Bioluminescence

© 2016 Elsevier Ltd Kahle and Umbers introduce the ways by which organisms emit light though chemical reactions

The Effects of Residency and Body Size on Contest Initiation and Outcome in the Territorial Dragon, Ctenophorus decresii

Empirical studies of the determinants of contests have been attempting to unravel the complexity of animal contest behaviour for decades. This complexity requires that experiments incorporate multiple determinants into studies to tease apart their relative effects. In this study we examined the complex contest behaviour of the tawny dragon (Ctenophorus decresii), a territorial agamid lizard, with the specific aim of defining the factors that determine contest outcome. We manipulated the relative size and residency status of lizards in contests to weight their importance in determining contest outcome. We found that size, residency and initiating a fight were all important in determining outcomes of fights. We also tested whether residency or size was important in predicting the status of lizard that initiated a fight. We found that residency was the most important factor in predicting fight initiation. We discuss the effects of size and residency status in context of previous studies on contests in tawny dragons and other animals. Our study provides manipulative behavioural data in support of the overriding effects of residency on initiation fights and winning them.This study was funded by the Australian Research Council (www.arc.gov.au), the School of Botany and Zoology, and ANU (www.anu.edu.au). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript

The Institutions of Democracy

My dissertation is devoted to the question of which political decision-making institutions real-world democratic societies ought to adopt. Following a brief introduction in chapter one, it is structured around three sub-issues. Part one considers how citizens’ conduct in elections ought to be regulated. Chapter two offers a defence of compulsory voting, by appeal to the wrongness of free-riding, and responds to many of the objections raised by compulsory voting’s critics. Chapter three offers a defence of bans on vote buying. I show that recent arguments in favour of permitting vote buying are implausible. I then go on to criticise existing accounts of the wrongness of vote buying, and offer a novel, respect-based account of the wrongness of the practice. Part two considers whether, and how, persons conventionally excluded from the franchise ought to be included in the democratic process. Chapter four argues that the disenfranchisement of children is unjust. I argue that all major, plausible approaches to the justification of voting rights converge upon a requirement that children from around the age of twelve be enfranchised, and that none of the principal objections raised to child enfranchisement are persuasive. Chapter five considers the position of the cognitively disabled. I argue that, contrary to hopes expressed in the literature, enfranchising the cognitively disabled is unlikely to make any difference to the democratic processes’ under-responsiveness to such persons. Ensuring adequate consideration for the cognitively disabled will require deeper institutional reform. I consider a range of possibilities, ultimately arguing for the creation of a deliberative citizens’ assembly to address the issue. Part three, finally, considers whether the institutions presupposed in parts one and two – universal suffrage, and decision-making via the aggregation of citizens’ expressed preferences – can be justified in light of two significant challenges. Chapter six considers the competence objection, advanced by Jason Brennan. I show that Brennan’s objection is reliant upon a naïve account of citizens’ rights against risk-impositions, and cannot be sustained on any more plausible view. I also criticise Brennan’s preferred ‘epistocratic’ alternative to democracy. Finally, chapter seven considers the ‘lottocratic’ challenge. Several authors have recently argued that substituting universal suffrage and/or aggregative decision-making with some chance-based device would either preserve, or improve upon, the egalitarian appeal of democracy, while realising higher-quality results. I argue that the positive egalitarian case for lottocracy is implausible, and that the comparative egalitarian and instrumental merits of appropriately structured democratic arrangements will generally be superior

Genetic and environmental drivers of colour and pattern in the Australian jacky dragon (Amphibolurus muricatus)

The underlying drivers of variation in the colouration (colour and pattern) of animals can be genetic, non-genetic, or more likely, a combination of both. Understanding the role of heritable genetic elements, as well as non-genetic factors such as age, habitat or temperature, in shaping colouration can provide insight into the evolution and function of these traits, as well as the speed of response to changing environments. This project examined the genetic and non-genetic drivers of continuous variation in colouration in a lizard, the jacky dragon (Amphibolurus muricatus). We leveraged a large captive experiment that manipulated parental and offspring thermal environment to simultaneously estimate the genetic and non-genetic drivers of variation in colouration. We found that the overall brightness, the elongation of the longitudinal stripes on the dorsum and the contrast between light and dark patches of the pattern were all heritable. Colouration varied according to the age of the hatchling; however, the thermal environment of neither the parents nor offspring contributed significantly to colouration. It appears that developmental plasticity and maternal effects associated with temperature are not important drivers of variation in our measures of colouration

Phylogenetics of the skyhoppers (Kosciuscola) of the Australian Alps : evolutionary and conservation implications

The true biodiversity of Australia's alpine and subalpine endemics is unknown. Genetic studies to date have focused on sub-regions and restricted taxa, but even so, indicate deep divergences across small geographic scales and therefore that the bulk of biodiversity remains to be discovered. We aimed to study the phylogeography of the Australian Alps by focusing on the skyhoppers (Kosciuscola), a genus of five species of flightless grasshoppers whose combined distributions both span the region and are almost exclusively contained within it. Our sampling covered 650 km on the mainland and several sites in Tasmania with total of 260 specimens used to reconstruct a robust phylogeny of Koscisucola. Phylogenies were based on single nucleotide polymorphism data generated from double-digested restriction-associated DNA sequencing. Skyhoppers diverged around 2 million years ago and have since undergone complex diversification seemingly driven by climatic oscillations throughout the Pleistocene. We recovered not 5 but 14 clades indicating the presence of many unknown species. Our results support conspicuous geographic features as genetic breaks; e.g. the Murray Valley, and inconspicuous ones; e.g. between the Bogong High Plains and Mt Hotham. Climate change is progressing quickly in the region and its impact, particularly on snow, could have severe consequences for the skyhoppers' overwinter survival. The true diversity of skyhoppers highlights that biodiversity loss in the Alps as a result of climate change is likely to be far greater than what can be estimated based on current species numbers and that management including small geographical scales is key

