Dissertations / Theses on the topic 'Dominance behaviors'

This study assessed how Constructivist theory accounts for verbal dominance. Conversations of rotating dyads were tape recorded, then coded for measures of dominance. Subjects completed a trait dominance scale and a constructivist personality test. Interpersonal rankings of dominance were found to be more consistent with observed behavior than trait dominance scores. Extreme trait dominance scores were associated with a constructivist measure indicating maladjustment. Dyads identified as more resistant to change were found to use fewer verbal control strategies; male/male dyads were characterized by direct, functional interactions. Dyads that were highly comfortable with one another utilized fewer verbal control methods. Lastly, interactions in which participants reported unfamiliar self-experiencing utilized higher levels of verbal control. Implications for group processing, assessment of dominance and sex differences are discussed.

The purpose of this study was to show that the degree of consistency that people demonstrate on personality measures is positively related to the degree to which behaviors representing the personality domains can be predicted. Thirty five female consistent personality scale respondents and Thirty eight female inconsistent scale respondents participated in small group discussions. The results showed that for all females, scale scores on the California Psychological Inventory subscaJe of dominance were predictive of three measures of dominance behaviors in the discussion group. Consistent personality scale respondents had no measures that were significantly correlated with the dominance scale score, whereas three measures were correlated with scale scores for female inconsistent scale respondents. Fischer's Z-transformations revealed no significant differences between the zero-order correlations for inconsistent and consistent groups and no significant differences were found between multiple correlations for the two groups. The results replicate past research on the prediction of behavior in single sex discussion groups, but fall to provide evidence that consistent scale respondents are more predictable than inconsistent scale respondents in the social dominance domain.

Levels of sociality vary depending on the costs and benefits associated with grouping behavior. Grouping species form either ephemeral aggregations due to resource availability, or structured groups based on familiarity of individuals. Because there are different costs and benefits associated with different types of groups, it is important to understand more about group structure before making predictions about specific behaviors. Female Hippopotamus amphibius are known to aggregate in the wild but the true nature of their grouping behavior is still not understood. My objective was to determine if captive female hippos form either ephemeral aggregations or social groups. Behavioral data, using continuous focal animal sampling and scan sampling, were collected on a group of nine captive female hippos housed at Disney's Animal Kingdom Theme Park. The behavioral data were used to analyze interactions between hippos, association patterns for kin and non-kin as well as familiarity, dominance hierarchy, and habitat preferences. My results support the hypothesis that hippos are forming social groups due to the attraction to particular individuals. There were more associations between kin than non-kin and also between individuals that have been together longer. Captive female hippos were also found to exhibit dominance patterns within the group. The results from this study may aid in the general understanding of hippopotamus behavior and aid in the captive management of hippos. Using my results as a starting point, research can begin looking at grouping patterns and its costs and benefits of sociality in wild hippopotamus populations.
M.S.
Department of Biology
Sciences
Biology MS

This study attempted to examine three aspects of Equus caballus foal snapping behavior. First, it suggested that the previous theoretical explanation for snapping established by behavioral researchers was incorrect. Second, as a means of suggesting an alternative hypothesis, this study proposed that snapping behavior could be a modified play response that was elicited when foals were confused by the complex social signals displayed by conspecifics. Finally, this project tested the aforementioned hypothesis by recording interactions between foals and conspecifics and analyzing the snapping intensity with each subjectâ s previous level of social experience. There were two indicators utilized to establish social experience. First, the â ageâ of the foal was employed as a measure of overall life experience and development. Second, the number of hours per day the foal was exposed to conspecifics gave an effective measure of the amount of time the subject had an opportunity to learn the complex Equine visual communication (referred to as â out-timeâ ).
Master of Science

The major purpose of this study was to determine whether a relationship exists between cerebral laterality dominance and leadership behavior and traits. An additional purpose was to determine whether a relationship exists between cerebral laterality dominance and gender, ethnicity, and educational position.

ELABORATIONS ON MULTIATTRIBUTE UTILITY THEORY DOMINANCE By David L. Vairo A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at Virginia Commonwealth University. Virginia Commonwealth University, 2019. Major Director: Dissertation director’s name, Dr. Jason Merrick, Supply Chain Management and Analytics Multiattribute Utility Theory (MAUT) is used to structure decisions with more than one factor (attribute) in play. These decisions become complex when the attributes are dependent on one another. Where linear modeling is concerned with how factors are directly related or correlated with each other, MAUT is concerned with how a decision maker feels about the attributes. This means that direct elicitation of value or utility functions is required. This dissertation focuses on expanding the types of dominance forms used within MAUT. These forms reduce the direct elicitation needed to help structure decisions. Out of this work comes support for current criticisms of gain/loss separability that is assumed as part of Prospect Theory. As such, an alternative to Prospect Theory is presented, derived from within MAUT, by modeling the probability an event occurs as an attribute.

The influence of authoritarianism, social dominance, and ingroup identification on ingroup favoritism and outgroup discrimination in a minimal group paradigm were investigated in this study. Possible effects of majority and minority group size interactions with these constructs were also examined. It has been previously shown that right-wing authoritarianism (Altemeyer, 1981) and social dominance orientation (Pratto, Sidanius, Stallworth, & Malle, 1994) influence ingroup favoritism and outgroup discrimination in Tajfel's (1978) minimal group paradigm (McFarland & Ageyev, 1992; Perrault & Bourhis, 1999; Sidanius, Pratto, & Mitchell, 1994). Majority and minority group status also influence behavior in minimal groups (Gerard & Hoyt, 1974; Otten, Mummendey, & Blanz, 1996; Sachdev & Bourhis, 1984; Simon & Brown, 1987). Based on motivational differences between authoritarianism and social dominance, individuals higher in authoritarianism were expected to display greater ingroup favoritism than those lower in authoritarianism, regardless of group size. Social dominance was expected to interact with group size such that individuals higher on this dimension in minority groups would identify less with the ingroup, as opposed to those in majority groups who would identify more, and display less favoritism toward the ingroup than those in majority groups. To create minimal groups, participants completed an estimation task and were told that their scores indicated they were either "overestimators" or "underestimators." Three conditions were established: Neutral (group size was unspecified), majority (one group was identified as being numerically large), and minority (one group was identified as being numerically small). Trait ratings (Thompson & Crocker, 1990) and Tajfel's (1978) resource allocation task were used to measure ingroup favoritism. Participants overall displayed ingroup favoritism on both dependent measures, although parity was used most on the Tajfel (1978) matrices. Neither authoritarianism, social dominance, nor any interaction between these constructs and group size significantly affected trait ratings. On the matrices, authoritarianism led to favoritism on only one of the six pull scores and did not interact with group size. Social dominance led those in the neutral condition to display greater ingroup favoritism. Contrary to predictions, social dominance led those in majority groups to select parity over favoritism, but did not affect those in minority groups. Finally, ingroup identification mediated the relationship between social dominance and ingroup favoritism on the trait ratings for those in neutral and minority groups, though not in the predicted direction. Those in minority groups gave more positive trait ratings to the ingroup rather than to the majority outgroup as their identification with the ingroup increased.

