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In migratory vertebrates, the optimal timing of successive life history stages is relatively inflexible. As a result, life history trade-offs that occur during breeding may influence individual success in subsequent stages because there is little time to mitigate negative costs that are incurred, or because the onset of subsequent stages is delayed. In migratory songbirds, understanding how breeding events carry over to influence individual success has been challenging because individuals are difficult to track once breeding is complete. I studied an island breeding population of migratory Savannah sparrows (Passerculus sandwichensis) and tracked individuals from breeding up until the onset of autumn migration. In Chapter 1, I investigated the effects of early life events on body condition during the pre-migratory period and first year apparent survival. I found that juveniles fledging from larger broods were in poorer condition at fledging, had lower fat stores prior to migration, and had lower first year apparent survival. In Chapter 2, I examined the effects of life history trade-offs made by adults during breeding on pre-migratory body condition and annual apparent survival. I did not find evidence for a trade-off between reproductive effort or date of breeding completion with annual apparent survival or body condition during the pre-migratory period, but instead found that adults with the highest reproductive effort and later dates of breeding completion were more likely to survive until the following year. In Chapter 3, I examined the effect of timing of breeding completion and fledging on the date of fall migration. I found that both variables had strong positive effects on date of departure. Together, my results suggest that successful migration in juveniles is influenced by early life events, but that any potential costs incurred by adults during the breeding season likely has little influence on survival during migration.

Alkylphenanthrenes such as retene (7-isopropyl-1-methylphenanthrene) are aquatic contaminants commonly found in anthropogenically-, industrially-, and petroleum-contaminated environments, and have been implicated in crude oil toxicity. In the early life stages (ELS) of fish, exposures to alkylphenanthrenes produce signs of toxicity typical of those observed in exposures to halogenated aromatic hydrocarbons, particularly to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). TCDD, the most toxic congener, serves as the basis of the current mechanism-based risk assessment model. The model assumes that congeners that produce TCDD-like toxicity share a common mode of action and act additively. The mechanism of TCDD-like toxicity is assumed to be mediated by the aryl hydrocarbon receptor (AhR), a ligand-activated transcription factor involved in the xenobiotic response (e.g., induction of cytochrome P450 1A enzymes; CYP1A) and in normal development. CYP1A enzymes are not involved in the mechanism of TCDD toxicity. Alkylphenanthrenes toxic to the ELS of fish are AhR ligands, but in contrast to TCDD, are readily metabolized by CYP1A enzymes. The byproducts of CYP1A metabolism have been implicated in retene toxicity. However, the target tissue of retene and the direct roles of AhR and CYP1A in retene toxicity are unknown, but are expected to be similar to those of TCDD. The results presented in this thesis suggest that in the ELS of fish: (1) the primary target of retene is the cardiovascular system (Chapters 2 & 5); (2) retene toxicity is stage-specific (Chapter 2); (3) the mechanism of retene toxicity is mediated by AhR2, and is independent of CYP1A enzymes (Chapter 5); (4) multiple CYP1A-independent toxicities can result from exposures to different mixtures of CYP1A inducing (retene) and CYP1A inhibiting (alpha-naphthoflavone or 2-aminoanthracene) PAHs (Chapters 3 & 4); and (5) multiple concentration-dependent mechanisms of toxicity (i.e., synergism and response addition) can occur in co-exposures of a CYP1A inducer (retene) with a range of CYP1A inhibitor (alpha-naphthoflavone) concentrations (Chapter 3). Thus, retene toxicity is mechanistically similar to that of TCDD toxicity, suggesting alkylphenanthrenes can be included in the current risk assessment model. However, the observed variable mixture toxicities and species differences in retene toxicity raise questions about the effectiveness of this model. / Thesis (Ph.D, Biology) -- Queen's University, 2009-01-13 12:10:31.373

