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Thesis (Ph. D.)--University of Wisconsin--Madison, 1984. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves [509]-522).

The aim of this study was to examine the influence of photoperiod on the hormonal induction of courtship and nest-building behaviour in the male ring dove (Streptopelia risoria). In the first experiment 24 intact males were divided into two groups and held on long (16L:8D) or short (8L:16D) photoregimes for five weeks. They were then paired with intact females and their behaviour recorded. Long day males exhibited significantly higher levels of bowing and nest-soliciting. In the second experiment males were again held on long or short photoperiods. Half of each group received daily injections of testosterone propionate. Testosterone treatment eliminated differences in courtship between the two groups, but nest-building remained significantly higher in hormone-treated long day birds. The experiment was then repeated using TP-treated castrates. In this case courtship did not vary between long and short groups, although nest-building was still greater under the long photoregime. These results indicate that photoperiod alters male courtship by stimulating endogenous androgen production. The influence on nest-building, however, appears to be least partially dependent upon some other mechanism. / Science, Faculty of / Zoology, Department of / Graduate

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Syftet med den här studien är att undersöka hur en grupp unga, svenska kvinnor mellan 20-30 år upplever de kvinnliga skönhetsidealen, samt att granska vad målgruppen anser om Doves Campaign for Real Beauty. Syftet är att studera om informanterna upplever kampanjen som ett steg i rätt riktning för att öka diskussionen och vidga begreppet skönhet. Med detta hoppas vi uppnå en större förståelse för hur unga svenska kvinnor ser på skönhetsidealen idag och om kampanjer likt Doves, är rätt tillvägagångssätt för att nå ett förändrat ideal. Teori: Delar av feministisk teori, receptionsstudier samt Stuart Halls teori om inkodning och avkodning. Metod: Två kvalitativt semistrukturerade fokusgruppsintervjuer med totalt sju kvinnor. Slutsatser: Informanterna skiljer på skönhet och skönhetsideal. De anser att Doves kampanj, Campaign for Real Beauty är ett steg i rätt riktning för ett förändrat ideal. Däremot ifrågasätter de Doves uttalade budskap med kampanjen och menar att det huvudsakliga målet skulle vara att öka försäljningen och stärka varumärket, snarare än att öka kvinnors självförtroende.

Preference is an important element in economic analysis, but usually regarded an inborn and exogenous characteristic. By the concept of natural selection, evolutionary game theory can explain lots of animal characteristics, including humans. With this idea, this paper extends the classical Hawk-Dove game to a two-period-life model, in which fights can cause deaths. We derive the population dynamics and the evolutiona-rily stable strategy. The competitive attitude and patience are determined by resource value and cost. And under a given common patience level, the evolutionarily stable strategy is a mixed strategy. But if the ¡§announcement effect,¡¨ an extra benefit from showing the winning record, is large enough, all-hawk may be the equilibrium. In ad-dition, under variable patient levels, the model can determine the equilibrium patience, and numerical simulation shows that dove-strategy accompanies a higher patient level than hawk.

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