Song and female choice for extrapair copulations in the sedge warbler, Acrocephalus schoenobaenus

Although 90% of passerine birds live in socially monogamous pair bonds, molecular studies have revealed that genetic polygamy occurs in 86% of surveyed passerines, because individuals engage in copulations outside the pair bond (extrapair copulations; EPCs). Most explanations for the occurrence of EPCs involve female gaining indirect benefits from the extrapair male. The sedge warbler is a socially monogamous species in which some offspring result from EPCs (8% in this study). Complex song is a sexually selected male trait used by females which select mates based on a variety of male qualities. We used microsatellite DNA profiling to detect extrapair young and assign paternity. ‘Good genes’ theory predicts that females should engage in EPCs with males of higher quality than their social mate, with resulting fitness benefits. Extrapair males had smaller song repertoires and smaller territories than the social mate. This apparent preference for small-repertoire males as extrapair mates conflicts with the predictions from previous studies of this species. Sudden cessation of song after pairing may mean that song cues are unavailable for later extrapair matings and females may switch to other cues. Such behaviour may lead to different patterns of female choice during social and extrapair mating in the sedge warbler. We conclude that multiple reasons underlie patterns of female choice in this species.

Sexual selection and individual genetic diversity in a songbird

Here, we report for the first time, to our knowledge, a strong correlation between a measure of individual genetic diversity and song complexity, a sexually selected male trait in sedge warblers, Acrocephalus schoenobaenus. We also find that females prefer to mate with males who will maximize this diversity in individual progeny. The genetic diversity of each offspring is further increased by means of nonrandom fertilization, as we also show that the fertilizing sperm contains a haplotype more genetically distant to that of the egg than expected by chance. These findings suggest that species' mating preferences may be subject to fine tuning aimed at increasing offspring viability through increased genetic diversity. This includes external and internal mechanisms of selection, even within the ejaculate of a single male.

Color signals in the Black Grouse (Tetrao tetrix) : signal properties and their condition dependency

Recent progress in techniques of quantifying between‐individual differences of color‐based ornaments has revealed undiscovered possibilities for research in sexual selection. We present how the color spectra data can be comprehensively used for studying the importance of sexual ornaments in the black grouse and how these ornaments are related to a male condition. For this, we used both correlative field and experimental data. Field data indicated that older males had more chromatic coloration than yearlings. Blue chroma of males was correlated with male mating success. We experimentally manipulated yearling birds with testosterone implants and found that testosterone‐implanted males had impaired expression of several sexual ornaments: 10 months after the implantation, both structural‐based blue and carotenoid‐based red eye comb coloration were diminished, as well as lyre (tail) length. However, the manipulation did not affect vital traits under natural selection (wing length or body mass). Our data indicate that structural color is an important trait in sexual selection in this lekking species. Importantly, the data also indicate that male sexual ornaments are more susceptible to environmental conditions than the other male traits, thus showing their heightened condition dependency compared with the other traits mediating the honesty of signaling.

The implementation of chlamydia screening : a cross-sectional study in the South East of England

Background England's National Chlamydia Screening Programme (NCSP) provides opportunistic testing for under 25 year-olds in healthcare and non-healthcare settings. The authors aimed to explore relationships between coverage and positivity in relation to demographic characteristics or setting, in order to inform efficient and sustainable implementation of the NCSP.

Methods The authors analysed mapped NCSP testing data from the South East region of England between April 2006 and March 2007 inclusive to population characteristics. Coverage was estimated by sex, demographic characteristics and service characteristics, and variation in positivity by setting and population group.

Results Coverage in females was lower in the least deprived areas compared with the most deprived areas (OR 0.48; 95% CI 0.45 to 0.50). Testing rates were lower in 20–24-year-olds compared with 15–19-year-olds (OR 0.69; 95% CI 0.67 to 0.72 for females and OR 0.67; 95% CI 0.64 to 0.71 for males), but positivity was higher in older males.

