Einleitung: Aufgrund der Heuknappheit der letzten Jahre werden zunehmend auch extensiv bewirtschaftete Wiesen für die Heuproduktion genutzt. Teil der artenreichen Wiesen ist jedoch auch das Vorkommen von potentiell toxischen Pflanzen wie die Herbst-Zeitlose. Inwieweit Pferde getrocknete Herbst-Zeitlose im Heu erkennen und meiden, ist unzureichend erforscht. Erfahrungsberichte von Landwirten sowie Fallberichte kommen zu widersprüchlichen Ergebnissen. Ziele der Untersuchungen: Das Ziel der vorliegenden Untersuchung bestand in der Beschreibung des Selektionsverhaltens von Pferden bei Vorlage von Heu, welches mit Herbst-Zeitlosen kontaminiert war. Tiere, Material und Methoden: Die Studie (TVV-Nummer 17/19) wurde mit sechs klinisch gesunden, adulten (Alter: 11 – 17 Jahre) Warmblutwallachen (durchschnittliches Körpergewicht (KGW) ± Standardabweichung (SD): 674 ± 85 kg) durchgeführt. Die Pferde wurden in Einzelboxen auf Stroh mit täglichem Zugang zu einem Paddock gehalten. Heu wurde, mit Ausnahme der Aufenthaltszeit auf dem Paddock, ad libitum zur Verfügung gestellt und durch 50 g eines kommerziellen Mineralfuttermittels (Hoeveler, Reformin Plus©) ergänzt. Leitungswasser war zu jeder Zeit frei verfügbar. Jedes Pferd erhielt zu unterschiedlichen Tageszeiten über eine Stunde Heu, welches mit 1 oder 2 % getrockneten Herbst-Zeitlosen kontaminiert war. Das Selektionsverhalten der Tiere wurde individuell beobachtet, protokolliert und ausgewählte Beobachtungsperioden mittels Videoaufnahmen aufgezeichnet. Um Intoxikationen zu vermeiden, wurden Abbruchkriterien definiert. Nahm ein Pferd zwei Herbst-Zeitlose auf, wurde die Beobachtungsperiode abgebrochen und das kontaminierte Heu entfernt. Die Beobachtungsperiode wurde an einem anderen Tag und zu einer anderen Tageszeit wiederholt. Musste die Beobachtungsperiode erneut abgebrochen werden, wurde das entsprechende Pferd aus dem Versuch ausgeschlossen. Alle Pferde wurden zu Beginn des Versuchs und anschließend alle zwei bis drei Tage allgemein klinisch untersucht (Herz- und Atemfrequenz, Beschaffenheit der Schleimhäute, Darmgeräusche, innere Körpertemperatur, Pulsation der Gliedmaßen). Ein Blutbild sowie biochemische Blutuntersuchungen aller Pferde wurden zu Beginn und am Ende der Studie durchgeführt. Sowohl das gefütterte Heu als auch die Herbst-Zeitlosen wurden auf die Menge ihrer Rohnährstoffe und Anteile der Faserfraktionen untersucht. Eine Messung der Colchicingehalte in den getrockneten Herbst-Zeitlosen wurde durchgeführt (Flüssigkeitschromatographie/Tandem-Massenspektrometrie). Die Ergebnisse der genannten Analysen wurden mithilfe von Microsoft Excel 2016® deskriptiv und mittels SPSS 27® statistisch ausgewertet. Ergebnisse: Keines der Pferde mied die Herbst-Zeitlose im Heu. Vier von sechs Pferden zeigten sogar eine Präferenz für die Pflanze und nahmen sie gezielt ohne umliegendes Heu auf. Lediglich ein Pferd mied die Herbst-Zeitlose während der ersten sechs Beobachtungsperioden. Innerhalb der siebten Beobachtungsperiode nahm es Anteile der Herbst-Zeitlose auf. Die Parameter der klinischen Untersuchung und die Blutwerte lagen zu jeder Zeit im physiologischen Normbereich. Bei der Messung der Rohnährstoffe konnten in der Herbst-Zeitlosen höhere Rohprotein- (CP: 12,5 ± 0,717 %) und Rohfettgehalte (CFAT: 3,86 ± 0,254 %), sowie ein höherer Anteil an stickstofffreien Extraktstoffen (NFE: 52,3 ± 1,24 %) als im Heu (CP: 7,84 ± 1,47 %; CFAT: 0,80 ± 0,237 %; NFE: 41,4 ± 1,99 %) nachgewiesen werden. Die Faserfraktion der Herbst-Zeitlosen (CF: 17,3 ± 0,837 %) stellte sich geringer als im Heu (CF: 34,5 ± 1,85 %) dar. Es wurde ein durchschnittlicher Colchicingehalt von 331 µg/g Trockensubstanz in der getrockneten Herbst-Zeitlosen gemessen. Schlussfolgerungen: Aufgrund der unselektiven, teils gezielten Aufnahme der Herbst-Zeitlosen durch die Pferde der vorliegenden Studie, sowie das stark gehäufte, nestartige Vorkommen der Herbst-Zeitlosen im Heu, können Vergiftungen durch kontaminiertes Heu nicht ausgeschlossen werden. Daher sollten Wiesen, auf welchen Herbst-Zeitlose wachsen, von der Heugewinnung ausgeschlossen werden.

