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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
71

Gendered expectations, personal choice, and social compatibility in Western Muslim marriages

Haqqani, Shehnaz 14 November 2013 (has links)
This study explores some major themes in relation to marriage among contemporary Western Muslims. These themes include gendered ideals and expectations of the potential spouse, generational differences, inter-religious marriages for Muslim women, and individual choice and parental authority in mate selection. It re-evaluates the Islamic notion of marital compatibility (kafa’a) and shows how this notion is understood and can be applied to contemporary Western Muslims. Due to little academic research on the problem particularly of unavailable spouses, the study relies primarily on blogs, online discussions of marriage among Muslims, and internet articles on Western Muslim marriages. The dilemma faced by Western Muslims, particularly females, is that there is a lack of compatible available husbands for them. The study finds that, according to marriage-minded women, this unavailability is largely due to traditional expectations of gender roles from potential husbands contrasted against the women’s unconventionally older ages, focus on education and career, and overall understanding of power dynamics in marriage. The study also explores changing methods of mate selection among Western Muslims, which include services offered by Islamic centers, Internet matchmaking, and marriage events—where the average male participant is younger than the average female participant. As the age of marriage-minded females increases, their individual choice is more recognized in their marriage while their options of suitable men decreases significantly. Many of them therefore turn to interfaith marriages, which are not recognized by Islamic law, although some religious authorities across the West them on the basis of necessity. Western Muslim women are in a unique but complicated space where they are struggling to maintain their personal ideals of education and careers and are seeking partners who share these ideals; yet, with the tension between men’s expectations of women and women’s of men during courtship, and the role of family in mate selection, the problem of marriage becomes more complex with the various axes contributing to it. / text
72

The cognitive biology of mate choice in túngara frogs (Physalaemus pustulosus)

Akre, Karin Lise 01 August 2011 (has links)
Sexual selection is responsible for a great diversity of elaborate male traits. A general female preference for males that have exaggerated traits drives this process, but the reasons females exhibit this preference are often unclear. Recent advances in understanding signal evolution have emerged from studies of receiver psychology that focus on how receivers perceive and process communication signals. I apply the perspective of receiver psychology to understand female preference for elaborate signals in túngara frogs (Physalaemus pustulosus). Male túngara frogs produce advertisement calls of variable complexity. Females exhibit a strong preference for complex to simple calls, but previous studies have not found consistent patterns of preference between calls of variable complexity. In my doctoral research, I investigate the function of variable complexity in túngara frogs. Specifically, I address the following questions: 1) Are calls of variable complexity especially relevant to females in certain contexts? Do males respond to female behavior by increasing their production of complex calls? 2) Does male to female proximity influence female response to call complexity? 3) Are females constrained by their perceptual biology in discriminating differences in call complexity? 4) Can females remember attractive males over silences between bouts of advertising? Is working memory for attractive males dependent upon signal complexity? And 5) Does signal memorability increase with signal complexity in a linear relationship? These studies provide several new perspectives to an understanding of female preference for elaborate signals. Phonotaxis experiments demonstrate that females use elicitation behaviors to influence male production of complex calls, that proximity influences female response to signal elaboration, that females are constrained by their perceptual biology in discriminating between complex calls, that memory can influence the evolution of signal complexity, and that memorability and signal complexity share a non-linear relationship. / text
73

Gender differences regarding the idealized sex partner

McGuirl, Kerry Elizabeth January 1998 (has links)
College student men (n = 185) and women (n = 244) rated how desirable certain characteristics are in an ideal sex partner within a long-term relationship. They reported personal beliefs and predictions about the other gender's preferences. Of the twenty-six items that comprised each measure, factor analyses yielded five subscales: Communication/Openness, Physical Attractiveness, Knowledge/Skill, Take Control, and Response/Drive. As hypothesized, men placed greater emphasis than did women on Physical Attractiveness and Response/Drive, whereas women, more than men, believed Knowledge/Skill was important. Men and women differed completely on what they thought was important to each other. Furthermore, men recognized that there were gender differences on all subscales but Knowledge/Skill, whereas women recognized gender differences on all subscales. When the actual responses of men and women were compared with the beliefs that each had about the other, results showed that both genders underestimated the importance the other placed on Communication/Openness and overestimated that of Physical Attractiveness. Results are discussed with regard to implications for counselors. / Department of Psychological Science
74