Senegalese sole is a flatfish species with increasing importance for the aquaculture industry due to its good performance (survival and growth) in captivity and high market price.However,one of the principal bottlenecks to the expansion of the species culture is the reproductive behavioural dysfunction in cultured males,which complicates establishing a closed cycle in captivity.The reproductive behavioural dysfunction is exhibited by the cultured males that do not participate in the courtship.Therefore, Senegalese sole production relies on wild males,which is unsustainable in the long term.With the aim to understand and look for solutions to this bottleneck,the present thesis focuses on different aspects of behaviour related to reproduction and the olfactory system. The effect of the presence of spawning wild Senegalese sole breeders on the reproductive behaviour and reproductive success of cohabiting cultured breeders was examined.Three groups were established,1 formed by cultures sole and 2 mixed groups (cultured and wild).Fertilised spawns were not obtained from the control group.However,fertilised spawns were obtained from the mixed-origin groups.Cultured males were observed to participate increasingly in the courtship and one cultured male fertilised 2 spawns.These results suggested a learning process in this species for behaviours associated to reproduction.With the olfactory analysis,the structure of the olfactory rosettes of 2 groups from different origin of Senegalese sole juveniles were compared.No significant differences in tissue structure,cell types and cellular distribution pattern were observed between origin specimens,however,differences were found between rosettes in number of lamellae and amount of goblet cells in the ridge region of the lamella,which were more frequent in the lower rosette.Related to the comparison of transcriptomic profiles (RNA-seq) of the upper rosette in cultured and wild sole mature males,the difference in transcripts of some olfactory receptors and other transcripts associated with the control of reproduction demonstrated clear differences in functionalities between origins.Related to the olfactory sensitivity of cultured sole, juveniles and adults to urine from mature conspecific (wild and cultured) was evaluated using EOG.Urine was confirmed to be a potent olfactory stimulus for juvenile and adult.In addition to this, urine from mature females evoked a small, but significant increase in plasmas levels of LH in mature males,further demonstrating that urine play a role in reproduction in this species.Related to dominance in Senegalese sole juveniles were used to conduct 2 dyadic tests (feeding response and territory) and group tests.This was the first study related to dominance behaviour in this species, which could be very relevant to the low participation in the parental contribution during the spawning season.Three parameters related to feeding response, 2 variables related to territory and 2 index in the group test were extracted to differentiate between dominant and subordinate sole.Moreover,2transcripts related to neurogenesis and neuroplasticity were differentially expressed between dominant and subordinate.In the present study three stress coping styles categories were found (proactive,intermediate and reactive) in Senegalese sole juveniles.Moreover,there were four transcripts related to metabolism and feeding behaviour which linked behavioural stress coping categories with brain gene expression.All together these advances strengthen the importance of these research lines as areas that can give a solution to the reproductive dysfunction that can enable the aquaculture industry to close the species life cycle in captivity to make sole culture sustainable.
El lenguado Senegalés es una especie de pez plano que está en constante crecimiento de producción dentro de la industria de la acuicultura debido a su buena capacidad de supervivencia y crecimiento en cautividad,además de poseer un elevado precio en el mercado.En cambio,uno de los principales problemas de expansión del cultivo del lenguado es la disfunción reproductiva asociada al comportamiento complicando el cierre del ciclo de vida de esta especie en cautividad.La disfunción reproductiva se ve en los machos de cultivo que no participan en el cortejo.Consecuentemente,la producción del lenguado recae en los machos salvajes siendo insostenible a largo plazo.Esta tesis tiene como objetivo principal entender y buscar posibles soluciones a este problema enfocándose en diferentes aspectos relacionados con la reproducción y el sistema olfativo.Primero se realizó un análisis de efecto de la presencia de lenguados salvajes que se reproducen,en el cortejo y el éxito reproductivo de los lenguados de cultivo,que no se reproducen.Se formaron 3 grupos,1 de cultivo (control) y 2 mezcla (cultivo y salvajes).No se obtuvo puestas fecundadas del grupo control,en cabio si se obtuvo de los grupos mezcla,viendose por primera vez un aumento de participación de los machos de cultivo,donde un macho de cultivo fertilizó 2 puestas.Estos resultados sugieren un posible proceso de aprendizaje del cortejo por parte de los machos de cultivo.Con el análisis del olfato,primero se realizó una descripción y comparación histológica de la estructura de ambas rosetas olfativas de dos grupos de lenguados juveniles (cultivo y salvaje).No se hallaron diferencias significativas en la estructura tisular, tipos de células y distribución celular entre lenguados de diferente origen, en cambio, se encontraron diferencias entre las rosetas en número total de lamelas y en cantidad de células goblet concentradas en la parte apical de las lamelas siendo más frecuente en la roseta inferior.Con referencia a la comparación