Early-life experience has profound effects on the individual’s neurobiology and behaviour later in life. The rodent animal experimental model maternal separation (MS) was used to study this more in detail. The MS model involves short and prolonged postnatal separations simulating an emotionally safe and stressful environment, respectively. The aims of the thesis were to examine the impact of individual MS on ethanol consumption and on brain dopamine and serotonin systems in adult male rats. Furthermore, the influence of separation conditions on the short- and long-term consequences of MS on several neurotransmitter systems was examined. Rat pups were assigned to either litter-wise MS for 15 or 360 minutes (MS15l or MS360l) or individual MS for 15 or 360 minutes (MS15i or MS360i). Control rats were subjected to conventional animal facility rearing (AFR). Ethanol intake was assessed in a two-bottle free-choice paradigm. Neuropeptides were analyzed with radioimmunoassay, monoamines and metabolites with electrochemical detection and gene expression with qPCR. Using the MSi paradigm, minor effects on voluntary ethanol consumption were observed. However, the monoaminergic responses elicited by ethanol were dependent on the early-life environment. Furthermore, short- and long-term consequences of MS on serotonin, opioid, oxytocin and vasopressin systems were studied. Multiple neurobiological measurements in one and the same rat offered a unique possibility to examine the effects of duration (MS15 versus MS360) and condition (l versus i) of MS. Time-, region-, sex- and transmitter-specific effects were observed. More pronounced differences were seen in serotonin measures and oxytocin in young rats. In adults these differences in basal levels were normalized. Opioid peptides differed in stress-related brain areas in young rats and in limbic areas in adults. Rats subjected to the MS15l environment that relates to natural conditions generally exhibited a different neurobiological profile than other groups. AFR rats, i.e. conventional control rats, were more similar to the putative most stressful condition MS360. Taken together, the networks examined in the present thesis are important for the establishment of normal social behaviour and derangements in these systems may result in neurobiological changes leading to the susceptibility for psychopathological conditions later in life.

Fibromyalgia (FM) is a chronic pain syndrome of unknown etiology. It was previously suggested that patients with fibromyalgia were, in early life, often subjected to either psychological or physiological trauma. It is, in general, known that early life experiences and attachment to primary caregivers can influence physiological function in adult life, especially those functions related to stress vulnerability. Many studies have been performed on fibromyalgia patients but most of them investigated either psychological or physiological aspects. The purpose of this study was to investigate the psychological profile (attachment style, preferred way of thinking as well as prevalence of depression and anxiety) and physiological aspects (autonomic nervous system function and cortisol levels) simultaneously in an attempt to see whether a link exists between the two aspects and whether a specific psychoneurological profile could be discerned for fibromyalgia patients. Sixteen patients (14 females, 2 males) with fibromyalgia, and 15 age- and sex-matched controls (13 females, 2 males) were studied. Patients were diagnosed according to the American College of Rheumatology (ACR, 1990) criteria for fibromyalgia. The Patient Health Questionnaire gathered information on the patient’s past health problems, operations, accidents and the prevalence of traumatic events. The Fibromyalgia Impact Questionnaire and Review of Current Symptoms Questionnaire were completed to assess the severity of the disorder. The Experiences in Close Relationships – Revised Questionnaire determined attachment styles. Hemisphere dominance (preferred way of thinking) was evaluated by the Herrmann Brain Dominance Instrument (HBDI), heart rate variability (HRV) by recording R-R intervals and calculating time and frequency domain parameters and salivary cortisol levels by ELISA. Significant differences were seen between patients and controls for cortisol levels; the total number of symptoms; the number of adverse events in lifetime; anxiety and avoidance subscales of the ECR-R; FIQ total scores; and scores for scales within the FIQ. R-R spectral analysis revealed distinct lowered overall HRV in patients. An orthostatic test revealed a weakened shift towards sympathetic dominance upon standing. During a psychological stressor (filling out the ECR-R), the patients’ autonomic nervous system failed to respond with lower HRV as with the controls. As far as the hemispheric dominance of the patients was concerned, the majority appeared to be right-brain orientated with thinking styles preferences strongly influenced by limbic functions. Preference for thinking styles influenced by right limbic structures increased during stress. A link existed between anxiety and depression and the severity of the fibromyalgia symptoms. The results of individual psychological and physiological parameters found in this study are largely in concordance of that of other studies. Significant differences exist between the psychoneurological variables of fibromyalgia patients and healthy controls: The patient group in this study were characterised by a high prevalence adverse events, insecure attachment styles, high emotionality in the absence of rationality, multiple somatic symptoms, and altered stress-axes activity reflected in low HRV, an inability to mount an appropriate sympathetic response to acute stressors and elevated baseline cortisol levels. It can be concluded that fibromyalgia patients in the present study presented with a distinct psychoneurological profile. / Dissertation (MSc (Physiology))--University of Pretoria, 2007. / Physiology / unrestricted