Females were tested most often in healthcare services, which also identified the most positives. The greatest proportions of male tests were in university (27%) and military (19%) settings which only identified a total of 11% and 13% of total male positives respectively. More chlamydia-positive males were identified through healthcare services despite fewer numbers of tests.

Conclusions Testing of males focused on institutional settings where there is a low yield of positives, and limited capacity for expansion. By contrast, the testing of females, especially in urban environments, was mainly through established healthcare services. Future strategies should prioritise increasing male testing in healthcare settings.

Constructing a framework for building relationships and trust in project organisations : two case studies of building projects in China

A framework is constructed that can be used to foster trust and build relationships in construction project organizations in China. The research method was based on in-depth study of two building projects in China and data were collected via face-to-face interviews. The results show that as the project progresses, the dominant relationship within each stage deepens. The deepening relationship gives rise to different types of inherent risks such as a partner's self-interest seeking behaviour and opportunistic actions. To counterbalance these risks, trust fostering tools must be employed such as careful selection and effective management of partners. The framework for fostering trust and building relationship developed in the study suggests that (1) relationship deepens from shallow dependence to deep interdependence as the project progresses; (2) different relationships bring about distinct inherent risks; and (3) different trust-fostering tools counterbalance specific inherent risks. This framework could aid in reducing adversarial relationships by suggesting ways to foster trustworthy relationships.

Ultraviolet plumage colors predict mate preferences in starlings

Avian plumage has long been used to test theories of sexual selection, with humans assessing the colors, However, many birds see in the ultraviolet (<400 nm), to which humans are blind, Consequently, it is important to know whether natural variation in UV reflectance from plumage functions in sexual signaling, We show that female starlings rank males differently when UV wavelengths are present or absent, Principal component analysis of approximate to 1300 reflectance spectra (300-700 nm) taken from sexually dimorphic plumage regions of males predicted preference under the UV+ treatment. Under UV- conditions, females ranked males in a different and nonrandom order, but plumage reflectance in the human visible spectrum did not predict choice, Natural variation in UV reflectance is thus important in avian mate assessment, and the prevailing light environment can have profound effects on observed mating preferences.

Preferences for ultraviolet partners in the blue tit

The preference of female blue tits, Parus caeruleus, is correlated with the brightness of the ultraviolet (UV) crest; there is also assortative mating with respect to the crest's UV/violet chroma. However, manipulation of plumage reflectance is necessary to infer a direct causal link between UV plumage and mate choice. We gave both male and female blue tits a choice between a W-reflecting ('UV+') partner and a partner whose UV plumage reflectance had been removed ('UV-'). Male blue tits significantly preferred UV+ females. Similarly, female blue tits tended to prefer UV-reflecting males, but their UV+ preferences were nonsignificant. Neither sex showed a preference when conspecifics were replaced by a heterospecific. This study suggests mutual mate choice but male choice may be more strongly influenced by the visual appearance of potential mates. This is one of a few studies to show male mate preferences and the first demonstration of a direct relationship between UV reflectance and;male mate choice. (C) 1999 The Association for the Study of Animal Behaviour.

Dietary protein level interacts with ω-3 polyunsaturated fatty acid deficiency to induce hypertension

Background : Dietary ω-3 fatty acid deficiency can lead to hypertension in later life; however, hypertension is affected by numerous other dietary factors. We examined the effect of altering the dietary protein level on blood pressure in animals deficient or sufficient in ω-3 fatty acids.

Methods : Female rats were placed on one of four experimental diets 1 week prior to mating. Diets were either deficient (10% safflower oil; DEF) or sufficient (7% safflower oil, 3% flaxseed oil; SUF) in ω-3 fatty acids and contained 20 or 30% casein (DEF20, SUF20, DEF30, SUF30). Offspring were maintained on the maternal diet for the duration of the experiment. At 12, 18, 24, and 30 weeks, blood pressure was assessed by tail cuff plethysmography.