transcriptómica (RNA-seq) de la roseta superior en machos maduros salvajes y de cultivo,hubo diferencias significativas en transcritos asociados a receptores olfativos y de reproducción mostrando claras diferencias en la funcionalidad de la roseta en lenguados de diferente origen.En referencia a la sensibilidad olfativa a la orina del lenguados maduros medida a través del EOG,se demostró que la orina es un potente estimulante olfativo en lenguados juveniles y adultos de cultivo y además el incremento de LH en plasma de los machos adultos utilizados en este estudio demostró que la orina juega un papel importante en la reproducción de dicha especie.En referencia a los estudios de dominancia en lenguados juveniles,se utilizaron 2 pruebas diádicas(alimentación y territorio) y una grupal extrajeron 3 parámetros de dominancia asociados a la alimentación,2 variables asociadas al territorio y 2 índices en el test grupal los cuales diferenciaron entre dominantes y subordinados.Además hubo dos transcritos relacionados con la neurogenesis y la neuroplasticidad que se expresaron diferencialmente entre dominantes y subordinados.Este estudio ha sido el primero en reportar la dominancia como comportamiento en esta especie, la cual podría ser relevante debido a la baja contribución parental durante la época de puesta.Así mismo,se determinaron 3 categorias de estilos de afrontamiento al estrés (proactivos,intermedios y reactivos) en lenguados juveniles.Se encontraron 4 transcritos asociados al metabolismo y comportamiento de alimentación que relacionó los prfiles de comportamiento con la expresión génica cerebral en lenguados juveniles siendo genes importantes a nivel biolígico y funcional. Conjuntamente estos avances fortalecen la importancia de estas líneas de investigación como áreas que pueden dar solución a la disfunción reproductiva pudiendo cerrar el ciclo de vida del lenguado en cautividad para hacer el cultivo sost
El llenguado Senegalès es una espècie de peix pla que està en constant creixement de producció dins de la industria de l'aqüicultura degut a la seua capacitat de supervivència i creixement en captivitat,a més de posseir un elevat preu al mercat.En canvi,un dels principals problemes d'expansió del cultiu d'aquesta espècie és la disfunció reproductiva associada al comportament que complica tancar el cicle de vida del llenguado en captivitat.La disfunció reproductiva s'observa als mascles de cultiu que no participen al seguici.Conseqüentment,la producció del llenguado Senegalès depèn dels mascles salvatges el qual es insostenible a llarg termini.Esta tesi té com objectiu principal entendre i buscar possibles solucions a aquest problema enfocant-se en diferents aspectes relacionats amb la reproducció i el sistema olfactiu.Primer es realitzà un anàlisi d'efecte de la presència de llenguados salvatges que es reprodueixen en el seguici i l'èxit reproductiu dels llenguados de cultiu que no es reprodueixen.Es formà 3 grups,un de cultiu (control) i 2 mescla (cultiu i salvatges).No s'obtingué posts fecundades del grup control,en canvi si s'obtingueren dels grups mescla,veient un augment de participació dels mascles de cultiu per primera volta,on un mascle de cultiu va fertilitzar 2 postes.Aquests resultats suggereixen un procés d'aprenentatge del seguici per part dels mascles de cultiu.Amb l'anàlisi de l'olfacte,primer es realitzà una descripció i comparació estructural histològica de ambdues rosetes olfactives de 2 grups de llenguados juvenils dels dos orígens.No es trobà diferències en l'estructura tissular,tipus de cèl·lules i distribució entre llenguados de diferent origen,en canvi,es trobà diferències entre rosetes en nombre total de lamel·les i quantitat de cèl·lules goblet concentrades a la part apical de la lamel·la més freqüents a la roseta inferior.En referència a la comparació transcriptómica (RNA-seq) de la roseta superior en mascles madurs salvatges i de cultiu,es trobà diferències en transcrits associats a receptors olfactius i de reproducció mostrant clares diferències en la funcionalitat de la roseta en llenguados de diferent origen.En referència a la sensibilitat olfactiva de l'orina de llenguados madurs mesurada amb EOG,es demostrà que l'orina es un potent estimulant olfactiu en llenguados juvenils i adults de cultiu i l'increment de LH en sang dels mascles adults utilitzats en aquest estudi demostrà que l'orina juga un paper important en la reproducció d'aquesta espècie.En referència als estudis de dominància de llenguados juvenils utilitzant 2 probes diàdiques (alimentació i territori) i 1 grupal,van extraure 3 paràmetres de dominància associats a l'alimentació,2 variables associades amb el territori i 2 índex en el test grupal els quals diferencià entre dominants i subordinats.Aquest etudi ha sigut el primer en reportar la dominància com a comportament en aquesta espècie,la qual podria ser important degut a la baixa participació parental durant l'època de posta.Així mateix,es determinà 3 categories d'estil d'afrontament a l'estrès (proactius,entremitjos i reactius) en llenguados juvenils.Es van trobar 4 transcrits associats al metabolisme i comportament d'alimentació sent tots ells gens d'importància biològica i funcional que s'expressaren diferencialment entre perfils de comportament.Conjuntament aquests avanços enforteixen la importància d'aquestes línies d'investigació com àrees que puguin donar solució a la disfunció reproductiva podent tancar el cicle de vida del llenguado en captivitat per a fer la producció d'aquesta espècie sostenible en l'industria de l'aqüicultura.
Fatsini Fernández, E. (2017). Reproduction, olfaction and dominance behaviour in Senegalese sole (Solea senegalensis) [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/81550
TESIS