Intraspecific aggression is a widely distributed, highly plastic behaviour throughout the animal kingdom and serves to secure resources, as members of the same species compete for identical ecological niches. But the costs can rapidly exceed the advantages. Over the past years, the two-spotted Mediterranean field cricket, Gryllus bimaculatus, has emerged to a model organism for studying the mechanisms underlying aggressive behaviour. Crickets implement seemingly complex decisions via the action of well-known neuromodulators with analogues in vertebrates including humans. This study shows that an individual´s decision to approach or avoid an agonistic stimulus is mainly shaped by social experiences gathered during nymphal development and early adult life. In particular, the chronic subjugation of nymphs by adult males in the breeding colony and the absence thereof lead to the establishment of distinct behavioural ethotypes shifting the answer to the question of whether inter-individual differences are nature or nurture in favour of nurture. Individuality in adult behaviour can thus result from social experiences during development alone. Moreover, the decision to approach or avoid a potentially agonistic stimulus is differentially modulated by the actions of the neuromodulators octopamine, serotonin and nitric oxide, which are released in response to social interactions. Interestingly, the social status dependent predisposed response to an antennal stimulus can be altered by octopamine alone. Furthermore, the present study reveals that the nitridergic and serotonergic system play a major role in the assessment of agonistic signals.:1 Introduction ...................................................................................................... 1 2 Methods ............................................................................................................ 6 2.1 Experimental animals .................................................................................... 6 2.2 Experimental groups based on social experiences and isolation time .................................................................................. 8 2.3 Evaluation of dominance and subordination ......................................... 10 2.4 Multiple wins and defeats ...................................................................... 12 2.5 Contests against a hyper-aggressive opponent .................................... 13 2.6 The mandible threat display in response to antennal stimulation and feeding ............................................................................. 13 2.7 The priming effect .................................................................................... 14 2.8 Influence of food as a resource ............................................................... 14 2.9 Set up and video tracking ....................................................................... 15 2.10 Evaluation of exploratory behaviour ..................................................... 16 2.11 Response to a single antennal touch with an adult male´s antenna ..................................................................................................... 17 2.12 Pharmacological treatment ...................................................................... 18 2.13 Data analysis ............................................................................................. 20 3 Results ............................................................................................................ 22 3.1 Responses of nymphs and adults towards conspecifics ........................... 22 3.2 Mandible threat display and the mandible spread angle .......................... 24 3.3 Influence of dominance and subordination ................................................. 26 3.4 Influence of prior antennal stimulation (priming) .......................................... 28 3.5 Influence of priming coupled with CDM ...................................................... 30 3.6 Influence of food as a resource .................................................................... 30 3.7 Effects of different social experiences during nymphal development on adult behaviour ................................................................. 31 3.8 Turning responses as a reaction to a single antennal touch with an adult male´s antenna ....................................................................... 34 3.8.1 Short term isolates ............................................................................... 34 3.8.2 Long term isolates ............................................................................... 38 3.9 Effects of neuromodulatory drugs on behavioural elements in STI and LTI crickets ............................................................... 43 3.9.1 Aggression ............................................................................................ 43 3.9.2 General motility .................................................................................... 46 3.9.3 Turning responses ................................................................................. 50 3.9.3.1 Influence of octopaminergic drugs .................................... 50 3.9.3.2 Influence of nitridergic drugs ............................................... 53 3.9.3.3 Influence of serotonergic drugs .......................................... 58 4 Discussion .................................................................................................... 68 4.1 Nymphal interactions and their consequences for adult behaviour .......... 68 4.2 The decision to approach or avoid an agonistic stimulus ........................... 72 4.3 The role of neuromodulators released in response to social experience .... 77 4.4 Overall conclusion and outlook .................................................................... 84 5 Summary .......................................................................................................... 86 6 Zusammenfassung ........................................................................................... 91 7 References ........................................................................................................ 98 8 Appendix .......................................................................................................... 109 8.1 Figures and Tables .......................................................................................... 109 8.2 Publications and published abstracts ............................................................ 111 8.3 Curriculum vitae ............................................................................................ 113 8.4 Acknowledgments ......................................................................................... 115