晚婚女性公務員婚姻觀與擇偶偏好之研究 / A study of marital values and mate-selection preferences of female civil servants who get married late

吳如茵, Wu,ju ying Unknown Date (has links)
近年,臺灣社會晚婚人口急速攀升,導致單身人口增加,進而造成了生育少子化、人口高齡化等人口結構面的影響外,在其他政治、經濟、社會、勞動力等各方面,也衍生不同程度的問題,晚婚現象不只是男女兩性的問題。因此,此課題值得深究。本研究旨在探究晚婚、未婚及單身等現象是否亦反映在收入穩定的女性公務員上,期望藉由窺探晚婚女性公務員婚姻觀及擇偶偏好之樣貌,企圖瞭解真正形成晚婚的深層因素,並提供許多晚婚女性公務員,做為對自我認識之參考。 本研究採質性研究之深度訪談法。研究對象總數共計10人,均為30歲(含)以上迄今仍未曾有過法律婚約關係及婚姻經驗、且現仍服務於政府各機關之女性公務員。經分析訪談資料後,所得研究發現綜述如下: 一、對婚姻的必要性多抱持正面看法,普遍認為晚婚是一種趨勢,表示35歲以 後才算晚婚,並抱持著隨緣等待的消極態度。而30歲代表著步入人生另一 個階段,對未來的不確定感也會因此加深。 二、期望中的理想婚姻樣貌係夫妻共組小家庭、經濟無虞,彼此是對等、分享 的關係。在家務分擔上各自負責擅長部分,並能視實際工作狀況相互協 調。 三、生活圈狹隘及已逾適婚年齡為目前最主要遭遇的擇偶困境。此外,對性有 高度自主性,普遍能接受與男友有婚前性行為。 四、交往經驗中對方家人的態度及預期婚後與公婆相處的壓力,都是主要考量 是否進ㄧ步交往或步入婚姻的要素。 五、晚婚女性公務員在選擇其婚配對象時,最看重心靈層面的情感條件,在意 雙方的溝通狀況及親密感。 本研究根據研究發現,提出以下建議: 一、建議晚婚女性公務員應積極參與活動,培養個人興趣,拓展生活及增廣自 身見聞,主動發展話題。並應建立正向信念,親友經驗做為參考之用。 二、釐清自我需求,設定適合、務實的擇偶條件,及早規劃人生道路、積極拓 展人際。 三、應建立正確的婚姻教育及觀念,重新確立婚姻的意義及重要性,培養獨立 自主的生活能力及擔當精神。 四、建議機關單位可多舉辦跨機關、跨科室之聯誼活動,提供多元交友管道, 拓展認識異性之機會。 / In recent years, the number of people getting married late in Taiwan has been rising rapidly. It leads to the increases of single people, which results in further demographic structure changes such as fewer newborns and aging populations. It also causes different problems in other social aspects such as politics, economy, society and labor force. The phenomenon of people getting married late isn’t just a gender problem. Therefore, this subject is worthy of inquiry. This study is about investigating if the phenomenon of people getting married late and single makes an impact on the female civil servants, who have steady incomes. In this study, I try to understand the profound reasons that cause female civil servants to get married late by observing their marital values and mate-selection preferences. This study will serve as a reference to them that might help them to understand themselves better. This study is conducted in a qualitative research methodology through in-depth interviews with 10 female civil servants, who are over 30-year-old and never have marriage relationships. After analyzing their interview data, this study finds as blew: 1. They all feel positive about the necessity of marriage. However, they also think that it’s a trend to get married late, which is over 35-year-old. And they keep passive attitudes toward marriage. Being 30-year-old means step into another stage of life to them, and it will deepen the feeling of uncertainty for the future. 2. The ideal marriage is a nuclear family. The couple are financially free, and having an equal and sharing relationship. They share household chores which coordinate with their works. 3. Narrowness of life circle and being over marriageable age are the main obstacles for them to find partners. In addition, they value sexual autonomy and premarital sex is acceptable to most of them. 4. The attitude of their partner’s family members and the foreseeable pressure of getting along with their parents-in-law after getting married are the main considerations whether they should have a relationship or get married. 5. When it comes to mate-selection, the emotional aspect is the most important condition for those female civil servants who get married late. They care about how they communicate with their mates and the close feeling between them. Based on this study, I made several recommendations as below: 1. For female civil servants who get married late, I suggest that they should be more positive in activities, expand their life and experiences and find conversation topics actively. Establish positive faith and learn from the experiences of relatives and friends. 2. Define their own needs and pragmatic conditions for their future partners.Make a plan for life earlier and expand interpersonal relationships actively. 3. Establish correct ideas about marriage. Re-establish the meaning and importance of marriage. And cultivate an independent life ability and responsible attitude. 4. I recommend the government agencies to hold more gatherings cross organizations and offices. They will provide civil servants multi-dimensional channels to make friends and expand opportunities to know friends of opposite sex.
75