Individual differences in autonomic nervous system responsiveness have been linked to a variety of physical disorders and personality and behavioral tendencies. The present study attempted to correlate specific personality characteristics hypothesized to be associated with either sympathetic or parasympathetic dominance based on the work of M. A. Wenger. The Clinical Analysis Questionnaire Personality Inventory, a physical disorders questionnaire, a self-report stress measure, and seven psychophysiologic tests were administered to 60 undergraduate students in an introductory psychology class at North Texas State University. The results provided limited support for the hypotheses. A skewed population with 50 of the 60 subjects achieving scores indicative of sympathetic dominance occurred. Statistical comparison (t-tests) of the CAQ personality traits, and clinical factor scores of these 50 subjects labeled sympathetic dominant with CAQ norms for college students revealed means on five personality traits and three clinical factors were significantly different for the sympathetic dominant group at the .05 or greater level of significance. These findings were interpreted as limited support for Wenger's work and for the positions of Acker and Kagan that individuals with more reactive sympathetic nervous systems tend to have difficulty binding anxiety, poor emotional controls and outlets, ambivalence about interpersonal relationships, and a need for group acceptance.

Factors associated with rank position are poorly understood whereas even fewer studies assessed if benefits were associated with increased rank position when resources were unlimited. I assessed whether age, body mass, size, and testosterone levels were important in rank establishment among 132 captive female white-tailed deer (Odocoileus virginianus. I also assessed if the benefit metrics of improved body condition, decreased stress level, and earlier parturition date were related to rank position. Deer in each of 9 study pens had a linear hierarchy with a mean h' of 0.39 (SD = 0.09). Rank position was moderately related to age (P < 0.1) and was strongly related to body mass and size (P < 0.01). There was no relationship between benefit metrics and rank position (P < 0.1). Although increased body mass, size, and age improved rank position there were no benefits associated with increased rank when resources were unlimited.

Factors influencing the stability of matrilineal dominance hierarchies were investigated in a feral troop of vervet monkeys (Cercopithecus aethiops sabaeus) in Barbados. Changes in the matrilineal dominance hierarchy were investigated over a 12-year period (1979-1991). Matrilineal ranks remained unchanged for the first 7 years (stable period), reversed on several occasions over the next 3.5 years (unstable period), and have re-stabilised for a further 3.5 years to present date. The frequency distribution of non-matrilineal supports in different social contexts, the lower support frequency in unstable than stable periods, and in particular the high reciprocity evident in non-matrilineal support exchanges, suggest that non-matrilineal support is better explained by reciprocal altruism than by mutualism in vervet monkeys. (Abstract shortened by UMI.)

Competition for resources plays an important role in natural selection, creating winners and losers. Winners become socially dominant, obtain resources and so increase their fitness at the expense of losers. Provided they are heritable, phenotypic traits promoting competitive success will be inherited by subsequent generations. Thus, while resource dependent traits (e.g. growth) that rely on competitive outcomes are widely recognised as being under strong selection, this is also likely to be the case for those traits that determine competitive ability and social dominance. In addition, competition is expected to be an important source of stress, for example, harassment of subordinates by dominant individuals. Consequently individual fitness may depend not only on the ability to win resources, but also on the ability to cope with stress. This thesis proposes that social dominance is not just a simple consequence of body size or weaponry, but rather that the interplay between growth, repeatable behavioural characteristics (i.e. personality), and the ability to cope with social and environmental stressors are equally important factors. Thus the dynamic of dominance arises, a model that highlights the expectation of complex relationships between traits causal and consequent to social dominance. Here, empirical studies of Xiphophorus sp. are used to test each element in the model. First the concept of individual personality is explored, asking to what extent it is really stable over long periods of time (equivalent to lifespans). Next, the links between behaviour, physiological stress and contest outcome are considered and, using a repeated measures approach, the hypothesis that individuals differ in stress coping style is evaluated. Finally, using a quantitative genetic approach the additive genetic variance-covariance matrix (G) is estimated between behavioural and life history traits under experimentally manipulated levels of competition. In this way the contribution of genetic and environmental effects to the patterns of trait (co)variation that make up the dynamic of dominance is assessed.

Social status is commonly established among individuals within groups of animals. Despite this common characteristic of social animals it is still unclear how individuals establish their status. I investigated the relationships between morphology, posture and behaviours with social status in red junglefowl hens. The hens tested were measured (weight, comb length, comb height and tarsus length) and exposed to three different behavioural tests (novel arena, novel object and interaction test). None of the morphological features were associated with social status. However, dominant hens initiated the first encounter in a dyad interaction and performed a higher proportion of aggressive encounters against the opponent. The dominant hens were also the ones displaying more spread tail feathers than the opponent after status being established. Aggressiveness and social status is strongly linked, showing that there is a scope of behaviours to affect the establishment of status.

This study uses life-history interviews with militarized men to describe a version of masculinity constructed in the local context of a non-profit motorcycle club. The study describes the details of one group’s specific gender nature, the result of which expands and challenges our understanding of the masculinity master narrative. The findings establish that both hegemonic and nonhegemonic attitudes, beliefs, and behaviors co-exist in the local dominant masculine norm, thereby disrupting traditional distinctions of masculinity as being either hegemonic or nonhegemonic. Key future research implications support the study of context as essential to the study of gender construction, challenge descriptions of masculinity as being either hegemonic or nonhegemonic, and posit the relevance of veteran peer groups in supporting post-military resocialization.

Organisms are frequently faced with uncertainty regarding how best to exploit vital resources, and may benefit from collecting information about their distribution through space and time. However, the ways in which competition over resources might systematically facilitate or constrain an individual's ability to use information has been largely overlooked. In this thesis, I develop a conceptual framework for considering how the distribution of limited resources might underpin interdependencies between competition and information use. I focus on the evolutionary ecology of relationships between social dominance and social information use. I begin with an observational study of wild chacma baboons (Papio ursinus) suggesting that, when resources can be monopolised, individuals with low competitive ability are limited in their ability to use social information. Building on these findings, I then develop a general model exploring selection on social information use in a competitive context across three axes of 'resource ecology' (scarcity, depletion rate, monopolisability). This study makes predictions regarding the resource conditions under which competitive ability might constrain social information use, and the potential importance of social information use in the evolution of social dominance. I go on to test these predictions in chacma baboons using a field experiment. This experiment also explores whether the predictability of resource distribution might facilitate the decoupling of social information use from the competitive context in which it was collected. Taken together, these findings provide general insights into the combinations of ecological conditions and behavioural mechanisms that should underpin the benefits of social dominance. I end by building a simple population matrix model to study social dominance using an eco-evolutionary approach, in which feedback loops between ecological and evolutionary processes are considered. By modelling relationships between dominance rank and survival, reproduction, inheritance, and development, I am able to derive estimates of long-term fitness associated with dominance. Using these estimates, I generate predictions regarding how dominance hierarchies should impact the dynamics of group stability, viability, and fission.

