Transposable elements (TEs) have had immense impact on the structure, function and evolution of eukaryotic genomes. The work in this thesis identified Kat1, a novel domesticated DNA transposase of the hAT family in the yeast Kluyveromyces lactis. Kat1 triggers a genome rearrangement that results in a switch of mating type from MATa to MATα. Furthermore, Kat1 acts on sequences that presumably are ancient remnants of a long-lost transposable element. Therefore, Kat1 provides a remarkable example of the intricate relationship between transposable elements and their hosts. We showed that Kat1 generates two DNA double strand breaks (DSBs) in MATa and that the DDE motif and several other conserved amino acid residues are important for Kat1 cleavage activity. DNA hairpins were formed on one end of the DSBs whereas the DNA between the DSBs was joined into a circle. Kat1 was transcriptionally activated by nutrient limitation through the transcription factor Mts1 and negatively regulated by translational frameshifting. In conclusion, Kat1 is a highly regulated domesticated transposase that induces sexual differentiation.  In another study, we developed an assay to measure switching rates in K. lactis and found that the switching rate was ~6x10-4 events/generation. In a genetic screen for mutations that increased mating-type switching, we found mutations in the RAS1 gene. The small GTPase Ras1 regulates cellular cyclic AMP levels and we demonstrated that Mts1 transcription is regulated by the RAS/cAMP pathway and the transcription factor Msn2. Since Ras activity is regulated by nutrient availability, these data likely explains why nutrient limitation induces mating-type switching.

Male reproductive success in many mammals depends on their ability to allocate sufficient energetic resources to mating competition. Such costs are particularly pronounced in species with high levels of sexual body dimorphism, intense polygyny and distinct breeding seasons. I tested the hypothesis that male reproductive effort incurs significant energetic costs in wild chimpanzees (Pan troglodytes), a species with moderate sexual dimorphism, promiscuous mating and lack of breeding seasonality. My field studies combined behavioral observations on male chimpanzee behavior with non-invasive sampling of urinary C-peptide (UCP). UCP is a biomarker of insulin production that indexes individual energy balance. This dissertation contributes to the understanding of UCP as an energy assay by (1) validating the application of UCP for assessing dietary quality in bonobos (Pan paniscus) at Kokolopori, DRC and (2) providing a detailed assessment of diurnal variation in UCP levels in relation to short-term changes in food intake in chimpanzees at Kanyawara, Kibale NP, Uganda. I used UCP measurements in conjunction with full-day focal observations of male chimpanzees to assess the energetic costs of male-male competition for status and mating opportunities. Data on feeding time and rates of aggression suggested that males experience a reduction in energy intake and an increase in energy expenditure when highly attractive parous females were in estrus. UCP data supported these conclusions because males had lower UCP levels on mating days, and rates of aggression were negatively associated with UCP levels. Mean daily party size was also associated with low UCP levels, controlling for the presence of estrous females. Habitat-wide availability of preferred fruits was positively associated with male rates of aggression suggesting that energy availability mediates male investment towards energetically costly competitive behaviors. Contrary to expectations males who were most successful in obtaining copulations (high-ranking males) did not suffer higher energetic costs than lower-ranking males during periods of mating competition. Costs or reproductive effort include both direct competition for matings and long-term competition over social status. Maintenance of social rank over long periods appears to be particularly important in this slow-reproducing, long-lived and nonseasonally breeding primate. / Human Evolutionary Biology