In this thesis, we address the identification of biomarkers in high-dimensional omics data. The identification of valid biomarkers is especially relevant for personalized medicine that depends on accurate prediction rules. Moreover, biomarkers elucidate the provenance of disease, or molecular changes related to disease. From a statistical point of view the identification of biomarkers is best cast as variable selection. In particular, we refer to variables as the molecular attributes under investigation, e.g. genes, genetic variation, or metabolites; and we refer to observations as the specific samples whose attributes we investigate, e.g. patients and controls. Variable selection in high-dimensional omics data is a complicated challenge due to the characteristic structure of omics data. For one, omics data is high-dimensional, comprising cellular information in unprecedented details. Moreover, there is an intricate correlation structure among the variables due to e.g internal cellular regulation, or external, latent factors. Variable selection for uncorrelated data is well established. In contrast, there is no consensus on how to approach variable selection under correlation. Here, we introduce a multivariate framework for variable selection that explicitly accounts for the correlation among markers. In particular, we present two novel quantities for variable importance: the correlation-adjusted t (CAT) score for classification, and the correlation-adjusted (marginal) correlation (CAR) score for regression. The CAT score is defined as the Mahalanobis-decorrelated t-score vector, and the CAR score as the Mahalanobis-decorrelated correlation between the predictor variables and the outcome. We derive the CAT and CAR score from a predictive point of view in linear discriminant analysis and regression; both quantities assess the weight of a decorrelated and standardized variable on the prediction rule. Furthermore, we discuss properties of both scores and relations to established quantities. Above all, the CAT score decomposes Hotelling’s T 2 and the CAR score the proportion of variance explained. Notably, the decomposition of total variance into explained and unexplained variance in the linear model can be rewritten in terms of CAR scores. To render our approach applicable on high-dimensional omics data we devise an efficient algorithm for shrinkage estimates of the CAT and CAR score. Subsequently, we conduct extensive simulation studies to investigate the performance of our novel approaches in ranking and prediction under correlation. Here, CAT and CAR scores consistently improve over marginal approaches in terms of more true positives selected and a lower model error. Finally, we illustrate the application of CAT and CAR score on real omics data. In particular, we analyze genomics, transcriptomics, and metabolomics data. We ascertain that CAT and CAR score are competitive or outperform state of the art techniques in terms of true positives detected and prediction error.

Standard purification processes in large scale antibody production are largely dependent on Protein A chromatography. Protein A binds specifically to many subclasses of IgG with high affinity. However, in order to elute the proteins, the pH needs to be lowered. Since lowering of the pH can be detrimental to some antibodies, a milder purification process is of great interest. A variant of Protein A, called ZCa, has previously been engineered to bind to IgG in a calcium-dependent manner. The antibody binds to ZCa when calcium is present and releases when calcium is removed. For the IgG1 subclass, the elution still requires a slight lowering of the pH, which is why there is room for improvement of the molecule. A phage display selection has been performed with the aim to obtain calcium-dependent IgG1 binders that are able to release the antibodies upon calcium depletion at neutral pH. In addition, an attempt on increasing the alkaline stability of the binders was made. Sequence analysis of the selection output showed almost no indications of increased alkaline stability. Instead, M13K07 helper phages were exposed to new selections for increased alkaline tolerance which might be useful in future phage display selections. Even though the binders selected for in this project did show some promising characteristics, none of them were able to elute upon calcium depletion at neutral pH as aimed for. However, one of the variants did show promising results during most of the performed characterizations. Most interestingly, the elution properties of this variant could indicate a higher calcium-dependence in the interaction with the target than that of ZCa, although further characterizations need to be performed in order to draw any conclusions about possible improvements of this protein domain.