Doctor of Philosophy
Despite the number of bilinguals and speakers of English and Mandarin worldwide, up till now there have been no investigations of stuttering in any of the Chinese languages, or in bilinguals who speak both English and Mandarin. Hence, it is not known whether stuttering behavior in Mandarin mimics that in English, or whether speech restructuring techniques such as Prolonged Speech produce the same fluency outcomes in Mandarin speakers as they do for English speakers. Research into stuttering in bilinguals is available but far from adequate. Although the limited extant studies show that bilinguals who stutter (BWS) may stutter either the same or differently across languages, and that treatment effects in one language can automatically carry over to the other language, it is unclear whether these findings are influenced by factors such as language dominance or language structure. These issues need to be clarified because speech language pathologists (SLPs) who work with bilinguals often do not speak the dominant language of their clients. Thus, the language of assessment and treatment becomes an important clinical consideration. The aim of this thesis was to investigate (a) whether the severity and type of stuttering was different in English and Mandarin in English-Mandarin bilingual adults, (b) whether this difference was influenced by language dominance, (c) whether stuttering reductions in English generalized to Mandarin following treatment in English only, and (d) whether treatment generalization was influenced by language dominance. To achieve these aims, a way of establishing the dominant language in bilinguals was a necessary first step. The first part of this thesis reviews the disorder of stuttering and the treatment for adults who stutter, the differences between English and Chinese languages, and stuttering in bilinguals. Part Two of this thesis describes the development of a tool for determining language dominance in a multilingual Asian population such as that found in Singapore. This study reviews the complex issues involved in assessing language dominance. It presents the rationale for and description of a self-report classification tool for identifying the dominant language in English-Mandarin bilingual Singaporeans. The decision regarding language dominance was based on a predetermined set of criteria using self-report questionnaire data on language proficiency, frequency of language use, and domain of language use. The tool was administered to 168 English-Mandarin bilingual participants, and the self-report data were validated against the results of a discriminant analysis. The discriminant analysis revealed a reliable three-way classification into English-dominant, Mandarin-dominant, and balanced bilinguals. Scores on a single word receptive vocabulary test supported these dominance classifications. Part Three of this thesis contains two studies investigating stuttering in BWS. The second study of this thesis examined the influence of language dominance on the manifestation of stuttering in English-Mandarin BWS. Results are presented for 30 English-Mandarin BWS who were divided according to their bilingual classification group: 15 English-dominant, four Mandarin-dominant, and 11 balanced bilinguals. All participants underwent comprehensive speech evaluations in both languages. The English-dominant and Mandarin-dominant BWS were found to exhibit greater stuttering in their less dominant language, whereas the balanced bilinguals evidenced similar levels of stuttering in both languages. An analysis of the types of stutter using the Lidcombe Behavioral Data Language showed no significant differences between English and Mandarin for all bilingual groups. In the third study of this thesis, the influence of language dominance on the generalization of stuttering reductions from English to Mandarin was investigated. Results are provided for seven English-dominant, three Mandarin-dominant, and four balanced bilinguals who underwent a Smooth Speech intensive program in English only. A comparison of stuttering between their pretreatment scores and three posttreatment interval scores indicated that the degree of fluency transfer from the treated to the untreated language was disproportionate. English-dominant and Mandarin-dominant participants showed greater fluency improvement in their dominant language even if this language was not directly treated. In the final chapter, Part Four, a hypothesis is provided to explain the findings of this thesis. A discussion of the limitations of the thesis and suggestions for future research are also presented. The chapter concludes with a summary of the main contributions that this thesis makes to the field of stuttering in bilinguals.

El llenguado senegalès (Solea senegalensis) és una espècie aqüícola emergent a Europa. No obstant això, el llenguado senegalès presenta una falla reproductiva, que es tradueix en la manca de reproducció fèrtil dels reproductors que van ser eclosionados i criats en captivitat. Tot i que els reproductors conreats produeixen gàmetes viables, la disfunció provoca la pèrdua de comportament reproductiu i de festeig en mascles cultivats i, per tant, els ous alliberats per les femelles no són fecundats. Actualment, la producció d'ous viables obté de criadors salvatges en captivitat, però la producció exclusiva d'ous de criadors salvatges no és sostenible a llarg termini. A més, l'anàlisi parental de les larves eclosionades dels criadors salvatges ha determinat que pocs criadors salvatges participen en la cria, el que va provocar una pèrdua de variabilitat genètica en les generacions posteriors. Per solucionar aquest problema hi ha dos enfocaments: aconseguir la cria espontània natural a criadors de cultiu com una solució a la disfunció comportamental en els mascles de cultiu o l'ús de fecundació artificial per evitar la disfunció conductual. Per tant, la present tesi s'ha centrat en: a) experiments per resoldre la disfunció en el comportament reproductiu dels criadors conreats, b) la influència de l'comportament de dominància en l'èxit reproductiu, c) mètodes per preservar la qualitat de l'esperma necessària per assolir l'èxit in vitro en els procediments de fecundació de l'llenguado senegalès i el peix llop clapejat (Anarhichas minor) id) determinar la proporció esperma-òvuls necessària per a la fecundació in vitro en llenguado senegalès.
El lenguado senegalés (Solea senegalensis) es una especie acuícola emergente en Europa. Sin embargo, el lenguado senegalés presenta una falla reproductiva, que se traduce en la falta de reproducción fértil de los reproductores que fueron eclosionados y criados en cautividad. Aunque los reproductores cultivados producen gametos viables, la disfunción provoca la pérdida de comportamiento reproductivo y de cortejo en machos cultivados y, por tanto, los huevos liberados por las hembras no son fecundados. Actualmente, la producción de huevos viables se obtiene de criadores salvajes en cautividad, pero la producción exclusiva de huevos de criadores salvajes no es sostenible a largo plazo. Además, el análisis parental de las larvas eclosionadas de los criadores salvajes ha determinado que pocos criadores salvajes participan en la cría, lo que provocó una pérdida de variabilidad genética en las generaciones posteriores. Para solucionar este problema hay dos enfoques: conseguir la cría espontánea natural a criadores de cultivo como una solución a la disfunción comportamental en los machos de cultivo o el uso de fecundación artificial para evitar la disfunción conductual. Por tanto, la presente tesis se ha centrado en: a) experimentos para resolver la disfunción en el comportamiento reproductivo de los criadores cultivados, b) la influencia del comportamiento de dominancia en el éxito reproductivo, c) métodos para preservar la calidad del esperma necesaria para alcanzar el éxito in vitro en los procedimientos de fecundación del lenguado senegalés y el pez lobo moteado (Anarhichas minor) y d) determinar la proporción esperma-óvulos necesaria para la fecundación in vitro en lenguado senegalés.
The Senegalese sole (Solea senegalensis) is an emerging aquaculture species in Europe. However, in captivity Senegalese sole present a reproductive failure, which results in the lack of fertile spawning from cultured breeders that were hatched and reared in captivity. Although the cultured breeders produce viable gametes, the dysfunction causes the loss of reproductive behaviour or courtship in cultured males and, therefore, the eggs released by females are not fertilized. However, viable egg production is obtained from wild breeders held in captivity, but the exclusive production of eggs from wild breeders is not sustainable in the long term. In addition, parental analysis of hatched larvae from wild breeders has determined that few wild breeders participate in spawning, which resulted in a loss of genetic variability in subsequent generations. Two approaches exist to solve this bottleneck: achieving natural spontaneous spawning in cultured breeders with a solution to the behavioural dysfunction in cultured males or the use of artificial fertilization to bypass the behavioural dysfunction. Therefore, the present thesis has been focused on: a) experiments to solve the dysfunction in the reproductive behaviour of cultured breeders, b) the influence of dominance behaviour on reproductive success, c) methods to preserve the sperm quality needed to achieve successful in vitro fertilisation procedures in Senegalese sole and Spotted wolffish (Anarhichas minor) and d) determine the sperm to egg ratio require for in vitro fertilisation in Senegalese sole.