Results : At both 12 and 18 weeks of age, no differences in blood pressure were observed based on diet, however, by 24 weeks hypertension was evident in DEF30 animals; there were no blood pressure differences between the other groups. This hypertension in DEF30 group was increased at 30 weeks, with systolic, diastolic, and mean arterial pressure all elevated.

Conclusions : These results indicate that the hypertension previously attributed to ω-3 fatty acid deficiency is dependent on additional dietary factors, including protein content. Furthermore, this study is the first to plot the establishment of ω-3 fatty acid deficiency hypertension over time.

Ornament colour selection, visual contrast and the shape of colour preference functions in great bowerbirds, Chlamydera nuchalis

A male bowerbird visual signal includes his own plumage, a structure he  constructs out of plant material and coloured objects (ornaments) he places on or near the structure to make up the bower. Plumage and bower together are used to attract females for mating. Ornaments are known to contrast with plumage, bower structure and visual backgrounds in seven Australian bowerbird species (Endler et al. 2005, Evolution, 50, 1795-1818). We estimated the colour preferences in a wild population of great bowerbirds using artificially coloured objects widely spaced in bird colour space. We found that these birds prefer colours that contrast with their own plumage, the bower structure and the visual backgrounds adjacent to the bower, and that they have very strong dislikes for colours that are similar to their own plumage and to the visual backgrounds. The range of disliked colour hues was much narrower than the range of preferred hues, suggesting that the word 'preference' may be misleading. Preferences for colour are inherently multidimensional and should be studied in the context of their function.

Morphological signals of sex and status in spotted bowerbirds

The Spotted Bowerbird, Chlamydera maculata, appears to be sexually monomorphic. We caught and marked 118 birds in central Queensland, and sexed 88 using molecular methods. We found that our catch was strongly male-biased, both at bower sites and at non-bower feeding sites. We continued to observe the bird's behaviour after their release and so sub-divided males into sexual status groups as either bower-owners or non-owners. We searched for morphological measures, subjectively judged colour differences and quantitatively collected spectral measures of the visual properties of the crest feathers that would allow us to separate birds of differing sex and status. We found that bower owners had larger crests than non-owner males or females and that crest area provided the most accurate predictor of a bird's sex and status in a discriminant function analysis. We studied a cohort of seven males who went from non-owners to bower owners over three years, and found that their change in status was accompanied by a change in crest size – the only significant change in their morphology. Crest size did not relate to the mating success of a bower-owner. Instead, we suggest why the crest may differ between status groups and the implications that this may have for the sexual behaviour of male and female Spotted Bowerbirds.

Lived experience of gay men caring for others with HIV/AIDS : living, loving and dying in the era of HIV/AIDS