Browsing patterns in large herbivorous mammals are complex and decisions regarding food items occur at different levels depending on internal or external factors such as energy requirements and available food sources. A broader understanding of the behavior of animals living in habitats of economic interests for humans enables human exploitation with as little impact as possible on the animals' habitats. In this study, individual moose (Alces alces) tracks in the snow were surveyed in a mountainous environment with spruce-dominated forest, to map out what was browsed in relation to what was available in forests of two age classes: young and older. The following hypotheses were made: (1) every potential tree a moose passes will not be browsed and the browsed trees will be browsed to different degrees, and (2) the amount of available forage and the amount of used forage will differ between young and older forest. The moose tracks were followed on skis or on foot and all trees within browsing distance along a transect of 50 meters were counted and signs of browsing were recorded. Control transects (without fresh tracks) were also surveyed in the same forest areas where moose tracks were found. The data showed a higher proportion of available trees in young forest (60%) compared to older forest (40%) (all trees along the track transects), and a higher proportion of browsed trees in young forest (26%) compared to older forest (17%) (excluding Norway spruce, Picea abies). Downy birch (Betula pubescens) was the most abundant tree (56%) and Scots pine (Pinus silvestris) the least abundant (<1%). Only 20% of all available trees along the track transects were freshly browsed to some extent, and even among the more selected species no more than around 50% of all available trees were freshly browsed. In young forest, Eurasian aspen (Populus tremula), rowan (Sorbus aucuparia) and willow (Salix spp.) were the most selected by moose, while common juniper (Juniperus communis) was the least selected. In older forest, however, gray alder (Alnus incana) was the most selected, followed by willow and rowan, while downy birch was the least selected. No browsing on Ericaceous shrubs were recorded in any of the transects. The study underlines that many different factors influence moose browsing choices, but generally a varied diet is sought and forests of different age classes, not exclusively young forests, are used for winter foraging. / Betesmönster hos stora växtätande däggdjur är komplext och val kopplade till föda sker på olika nivåer beroende på inre och yttre faktorer så som energibehov och tillgänglig föda. En bredare förståelse om beteenden hos djur som lever i habitat där människan har ekonomiska intressen möjliggör mänsklig exploatering med så lite påverkan som möjligt på djurens livsmiljöer. I den här studien spårades individuella älgar (Alces alces) i snö i en fjällnära miljö med grandominerad skog för att kartlägga vad som betades i relation till vad som fanns tillgängligt inom två åldersklasser; ung och äldre skog. Jag ställde upp två hypoteser: (1) varje potentiellt födoträd som en älg passerar kommer inte att vara betat på och de betade träden kommer att vara betade i olika grad, samt (2) mängd tillgängligt foder och mängd nyttjat foder kommer skilja sig mellan ungskog och äldre skog. Älgspåren följdes på skidor eller till fots och alla träd inom betesavstånd längs en transekt om 50 meter räknades samt kontrollerades för bete. Även kontrolltransekter (utan färska spår) inventerades i samma skogsområden där älgspår återfunnits. Datan visade på en högre andel träd i ungskog (60%) jämfört med äldre skog (40%) (alla träd längs spårtransekterna), och en högre andel betade träd i ungskog (26%) jämfört med äldre skog (17%) (gran, Picea abies, undantaget). Glasbjörk (Betula pubescens) var det mest förekommande trädet (56%) och tall (Pinus silvestris) det minst förekommande (<1%). Enbart 20% av alla tillgängliga träd längs spårtransekterna var färskbetade i någon mån, och även hos de högre selekterade arterna var inte mer än runt 50% av alla tillgängliga träd färskbetade. I ungskog var asp (Populus tremula), rönn (Sorbus aucuparia) och sälg (Salix spp.) högst selekterade, medan en (Juniperus communis) var lägst selekterad. I äldre skog var däremot gråal (Alnus incana) högst selekterad följt av sälg och rönn, medan glasbjörk var lägst selekterad. Inget bete på bärris noterades längs någon av transekterna. Studien understryker att många olika faktorer påverkar betesval hos älg, men att en varierad diet generellt eftersträvas och skogar av olika åldersklasser, inte enbart ungskogar, nyttjas till födosök vintertid.