Many canids live within hierarchical social systems that could promote differences in learning or in behavior between ranked individuals. Differences in foraging and territorial behavior have been observed between ranked coyotes (Canis latrans), yet effects of learning and social status on coyote behavior are not thoroughly understood. I explored a) coyote response to an artificial scent boundary and whether response differed by status, b) how foraging coyotes tracked temporal resource change, and c) how coyotes find spatially distributed food, and the effect of dominance on foraging behavior. I used male/female pairs of captive coyotes at the National Wildlife Research Center Predator Research Facility in Utah. Prior to testing, I identified social rank within pairs by testing for food dominance. In study 1, I laid a scent boundary and monitored space use with GPS and observed behavioral responses directly. All coyotes investigated and crossed the boundary, but were repelled more by human presence. Subordinates investigated and marked the boundary more than dominants. Further investigation is needed to mimic natural boundaries for management purposes. In study 2, I gave eight individual coyotes an operant test with concurrent variable interval (VI) schedules. I varied the ratio of resources and measured the time spent on two choices, then fitted the generalized matching equation to the data. I found that all coyotes efficiently tracked changes in resource ratios and matched their relative rate of foraging time to relative rate of resources. Matching theory provides an effective methodology to explore foraging strategies and behavioral flexibility in coyotes. In study 3, I tested 16 coyotes in a spatial foraging task. Coyotes searched for food in eight potential locations, and were tested individually and in respective pairs. I recorded the area and number of locations searched, approach time, and frequency of marking by dominant and subordinate coyotes. Results showed individual subordinates increased efficiency by relocating, but their efficiency decreased when foraging in pairs. Dominant coyotes did not increase efficiency in company by following subordinates. Coyotes marked the correct feeder more than incorrect feeders. Results suggest coyotes use memory and odor (scent marks) to find food, but that social status overrules information use.

Dominance rank often determines the share of reproduction an individual male can secure in group-living animals (i.e. dominance rank-based reproductive skew). However, our knowledge of the interplay between individual and social factors in determining rank trajectories of males is still limited. The overall aim of this thesis was therefore to investigate mechanisms that underlie individual dominance rank trajectories in male crested macaques (Macaca nigra) and to highlight potential individual and social determinants of how males can achieve and maintain the highest rank possible. Data for this thesis were collected on 37 males during a field study on a natural population of crested macaques living in the Tangkoko-Batuangus Nature Reserve in Indonesia. In study 1, I validate Elo-rating as a particularly well suited method to quantify dominance hierarchies in animal species with dynamic dominance relationships. In studies 2 and 3, I suggest a personality structure for crested macaque males consisting of five distinct factors and further demonstrate that two personality factors determine whether males will rise or fall in rank. Finally, in study 4, I present results on how males utilize coalitions to increase their future rank. Together, these results shed light on how individual attributes and social environment both can impact male careers. Ultimately, in order to understand what determines rank-based reproductive skew, we need to consider the complexity and likely diversity of the mechanisms underlying rank trajectories of individual males which are likely to differ across different species.

Variation of gene expression in the brain may play a critical role in determining behavioural phenotypes. Grb10 gene is an imprinted gene expressed from embryonic stages into adulthood. In mice, Grb10 parental alleles are expressed in a tissue-specific manner, with the expression of the maternal allele in the placental trophoblasts and most embryonic tissues. The paternal allele is expressed in certain regions of the brain. Grb10 expression in the adult is limited to few tissues with the maternal allele expressed in muscle tissues and the paternal copy maintains its expression in the midbrain. While maternal knockdown of Grb10 is associated with foetal growth, a function shared with several other imprinted genes, knocking down of the paternal allele mice is associated with increased social dominance. The interactors of Grb10 in the brain, however, are not yet known. In this project, I aimed to uncover the potential molecular interactors mediating Grb10’s function in the brain. For this, I obtained whole genome transcriptional profiles using Illumina RNA-Seq technology for the midbrain where paternally inherited Grb10 is expressed in adult stages and the neocortex where Grb10 is not expressed for mutantGrb10KO+/p and wild-type. Using differential gene expression analyses, I identified a set of genes altered in the paternal mutant Grb10KO+/p. I further examined how these sets of genes change over time by examining samples taken at different developmental stages. Gene expression profile changes in the Grb10KO in the brain are distinct from gene expression changes in the liver suggesting that the maternal and paternal alleles are associated with different sets of genes in different tissues. Co-expression analyses revealed significant shifts in gene to gene relationships in the KO context. Together, my results provide insights into the molecular interactors of Grb10 in the brain and may give clues as to how Grb10 influences social dominance.

