Animals trade-off limited resources among competing demands. Trade-offs are difficult to quantify because it is challenging to measure investment into disparate physiological systems using a common scale. Additionally, biologists desire methods to more precisely measure energy status in wild animals. I used stable isotopes to help solve both of these problems. I examined natural spatial and temporal variation in stable isotope signatures of wild lizards and found significant variation. In the lab, I was able to demonstrate the utility of nitrogen stable isotope ratios of uric acid pellets for measuring nutritional stress. By tracing labeled amino acids through the bodies of gravid female lizards, I demonstrated that vitellogenesis and wound healing compete for amino acids and quantified the direction and magnitude of the trade-offs. I showed that reproductive-immune trade-offs vary based on reproductive stage and energy availability, have effects on metabolism and immune function, and are influenced by hormonal mechanisms. My findings shed light on the interconnectedness of stable isotope endpoints and key physiological systems in animals. I showed that isotopic signatures of physiological stress can be reflected at a large scale in natural populations, and I made novel measurements of the size and direction of trade-offs, which were formerly limited to physiological and performance outcomes.

Phenological studies of coneflower on aspen range in Northern Utah showed that resumption of growth of mature plants begins at the time of snow melt and the initial or rosette stage is completed between mid-May and mid- June. The rate of growth in this stage is controlled by temperature, being greater at higher mean temperatures. The bolting stage is completed about 1 week after the initiation of stem elongation and the process of capitulum development is begun. Flowering is initiated between late July and mid- August. Cross-pollination is necessary for seed set which is completed by the end of August. Seed dissemination is begun at that time and is completed by the middle of September. Altitude appeared to have an effect on the extent of seed filling, since collections from higher altitudes had lower percentages of filled seeds. Seedling mortality increases as the season advances and reaches a maximum at the end of June when the associated species begin rapid growth. During the first season seedling growth is restricted to one unelongated stem and three leaves. Shoot/root ratios indicated that the main development during this season is in the roots. Optimum controlled conditions for seed germination are alternating temperatures of 25 C-15C with 8 hour photoperiods coinciding with the periods of higher temperature. A constant temperature of 25 C or alternating temperatures of 15 C-5C or constant darkness under any of the temperature regimes give lower germination percentages. Growth chamber studies demonstrated that coneflower is a long day plant since normal development to the seed setting stage is obtained under 18 hour photoperiods but not under 12 hour photoperiods when temperature alternations of 25 C-15 C are used. Low temperature stratification of the crown buds is not required for normal development. A series of field experiments showed that coneflower does not inhibit the growth of an important associated grass species--mountain brome. Laboratory experiments with foliage leachate gave no evidence of inhibitory effects on the germination or growth of other species. Force-feeding of sheep with whole dried plants collected at the seed set stage showed no toxicity for these animals. Total non-structural carbohydrates increase in the aerial parts of the plant as the growing season progressed up to the seed set stage and decreases thereafter until death of the aerial parts. Carbohydrates in the roots show a reverse trend. Two or three clippings applied to the rosette stage resulted in death of the plants. Failure of regrowth after these clippings was probably due to exhaustion of the supply of mature buds on the crown rather than being due to exhaustion of food reserves since significant concentrations of nonstructural carbohydrates were still present in the roots of these dead plants.

The channel catfish, Ictalurus punctatus (Rafinesque), was first introduced into Utah Lake in the summer of 1911, and has since been stocked in the lake on numerous occasions. It has only been in the last few years that the channel catfish has become an important game fish in Utah. As the value of the channel catfish, as a game fish, increased, it has become increasingly important to the state to maintain this species for present and future generations. This study was initiated in 1958 and completed in 19 60, and was financed by the Utah State Department of Fish and Game. Data on certain phases of the channel catfish life history were investigated to provide information to aid in management of this species. The following phases were studied: age and rate of growth; age composition of the population; reproduction success; food habits; movements; and extent of the fishing pressure.

The difference in evolutionary interests of males and females can select for traits that favour an individual??s fitness at the expense of their mate??s lifetime fitness. Despite the widespread occurrence of this sexual conflict over reproductive interactions, however, research to date has largely focused on the fitness costs imposed on females by manipulative males. Empirical evidence is particularly sparse for how mating can also be costly for males, the genetic structure of traits involved in reproductive interactions, and how sexual conflict can modify sexual selection in general. My aim was to explore the broader evolutionary consequence of sexual conflict and male-female interactions. In the nuptial-feeding Australian ground cricket, Pteronemobius sp., I used an experimental evolution approach to explore how diet and sexual conflict interact to determine the costs of mating. In the Australian black field cricket, Teleogryllus commodus, I used molecular and quantitative genetic approaches to characterise the fitness consequences and genetic basis of spermatophore attachment, a trait at the centre of inter-locus sexual conflict, and then related this to both condition and male attractiveness. Finally, in T. commodus, I quantified how sexual conflict alters the sexual selection acting on male sexual traits and how this in turn shapes genetic architecture and the persistence of additive genetic variance. My results demonstrate the complex nature of reproductive interactions between males and females. Importantly, I show that diet can mediate the expression of sexual conflict in a mating system and shape the evolution of male life-span. I also show that reproductive interactions influence the fitness benefits that both male and females obtain from mating in ways that are not predicted by current theory and that much of the potential for such traits to co-evolve is via a common genetic association with condition. Finally, I demonstrate that sexual conflict can profoundly modify the process and outcome of sexual selection, thereby influencing how additive genetic variation is maintained in a suite of male sexual traits. These results highlight the need for a greater integration of sexual conflict and sexual selection theory as the evolutionary potential and significance of sexual conflict may currently be underestimated.

