878 resultados para Mate Expulsion


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Female mate preferences are complex due to their greater selectivity in mates according to the good genes sexual selection theory. Additionally, research shows that female’s behaviors and mate preferences change cyclically due to the importance of attracting amate when conception risk is highest. However, research has not examined whether there is a relationship between menstrual cycle changes and mate expulsion (the casting off of a mate or ending a relationship). The present research examined whether fertility riskaffects mate expulsion decisions. Female participants completed a questionnaire which included demographic questions, such as information about the length and date of their menstrual cycle, mate expulsion scenarios, and a social desirability scale. Effects ofcurrent relationship status (a demographic measure) were also examined. If fertility risk does have an influence, the following patterns were hypothesized. High fertility women will be less likely to expel their mate due to an increased chance of conception and a need for access to parental investment resources from their mate. The results obtained indicate that fertility risks do not influence female’s decisions to expel their mates. Current relationship status in conjunction with fertility risk does affect mate expulsion. Thesefindings are discussed in terms of prior research and evolutionary theory.

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The specific mechanisms by which selective pressures affect individuals are often difficult to resolve. In tephritid fruit flies, males respond strongly and positively to certain plant derived chemicals. Sexual selection by female choice has been hypothesized as the mechanism driving this behaviour in certain species, as females preferentially mate with males that have fed on these chemicals. This hypothesis is, to date, based on studies of only very few species and its generality is largely untested. We tested the hypothesis on different spatial scales (small cage and seminatural field-cage) using the monophagous fruit fly, Bactrocera cacuminata. This species is known to respond to methyl eugenol (ME), a chemical found in many plant species and one upon which previous studies have focused. Contrary to expectation, no obvious female choice was apparent in selecting ME-fed males over unfed males as measured by the number of matings achieved over time, copulation duration, or time of copulation initiation. However, the number of matings achieved by ME-fed males was significantly greater than unfed males 16 and 32 days after exposure to ME in small cages (but not in a field-cage). This delayed advantage suggests that ME may not influence the pheromone system of B. cacuminata but may have other consequences, acting on some other fitness consequence (e.g., enhancement of physiology or survival) of male exposure to these chemicals. We discuss the ecological and evolutionary implications of our findings to explore alternate hypotheses to explain the patterns of response of dacine fruit flies to specific plant-derived chemicals.

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This paper introduces the special issue “China: Internationalizing the Creative Industries”, describing the Australian Research Council funded “MATE” project which provides the conceptual background for the questions the issue explores. The MATE project began with the expectation that as China evolves from its status as a developing country with an emphasis on primary industries and manufacturing, to a mature, market-driven economy benefiting from high levels of international investment, it will become more actively engaged with the global “knowledge economy” and “information society”. In this context, developments in the “creative industries”, which are playing such an important role in developed economies, might reasonably be expected in China. Although China continues to be characterised by strong central-policy settings, as the domestic consumer market matures there is greater scope for consumer-led creative business development. The “MATE” project aimed to capture some of these changes as they began to gain momentum across a range of services: Media, Advertising, Tourism and Education. This special issue continues this theme with papers that explore the theoretical challenges, economic questions and implications, and practical instantiations of creative industries growth in China. All papers contained in this special issue have been peer-reviewed.

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The issue of workplace bullying has received considerable attention in recent times in both the academic literature and in the print and electronic media. The stereotypical bullying scenario can be described as the “bully boss” model, where those in more senior positions tend to bully the staff they supervise. By way of contrast, this paper presents the findings of a three year exemplarian action research study into the lesser known phenomenon of workplace mobbing. Consistent with grounded theory methods, the findings are discussed in the context of emergent propositions in relation to the broader social, cultural, and organisational factors that can perpetuate workplace mobbing in the public sector.

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Occupational segregation is a major source of labour market rigidity and economic inefficiency due to a waste of human resources. Organisations are repeatedly recognised as gendered constructs exhibiting sustained work segregation, income and status inequality, as well as cultural and individual images of gender, and these are perpetuated through their processes, practices and pressures (Acker, 1990). A large percentage of Australia’s workforce is now employed in project-based or project-oriented organisations, leading to the claim that Australia is a project-based economy. For a continued strong performance in this economy, organisations that employ project personnel will need to consider how they address inclusivity and equality in diversity in project based temporary organisations to ensure the supply of high quality project professionals into the future. This paper investigates the inclusion processes experienced and exercised by men and women working in temporary organisations in project situations through a review of reports on the inclusion processes experienced by 60 project managers and project workers in three project based industries in Australia. Results indicate that temporary organisations are not implementing equality and diversity management strategies at the macro level and project workers are accepting this lack of recognition. However inclusivity and equality at the micro level of the team is seen as vital.