Researchers must consider the role of context when examining the behavior and characteristics of an individual. An individual must alter development, characteristics, and behavior, to adequately meet the challenges presented within their ecology. The following dissertation presents three manuscripts that examine individual differences while considering the role ecological (spatial) and developmental (temporal) context plays on the individual. Each paper utilizes Life History Theory to examine and to integrate the study findings into a cohesive framework. Life history theory is an evolutionary-developmental theory that focuses on how allocation of bioenergetic and material resources to different developmental facets will have long-term implications for behavior, traits, and health. Each paper collectively highlights key contextual factors throughout the lifespan and seeks to understand how life history strategies emerge. Study I examined the role mother's behavior had on the development of the child unpredictability schema (i.e., worldview where children view their environment and others as unreliable). The study included 65 children and their mothers. Results revealed that child unpredictability schema was predicted by mother's mating and parental effort. A quadratic effect was also found, whereby child unpredictability schema became constant at lower levels of parental effort. Study II utilized retrospective reports of childhood parental effort from extended kin family, positive emotional environment, and traditional social values from a sample of 200 Mexican and Costa Rican college students. High levels of childcare assistance from patrilineal and matrilineal kin were associated with more positive family environment, and the association was partially mediated between kin care and slow life history. Positive associations were also found between matrilineal kin childcare and traditional Latin social values. Study III utilized a nationally-representative, all-female sample to test whether higher reproductive effort increases physical/mental deterioration in women. Results reveal that reproductive effort and illness were mediated by both antioxidant defenses and inflammation. The results of the three studies broadly support hypotheses generated from Life History Theory. Contextual factors during key developmental stages have an impact on how an individual will allocate time and bioenergetic resources - thus contributing to specific behavioral life history strategies.

It is not clear whether genes of the innate immune system of vertebrates are subject to the same selective pressures as genes of the adaptive immune system, despite the fact that innate immunity genes lie directly at the interface between host and pathogens. The lack of consensus about the incidence, type, and strength of selection acting on vertebrate innate immunity genes motivated this study. The goal of this work was to elucidate the general principles of innate immune receptor evolution within and between species. A phylogenetic analysis of the Toll-like receptor 5 (TLR5) in primates showed an excess of nonsynonymous substitutions at certain codons, a pattern that is consistent with recurrent positive selection. The putative sites under selection often displayed radical substitutions, independent parallel changes, and were located in functionally important regions of the protein. In contrast with this interspecific pattern, population genetic analysis of this gene in humans and chimpanzees did not provide conclusive evidence of recent selection. The frequency and distribution of a TLR5 null mutation in human populations further suggested that TLR5 function might be partially redundant in the human immune system (Appendix A). Comparable analyses of the remaining nine human TLRs produced similar results and further pointed to a biologically meaningful difference in the pattern of molecular evolution between TLRs specialized in the recognition of viral nucleic acids and the other TLRs (Appendix B). The general picture that emerges from these studies challenges the conventional idea that pattern recognition receptors are subject to an extreme degree of functional constraint dictated by the recognition of molecules that are essential for microbial fitness. Instead, TLRs display patterns of substitution between species that reflect an old history of positive selection in primates. A common theme, however, is that only a restricted proportion of sites is under positive selection, indicating an equally important role for purifying selection as a conservative force in the evolution of this gene family. A comparative analysis of evolutionary rates at fifteen loci involved in innate, intrinsic and adaptive immunity, and mating systems revealed that more promiscuous species are on average under stronger selection at defense genes (Appendix C). Although the effect is weak, this suggests that sexual promiscuity plays some role in the evolution of immune loci by affecting the risk of contracting infectious diseases.