Early-life stress, consisting of several stressors appears to be associated with several impacts on the brain. The impacts of stress seem to be more vulnerable to the developing brain as it undergoes important changes during childhood. This thesis aims to present the association between childhood maltreatment, which is a form of early-life stress, and affected brain regions such as the hippocampus, prefrontal cortex, corpus callosum, and the amygdala. The findings in this thesis demonstrated the left hippocampus to be more vulnerable to the effects of maltreatment, corpus callosum appeared to be gender and maltreatment specific, indicating that the corpus callosum were more vulnerable to neglect in boys whereas in females the structure was more vulnerable to sexual abuse. The prefrontal cortex demonstrated a marked reduction in gray matter, and the amygdala showed increased activation in response to emotional facial expressions. Cognitive deficits as a result of earlylife stress were also discussed, showing that worse intellectual ability and the academic performance had been noted in children with exposure to early-life stress.

For many native, imperiled salmonid species, the prioritization of recovery and conservation efforts hinges upon the identification of a species most limiting life stage. The early life-history stage can be a limiting life stage for fish, and given the importance of the reproductive stage to overall persistence, there is a need to better understand the spawning ecology and early life history of many salmonids. The Logan River, in northern Utah, contains one of the largest metapopulations of imperiled Bonneville cutthroat trout (BCT) throughout the Bonneville Basin. Little research has evaluated the temporal and spatial distribution of BCT spawning nor quantified their early life-history survival. In the summer of 2008, I documented the spawning ecology of BCT and quantified their early life-history survival via egg-to-fry survival field experiments in four tributaries to the Logan River. I observed considerable variability in the timing, magnitude, and duration of spawning between study streams, in part as a function of a variable, multi-peaked hydrograph. I also conducted egg-to-fry survival experiments using incubation boxes and hatchery-fertilized, eyed cutthroat embryos and installed these boxes throughout my study streams. I found that survival was extremely variable within and among my study streams. For example, the variation I observed in survival appeared to be a function of fine sediment loads. Lastly, I observed that in the Logan River the timing of greatest intensity of both stream side and in-stream anthropogenic activities (e.g., livestock grazing, horseback riding) overlaps directly with the spawning and early life stages of BCT. Using my estimates of early survival, I revised a four-stage matrix population model for BCT in order to evaluate the hypothetical effects of anthropogenic impact on rearing areas. I determined that population growth rates are sensitive to perturbation at the egg-to-fry and fry to age-1 stages, and if even a small number of redds are destroyed through habitat degradation, a high degree of immigration of reproductively mature BCT is required to maintain the near-term persistence of this population. Future conservation efforts for BCT should be prioritized to protect areas where land-use activities are high during the sensitive spawning and early life-stage periods.

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