Sexually selected traits may also be subject to non-sexual selection. If optimal trait values depend on environmental conditions, then “narrow sense” (i.e., non-sexual) natural selection can lead to local adaptation, with fitness in a certain environment being highest among individuals selected under that environment. Such adaptation can, in turn, drive ecological speciation via sexual selection. To date, most research on the effect of narrow-sense natural selection on sexually selected traits has focused on precopulatory measures like mating success. However, postcopulatory traits, such as sperm function, can also be under non-sexual selection, and have the potential to contribute to population divergence between different environments. Here, we investigate the effects of narrow-sense natural selection on male postcopulatory success in Drosophila melanogaster. We chose two extreme environments, low oxygen (10%, hypoxic) or high CO₂ (5%, hypercapnic) to detect small effects. We measured the sperm defensive (P1) and offensive (P2) capabilities of selected and control males in the corresponding selection environment and under control conditions. Overall, selection under hypoxia decreased both P1 and P2, while selection under hypercapnia had no effect. Surprisingly, P1 for both selected and control males was higher under both ambient hypoxia and ambient hypercapnia, compared to control conditions, while P2 was lower under hypoxia. We found limited evidence for local adaptation: the positive environmental effect of hypoxia on P1 was greater in hypoxia-selected males than in controls. We discuss the implications of our findings for the evolution of postcopulatory traits in response to non-sexual and sexual selection.

In our daily lives, we encounter a multitude of emotional challenges in various contexts, necessitating the use of diverse emotion regulation strategies for adaptive responses (Aldao et al., 2015; Bonanno and Burton, 2013). These strategies require cognitive control, making them cognitively demanding processes (Gross, 2015b; Ochsner et al., 2012). Yet, it remains unknown whether different strategies impose different levels of cognitive effort. This thesis aims to address this gap in the literature by conducting a comparative analysis of the cognitive effort required for specific emotion regulation strategies. Our research takes a comprehensive approach to evaluating effort, utilizing physiological and subjective measures. In the field of emotion regulation choice, the role of effort remains less explored. We seek to deepen the understanding by not only investigating the self-reported reasons behind participants’ choice behaviour, but also by employing rigorous statistical analyses to identify the factors that influence these choices. Prior studies on the determinants of emotion regulation choice have faced certain limitations. While some determinants favouring specific strategies have been identified, there is a lack of information regarding the strategies that are not chosen. Additionally, it is unclear to what extent individuals prefer their chosen strategy over other available options. These issues can be addressed by assigning subjective values to all choice options, as these values are central to the decisionmaking process. This thesis has developed and validated a novel paradigm that measures the individual subjective values associated with emotion regulation strategies. We not only examined whether these values can effectively predict actual choice behaviour, but also delved into the variables that predict these subjective values, offering a holistic perspective on the complex interplay between cognitive effort and emotion regulation choice. To enhance comprehension on the impact of cognitive effort on emotion regulation, Study 1 and Study 2 aimed to compare the necessary effort between the two emotion regulation strategies distancing and expressive suppression. To our knowledge, this was the first work striving to comprehensively examine effort during emotion regulation by assessing it through various means. Two studies were carried out to examine the impact of cognitive effort on emotion regulation choice. Specifically, it was explored whether decision-making behaviour is more influenced by the cognitive effort required to implement the strategy or the effectiveness of the strategy. To answer these research questions, cognitive effort and effectiveness of distancing and suppression were quantified through subjective (ratings) and physiological (pupillometry, heart rate) measures. To explore choice behaviour, participants were instructed to finally employ either of the strategies again. Our findings highlight that the strategies did not differ substantially in terms of physiological effort, yet they did exhibit substantial disparities in the subjectively perceived effort. These differences between strategies also manifested in their choice behaviour: Two thirds of the participants opted for suppression once again, despite its lower effectiveness. Participants cited lower effort as the reason for their choice. By measuring effort through various means, these two studies provide a comprehensive understanding of the cognitive effort involved in emotion regulation. Furthermore, the results on the determinants of emotion regulation choice not only enrich research, but also provide starting points for practical applications. Paradigms commonly employed in emotion regulation choice research - as in Study 1 and Study 2 - suffer from a drawback as they