Studies of demography and population structure give insight into important evolutionary processes such as speciation and diversification. In the present work I perform such studies in the genus Capsella, which has three species: C. grandiflora, an outcrossing diploid, C. rubella a selfing diploid, and C. bursa-pastoris a selfing tetraploid. These three species make a good model system for evolutionary studies because they encompass two major plant evolutionary processes: mating system shifts and polyploidization. To conduct my studies I have gathered a large number of samples across the distributions of each species and scored them both phenotypically and genotypically: more specifically we measured flowering time and collected DNA sequence data. In the tetraploid C. bursa-pastoris we applied an association mapping approach which takes population structure into account to search for genetic variation associated with variation in flowering time. Flowering time is an important and highly adaptive trait which is frequently subject to natural selection. We found evidence of association between flowering time and several single nucleotide polymorphisms (SNPs) within the flowering locus C (FLC) and cryptochrome 1 (CRY1). In the case of FLC these SNPs code for nonconsensus splice site variation in one of the two copies of the gene. The SNPs could potentially have functional consequences and our results imply that non-functionalization of duplicate genes could be an important source of phenotypic variation. Using a novel coalescent based approach, we investigated the polyploid origin of C. bursa-pastoris and find evidence supporting a recent autopolyploid origin of this species. In the two diploid species, I use sequence data to investigate population structure and demographic history and to assess the effects of selfing on C. rubella. Observed patterns of population structure and genetic diversity in C. rubella can be explained by a combination of both demographic history and mating system. Observed patterns in C. grandiflora suggest that the investigated populations do not deviate strongly from the SNM, which has rarely been found in modern demographic studies. Finally, we investigate the effect of sampling strategy on demographic inference. Extensive sampling both within and across our populations allow us to empirically test the effect of sampling strategy on demographic inference. We complement the empirical analysis with simulations and conclude that the effect of sampling strategy is in many cases weak compared with that of demographic events. Nevertheless, these effects are real and have the potential to lead to false inference and therefore sampling strategy should be carefully considered in demographic studies. / Felaktigt tryckt som Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Science and Technology 725

Männliche Säugetiere konkurrieren um eine nicht-teilbare Ressource (empfängnisbereite Weibchen) und sind üblicherweise das abwandernde Geschlecht, weshalb Kooperation zwischen Männchen der Intuition zu widersprechen scheint. Wenn die Kooperation jedoch für beide Partner vorteilhaft ist, indem sich z.B. ihr Paarungs-/Fortpflanzungserfolg erhöht, kann Kooperation eine plausible Strategie sein. Koalitionen können opportunistisch sein, also kurzfristig einen direkten Nutzen bieten, oder für einen zukünftigen Fortpflanzungserfolg und Aufstieg in der Rangordnung sorgen. Welche Art von Koalition auftritt, hängt von dem Konkurrenzpotential innerhalb einer Gruppe ab, das von der Fähigkeit des alpha-Männchen, rezeptive Weibchen zu monopolisieren, bestimmt wird. Es wird davon ausgegangen, dass Männchen den Rang bzw. die Stärke von potentiellen Koalitionspartnern und Kontrahenten abwägen müssen, um einen Partner zu rekrutieren, so dass die gemeinsame intrinsische Kampfkraft ausreicht um den Kontrahenten zu besiegen. Alternativ können Männchen vorherige Erfahrungen mit Gruppenmitgliedern nutzen, um zu entscheiden wen sie rekrutieren ("attitudinal partner choice") und verlässliche Partner wählen. Unter solchen Bedingungen kann die Wahl des Koalitionspartners durch Sozialbeziehungen beeinflusst werden. Diese Doktorarbeit sollte Aufschluss geben über die Kooperation zwischen Männchen, indem die Paarungskonkurrenz und Sozialbeziehungen von Männchen und der Einfluss von Koalitionen in einer gruppenlebenden, wilden Primatenart, dem Berberaffen (Macaca sylvanus), untersucht wurden. Dazu habe ich einen Bottom-Up-Ansatz genutzt, indem ich die vollständige Folge von Ereignissen analysierte, die zu Kooperation zwischen Männchen führte. Ich habe