittatum).

Phenotypic plasticity is a key trait of successful pest species, and may increase the ability to cope with higher, more variable temperatures under climate change. We investigate the plasticity of preferred temperature in a widespread agricultural pest, the wingless grasshopper (Phaulacridium vittatum). Preferred temperature is a measure of thermoregulatory behaviour through habitat selection. It is influenced by melanism, which affects body temperature by determining the amount of radiation absorbed by the body. First we demonstrate that body temperature and preferred temperature in P. vittatum is influenced by melanism, by comparing the preferred temperature of the colour morphs in laboratory thermal gradients and field body temperatures in natural populations. We then test whether preferred temperature changes in response to changes in body temperature, by determining preferred temperature before and after manipulation of melanism by painting. When melanism was manipulated experimentally in live grasshoppers, preferred temperature changed to reflect the thermal qualities of the new colour. The preferred temperature of light grasshoppers increased after they were painted black, and decreased after being painted white. Similarly, dark individuals that were painted white behaved like a light individual, maintaining a lower body temperature. Preferred temperature in P.vittatum is a plastic thermoregulatory response to ambient temperature, mediated by the influence of melanism on body temperature.

A test of the thermal melanism hypothesis in the wingless grasshopper Phaulacridium vittatum.

Altitudinal clines in melanism are generally assumed to reflect the fitness benefits resulting from thermal differences between colour morphs, yet differences in thermal quality are not always discernible. The intra-specific application of the thermal melanism hypothesis was tested in the wingless grasshopper Phaulacridium vittatum (Sjöstedt) (Orthoptera: Acrididae) first by measuring the thermal properties of the different colour morphs in the laboratory, and second by testing for differences in average reflectance and spectral characteristics of populations along 14 altitudinal gradients. Correlations between reflectance, body size, and climatic variables were also tested to investigate the underlying causes of clines in melanism. Melanism in P. vittatum represents a gradation in colour rather than distinct colour morphs, with reflectance ranging from 2.49 to 5.65%. In unstriped grasshoppers, darker morphs warmed more rapidly than lighter morphs and reached a higher maximum temperature (lower temperature excess). In contrast, significant differences in thermal quality were not found between the colour morphs of striped grasshoppers. In support of the thermal melanism hypothesis, grasshoppers were, on average, darker at higher altitudes, there were differences in the spectral properties of brightness and chroma between high and low altitudes, and temperature variables were significant influences on the average reflectance of female grasshoppers. However, altitudinal gradients do not represent predictable variation in temperature, and the relationship between melanism and altitude was not consistent across all gradients. Grasshoppers generally became darker at altitudes above 800 m a.s.l., but on several gradients reflectance declined with altitude and then increased at the highest altitude.

Correlations between physical and chemical defences in plants: tradeoffs, syndromes, or just many different ways to skin a herbivorous cat?

Most plant species have a range of traits that deter herbivores. However, understanding of how different defences are related to one another is surprisingly weak. Many authors argue that defence traits trade off against one another, while others argue that they form coordinated defence syndromes. We collected a dataset of unprecedented taxonomic and geographic scope (261 species spanning 80 families, from 75 sites across the globe) to investigate relationships among four chemical and six physical defences. Five of the 45 pairwise correlations between defence traits were significant and three of these were tradeoffs. The relationship between species' overall chemical and physical defence levels was marginally nonsignificant (P = 0.08), and remained nonsignificant after accounting for phylogeny, growth form and abundance. Neither categorical principal component analysis (PCA) nor hierarchical cluster analysis supported the idea that species displayed defence syndromes. Our results do not support arguments for tradeoffs or for coordinated defence syndromes. Rather, plants display a range of combinations of defence traits. We suggest this lack of consistent defence syndromes may be adaptive, resulting from selective pressure to deploy a different combination of defences to coexisting species.

Shifts in composition of monthly invertebrate assemblages in Moorland differed between lowland and montane locations but not fire-ages.

Understanding seasonal changes in invertebrate populations is important for understanding ecosystem processes and for conservation of invertebrate communities. Few studies have investigated variation in seasonal responses of multiorder and multispecies invertebrate assemblages. To determine whether temporal patterns in invertebrate assemblages and taxa vary between locations and vegetation age since burning, patterns of invertebrate occurrence were investigated monthly for 12 mo in cool temperate buttongrass moorlands at two locations (lowland and montane) containing paired plots with different fire history (young and old regrowth). For both locations and fire-ages, invertebrate taxon richness and abundance were generally higher during the warmer months than during the winter months. At the lowland location, foliage dwelling invertebrates were caught in greater numbers during winter than during summer owing to large numbers of Collembola. Each season had a distinct invertebrate assemblage. The invertebrate assemblages did not differ between young and old regrowth. The shifts in composition of monthly invertebrate assemblages between winter and summer differed between locations with assemblages in cooler months more dissimilar from warmer months at the montane location than the lowland location. Most taxa common to both locations had similar patterns of monthly occurrence but some taxa showed markedly different patterns. Mid- to late summer is the optimum time to conduct short-term surveys in buttongrass moorland to maximize species richness and abundance but short-term studies will miss significant components of the invertebrate community.