entail a loss of information, providing only binary data concerning whether or not a strategy was chosen. However, it is unclear to what extent the favoured strategy was preferred compared to the alternative options. In Study 3, a registered report, the objective was to develop a novel paradigm to determine the subjective values attributed to each emotion regulation strategy at hand. The cognitive effort discounting paradigm by Westbrook et al. (2013) provided the foundation, but was developed and extended further. Participants completed an emotion regulation paradigm whereby they were prompted to employ three strategies - distraction, distancing, and expressive suppression. Next, we conducted our novel discounting paradigm to determine the subjective value of each strategy. In our study, we were not only able to show that subjective values predict subsequent choice behaviour, but that, in addition to self-assessed utility, subjective effort in particular was predictive of subjective values. Our innovative paradigm has extensive potential applications, even beyond the field of emotion regulation. By utilising this paradigm, it becomes feasible to ascertain subjective values of demand levels that lack any objective effort hierarchy. In summary, the present thesis makes an important contribution to deepen the understanding of the role of cognitive effort in emotion regulation and emotion regulation choice. Cognitive effort and regulatory success were comprehensively examined by assessing trait measures (questionnaires), subjective ratings and peripheral physiological measures (pupillometry, electromyography, electrocardiogram). Our main finding, which could be replicated across three pre-registered studies, shows that the use of strategies is associated with different levels of subjective effort for individuals. This leads to the majority of individuals choosing the strategy that is associated with less effort for them, rather than the strategy that is more effective. Finally, the thesis outlines a novel paradigm that enables the calculation of individual subjective values attributed to emotion regulation strategies. This facilitates a more comprehensive evaluation of the determinants of emotion regulation choice, as well as the strength of their preference for such strategies. Thus, it adds to the expanding literature on the field of emotion regulation flexibility by presenting starting points for assessing individuals’ flexibility and adaptability.:Contents Summary Preface 1. Theoretical Background 1.1. Fundamentals of emotions and emotion regulation 1.1.1. Emotions 1.1.2. Emotion regulation 1.2. The cognitive control of emotions 1.2.1. Cognitive control and cognitive effort 1.2.2. Cognitive effort and emotion regulation 1.3. Peripheral physiological consequences of intentional emotion regulation 1.4. Flexible emotion regulation 1.4.1. The extended process model of emotion regulation 1.5. Emotion regulation choice 1.5.1. A conceptual framework of emotion regulation choice 1.5.2. Determinants of emotion regulation choice 2. Scope of the thesis and study overview 3. Effort beats effectiveness in emotion regulation choice: Differences between suppression and distancing in subjective and physiological measures (Study 1 and 2) 3.1. Theoretical Background 3.1.1. Effort and emotion regulation 3.1.2. The present study 3.2. Study 1 3.2.1. Method 3.2.2. Results 3.3. Study 2 3.3.1. Method 3.3.2. Results 3.4. Exploratory analyses 3.4.1. Statistics 3.4.2. Results 3.5. Discussion 3.5.1. Effort plays a crucial role in the selection of an ER strategy 3.5.2. Individual differences in personality traits do not explain individual differences in arousal and effort 3.5.3. Subjective arousal and effort are not reflected in physiological arousal and effort 3.6. Limitations 3.7. Conclusion 4. Estimating individual subjective values of emotion regulation strategies 4.1. Introduction 4.2. Method 4.2.1. Ethics information 4.2.2. Pilot data 4.2.3. Design 4.2.4. Sampling plan 4.2.5. Analysis plan 4.3. Results 4.3.1. Participants and descriptive statistics 4.3.2. Confirmatory analyses 4.3.3. Exploratory analyses 4.4. Discussion 4.4.1. Ecological validity of subjective values of emotion regulation strategies 4.4.2. Trait character of subjective values 4.4.3. Limitations 4.4.4. Conclusion 5. General Discussion 5.1. Summary of results 5.2. The role of cognitive effort in emotion regulation 5.2.1. Effects of effort in the selection stage 5.2.2. Effects of effort in the implementation stage 5.2.3. Post-regulation effects of effort 5.3. Regulatory goals in emotion regulation 5.3.1. The interaction of regulatory goals and cognitive effort 5.4. Individual subjective values of choice options 5.4.1. Factors influencing subjective values 5.4.2. Subjective values: States or traits? 5.5. Methodological considerations 5.5.1. Experimental design 5.5.2. Assessment of physiological effort and arousal 5.6. Future directions 5.7. Conclusion References Appendix A. Supplementary Information Study 1 and Study 2 Appendix B. Supplementary Information Study 3 List of Figures List of Tables List of Abbreviations Erklärung