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Numerous efforts have been dedicated to the synthesis of large-volume methacrylate monoliths for large-scale biomolecules purification but most were obstructed by the enormous release of exotherms during preparation, thereby introducing structural heterogeneity in the monolith pore system. A significant radial temperature gradient develops along the monolith thickness, reaching a terminal temperature that supersedes the maximum temperature required for structurally homogenous monoliths preparation. The enormous heat build-up is perceived to encompass the heat associated with initiator decomposition and the heat released from free radical-monomer and monomer-monomer interactions. The heat resulting from the initiator decomposition was expelled along with some gaseous fumes before commencing polymerization in a gradual addition fashion. Characteristics of 80 mL monolith prepared using this technique was compared with that of a similar monolith synthesized in a bulk polymerization mode. An extra similarity in the radial temperature profiles was observed for the monolith synthesized via the heat expulsion technique. A maximum radial temperature gradient of only 4.3°C was recorded at the center and 2.1°C at the monolith peripheral for the combined heat expulsion and gradual addition technique. The comparable radial temperature distributions obtained birthed identical pore size distributions at different radial points along the monolith thickness.

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This report describes the Year Two/Campaign Two processes, and articulates findings from the major project components designed to address the challenges noted above (see Figure 1). Three major components comprise the Safe and Well Online project: 1) A participatory design (PD) process involving young people and sector partners (UWS) for; 2) campaign development (Zuni & Digital Arts Network); and 3) a cohort study (University of South Australia) to evaluate campaign effectiveness and attitude and behaviour change. Each sub-study comprehensively considered the ethical requirements of conducting online research with minors. The theoretical and methodological framework for measuring campaign engagement and efficacy (Sub-studies 3, 4 and 5) drew on the Model of Goal Directed Behaviour (MGB) (Perugini & Bagozzi 2001) and Nudge Theory (Thaler & Sunstein, 2008). This report extends the findings and conclusions of the Year One Pilot Study ‘‘Keep it Tame’’ (Spears et.al, 2015), and details the development and evaluation of the second of four Safe and Well Online Campaigns—‘‘Appreciate A Mate’: Helping others feel good about themselves’.

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This article addresses the need of an implementation mechanism for the protection of refugees’ rights. However, it is contended that the principle forms part of Customary International Law, under which it is binding on all states irrespective of whether or not they are parties to the Convention Relating to the Status of Refugees 1951 or its Protocol 1967. Since last decade, U.S and its allies have been fighting to curve terrorism which has raised many issues such as human rights violation, deportation, expulsion, extradition, rendition and many more. Pakistan has played a very critical role in War against Terrorism, particularly in reference of war in Afghanistan. Particular concern of this article is the violation of refugees’ rights in Pakistan in 2008 and 2010. This article would highlight the legislation regarding non-expulsion of Afghan refugees from Pakistan to a territory where they have well founded fear of persecution. Article is divided into three parts, the first one deals with “Principle of Non-Refoulement”, the second one deals with “exceptions to the principle” whereas the last one discusses the violation of the very principle in Pakistan with reference to Afghan refugees.

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The results presented in this thesis show that all females of a given population do not necessarily choose similar mating partners. Specifically, partner preferences of a fish, the sand goby (Pomatoschistus minutus), varied among individual females and depended on the social context at the time of choice. I also show that females assess multiple mate choice cues simultaneously; partner preferences were based more strongly on an interaction effect between different choice cues than on any individual cue. Furthermore, I found that preferred matings involved fitness benefits in the form of increased offspring success, but these benefits were not significantly affected by mate compatibility. Hence, mate choice for partner compatibility does not appear to be an important determinant of the observed variation in female mate preferences in this species. The context-dependency of female mating preferences revealed is relevant to how genetic variation in sexually selected traits might be maintained: as the mating success of a certain male type varies according to the choice context, directional sexual selection on male traits is shown to be less intense than generally thought making for a slower loss of genetic variation in these traits. Mating preferences of sand gobies were assessed by giving females a binary choice between males that differed in body size and/or other focus traits. These association preferences were found to be sexually motivated, repeatable and to correspond to actual mating decisions.