Nonverbal communication in leadership is a phenomenon which is interesting to get a greater understanding of. Animals only communicate nonverbally and have strong leadership behaviours. Therefore, this study aim is to find out in what way nonverbal communication in leaders is still connected to animal roots and what the implications for modern life are. This study tries to give an overview of the phenomenon with a theoretical approach. Different point of views of nonverbal communication and animal behaviour in leaders have been discussed. A theoretical approach was suitable because of the abundance of literature in the main fields of focus. Connecting the different studies with each other gave valuable insights into the phenomenon. Power, status, submission, territory, space, and mating behaviours are the most used categories associated with leadership behaviours in animal species. Human leadership behaviour consists of the same categories but furthermore, emotional intelligence is an integral part as well. Different postures, gestures, facial expressions as well as distances to each other gave a comprehensive overview of how leaders are naturally behaving. Deciphering the complex nonverbal communication and looking at them with aspects of communication in animals helped with showing the roots and the natural ability to lead. Further research, however, should be conducted to see how nonverbal communication influences complex group dynamics and the effect thereof. Implications for the natural instincts to lead are helpful with how leaders can further their communication skills and become more conscious of their nonverbal communication.

The objectives of this study were to determine the effects of handling peri-puberal heifers for 2 h each week on in-chute behavior, isolation behavior, and the time required for each heifer to leave the testing area; and to determine if the location of the facial hair whorl was associated with any of the behavior scores or social dominance order. Crossbred beef heifers (n = 146) were assigned to be walked through, sorted and moved through a chute for 2 hr each wk for 20 wk (HANDLED) or allowed to remain on pasture unless handling was required to treat an injury or disease (CONTROL). In-chute behavior, isolation behavior and exit times were observed and scored at the beginning (0 wk), middle (10 wk) and end of the experiment (20 wk). The facial hair whorl on each heifer was classified as being high (above the eyes), middle (between the eyes), or low (below the eyes). At the end of the experiment pairs of heifers in the HANDLED group competed for a feed source and a social dominance order was estimated. Weekly handling decreased in-chute behavior scores of heifers with facial hair whorl positions classified as medium or low, but not in heifers that exhibited a hair whorl high on their face. Cattle in the HANDLED treatment group which had an initial isolation score of 2 or 3 had the greatest improvement in temperament over the entire experiment when compared to CONTROL animals with the same initial isolation score. The calmest heifers were not negatively affected by the handling, while the most agitated animals in the HANDLED had a similar overall change in isolation score as those animals in the CONTROL group. This indicates that while weekly handling improved the temperament and behavior of heifers with intermediate temperament rating at the outset of the experiment, weekly handling seemed unnecessary for the calmest heifers and did not have a beneficial effect on the heifers rated as the most nervous and agitated at the beginning of the experiment. Social dominance rankings were positively correlated (P < 0.10) with final in-chute behavior scores, but not with the other behavior scores or heifer body weight. Cattle with the hair whorls in the middle of the forehead had higher mean social dominant rank than those with hair whorls higher or lower on the face (P < 0.03). Overall, the results of this experiment indicate that behavior testing can reveal differences in the temperament of heifers and that, other than the most nervous and agitated heifers; repeated handling could serve to improve the temperament of the animals.
Master of Science

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The analysis of the index of hierarchy and structural models of the formation of groups allowed to establish the hierarchical position of members of two groups of the genus Cebus. By the analyses of the hierarchical positions and the application of tests to obtain a food resource (TORA), we know the difference between these groups and groups in the wild. The results show a high ranking for both Cebus apella, as well as Cebus libidinosus. The results have enabled us to establish that the hierarchical structure in groups of Cebus in captivity: a) can be fixed and rigid different from highly flexible hierarchical structure studied in groups of wild b) even which similar hierarchy indices, there are differences in the hierarchical structure presents between C. apella and C. libidinosus in captivity c) hierarchy directly influence the behavioral patterns of obtaining food in Cebus
A an?lise do ?ndice de hierarquia e modelos estruturais de forma??o de grupos possibilitou estabelecer a posi??o hier?rquica dos membros de dois grupos do g?nero Cebus. Atrav?s da an?lise das posi??es hier?rquicas e tamb?m da aplica??o de testes de obten??o de recurso alimentar (TORA), pudemos perceber a diferen?a existente entre estes grupos e grupos estudados em vida livre. Os resultados mostram linearidade tanto para Cebus apella, quanto para Cebus libidinosus. Os resultados nos permitiram estabelecer que a estrutura hier?rquica em grupos de Cebus em cativeiro: a) pode ser r?gida e fixa diferente da estrutura hier?rquica altamente flex?vel estudada em grupos de vida livre; b) mesmo com ?ndices similares de hierarquia, existem diferen?as na estrutura hier?rquica apresenta entre C. apella e C. libidinosus em cativeiro; c) hierarquia influencia diretamente os padr?es comportamentais de obten??o de alimentos em Cebus

Balance of motor network activity between the two brain hemispheres after stroke is crucial for functional recovery. Several studies have extensively studied the role of the affected brain hemisphere to better understand changes in motor network activity following stroke. Very few studies have examined the role of the unaffected brain hemisphere and confirmed the testretest reliability of connectivity measures on unaffected hemisphere. We recorded blood oxygenation level dependent functional magnetic resonance imaging (fMRI) signals from nine stroke survivors with hemiparesis of the left or right hand. Participants performed a motor execution task with affected hand, unaffected hand, and both hands simultaneously. Participants returned for a repeat fMRI scan 1 week later. Using dynamic causal modeling (DCM), we evaluated effective connectivity among three motor areas: the primary motor area (M1), the premotor cortex (PMC) and the supplementary motor area for the affected and unaffected hemispheres separately. Five participants manual motor ability was assessed by Fugl-Meyer Motor Assessment scores and root-mean square error of participants tracking ability during a robot-assisted game. We found (i) that the task performance with the affected hand resulted in strengthening of the connectivity pattern for unaffected hemisphere, (ii) an identical network of the unaffected hemisphere when participants performed the task with their unaffected hand, and (iii) the pattern of directional connectivity observed in the affected hemisphere was identical for tasks using the affected hand only or both hands. Furthermore, paired t-test comparison found no significant differences in connectivity strength for any path when compared with one-week follow-up. Brain-behavior linear correlation analysis showed that the connectivity patterns in the unaffected hemisphere more accurately reflected the behavioral conditions than the connectivity patterns in the affected hemisphere. Above findings enrich our knowledge of unaffected brain hemisphere following stroke, which further strengthens our neurobiological understanding of stroke-affected brain and can help to effectively identify and apply stroke-treatments.