Die vorliegende Dissertation verbindet Ergebnisse aus neuroethologischen, verhaltensbiologischen, quantitativ genetischen und genomischen Ansätzen bei Feldgrillen (Gryllus), um neue Erkenntnisse über die Rolle von sexueller Selektion bei Artbildung zu erlangen. Es wird gezeigt dass multivariate Gesangspräferenzen von Grillenweibchen von wenigen Merkmalen abhängen und zwischen Arten ähnlich sind, während sich Männchengesänge in allen Merkmalen unterschieden. Verschiedene Ebenen der Gesangserkennung sind durch unterschiedliche Präferenzfunktionen charakterisiert. Multivariate Präferenzen können also gleichzeitig verschiedene Indikatoren für Paarungspartnerqualität aus den Gesangsmerkmalen erkennen. Eine polygene genetische Architektur der Gesangsmerkmale und der Präferenz wurde beobachtet und weist auf eine eher langsamere Divergenz hin, obwohl gonosomale Vererbung mehrerer Gesangsmerkmale höhere Evolutionsraten zulässt. Starke Kovarianz zwischen den Merkmalen die direkt sexueller Selektion unterliegen und Merkmale, die nicht direkt von Weibchen gewählt werden, zeigen, dass indirekte Selektion teilweise für die markante Divergenz der Gesänge verantwortlich sein könnte, trotz begrenzter Divergenz der Präferenzen. Ferner zeigte ein Artvergleich der multivariaten Gesangsmerkmale, dass die Form der Präferenzfunktion die Ausrichtung der Kovarianzen und damit die erwartete Selektionsantwort der männlichen Gesänge beeinflussen kann. Simulationen ergaben starke Hinweise auf Genfluss zwischen zwei nahverwandten Arten über einen langen Zeitraum . Nur wenige Contigs zeigten hohe genetische Divergenz und hohe Raten nicht-synonymer Polymorphismen. Diese stimmten aber mit Genen überein, die experimentell nachgewiesene Funktionen in neuromuskulärer Entwicklung und im Paarungsverhalten haben. Zusammen zeigen die Ergebnisse das Potential von sexueller Selektion bei der Entstehung und Aufrechterhaltung von reproduktiver Isolation zwischen Arten. / This thesis integrates insights from neuro-ethological, behavioural, quantitative genetics, and genomic approaches in field crickets to provide novel insights in the role of sexual selection in speciation, in particular focusing on speciation with gene flow. It was shown that song preferences depend on few traits and are similar across species while the male song has diverged strongly in all traits. Because the different levels of song recognition are characterized by different types of preference functions, it is conceivable that multivariate preferences can extract various cues for mate quality from different traits simultaneously. A polygenic genetic architecture was found for song traits and preferences, probably limiting divergence rates. However, sex-chromosomal inheritance of some song traits may have allowed for somewhat higher rates. Strong covariance was found between traits that are under sexual selection and traits that are not directly selected by females. This indicates that indirect selection may be responsible in part for striking multivariate divergence in the male calling song despite limited divergence in female preferences. Furthermore, comparing multivariate song traits among species showed that the shape of the preference function can affect the orientation of trait covariance and thereby the selection responses of the male song. Coalescent simulations revealed evidence for a long history of gene flow between two closely related cricket species. Only few contigs with high genetic divergence and high rates of non-synonymous SNPs were found, but many of those that were highly diverged matched genes with experimentally proven functions in neuromuscular development and courtship behavior. Together, these findings underline the potential for sexual selection to drive reproductive isolation.

Das Potential evolutionärer Veränderungen von lebensgeschichtlichen Merkmalen durch kommerzielle Fischerei fand in den vergangenen Jahren große Beachtung, wohingegen das evolutionäre Potential selektiver anglerischer Fischentnahme kaum berücksichtigt wurde. Durch intensive Beschreibung individueller Merkmale wie Verhalten, Lebensgeschichte, Morphologie und Physiologie der Fische habe ich die phänotypischen Korrelate der individuellen Angelfangbarkeit entflechtet. Anhand benthivorer und piscivorer Modellarten konnte ich so die Stärke und die Richtung anglerischer Selektion bestimmen. Zudem habe ich die Überlebenswahrscheinlichkeit und den Reproduktionserfolg dieser Fische gemessen, um das evolutionäre Potential anglerischer Fischereisterblichkeit abschätzen zu können. Ich konnte zeigen, dass die Risikofreude im Zusammenhang mit der Nahrungsaufnahme bei benthivoren Fischen dem stärksten Selektionsdruck ausgesetzt ist, während bei piscivoren Arten Aggression die bestimmende Eigenschaft war. Zudem waren Risikofreude und Wachstum positiv korreliert. Die intrinsische Fraßaktivität- und Geschwindigkeit erklärte, warum risikofreudige Fische selbst in Gruppen die höchste Hakwahrscheinlichkeit aufwiesen. Diese besonders leicht fangbaren Individuen wurden zudem mit höherer Wahrscheinlichkeit von Räubern in Teichen und in einem 25 ha großen Natursee gefressen, sodass anglerisch induzierte und natürliche Selektion bei juvenilen Fischen in die gleiche Richtung wiesen. Bei adulten, nestbewachenden Fischen konnte ich zudem zeigen, dass Eigenschaften, die zu einer erhöhten Fangbarkeit führen, auch den Laicherfolg steigern, sodass anglerische Selektion negative Auswirkungen auf den Reproduktionserfolg haben kann. Folglich kann bei hohem Fischereidruck ein anglerisch-induziertes Schüchternheitssyndrom entstehen, wodurch die Fangraten von der Fischbestandsdichte entkoppelt werden. Meine Ergebnisse deuten auf eine hohe Schutzwürdigkeit individueller Verhaltensdiversität hin. / The potential for fishing-induced evolution has been intensively discussed in recent years, but most studies have focused on life-history traits that directly or indirectly