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We studied the mating behaviour of the primi-tively eusocial wasp Ropalidia marginata and the factors that may influence sperm transfer. By introducing a male and a female R. marginata into ventilated transparent plastic boxes, we were able to observe mating behaviour, and it involved mounting and short or long conjugation of the wasps. Dissection of female wasps after the observation indicated that long conjugation is a good behavioural predictor of sperm transfer. This finding makes it possible to obtain mated females without dissecting them every time. We tested the effect of age, season, relatedness, body size and female's ovarian status on mating. Under laboratory conditions, mating success declined rapidly below and above the ages 5-20 days. Within this age range mating success was significantly low in December compared to other months tested. There was no nestmate discrimination, and there was no influence of male and female body size or of the ovarian state of the female on the probability of sperm transfer.

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Males of several acoustically communicating orthopteran species form spatially and temporally structured choruses. We investigated whether male field crickets of the species Plebeiogryllus guttiventris formed choruses in the field. Males formed spatial aggregations and showed fidelity to a calling site within a night, forming stable choruses. Within aggregations, the acoustic ranges of males overlapped considerably. We tested whether males within hearing range of each other interacted acoustically. The chirps of simultaneously calling males were aphasic with respect to each other and showed no significant alternation or synchrony of calls. Some individuals changed temporal features of their calling songs such as chirp durations and chirp rates in response to a simultaneously calling neighbour. The implications of these results for female mate choice are discussed

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The intense interest in social Hymenoptera, on account of their elaborate sociality and the paradox of altruism, has often suffered from considerable gender imbalance. This is partly due to the fact that worker behaviour and altruism are restricted to the females and partly because males often live off the nest. Yet, understanding the males, especially in the context of mating biology is essential even for understanding the evolution of sociality. Mating patterns have a direct bearing on the levels of intra-colony genetic relatedness, which in turn, along with the associated costs and benefits of worker behaviour, are central to our understanding of the evolution of sociality. Although mating takes place away from the nest in natural colonies of the primitively eusocial wasp Ropalidia marginata, mating can be observed in the laboratory if a male and a female are placed in a transparent, aerated plastic container, and both wasps are in the range of 5-20 days of age. Here, we use this setup and show that males, but not females, mate serially with multiple partners. The multiple mating behaviour of the males is not surprising because in nature males have to mate with a number of females, only a few of whom will go on to lay eggs. The reluctance of R. marginata females to mate with multiple partners is consistent with the expectation of monogamy in primitively eusocial species with totipotent females, although the apparent discrepancy with a previous work with allozyme markers in natural colonies suggesting that females may sometimes mate with two or three different males remains to be resolved.

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Multi-species mating aggregations are crowded environments within which mate recognition must occur. Mating aggregations of fig wasps can consist of thousands of individuals of many species that attain sexual maturity simultaneously and mate in the same microenvironment, i.e, in syntopy, within the close confines of an enclosed globular inflorescence called a syconium - a system that has many signalling constraints such as darkness and crowding. All wasps develop within individual galled flowers. Since mating mostly occurs when females are still confined within their galls,, male wasps have the additional burden of detecting conspecific females that are ``hidden'' behind barriers consisting of gall walls. In Ficus racemosa, we investigated signals used by pollinating fig wasp males to differentiate conspecific females from females of other syntopic fig wasp species. Male Ceratosolen fusciceps could detect conspecific females using cues from galls containing females, empty galls, as well as cues from gall volatiles and gall surface hydrocarbons. In many figs, syconia are pollinated by single foundress wasps, leading to high levels of wasp inbreeding due to sibmating. In F. racemosa, as most syconia contain many foundresses, we expected male pollinators to prefer non-sib females to female siblings to reduce inbreeding. We used galls containing females from non-natal figs as a proxy for non-sibs and those from natal figs as a proxy for sibling females. We found that males preferred galls of female pollinators from natal figs. However, males were undecided when given a choice between galls containing non-pollinator females from natal syconia and pollinator females from non-natal syconia, suggesting olfactory imprinting by the natal syconial environment. (C) 2013 Elsevier Masson SAS. All rights reserved.