Romantic relationships developed by international students at some colleges and universities in Hawaiʻi

Minami, Aki January 2004 (has links)
Thesis (M.A.)--University of Hawaii at Manoa, 2004. / Includes bibliographical references (leaves 208-219). / xiii, 219 leaves, bound ill. 29 cm
76

Parasitismo em Cnemidophorus ocellifer (Squamata:Teiidae) de quatro ecossistemas do nordeste brasileiro

Eloi, Felipe Jardelino 30 April 2013 (has links)
Made available in DSpace on 2015-04-17T14:55:28Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 1250638 bytes, checksum: d83f38db8255b998ec13aaf8ad13c20b (MD5) Previous issue date: 2013-04-30 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Parasite is an organism that lives inside (endo) or in surface (ectoparasites) from another organism, the host, feeding, showing some degree of adaptation and causing some damage to it. In Brazil one of the most commonly found lizard is the Cnemidophorus ocellifer, active forager, with wide national distribution except Amazon, and diurnal heliotherms, which mainly inhabits open areas. Therefore, this study aims to characterize the patterns of infestation by parasites in populations of C. ocellifer in four ecoregions of northeastern Brazil, the abundance, composition, diversity and body distribution. We examined 399 specimens of C. ocellifer. Eutrombicula alfreddugesi was the only ectoparasite species found in all populations studied. The Sete Cidades population was the most parasitized with 9,819 mites found, and the population of Barra Cunhaú was less parasitized, with only 445 individuals and 66 mites free from ectoparasites. We found six types of endoparasites: Platyhelminths Cestoda (n=49) and Nemathelminths Pharyngodon sp. (n=1633) in stomachs and intestines, Nemathelminths Piratuba sp. (n=6), Oswaldofilaria sp. (n=17) and Physaloptera spp. (n=1), only in coelomic cavities in Sete Cidades, and Pentastomid Raillietiella mottae (n=5) in the lungs only in Barra do Cunhaú. For ectoparasites males are significantly more infested than females and this is probably linked to the inverse relationship that exists between testosterone levels in the blood and immune system efficiency. The sites of infestation were instrumental in the infestation by ectoparasites in all populations studied, indicating mainly post-inguinal regions as significantly more infested sites in all populations. These results are not only related to the presence of dermal folds in these regions, since there are folds in other parts of the body of these lizards and they showed no such significant results. The infestation was also partially influenced by the environment, but it may be that this is influenced by secondary factors and not necessarily environmental. Body condition, another fitness parameter, was also partially influenced by parasitic infestation, but not as expected, where most infected individuals have better body condition, refuting the hypothesis (individuals with greater intensity would be less parasitic body condition score). An overview of all these results suggests that the infestation by ectoparasites can be associated with characteristics of fitness and sexual selection, corroborating the Handicap Theory. If not this way, a parasite can present with its host, a neutral relationship (comensal) or even positive, even at low level (mutual). Endoparasites may be acting illegitimate way, without the hosts in no way benefit from this interaction, but can at least present a pattern of species diversity known for other taxa. / Parasita é um organismo que vive dentro (endoparasitas) ou na superfície (ectoparasitas) de outro organismo, o hospedeiro, se alimentando, apresentando certo grau de adaptação e causando algum dano ao mesmo. No Brasil um dos lagartos mais comumente encontradas é Cnemidophorus ocellifer, forrageador ativo, de ampla distribuição nacional exceto Amazônia, heliófilo e diurno, que habita principalmente áreas abertas. Sendo assim, o presente estudo tem como objetivo caracterizar e testar hipóteses sobre os padrões de infestação por parasitas em populações de C. ocellifer de quatro ecorregiões do Nordeste Brasileiro, quanto à abundância, composição, diversidade e distribuição corporal, bem como sobre os efeitos da intensidade parasitária sobre a aptidão dos hospedeiros. Foram examinados 399 exemplares de C. ocellifer