This thesis explored gay male carers’ experience of caring for their partner, brother or friend who had HIV/AIDS. Through using phenomenological methodology (van Manen, 1990), the day-to-day caring experiences were uncovered. The data gathered were then analysed through a nursing ‘lens’, with the concept of stigma as an anchoring point. The dual stigmas of homophobia and AIDS phobia impacted on the daily lives of these men as they cared for their loved one. The research identified six themes. These were: 1) the relationship; 2) coping with HIV and AIDS; 3) the corporal impact of HIV/AIDS; 4) experiences of carers including the absence of others; 5) living daily with the virus: Demands of people living with HIV/AIDS (PLWHA); and 6) saying goodbye, but wanting to keep the memory alive. The caring these men undertook, for which they were frequently unprepared, was intensive and complex, but because of their commitment and love they battled on. Because of a sense of shame associated with AIDS phobia on the part of the PLWHA, the carer often had to undertake this care in isolation, without support from family, friends or home health care agencies. The carers struggled with not only the demands of day-to-day care, but also with non-acceptance from family, both of the nature of the relationship with their partner and of their homosexuality. Family members were forced, often with great difficulty, to acknowledge the close commitment the men had to each other. Recognition that one had a terminal disease, HIV/AIDS was also required. The fear of potential transmission was high among carers, friends and family members. Notably, there was an absence of blame on the part of the carer towards his partner for contracting HIV/AIDS. The physical decline and marking of the body further stigmatised the PLWHA, which added to carers’ burdens. They endeavoured to minimise the physical decline in their partner, so he could continue to pass as healthy, and attempted to make the day-to-day living as normal as possible. The methods of combating weight loss and opportunistic infections meant frequent medical appointments, complex intensive medical procedures and help with personal care, which was undertaken at home largely without support from health care staff. Carers frequently struggled also with their partner’s denial of being ill. One strategy all carers used was to escape with their partners from their everyday life in Melbourne and attempt metaphorically to leave the HIV/AIDS behind; this was a time when they could rekindle their life together as it was before HIV/AIDS came into their lives. Some carers chose to holiday without their partner, to give themselves a break from the day-to-day caring, while others planned and took holidays with their partner. The decline of the health in the PLWHA meant that family members had to recognise and accept both the nature of the relationship and the presence of the disease. This recognition and acceptance often came only when the partner was very ill, even at the point of dying. Carers and their partners discussed the potential use of euthanasia, as a means of ending the final phase of life with some dignity. One carer and his partner used euthanasia, despite its illegal status. The main concern for all carers was providing comfort and a reduction in the pain associated with HIV/AIDS for the partner. The widespread grief associated with HIV/AIDS was evident amongst these carers. All had known other gay men who had died, some carers own partner had died, or was about to die. There was an overwhelming sense of grief, which at times was repressed as a means of coping day-to-day. All carers felt it was important and necessary to remember those lost to HIV/AIDS through the various public memorials, as they did not want their partner to be just another faceless person lost to this disease. This phenomenological study of carers’ experience highlights the need for health care workers to be aware of the differing strategies that gay men use to cope with HIV/AIDS. While it may seem that the carers are coping with care of their partner, the outer façade is not always an accurate portrayal of the true situation. Health care workers should enquire as to the assistance these carers need from health care services in order to continue to care for their loved one. Such assistance can be the simple recognition of the partner and acceptance of them as part of the PLWHA’s network; this inclusion and acceptance is half the battle.

Ecology of Pittosporum undulatum Vent. (Pittosporaceae) an environmental weed in south east Australia

Pittosporum undulatum Vent. (Sweet Pittosporum) is a densely foliaged tall shrub or small tree, native to the wet forests of south east Australia, This species now functions as a serious environmental weed in a range of habitats in Australia and on other continents and islands throughout the temperate, sub-tropical and tropical zones. This study investigated some of the ecological causes and consequences of P. undulatum invasion across a range of habitat types in south east Australia. Key aspects of P. undulatum biology and ecology investigated in the current study include; patterns of morphological variation across the range of habitats occupied (as a measure of the species’ plasticity), dispersal ecology and seed germinability, population structure and spatial pattern, community relationships and the ecological impacts of invasion. Phenotypic plasticity is considerable in P. undulatum. No clear patterns of geographic variation emerged from a study of leaf morphological attributes across the current range of this species on mainland south east Australia. The pattern of morphological variation is particularly complex in Victoria, where the invasion of this species is most advanced. The species’ adaptability to a range of environments and environmental conditions will likely promote further range expansion. The abundant winter fruit crop produced by functionally female P. undulatum plants attracts a suite of generalist opportunistic frugivores, which feed on P. undulatum fruits and seeds at various stages of fruit dehiscence, thereby enhancing dispersal opportunities for this species. P. undulatum seed collected from natural and invasive populations, at two stages of fruit maturity and from the scats and pellets of dispersal agents, displayed high germinability. European Blackbirds and Pied Currawongs are implicated as the main avian dispersal agents of P undulatum in south east Australia. The broader ecological implications of developing relationships between invasive fleshy-fruited bird-dispersed plant species and adaptive frugivores are likely to be considerable. The distribution of P. undulatutn seedlings was significantly negatively correlated with adult conspecifics and significantly positively correlated with trees and shrubs of other genera. This pattern reflects the importance of both firugivorous dispersal agents and the species’ germination and establishment requirements, in shaping the contagious distribution pattern typical of this species. These analyses suggest that recruitment opportunities for conspecific seedlings are limited beneath the canopy of adult conspecifics. Densities of P. undulatum were on average, 2.7 times higher in invaded populations, compared to the natural populations sampled. A male-bias was evident in all populations and no relationships between reproductive activity and the density of seedlings and juveniles were evident. Invading populations of P. undulatum impose substantial changes on ecosystem-level properties and functions. Mean species richness and cover-abundance declined notably once P. undulatum cover-abundance exceeded 20% at the invaded sites and 60% at the natural sites sampled. The natural communities sampled displayed comparatively greater resilience to the competitive effects of P. undulatum, but community attributes were affected at high densities and cover-abundance of this species. The cover-abundance of herbs and grasses declined most substantially with increasing P. undulatum at invaded sites, whereas, at the natural sites sampled, the species’ structural analogues appeared to be most affected by increasing P. undulatum cover-abundance. This study has demonstrated that the ecological consequences of P. undulatum population expansion are substantial and contribute to changes in the composition and successional trajectory of affected communities. These processes ultimately lead to the loss and simplification of biodiversity values and the homogenisation of affected habitats. P. undulatum has the potential to emerge as one of south east Australia's most serious environmental weed species.