<p>Syftet med mitt arbete är att få en fördjupad insikt i en lärares arbete, och få kunskap om hur stress och utbrändhet kan påverka arbetet som lärare. För att få denna förståelse har jag intervjuat en manlig lärare, Ove. Han har arbetat som lärare i fyrtio år. Genom att använda mig utav livsberättelsemetoden har jag fått tagit del av hans erfarenheter. I hans berättelse framkommer det att stress var inledningsvis något som var positivt för hans arbete. Han berättar att det är lätt att brinna för sitt arbete och lägga ner all sin tid och energi för det man tycker är roligt och intressant. Genom berättelsen får man ta del av hur den positiva stressen vänder, och Ove blir sjukskriven. Genom berättelsen framkommer Oves frustration över hur lärarrollen har förändrats genom åren. Det framkommer att det finns många faktorer som är avgörande hur en lärare ska fördela sin tid. Exempel på sådana faktorer är hur samhället och hur lärarrollen har förändrats genom åren.</p> / <p>The purpose with my work is to get a deeper insight into a teacher's job, and gain insight into how stress and burnout can affect the work as a teacher. To obtain this understanding, I interviewed a male teacher, Ove. He has worked as a teacher for forty years. The method I have used is a personal life story around this person. In his story it becomes clear that stress was initially something that was positive for his work. He says that it is easy to burn for their work and spend all their time and energy for what we think is fun and interesting. Through the story may take some of the positive stress turns, and Ove become sick. Through the story emerges Oves frustration with how the teacher's role has changed over the years. It is found that there are many factors that determine how a teacher should allocate their time. Examples of these factors is how society and how the teacher's role has changed over the years.</p>

Syftet med mitt arbete är att få en fördjupad insikt i en lärares arbete, och få kunskap om hur stress och utbrändhet kan påverka arbetet som lärare. För att få denna förståelse har jag intervjuat en manlig lärare, Ove. Han har arbetat som lärare i fyrtio år. Genom att använda mig utav livsberättelsemetoden har jag fått tagit del av hans erfarenheter. I hans berättelse framkommer det att stress var inledningsvis något som var positivt för hans arbete. Han berättar att det är lätt att brinna för sitt arbete och lägga ner all sin tid och energi för det man tycker är roligt och intressant. Genom berättelsen får man ta del av hur den positiva stressen vänder, och Ove blir sjukskriven. Genom berättelsen framkommer Oves frustration över hur lärarrollen har förändrats genom åren. Det framkommer att det finns många faktorer som är avgörande hur en lärare ska fördela sin tid. Exempel på sådana faktorer är hur samhället och hur lärarrollen har förändrats genom åren. / The purpose with my work is to get a deeper insight into a teacher's job, and gain insight into how stress and burnout can affect the work as a teacher. To obtain this understanding, I interviewed a male teacher, Ove. He has worked as a teacher for forty years. The method I have used is a personal life story around this person. In his story it becomes clear that stress was initially something that was positive for his work. He says that it is easy to burn for their work and spend all their time and energy for what we think is fun and interesting. Through the story may take some of the positive stress turns, and Ove become sick. Through the story emerges Oves frustration with how the teacher's role has changed over the years. It is found that there are many factors that determine how a teacher should allocate their time. Examples of these factors is how society and how the teacher's role has changed over the years.

The main aim of my dissertation is to understand the different ways problem youngsters cope with reality, construct identity and make choices of lifestyles. From a common starting point, the assessment home, I have by means of continual interviews followed fourteen youngsters, six girls and eight boys, for almost three years in the boundary zone between "the normal life" and "the deviating behaviour". In the assessment home they where defined as socially vulnerable and problematical. I was able to establish co-operation, got close and through narratives, gain insight into the "order" they gave themselves for experiences, thoughts and identity in choices of lifestyles. My interest was focused on life historical narratives and their own version of events. Even if different choices and lifestyles are experienced as individual they are not only a personal construction. Choosing is also the obvious way of doing gender, making a place for one's own thread, weaving it into the collective warp. Gender and reality differences leads to gender specific choices. Females gave priority to Intimacy before Identity and the males gave priority to Identity before Intimacy. I also found two types of social inheritance and life history scenarios that gave structure to choices and orientations. Choices of lifestyles were related to social action, ways of doing gender, dealing with social inheritance in situational ways. In an individual way actions had much to do with "a play around self-esteem" in which habits and routinized practice provided security and self-confidence. The power of habit gave security to create and recreate known figures even if the figures generated fear and respect in others' eyes. Social choices are decisions not only about how to act but who to be and the main theme for all the youngsters was to be somebody and to fit in somewhere. / <p>Diss. Umeå : Umeå universitet, 1998</p> / digitalisering@umu

Personality has been reported in a large variety of animal species, but it is not obvious why animals have personality. Variation in physiological traits, such as growth rate, should theoretically affect variation in behaviours and thus can explain why we observe variation in personalities. Growth rate is, theoretically, positively correlated with active personality types. Empirical studies have reported this pattern in different fish species, but there are not yet many studies on endothermic animals. I have therefore scored behaviours of 100 red junglefowl (Gallus gallus) chicks in four personality assays; novel arena, novel object, tonic immobility, and a proactive-reactive test, together with recording variation in growth rate of these individuals. The chicks individual growth rate (% day-1) were calculated and the relationship between personality and growth rate investigated. There was significant difference in growth rate between the sexes, where males grew faster than females, detected already at one week of age. However, no significant correlations between behavioural traits and growth rate were observed, indicating that personality seem to be independent of growth rate. Further studies should therefore investigate the generality of this finding, and alternative underlying mechanisms for variation in personality should be explored.

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