bestimmt, inwiefern Männchen den reproduktiven Zustand von Weibchen feststellen können, um das Potential zur Paarungskonkurrenz innerhalb von Gruppen empirisch abschätzen zu können. Ich habe das "Priority-of-Access"-Modell als Grundlage für eine Erforschung der männlichen Paarungskonkurrenz genutzt und habe die Faktoren untersucht, die zu Abweichungen von den Vorhersagen des Modells führen, vornehmlich das Verhalten der Weibchen und die männliche Koalitionsbildung. Die artspezifische Messung der Konkurrenz zwischen Männchen erlaubte eine kritische Evaluation eines mathematischen Modells, das konzipiert wurde, um verschiedene Typen von Koalitionsbildung innerhalb von Gruppen vorherzusagen (Pandit/van Schaik-Koalitionsmodell). Im Besonderen habe ich untersucht, wie die Vorhersagen des Modells zu empirischen Daten zweier Arten mit variablem Konkurrenzpotential (Berberaffen und Assam-Makaken, M. assamensis) passen. Die Sozialbeziehungen von Männchen wurden analysiert, um festzustellen, ob Berberaffen selbst in Zeiten intensiver Konkurrenz (während der Paarungszeit) langfristige Beziehungen formen. Schlussendlich wurde die Stärke männlicher Sozialbeziehungen untersucht um zu ermitteln, ob sie einen Anpassungswert durch die Kooperation in der Koalitionsbildung bieten, oder ob Koalitionspartner allein aufgrund ihres Dominanzstatus ausgewählt wurden. Es wurden Daten zweier Gruppen freilebender Berberaffen im Mittleren Atlasgebirge Marokkos von September 2009 bis August 2011 gesammelt. Ich habe über 2000 Stunden Verhaltensdaten aller Männchen in beiden Gruppen nach der Focus-Tier-Methode sowie ad libitum gesammelt, und 549 Koalitionen verschiedener Größe und unterschiedlichen Erfolges beobachtet. Zusätzlich wurden 155 weibliche Kotproben analysiert, um das Datum der Empfängnis mittels Enzymimmunassays von Gestagenmetaboliten festzustellen. Außerdem wurden weibliche Sexualschwellungen visuell eingestuft, um die Synchronität der Empfängnisse zu ermitteln. Die Analyse der weiblichen Hormonkonzentrationen zeigt, dass die Ovulation am wahrscheinlichsten im Zeitraum maximaler Sexualschwellung standfand. Allerdings konzentrierte sich das männliche Paarungsverhalten stärker auf die fertile Phase, was impliziert, das Männchen mehr als nur die Schwellungen an sich als Information nutzen können. Die Paarungshäufigkeit der Männchen stieg im Einklang mit dem sexualen Sozialverhalten der Weibchen. Bemerkenswerterweise zeigen meine Ergebnisse, dass Männchen gleichermaßen in Paarungen während der fertilen und nicht-fertilen (d.h. nach der Empfängnis) Phasen der Sexualschwellungen investieren. Obwohl diese zusätzlichen Sexualschwellungen das Monopolisierungspotential hochrangiger Männchen verringern, waren Paarungen zu Gunsten hochrangiger Männchen verschoben. Hochrangige Männchen haben aber keinen so großen Anteil der Paarungen erzielt, wie vom "Priority-of-Access"-Modell vorhergesagt wird. Weibchen haben regelmäßig Paarungen initiiert, in erster Linie mit mittelrangigen Männchen, was deren Paarungserfolg erhöhte, während Koaltionsbildung von Männchen deren Paarungserfolg unabhängig davon erhöhte. Regelmäßige Assoziationen mit Weibchen waren kostspielig für Männchen, da sie Ziele überbrückender Koalitionen ("bridging coalitions") wurden, was ihre zukünftigen Paarungsmöglichkeiten einschränkte. Hochrangige Männchen haben ihren Paarungserfolg nicht direkt mittels überbrückender Koalitionen ("bridging coalitions") erhöht, minderten aber den Einfluss des weiblichen Verhaltens. Außerdem bildeten Berberaffenmännchen langfristige Sozialbeziehungen die durch die höchst kompetitiven Paarungzeiten hindurch bestehen blieben. Männchen mit einer starken sozialen Bindung wurden mit höherer Wahrscheinlichkeit als Koalitionspartner rekrutiert, was nahe legt, dass für Männchen mehr als nur der Rang der verfügbaren Partner ausschlaggebend ist. Eine Prüfung des Pandit/van Schaik-Koalitionsmodells zeigte, dass unter hohem Konkurrenzpotential opportunistische Koalitionen genutzt werden sollten, um Zugang zu Weibchen zu gewinnen, die von hochrangigen Männchen monopolisiert sind. Indessen stimmten die empirischen Daten nicht mit den Vorhersagen unter mittlerem bis niedrigem Konkurrenzpotentials überein, bei dem männliche Affiliationen Rang-verändernde Koalitionen erleichtern könnten. Für diese werden vertrauenswürdige Partner benötigt, um die höherrangige Position zu verteidigen, sobald sie gewonnen wurde. Demnach können enge soziale Bindungen zwischen Männchen sowohl kurz- als auch langfristige Vorteile liefern, indem die Wahrscheinlichkeit, dass der Partner während einer Koalition abtrünnig