Incorporating design explanation within formal object-oriented method (FOOM)

Requirements engineering is a commencing phase in the development of either software applications or information systems. It is concerned with understanding and specifying the customer's requirements of the system to be delivered. Throughout the literature, this is agreed to be one of the most crucial and, unfortunately, problematic phases in development. Despite the diversity of research directions, approaches and methods, the question of process understanding and management is still limited. Among contemporary approaches to the improvement of the current practice of Requirements Engineering, Formal Object-Oriented Method (FOOM) has been introduced as a new promising solution. The FOOM approach to requirements engineering is based on a synthesis of socio-organisational theory, the object-oriented approach, and mathematical formal specification. The entire FOOM specification process is evolutionary and involves a large volume of changes in requirements. During this process, requirements evolve through various forms of informal, semi-formal, and formal while maintaining a semantic link between these forms and, most importantly, conforming to the customer's requirements. A deep understanding of the complexity of the requirements model and its dynamics is critical in improving requirements engineering process management. This thesis investigates the benefits of documenting both the evolution of the requirements model and the rationale for that evolution. Design explanation explains and justifies the deliberations of, and decisions made during, the design activity. In this thesis, design explanation is used to describe the requirements engineering process in order to improve understandability of, and traceability within, the evolving requirements specification. The design explanation recorded during this research project is also useful in assisting the researcher in gaining insights into the creativity and opportunistic characteristics of the requirements engineering process. This thesis offers an interpretive investigation into incorporating design explanation within FOOM in order to extend and advantage the method. The researcher's interpretation and analysis of collected data highlight an insight-driven and opportunistic process rather than a strictly and systematically predefined one. In fact, the process was not smoothly evolutionary, but involved occasional 'crisis' points at which the model was reconceptualised, simplified and restructured. Therefore, contributions of the thesis lie not only in an effective incorporation of design explanation within FOOM, but also a deep understanding of the dynamic process of requirements engineering. The new understanding of the complexity of the requirements model and its dynamics suggests new directions for future research and forms a basis for a new approach to process management.