de quatro populações: Barra do Cunhaú/RN, Cabaceiras/PB, PARNA Sete Cidades/PI e REBIO Guaribas/PB. Eutrombicula alfreddugesi foi a única espécie de ectoparasita encontrada em todas as populações estudadas. A população de Sete Cidades/PI foi a mais parasitada, com 9.819 ácaros encontrados, e a população de Barra do Cunhaú/RN foi a menos parasitada, com apenas 445 ácaros e 66 indivíduos livres de ectoparasitas. Foram encontrados seis tipos de endoparasitas: Platelmintos Cestoda (n=49) e Nematelmintos Pharyngodon sp. (n=1.633), em estômagos e intestinos; Nematelmintos Piratuba sp. (n=6), Oswaldofilaria sp. (n=17) e Physaloptera sp. (n=1), em cavidades celomáticas (apenas em Sete Cidades); e o Pentastomídeo Raillietiella mottae (n=5) nos pulmões dos indivíduos de Barra do Cunhaú. Para ectoparasitas os machos são significativamente mais infestados que fêmeas e isso provavelmente está ligado à relação inversamente proporcional que existe entre as taxas de testosterona no sangue e a eficiência do sistema imune. Os sítios de infestação foram determinantes para a infestação por ectoparasitas em todas as populações estudadas, indicando principalmente as regiões pósinguinais como os sítios significativamente mais infestado em todas as populações. Esses resultados não estão relacionados apenas a presença de dobras dérmicas nessas regiões, já que existem dobras em outras partes do corpo desses lagartos e elas não apresentaram, significativamente, altas infestações. A infestação também foi parcialmente influenciada pelo ambiente, mas pode ser que essa influência seja por fatores secundários e não necessariamente ambientais. A condição corporal, outro parâmetro de aptidão, também foi parcialmente influenciada pela infestação parasitária, mas não como esperado, onde indivíduos mais parasitados apresentaram melhor condição corporal, refutando a hipótese mencionada na introdução (indivíduos com maior intensidade parasitária teriam menor índice de condição corporal). Um apanhado geral de todos esses resultados sugere que a infestação por ectoparasitas pode estar associada a características de aptidão e seleção sexual, corroborando a Teoria da Desvantagem. Se não dessa forma, um parasita pode apresentar, com seu hospedeiro, uma relação neutra (comensalista) ou até mesmo positiva, mesmo que em baixo nível (mutualista). Os endoparasitas podem estar atuando de forma espúria, sem que os hospedeiros em nada se beneficiem com essa interação, mas podem ao menos apresentar um padrão de diversidade de espécies conhecido para outros táxons.
77

For Richer or For Poorer: How Financial Resources Affect Women’s Mate-Value

Fisher, Alexandra 04 January 2016 (has links)
Research on mate preferences suggests that men value physical attractiveness and youthfulness most in potential partners, whereas women value status and resources most in a potential partner (Buss, 1989). These differences in mate preferences have implications for the value men and women place on these characteristics (e.g. attractiveness and resources) in potential mates. A man’s attractiveness and financial resources both contribute positively to his mate-value, (Sprecher, 1989; Townsend & Levy, 1990). A woman’s attractiveness also contributes to her mate-value (Sprecher, 1989; Townsend & Levy, 1990), but the value of her resources is less clear. I expected that men’s evaluation of a woman’s financial resources would be dependent on her level of attractiveness. I hypothesized that a woman’s financial resources would add to her mate-value when she was highly attractive, but detract from her mate-value when she was typically attractive. In Study 1, a woman of varying attractiveness (typical vs. high) approached men on campus and delivered a speech that conveyed her future income (low vs. high). Men’s reported desire to join her focus group was used as measure of their impressions of her mate-value. Study 2 directly assesses participant’s romantic interest in targets of varying income (low vs. high) and attractiveness (typical vs. high) using a controlled laboratory method where both men and women evaluated a profile of a potential romantic partner. The results of both studies supported my hypotheses. This research provides insight into the complicated nature of a woman’s financial resources as part of her overall mate-value. / Graduate / 2019-06-30
78