Allelochemicals from 'Brassica' SPP. (Canola) Residues: Effects on Other Plants and Cereal Fungal Pathogens

'Brassica' spp. have been reported as showing allelopathic activity against other plants and fungi, with both living material and residues shown to be active. Glucosinolate breakdown products have been implicated in many of these allelopathic effects. Canola is a popular crop in Australia, with evidence of increased crop yields and freedom from fungal root diseases in cereals grown following canola. This supports canola's potential as an inhibitor of pathogens. It was hypothesised that allelopathic activity against other plants and fungi is due to compounds produced from canola residues, notably glucosinolate breakdown products. The experiments reported here supported the hypothesis that glucosinolate breakdown products can be phytotoxic to a number of indicator plant species. Indoleacetylnitrile (IAN), indoleacetylmethanol (IAM) and phenylethylamine (PEA) were shown to inhibit germination and early growth, with IAN being the most active. These compounds were found, using HPLC, to be present in canola residue leachates and their concentration estimated

Determining effects of areca (betel) nut chewing in a prospective cohort of pregnant women in Madang Province, Papua New Guinea

BACKGROUND: Chewing areca nut (AN), also known as betel nut, is common in Asia and the South Pacific and the habit has been linked to a number of serious health problems including oral cancer. Use of AN in pregnancy has been associated with a reduction in mean birthweight in some studies, but this association and the relationship between AN chewing and other adverse pregnancy outcomes remain poorly understood. METHODS: We assessed the impact of AN chewing on adverse outcomes including stillbirth, low birthweight (LBW, <2,500 g) and anaemia at delivery (haemoglobin <11.0 g/dL) in a longitudinal cohort of 2,700 pregnant women residing in rural lowland Papua New Guinea (PNG) from November 2009 until February 2013. Chewing habits and participant characteristics were evaluated at first antenatal visit and women were followed until delivery. RESULTS: 83.3% [2249/2700] of pregnant women used AN, and most chewed on a daily basis (86.2% [1939/2249]. Smoking and alcohol use was reported by 18.9% (511/2700) and 5.0% (135/2688) of women, respectively. AN use was not associated with pregnancy loss or congenital abnormalities amongst women with a known pregnancy outcome (n = 2215). Analysis of 1769 birthweights did not demonstrate an association between AN and LBW (chewers: 13.7% [200/1459] vs. non-chewers: 14.5% [45/310], P = 0.87) or reduced mean birthweight (2957 g vs. 2966 g; P = 0.76). Women using AN were more likely to be anaemic (haemoglobin <11 g/dL) at delivery (75.2% [998/1314] vs. 63.9% [182/285], adjusted odds ratio [95% CI]: 1.67 [1.27, 2.20], P < 0.001). Chewers more commonly had male babies than non-chewers (46.1% [670/1455] vs. 39.8% [123/309], P = 0.045). CONCLUSIONS: AN chewing may contribute to anaemia. Although not associated with other adverse pregnancy outcome in this cohort gestational AN use should be discouraged, given the potential adverse effects on haemoglobin and well-established long-term health risk including oral cancer. Future research evaluating the potential association of AN use and anaemia may be warranted. TRIAL REGISTRATION: ClinicalTrials.gov NCT01136850 (06 April 2010)

Risk factors and pregnancy outcomes associated with placental malaria in a prospective cohort of Papua New Guinean women

BACKGROUND: Plasmodium falciparum in pregnancy results in substantial poor health outcomes for both mother and child, particularly in young, primigravid mothers who are at greatest risk of placental malaria (PM) infection. Complications of PM include maternal anaemia, low birth weight and preterm delivery, which contribute to maternal and infant morbidity and mortality in coastal Papua New Guinea (PNG). METHODS: Placental biopsies were examined from 1451 pregnant women who were enrolled in a malaria prevention study at 14-26 weeks gestation. Clinical and demographic information were collected at first antenatal clinic visits and women were followed until delivery. Placental biopsies were collected and examined for PM using histology. The presence of infected erythrocytes and/or the malaria pigment in monocytes or fibrin was used to determine the type of placental infection. RESULTS: Of 1451 placentas examined, PM infection was detected in 269 (18.5%), of which 54 (3.7%) were acute, 55 (3.8%) chronic, and 160 (11.0%) were past infections. Risk factors for PM included residing in rural areas (adjusted odds ratio (AOR) 3.65, 95% CI 1.76-7.51; p </= 0.001), being primigravid (AOR 2.45, 95% CI 1.26-4.77; p = 0.008) and having symptomatic malaria during pregnancy (AOR 2.05, 95% CI 1.16-3.62; p = 0.013). After adjustment for covariates, compared to uninfected women, acute infections (AOR 1.97, 95% CI 0.98-3.95; p = 0.056) were associated with low birth weight babies, whereas chronic infections were associated with preterm delivery (AOR 3.92, 95% CI 1.64-9.38; p = 0.002) and anaemia (AOR 2.22, 95% CI 1.02-4.84; p = 0.045). CONCLUSIONS: Among pregnant PNG women receiving at least one dose of intermittent preventive treatment in pregnancy and using insecticide-treated bed nets, active PM infections were associated with adverse outcomes. Improved malaria prevention is required to optimize pregnancy outcomes