determine body size in the context of commercial fisheries. Much less is known about potential evolutionary changes in the context of passive angling fisheries. Using comprehensive phenotypic descriptions covering several behavioral, life-history, morphological, and physiological traits, I disentangled the phenotypic correlates of individual vulnerability to angling gear. Using both, benthivorous and piscivorous model species I identified the strength and direction of selection. I then compared survival and reproductive fitness of vulnerable and invulnerable individuals to predict the evolutionary potential of angling-induced selection. My research showed that boldness in the context of foraging is the most important trait under selection in passive fisheries targeting benthivorous species whereas aggression determines selection in piscivorous species. In addition, growth and boldness were positively correlated. Intrinsically high foraging activity- and speed likely explained why explicitly bold fish were caught more often. These highly vulnerable individuals also faced higher natural mortality at the juvenile stage in ponds and within a 25 ha natural lake. Thus, angling-induced selection and natural selection point into the same direction at the juvenile stage. However, using adult, nest-guarding fish, I also showed that angling-induced selection can severely impact reproductive fitness when behavioral patterns that determine fitness also affect vulnerability to angling gear. As a consequence, an exploitation-induced timidity syndrome can be assumed in highly exploited fish stocks leading to increasing shyness and reduced vulnerability of individual fish. My findings call for a promotion of behavioral diversity within natural fish populations.

Die vorliegende Dissertation behandelt die Frage nach Prozesskomponenten eines flexiblen Zugriffs auf im verbalen Arbeitsgedächtnis gehaltene "mentale Objekte" sowie nach deren Eigenschaften. Ein gängiges Arbeitsgedächtnismodell geht davon aus, dass das aktuell bearbeitete Objekt im Fokus der Aufmerksamkeit steht und beliebigen mentalen Operationen zur Verfügung steht, während die übrigen in einer "Region des direkten Zugriffs" aufrechterhalten werden. Ein Wechsel des mentalen Objekts führt zu zeitlichen Kosten, weil unter den Kandidaten eine erneute Objektselektion stattfinden muss (Oberauer, 2002). Mit Hilfe von vier Experimenten konnte gezeigt werden, dass diese Sichtweise erweitert werden muss: Mentale Objekte werden nicht für beliebige sondern spezifisch für die aktuelle Aufgabe bereitgestellt, während nicht mehr ausgewählte Objekte, deren Merkmalsinformation zerfällt, durch subvokales Rehearsal verfügbar gehalten werden und einer Neuselektion zunächst wahrscheinlich als phonologische Codes zugrunde liegen. Der Zugriff auf ein mentales Objekt erfordert somit neben der Objektselektion auch (anforderungsabhängig) Prozesse des Merkmalsabrufs und der Merkmalsselektion innerhalb des mentalen Objekts, welche die aktuell relevante Objektinformation bereitstellen. Sequenzen von Vergleichen mit wechselndem Zugriff auf Elemente einer Gedächtnismenge aus einstelligen Zahlen oder einsilbigen Wörtern ergaben höhere Objektwechselkosten, wenn die mentalen Objekte phonologisch ähnlich waren (Objektselektion), und wenn der Vergleich stärker semantische Objektinformation erforderte (Merkmalsabruf), sowie Kosten für einen Wechsel der relevanten Merkmale innerhalb eines Objekts (Merkmalsselektion), nicht aber bei Objektwechsel, der in jedem Fall die Selektion neuer Merkmale einschließt. Die Resultate sprechen für die postulierte Anforderungsabhängigkeit der Selektion im Arbeitsgedächtnis. / The dissertation aims at identifying component processes of access to "mental objects" from verbal working memory and characterizing the involved memory codes. In one of the current working memory models it is assumed that the object actually selected for processing is in the focus of attention and can be subjected to any upcoming mental operation while the remaining candidates are maintained within the "region of direct access". When the focus is moved to a new object this results in time costs since it requires the selection of a new object from the set (Oberauer, 2002). This task-independent view of working memory access has to be extended: The mental object in focus is usually selected for a certain (not any) operation while feature information of objects outside the focus of attention is subject to decay. Maintenance of objects currently not selected objects is probably realized by subvocal rehearsal that provides phonological codes of the objects - being the basis of a new object selection. Consequently, when switching mental objects there is not only object selection necessary but also feature retrieval and feature selection processes within the object that provide the task-relevant object information. Four Experiments were conducted. They consisted of sequences of comparisons using randomly changing elements from a memory set of one-digit numbers or monosyllabic german nouns. Object switching costs are higher when the memory set contains phonologically similar elements (object selection) and when the task requires semantic rather than superficial information (feature retrieval). There are costs for changing the relevant features within an object (feature selection) but not with an object switch that always includes the selection of new object features. The results strongly support the view of task-dependent selection processes in working memory.