金融人員婚姻觀與晚婚因素一以F銀行為例 / Financial People's Outlook on Marriage and Factors Leading To Their Late Marriage:As Exemplified by F Bank

陳珮瑜 Unknown Date (has links)
晚婚人口的增加,影響所及最顯著的就是生育率的降低。所以晚婚現象不單單只是男女兩性的問題,也衍生出人口結構面及政府社會福利與相關政策制定等的問題。而晚婚現象也充斥著各行各業,以國內金融業為例,金融業的員工往往以女性為大宗,而在男性寥寥可數的工作環境下,容易造成金融業女性想要內銷不易;再加上工作時間過長、工作壓力大,不容易自然認識到異性,若又不積極向外打開社交圈,單身的狀態更是難以突破,因此為一項值得深究的課題。 本研究採取質化研究的半結構式訪談法,訪問了12名已達30歲(含)以上而尚處於未婚狀態的女性金融從業人員,旨在探究晚婚女性金融人員的擇偶條件與婚姻態度,企圖統整出影響她們晚婚的因素。經分析訪談資料後,所得研究重要發現如下述: 一、結婚之必要性鬆動。婚姻是一種緣分,而結婚最重要的前提就是是否能尋得一位「值得託付終身的對象」,如果結婚沒有單身好,那麼就更沒有結婚的必要了! 反而認為女孩子經濟獨立比較重要。 二、不一定只有結婚才算是盡子女的責任,不婚有時反而有更多的時間可以陪伴家人,進而孝順自己的父母親,為自己的原生家庭盡一份力量,讓父母們能夠放寬心,也是另一種盡子女的責任,而且長輩也不希望子女是為了結婚而結婚。 三、結婚也不一定要生小孩。生不生小孩應該是要在夫妻雙方都有穩定的經濟基礎及規劃下,再來慎重考慮之後做決定,此也正可呼應為何現在我國的生育率如此低落。 四、不婚不等於晚年會孤獨。人本來就是孤獨的,有時候結婚有伴也不見得就比較不孤獨,況且可以排解孤獨的方式也有很多種,每個人都會變老,最重要的應該是要培養出自己的興趣。 五、工作環境、壓力多多少少對晚婚都有點影響。尤其是現今金融業面對國際化以及同行競爭,處在此種競爭激烈的工作環境下,工作壓力大、工時長,往往下班時就已經疲累到不行,假日時間可能又必須得準備證照考試來努力充實自己,有時忙到可能都沒有時間找對象,或者好好去經營一段感情,也會擔心有了家庭小孩後,該如何在工作跟家庭間做一個權衡。 六、而這些晚婚女性金融人員仍未結婚最主要的原因還是尚未找到一位「值得託付終身的對象」,在未找到合適的人之前,採取不要勉強自己,寧缺勿濫的態度。而且年紀越大,經歷過的事情越多,越能夠瞭解婚姻的現實面,對於結婚也就越沒有了衝動。 本研究並根據研究發現,提出以下建議: 一、如果有結婚的意願及打算,就應該要積極準備,拓展人際關係,不要為自己設限,能夠多元交友,不要再只是消極的隨緣等候緣分的到來。 二、釐清自己真正的需求,設定務實、適合自己的擇偶條件,而非執著於某些三高等的外在條件。 三、建議相關單位可多舉辦聯誼活動,提供多元交友管道,拓展認識異性之機會。 / The number of people getting married late has been increasing, and the most significant impact is the reduction in fertility. The phenomenon of people getting married late isn’t just a gender problem, but also causes different problems in demographic structure and government social welfare policy. And the phenomenon of late marriage filled various walks of life, for example in the domestic financial industry many of its employees are women but few men. Its long working hours and pressure cause women more difficult to find their ideal person. Therefore, this subject is worthy of inquiry. This study uses the qualitative methodology of semi structured interviews, to interview twelve female financial people who are over 30-year-old and unmarried. In this study I try to integrate the reasons that cause female financial people to get married late by observing their mate-selection preferences and marital values. After analyzing their interview data, the results of the research show the following key points: 1.The most important prerequisite to get married is to find an ideal person. If getting married is not better than single, then the marriage is no more necessary! 2.Marriage is not only being regarded as filial piety anymore. Unmarried people can have more time to accompany with their family and their elders hope their children do not marry just to marry. 3.Getting married doesn’t have to have children. A decision to having children should be at a stable economic base and after careful consideration. This is also why our fertility rate is so low. 4.Not married doesn’t mean you will be lonely when you are old. Everyone will get older, the most important thing is you should cultivate your own interests. 5.Working environment and pressure have little influence on the late marriage. Especially the financial sector now faces the international competition. Such a competitive environment, work pressure, and long working hours make them not have time to find their ideal person or to manage a relationship. 6.And the main reason that female financial people getting married late is not found an ideal person and they don’t want to force themselves. This study also offers the following suggestions: 1.Make a plan for life earlier and expand interpersonal relationships actively. Don’t set limits for yourself and keep passive attitudes toward marriage. 2.Define their own needs and pragmatic conditions for their future partners. 3.I recommend the coherent units to hold more gatherings cross organizations. Provide civil servants multi-dimensional channels to make friends and expand opportunities to know friends of opposite sex.
79