wird, verringert wird. Zudem steht ein langfristiger Partner zur Verfügung, der erfolgreiche Rangveränderungen erleichtert wodurch enge soziale Bindungen letzlich sowohl den Status als auch den Paarungs-/Fortpflanzungserfolg erhöhen. Zusammenfassend erweitert meine Doktorarbeit die derzeitige Literatur über den Zusammenhang zwischen männlichen Fortpflanzungsstrategien, Sozialbeziehungen und Kooperation innerhalb von gruppenlebenden Säugetieren mit abwandernden Männchen. Durch die Untersuchung der vollständigen Beweiskette vom zwischenmännlichem Konkurrenzkampf hin zu Paarungserfolg und Kooperation durch das Schließen enger zwischenmännlicher Sozialbindungen, ergibt diese Studie ein umfassendes Bild mehrerer unabhängiger Forschungsansätze und könnte eine Vorlage für zukünftige Forschungsarbeiten bilden. Koalitionsbildung kann mutualistische Vorteile für beide Partner liefern, was nahelegt, dass Kooperation durch vorherige affiliative Interaktionen mit Gruppenmitgliedern durch "attitudinal partner choice" bestimmt sein könnte.

This dissertation project investigated fluctuations in estradiol and testosterone across the human menstrual cycle. During the part of the cycle when women are most fertile, women show stronger preferences for men with more masculine faces, and these preference changes may be related to changes in hormone levels during ovulation. The present study investigated preferences changes among women for higher testosterone men over the menstrual cycle as estradiol and testosterone in those women fluctuated. 32 women participated in this 5-week long study tracking their estradiol and testosterone levels and preferences for masculine men. Women with higher levels of estradiol preferred men who had higher levels of testosterone than women who had lower levels of estradiol. During ovulation, women were more like to find high testosterone men more attractive than other parts of the menstrual cycle. In addition to ratings of men, several other psychological tests were administered and examined for changes as a function of state and trait levels of hormones.

Male mating signals convey important mate-quality information to females and are regulated by androgens. Endocrine disrupting compounds (EDCs) are chemicals that interfere with proper hormonal functioning in exposed animals, causing altered hormone levels and resulting in changed reproductive characteristics, including mating signals. Altered signals can have ecological implications by influencing population and community dynamics and evolutionary implications via trans-generational reduction in signal reliability leading to reduced preference and eventual loss of the signal trait. I examined the effects of exposure to environmentally relevant concentrations of atrazine, a widely used herbicide and EDC, on mating signals and behaviors in male guppies, a sexually dimorphic freshwater fish. Guppies were exposed either during adulthood or embryonic development. Prolonged atrazine exposure during adulthood reduced the size of the carotenoid-based ornament, the number of courtship displays performed, and aggression towards competing males. Embryonic exposure did not affect survival to adulthood and the time to develop male-specific morphologies. But there was a trend for smaller genitalia, and the ornament size was significantly increased. Possible increases in immunocompetence as a result of slight estrogenecity may have allowed for greater carotenoid allocation to the ornament. Embryonic exposure also resulted in reduced courtship behavior, forced copulatory attempts and aggression towards competitors; female guppies found these males less attractive. The low dose had the strongest effects with embryonic exposure, indicating the importance of low-dose exposures. These studies highlight the effects of low and environmentally relevant doses of atrazine on mating signals and behaviors in exposed wildlife. A mathematical model was used to understand the evolutionary effects of EDCs on the optimal allocation of carotenoids between ornament and immunocompetence. Animals obtain carotenoids through their diet, and allocate some of this to enhance immune function and the rest to ornaments for mate attraction. The model replicates the disruption of carotenoid-based ornaments as a result of EDC-exposure, and predicts that signal reliability will be reduced. The model simulates an evolutionary shift in the optimal allocation if exposure spanned multiple generations, but signal reliability is not restored. Including additional selective forces like predation further suppresses signal reliability.