Putting plant resistance traits on the map: a test of the idea that plants are better defended at lower latitudes.

• It has long been believed that plant species from the tropics have higher levels of traits associated with resistance to herbivores than do species from higher latitudes. A meta-analysis recently showed that the published literature does not support this theory. However, the idea has never been tested using data gathered with consistent methods from a wide range of latitudes. • We quantified the relationship between latitude and a broad range of chemical and physical traits across 301 species from 75 sites world-wide. • Six putative resistance traits, including tannins, the concentration of lipids (an indicator of oils, waxes and resins), and leaf toughness were greater in high-latitude species. Six traits, including cyanide production and the presence of spines, were unrelated to latitude. Only ash content (an indicator of inorganic substances such as calcium oxalates and phytoliths) and the properties of species with delayed greening were higher in the tropics. • Our results do not support the hypothesis that tropical plants have higher levels of resistance traits than do plants from higher latitudes. If anything, plants have higher resistance toward the poles. The greater resistance traits of high-latitude species might be explained by the greater cost of losing a given amount of leaf tissue in low-productivity environments.

Classic metapopulations are rare among common beetle species from a naturally fragmented landscape.

1. The general importance of metacommunity and metapopulation theories is poorly understood because few studies have examined responses of the suite of species that occupy the same fragmented landscape. In this study, we examined the importance of spatial ecological theories using a large-scale, naturally fragmented landscape. 2. We measured the occurrence and abundance of 44 common beetle species in 31 natural rainforest fragments in Tasmania, Australia. We tested for an effect on beetle distribution of geographic variables (patch area, patch isolation and amount of surrounding habitat) and of environmental variables based on plant species, after first accounting for spatial autocorrelation using principal coordinates of neighbour matrices. The environmental variables described a productivity gradient and a post-fire succession from eucalypt-dominated forest to late-successional rainforest. 3. Few species had distributions consistent with a metapopulation. However, the amount of surrounding habitat and patch isolation influenced the occurrence or abundance of 30% of beetle species, implying that dispersal into or out of patches was an important process. 4. Three species showed a distribution that could arise by interactions with dominant competitors or predators with higher occurrence in small patches. 5. Environmental effects were more commonly observed than spatial effects. Twenty-three per cent of species showed evidence of habitat-driven, deterministic metapopulations. Furthermore, almost half of the species were influenced by the plant succession or productivity gradient, including effects at the within-patch, patch and regional scales. The beetle succession involved an increase in the frequency of many species, and the addition of new species, with little evidence of species turnover. Niche-related ecological theory such as the species-sorting metacommunity theory was therefore the most broadly applicable concept. 6. We conclude that classic and source-sink metapopulations are probably rare in this large-scale, naturally fragmented system, although dispersal processes like those occurring in metapopulations may have a substantial influence on community composition. However, deterministic processes (niche specialisation, species-sorting metacommunities and deterministic metapopulations) drive the occurrence or frequency of the majority of species. We urge further research into the prevalence of spatial ecological processes in large-scale natural ecosystems to expand our understanding of the processes that may be important in nature.

Waiting for the break of dawn? The effects of discharge time, discharge TISS scores and discharge facility on hospital mortality after intensive care.

OBJECTIVE: To assess the effects of discharge Therapeutic Intervention Scoring System (TISS) scores, discharge time and type of discharge facility on ultimate hospital mortality after intensive care. DESIGN: Retrospective cohort study. SETTING: General intensive care unit (ICU) in a district general hospital. PATIENTS AND PARTICIPANTS: One thousand six hundred fifty-four ICU patients discharged to hospital wards or high dependency units (HDUs). MAIN MEASUREMENTS AND RESULTS: Vital status at ultimate hospital discharge was the main outcome measurement. The crude hospital mortality after ICU discharge (12.6%) was significantly associated with increasing discharge TISS scores (chi(2) for trend =9.0, p=0.028). This trend was similarly observed after adjusting for severity of disease. Patients with high TISS scores (>30) who were discharged to hospital wards had a higher risk (1.31; CI: 1.02-1.83) of in-hospital death compared with patients discharged to HDUs. Crude mortality was significantly higher for late 20.00 h to 7.59 h) than for early (8.00 h to 19.59 h) discharges (18.8% versus 11.2%, chi(2) =12.1, p=0.0004). Adjusted for disease severity, the mortality risk was 1.70-fold (CI: 1.28-2.25) increased for late ICU discharges. Patients discharged late to hospital wards had significantly higher severity-adjusted risks (1.87; CI:1.36-2.56) than had patients discharged to HDUs (1.35; CI: 0.77-2.36). CONCLUSIONS: Both late discharge and high discharge TISS scores are indicators of "premature" ICU discharge and were associated with increased mortality. Intermediate care reduced the mortality of patients discharged "prematurely" from ICU. This adds to the growing evidence of the benefits of intermediate care after ICU discharge.