The Genetic and Social Mating System of a White-Backed Population of the Australian Magpie (Gymnorhina tibicen tyrannica)

Durrant, Kate, n/a January 2004 (has links)
The Australian magpie (Gymnorhina tibicen) is a large, sedentary, omnivorous passerine. In some populations, individuals live in groups, and some of these groups breed cooperatively. The white-backed magpie (G. t. tyrannica) from the south-eastern corner of the continent, has had relatively little study, and few details are known of its mating system, social structure, and method of parental care. I conducted an observational study on a population of white-backed magpies, recording details of their demography, dispersal, breeding system, and parental care. In conjunction, I conducted a genetic analysis of the population, to determine if the genetic mating system matched the observed social system, to detect instances of extra-group mating, and to sex juvenile birds. Extra-pair paternity (EPP) is a common feature of the mating systems of many birds. The rate of EPP may vary between species, races and populations. I made a comparison of extra-group paternity (EGP) rates between two races of the Australian magpie, to determine if similar mating systems were being employed. The two populations had similar social structure, but differed in group size and dispersal. I predicted that dispersal differences would have a profound effect on the rate of EGP between the populations, as the population with the lower rate of dispersal and higher chance of breeding with a close relative would engage in EGPs more frequently. Eight microsatellite loci were used to determine parentage in the white-backed Australian magpie. The rate of EGP was found to be 44%. Dispersal rates were estimated from observational data. Over half of the juvenile magpie cohort from the previous breeding season leave the territorial group. These results contrast sharply with the results found by other researchers in a population of western Australian magpies (G t. dorsalis). In this population, 82% EGP is recorded and dispersal of juveniles is close to nil. The results indicate that dispersal rate is a potentially important predictor of rates of extra-group fertilisations between populations of this species, and suggest that females maximise their reproductive output by avoiding breeding with close kin. The reproductive success of a male bird is often correlated with measurable traits that predict his intrinsic quality. Females are thought to select mates based on their quality to gain their 'good genes'. Male Australian magpies of the white-backed race were trapped in two breeding seasons. Measurements were taken of morphometric and other characteristics in order to discover whether particular traits of males were associated with: a) number of fledglings produced in the territory per season; b) percentage of offspring sired in the territory; and c) whether females select males for their 'good genes'. The only variable that was correlated with number of territorial offspring was feather lice load. Males with high numbers of lice were less likely to produce territorial fledglings in one season and across both seasons. Males of inferior quality may be subject to increased conspecific territorial intrusions, leading to more time spent on defence, more failed breeding attempts, less time allocated to grooming and thus high parasite loads. Males that produced many territorial fledglings were more likely to gain genetic paternity of at least some of them, although again this was significant for only one season. Also, across both seasons, a high number of females in the group was correlated with increased paternity within the group. The general lack of correlation between the variables and level of genetic paternity may be due to females engaging in extra-group mating primarily to avoid breeding with a close relative rather than to choose a quality male. In this scenario, males would not have to be 'high quality', but merely genetically different to the female's social mate. Extra-group paternity (EGP) can affect paternal effort. It may also influence the helping effort of auxiliary birds in cooperatively breeding species. If helping is driven by kin selection, helpers should decline to provision unrelated young. Relatedness becomes difficult to assess however, when females mate outside the group. Alternative rewards may then become important in helper decisions. In my study population of Australian magpies, 38% of fledglings were sired by males outside the territorial group. In a second population (G. t. dorsalis), 82% of fledglings were sired by extra-group males. I observed within-group male and helper feeding effort over three breeding seasons in the first population and obtained data recorded over a single season in the second population. In both populations, males provisioned young regardless of relatedness, as did helpers. Males provisioned less than the nesting female on average. Paternal effort did not reduce with an increase in the rate of EGP between populations. In the population with intermediate levels of EGP, the white-backed magpies, I observed helpers in about half of the sampled territories that produced fledglings. Helpers did not increase the production of young. In the population with high levels of EGP, western magpies, I detected helping behaviour in proportionally more territories. It appears that Australian magpie helpers provide help in order to pay 'rent' and remain on the natal territory. I discuss these results in light of the differences between the two races of magpie and the major theories regarding male parenting decisions and helper activity. Finally, I examine the relatively high rates of EGP's in the Australian magpie from a phylogenetic perspective. Although inbreeding avoidance is strongly supported by this study as the major reason EGP is so common in magpie populations, there may be an element of phylogenetic inertia that maintains the frequency of this behavioural trait. I comment upon the use of single-population estimates of species EGP rates in comparative analyses, given the intraspecific variation discovered between Australian magpie populations. Future directions for the study of mate choice in the Australian magpie are outlined with a proposal to study variation at the major histocompatibility complex between mated pairs.
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Human and non-human primate preferences for faces and facial attractiveness

