京都大学 / 新制・課程博士 / 博士(理学) / 甲第23737号 / 理博第4827号 / 新制||理||1690(附属図書館) / 京都大学大学院理学研究科生物科学専攻 / (主査)教授 曽田 貞滋, 准教授 渡辺 勝敏, 教授 中川 尚史 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DGAM

京都大学 / 0048 / 新制・課程博士 / 博士(理学) / 甲第20218号 / 理博第4303号 / 新制||理||1618(附属図書館) / 京都大学大学院理学研究科生物科学専攻 / (主査)教授 古市 剛史, 教授 Fred Bruce BERCOVITCH, 教授 平井 啓久 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DGAM

The male house sparrows has two assumed visible sexual traits which are 1) the colouration (or brightness) of the beak and 2) the size of the black badge on the bird’s throat and chest. Earlier research has shown that the testosterone concentration play an important part in determine the beak colour, with a higher testosterone concentration giving the bird a darker beak and as such making the male more attractive to females.     Even though stress has been counted for as a changing factor of phenotypes and behaviour it is not certain how vast effect stress has on different animals. This study is focusing on how and if the individuals fundamental stress level (fundamental corticosterone concentration) is affecting the morphological appearance, in this case the visible sexual traits (beak colour and badge size) and mask (an indicator of age), within the house sparrows in the Lundy Island population. In this study there was no relationship between beak colour and corticosterone concentrations, stating that beak brightness is not determined by fundamental stress. Likewise there was no relationship between the corticosterone concentrations and the size of the badge. Mask measurements in relationship to corticosterone showed no significant effect. These results indicate that there is no relationship between the corticosterone concentration in the blood and the mask size or the beak colour and badge size as visible sexual traits. / Många forskare är ense om att gråsparvshannen använder sig av två synliga karaktärsdrag för att attrahera honor. Den första är mörkhetsgraden på näbben och den andra är storleken på hannens svarta bröstlapp, placerad på hals och bröst. Tidigare forskning har visat att näbbfärgen påverkas kraftigt av hannens testosteron nivå och att en högre testosteron nivå leder till en mörkare näbb, vilket är mer attraktivt för honorna.    Även om stress har visat sig påverka både fenotyp och beteende hos många olika djurgrupper är det fortfarande oklart hur stor effekt stress har på olika djur. Denna studie fokuserar på hur och om den individuella fundamentala stressnivån (den fundamentala kortikosteron nivån) påverkar de synliga attraherande karaktärsdragen (näbbfärg och bröstlappsstorlek) hos gråsparvshannarna. I denna rapport analyseras även hannarnas masker, vilka fungerar som åldersindikatorer, i relation till de individuella kortikosteron koncentrationerna. Inget samband kunde hittas mellan näbbfärg och kortikosteron nivå hos de analyserade individerna. Likaså kunde inget samband hittas mellan kortikosteron nivån och storleken på hannens bröstlapp. Inte heller maskstorleken visade samband med kortokosteron nivån. Resultatet indikerar således att stress inte påverkar hannens sexuellt attraktiva karaktärsdrag eller mask.

6 ABSTRACT Conditional ornaments plays irreplaceable role in sexual selection in non-small part of by sexual reproduction reproducing animals. Fastidiousness of generating and later also carrying of these ornaments which show condition of their wearer, burdens also metabolism in non-small scale. This thesis tests hypothesis of mutual addiction between conditional ornaments, as the indicators of qualities of individuals and metabolism, as the most significant source of free radicals which are responsible for oxidative stress. The real weight of influence of ornament fastidiousness on organism, resp. on redox state, is tested in this thesis. Manipulations which were performed with individual males of model species should point how much the selected factors correlate each other. The barn swallow (Hirundo rustica) is the model species. Analyses of dates collected during trapping which were realized in breeding seasons in 2012 and 2013 does not show any important trends between observing variables. This fact is confirmed by minimal differences and inconsistent variability of levels of measured antioxidants - oxidoreductases, superoxide dismutase and glutathione peroxidase. The marginal effect of manipulations with one of the conditional ornaments which are presented in model species supports the hypothesis of...