Beluga whales (Delphinapterus leucas) and narwhals (Monodon monoceros) are arctic specialists. Both species show philopatry to their summer grounds, though the reason for this site tenacity is not well understood. Aside from migration routes, little is known about other aspects of monodontid ecology, such as their mating and feeding ecology. An understanding of the feeding ecology of a species may provide some insights into their mating ecology, and vice versa. The purpose of this thesis is to relative testes mass and dietary biomarkers to gain insights in the mating and feeding ecology of both species, as well as possible links between the two. Relative testes and brain masses and body masses of odontocetes were collected from the literature and analysed for correlations between sexual size dimorphism (SSD), relative brain mass, and relative testes mass. Results indicate that odontocete species follow a pattern of increasing SSD with decreasing testes mass. An examination of reproductive tracts from belugas and narwhal collected across the Canadian arctic was performed to examine differences in beluga and narwhal mating systems. Belugas were found to have larger relative testes masses, and narwhal testes masses were correlated with tusk length, indicating that sperm competition may play a larger role in the beluga mating system than for narwhal, and narwhal tusks may be honest indicators of male fitness. Investigations of narwhal and beluga feeding ecology using dietary biomarkers were conducted. In the summer, belugas appear to be congregating and feeding in the estuary plume during the summer, as opposed to along ice floe edges in the spring. Spring diets are representative of diets consumed during the beluga mating season, and no sexual segregation in carbon isotopes or fatty acids was apparent. There was no evidence for sexual segregation in feeding habits outside the mating season, either. Conversely, narwhal showed some evidence of sexual segregation outside the mating season, and the sexes may be feeding in different food webs. Results suggest that belugas may have a more promiscuous mating system, while narwhals are more polygynous. Implications for conservation for both species are discussed.

Evolution is not always straight-forward, as selection pressures may differ between different generations of the same species. This thesis focuses on the evolution of life history of the model species, the Green-veined White butterfly Pieris napi. In central Sweden P. napi has two generations per year. The directly developing summer generation is short-lived and time stressed, compared to the diapausing generation. In paper I polyandry, defined as female mating rate, was shown to differ between generations but was unaffected by environmental factors. In paper II both males and females of the direct developing generation were shown to eclose more immature than the diapausing generation, indicating larval time constraints. Consistent with this, diapausing males mated sooner than direct developers. Directly developing females, however, mated sooner after eclosion than diapausing females, even though they are more immature. This was shown to negatively affect fecundity, but can pay off when the season is short. Paper III shows that directly developing males have less sex pheromones at eclosion than diapausers, and the differences in sex pheromone production is consistent with developmental time constraints and the differences in mating system. In P. napi and other polyandrous butterflies, males transfer a large, nutritious ejaculate at mating. Large ejaculates confer advantages under sperm competition, but as they are costly, males should adjust ejaculate size to the risk of sperm competition. In paper IV we found that males transfer on average 20% larger spermatophores under high male competition than at low competition. The same effect could be observed if we added male sex pheromone to the air in a mating cage without male-male competition. Paper V shows that males of the two generations respond differently to an increase in male-male competition, with diapausing males transferring larger spermatophores than direct developers at high male competition risk. / <p>At the time of the doctoral defence the following paper was unpublished and had a status as follows: Paper 5: Submitted manuscript.</p>