Griffey, Jack Alexander Fernall January 2011 (has links)
For humans and non-human primates (NHPs) the face represents a particularly important source of social information providing a means of conspecific recognition and cues to personal details including sex, age, and emotional state. The human face may also be fundamental in the transmission to conspecifics of other forms of socially relevant information including the display of facial traits associated with sexual attraction and mate choice. A wealth of experimental literature indicates that humans display robust preferences for certain facial traits associated with facial attractiveness including preferences for bilateral facial symmetry, facial averageness and sexually dimorphic faces and facial features. It is thought that these preferences have evolved via sexual selection, and may be adaptive, due to the role that these specific facial features play in reliably signalling to others the possession of heritable genetic quality or ‘good genes’. Therefore, from an evolutionary perspective, it is possible that certain facial preferences may represent an evolutionary adaptation for the selection of potential mate quality. However, despite similarities between human and NHP face processing and recognition abilities, the shared evolutionary history and social importance of faces to primates in general, and the potential importance of these preferences in the mate choice decisions of NHPs, very little research has investigated the extent to which NHPs display comparable preferences to humans for these specific facial traits. Consequently, the aim of the following thesis was to comparatively assess the general and more specific preferences that humans and NHPs display for faces and for traits associated with facial attractiveness. Data was compiled from preference studies examining the visual preferences displayed by two species of NHP (brown capuchins (Cebus apella) and chimpanzees (Pan troglodytes)) for conspecific faces manipulated for those facial traits associated with attractiveness, and from a single study of brown capuchins examining their general visual preferences for various types of facial information. Comparative preference studies were also conducted upon human adults and infants examining the visual and declared preferences that they display for manipulations of facial attractiveness. Data showed that despite possessing general preferences for certain faces and facial information, generally NHPs displayed no significant preferences for those facial traits thought to influences judgements of attractiveness in humans. Possible reasons for this absence of preference for these particular facial traits and the evolutionary implications of these findings are discussed.

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