Die Heuschreckenart Chorthippus biguttulus (Orthoptera: Acrididae) ist ein Modellorganismus für akustische Kommunikation. Die Männchen stridulieren durch Reiben des Hinterbeins gegen eine Flügelvene. Diese Dieser Gesang bietet Weibchen Informationen über Artzugehörigkeit, Geschlecht und u.U. die Qualität. Rezeptive Weibchen antworten auf arteigene und attraktive Gesänge. Ich untersuchte, welche Informationen der Männchengesang enthält, wie diese sich in Gesangsparametern manifestieren und welche Informationen rezipiert werden. Ich untersuchte Abhängigkeiten zwischen Gesang und Temperatur, Alter, Morphologie und Immunkompetenz. Ebenfalls testete ich auf eine Infektion mit Wolbachia sp.. Mit Playback-Versuchen wurde die Präferenz der Weibchen getestet. Der Sexualdimorphismus, Populationsunterschiede und Unterschiede zwischen Freiland- und F1-Populationen wurden untersucht. Es konnte gezeigt werden, dass die Männchengesänge in geringem Maße altersabhängig waren während sie Temperatur den Gesang stark beeinflusst. Länger andauernde Nymphenphasen induzierten veränderte Gesangsmerkmale. Größere und schwerere Beine korrelierten mit dem Onsetsowie der Versdauer und der Pausendauer. Die Phasenverschiebung der Hinterbeine hing stark mit der Störpausentiefe und der Thoraxbreite zusammen. Die Werte der Immunkompetenz korrelierten positiv mit dem Onset des Gesangs des jeweiligen Männchens sowie der Femurlänge. Die Weibchen bevorzugten Männchengesänge, die tiefe Offsets, lange Periode, bzw. Silben, geringe Störpausen und besonders lange Versdauern aufwiesen. Die Tiere zeigten einen hohen Grad an Sexualdimorphismus in Morphologie und Gesang. Ebenfalls waren starke Unterschiede in fast allen untersuchten Morphologiemerkmalen und den meisten Gesangsparametern verschiedener Populationen von Männchen festzustellen, wobei die Weibchenpräferenzen ähnlich waren und der artspezifische Parameter, das Silben-Pausen-Verhältnis, sich nicht unterschied. / The grasshopper Chorthippus biguttulus (Orthoptera: Acrididae) is a model organism for acoustic communication. The males stridulate by rubbing the hind legs against their forewings. The "song" is species-specific and contains information about the gender and perhaps about the quality. Receptive females answer by singing, if the male song is attractive. I worked on the question, which information about the male is in the song, which song parameters contain the information and which of these information is received by the females. I tested correlations between the song parameters and temperature, age, morphology and immunocompetence and I tested for an infection with Wolbachia sp.. The females’ preferences on male songs were tested with playback-experiments. I investigated the sexual size dimorphism and behavioral differences and the differences in these parameters of animals of different sites in Germany and of laboratory and field animals. The male songs were on a small scale age-dependent. Temporal parameters) depended very much from the temperature and decrease with higher temperatures. The developmental time correlated with the duration of the syllables, the onset variances and the gaps in the syllable. Males with longer and heavier legs produced higher onset, longer verses and longer pauses. The gaps in the syllable amplitude and the width of the thorax correlated with the phase shifting of the hind legs. The immunocompetence rate was positively correlated with the onset and the length of the femur. Females preferred male songs, which contained deep offsets, long periods (syllables), small gaps and long verse durations. The species showed a high degree on sexual dimorphism in morphology and the song parameters. The animals of different populations differed significantly in almost every morphology parameter and a lot of song parameters, while the syllable-to-pause-ration (species-specific) was constant. The females preference of the different sites were similar.