Aspects of the interaction between Xanthorrhoea australis and Phytophthora cinnamomi in south-western Victoria, Australia

Diseases in natural ecosystems are often assumed to be less severe than those observed in domestic cropping systems due to the extensive biodiversity exhibited in wild vegetation communities. In Australia, it is this natural biodiversity that is now under threat from Phytophthora cinnamomi. The soilborne Oomycete causes severe decline of native vegetation communities in south-western Victoria, Australia, disrupting the ecological balance of native forest and heathland communities. While the effect of disease caused by P. cinnamomi on native vegetation communities in Victoria has been extensively investigated, little work has focused on the Anglesea healthlands in south-western Victoria. Nothing is known about the population structure of P. cinnamomi at Anglesea. This project was divided into two main components to investigate fundamental issues affecting the management of P. cinnamomi in the Anglesea heathlands. The first component examined the phenotypic characteristics of P. cinnamomi isolates sampled from the population at Anglesea, and compared these with isolates from other regions in Victoria, and also from Western Australia. The second component of the project investigated the effect of the fungicide phosphonate on the host response following infection by P. cinnamomi. Following soil sampling in the Anglesea heathlands, a collection of P, cinnamomi isolates was established. Morphological and physiological traits of each isolate were examined. All isolates were found to be of the A2 mating type. Variation was demonstrated among isolates in the following characteristics: radial growth rate on various nutrient media, sporangial production, and sporangial dimensions. Oogonial dimensions did not differ significantly between isolates. Morphological and physiological variation was rarely dependant on isolate origin. To examine the genetic diversity among isolates and to determine whether phenotypic variation observed was genetically based, Random Amplified Polymorphic DNA (RAPD) analyses were conducted. No significant variation was observed among isolates based on an analysis of molecular variance (AMQVA). The results are discussed in relation to population biology, and the effect of genetic variation on population structure and population dynamics. X australis, an arborescent monocotyledon indigenous to Australia, is highly susceptible to infection by P. cinnamomi. It forms an important component of the heathland vegetation community, providing habitat for native flora and fauna, A cell suspension culture system was developed to investigate the effect of the fungicide phosphonate on the host-pathogen interaction between X. australis and P. cinnamomi. This allowed the interaction between the host and the pathogen to be examined at a cellular level. Subsequently, histological studies using X. australis seedlings were undertaken to support the cellular study. Observations in the cell culture system correlated well with those in the plant. The anatomical structure of X australis roots was examined to assist in the interpretation of results of histopathological studies. The infection of single cells and roots of X. australis, and the effect of phosphonate on the interaction are described. Phosphonate application prior to inoculation with P. cinnamomi reduced the infection of cells in culture and of cells in planta. In particular, phosphonate was found to stimulate the production of phenolic material in roots of X australis seedlings and in cells in suspension cultures. In phosphonate-treated roots of X australis seedlings, the deposition of electron dense material, possibly lignin or cellulose, was observed following infection with P. cinnamomi. It is proposed that this is a significant consequence of the stimulation of plant defence pathways by the fungicide. Results of the study are discussed in terms of the implications of the findings on management of the Anglesea heathlands in Victoria, taking into account variation in pathogen morphology, pathogenicity and genotype. The mode of action of phosphonate in the plant is discussed in relation to plant physiology and biochemistry.

Asexual reproduction does not produce clonal populations of the brooding coral Pocillopora damicornis on the Great Barrier Reef, Australia

We have investigated the relationship between genotypic diversity, the mode of production of brooded larvae and disturbance in a range of reef habitats, in order to resolve the disparity between the reproductive mode and population structure reported for the brooding coral Pocillopora damicornis. Within 14 sites across six habitats, the ratio of the observed (G o) to the expected (G e) genotypic diversity ranged from 69 to 100% of that expected for random mating. At three other sites in two habitats the G o /G e ranged from 35 to 53%. Two of these sites were recently bleached, suggesting that asexual recruitment may be favoured after disturbance. Nevertheless, our data suggest that brooded larvae, from each of five habitats surveyed, were asexually produced. While clonal recruitment may be important in disturbed habitats, the lack of clonality detected, both in this and earlier surveys of 40 other sites, implies that a disturbance is normally insufficient to explain this species’ continued investment in clonal reproduction.