The thesis aimed to explore the experience of sibling aggression. Previous research has focused on the prevalence, predictors and effects of siblings engaging in aggressive behaviours with one another. However, there is a distinct lack of evidence that has explored the experience of this form of family violence. The thesis made an original contribution to knowledge by exploring the impact of multiple forms of family violence on the use of aggression between siblings, asking victims and/or perpetrators of these aggressive behaviours about their retrospective experiences and developing a quantitative measure of sibling aggression. A mixed methods approach was taken, employing archival, qualitative and quantitative techniques. More specifically, an archival study of the 1975 National Family Violence Survey (NFVS; Straus, Gelles & Steinmetz, 1980) was conducted to explore the relationship between co-occurring aggression and sibling aggression. The findings revealed that as co-occurring verbal or physical aggression increased within the family environment, the frequency of both physical and verbal aggression between siblings also increased. Following this, semi-structured interviews were conducted with victims and/or perpetrators of sibling aggression to explore this form of family violence further, particularly in relation to how aggression differs from play fighting, and the role of normalisation. The interviews identified that although aggressive acts of behaviour may look similar to those for play fighting, the motivations and functions of them differ. More specifically, play fighting was an enjoyable and game-like behaviour for children, whereas sibling aggression often occurred in response to a build-up of negative emotions, to maintain dominance or to overcome verbal arguments. The normalisation of sibling aggression was also important, particularly in relation to how parents responded to their children using aggressive behaviours with one another. In the third study of this thesis, a questionnaire, the Experiences of Sibling Aggression (ESA) scale, was developed to not only test the themes derived from the interviews on a larger scale, but to also explore differences between victims and perpetrators of this form of family violence. Amongst a sample of participants recruited through social media and on a university campus, a four-factor model of the ESA scale was validated, with subscales that reflected; play fighting, sibling aggression, normalisation and dominance. The ESA scale was also shown to increase the likelihood of predicting mutual sibling aggression, with these participants scoring higher on the sibling aggression subscale (concerning the use of aggression to overcome negative emotions and solve arguments) when compared to a control group of participants who had no previous involvement in aggression with their sibling. These studies have provided several key contributions to knowledge of sibling aggression. Firstly, they have highlighted the relationship between sibling aggression and multiple forms of family violence. Secondly, they have enhanced the understanding of how play fighting and sibling aggression are conceptualised and differ from one another, highlighting the importance of parents in intervening in these behaviours. Finally, the ESA scale was developed, specifically for the exploration of this form of family violence. The implications of the findings involve the need to consider contextual factors rather than only the individual acts of aggression between siblings. It can be concluded that sibling aggression is a serious form of family violence serving a different function when compared to play fighting among children. This should be reflected in both practice and future research.

Thyroid hormones are well known important to be in development and growth in birds and that signaling of thyrotropin (TSH) regulates the photo induced seasonal reproduction. A mutation at the thyroid stimulating hormone receptor (TSHR) gene in domestic breeds of chicken could be involved in the release of the photoperiodic regulation. Furthermore, TSH can affect a wide range of domestication related phenotypes, such as behaviour, growth rate and pigmentation. The aim of this study was to investigate the behaviours expressed in the different genotypes on the TSHR gene in chickens. Four standard tests were conducted, aerial predator, fear of human, social dominance and tonic immobility. An advanced intercross line of chickens between red junglefowl and White leghorn was used. Male domestic type chickens explored more, showed more less fear behaviours and showed least fear behaviours in the fear of human test. Increased activity and flight response has been interpreted as a lower fear response, which is in line with this study. The wild type chickens showed more social dominance than domestic type chickens which are in line with previous results. In tonic immobility there was a difference between the wild type male and heterozygous male chickens in latency until first head movement. The conclusion of this study is that there is a difference between the wild type and domestic type chickens. This indicates that the TSHR gene is involved in behavioural changes during domestication, but whether it is due to passive or active selection is the question.

Adaptation to changing social conditions is important for many social animals. Here, the effects of social experience on the behavior and neurophysiology of the red swamp crayfish, Procambarus clarkii, were studied. Evidence is presented that shows juvenile crayfish interact and form social order, and their behavior patterns shift in accordance to social status. Dominant animals maintain a high level of aggressive behavior, while subordinates shift their behavior pattern from aggressive to submissive behavior. Adult male crayfish show similar behavior pattern during dominance formation. However, this work demonstrates that male crayfish adopt a unique strategy to signify the formation of a social order expressed in the form of pseudocopulation. Pseudocopulation between male crayfish signifies the acceptance of the social status and leads to the reduction of aggression of dominants and enhances the survival of subordinate animals. I investigated the long-term effects of social status on the behavioral and physiological responses of crayfish to unexpected sensory touch. I discovered that animals of different social experience display different orienting responses that correlate with in vivo electromyographic recordings from the legs’ depressor muscle. The status-dependent response patterns observed in vivo are retained in a reduced, in vitro, preparation that lacks descending input from the brain. The role of serotonin (5-HT) was investigated in mediating the motor output patterns of the depressor nerve. Putative serotonergic innervations of the depressor nerve were identified that originate from serotonergic neurons located in the first abdominal ganglion. Selective stimulation of the ipsilateral 5-HT neuron enhances the response of the depressor nerve to sensory stimulation. Application of 5-HT modestly increased the tonic firing activity of the depressor nerve in social isolates and subordinates but significantly decreased the activity in dominants. This work illustrates that the formation of a dominance relationship significantly and immediately alters the behavior of the participants. As the social relationship matures, the social experience that develops affects the underlying neurophysiology that mediates the behavior. It will be of great interest in future studies to identify not only the effects rather the mechanisms of how social experience induces physiological changes.

This study identified factors and variables of informal leadership in small groups with different gender composition (Men, women and mixed groups) and goal orientation (competition and cooperation). Behavioral dominance patterns (Information Sheet, pencil, decision sheet) and number of verbal interventions were compared to the main informal leadership factors identified in the groups. There were 24 participants (12 men and 12 women). Among the main variables and factors identified, there were some that had a higher possibility to appear than other. There was no significant difference of the factors and variables between women and men. Communication variables were more likely to be present in groups with the goal of cooperation as for the goal of competition. Guidance variables were more likely to be present in women groups than in men groups and mixed groups. There was a significant correlation between the factor’s Communication, Character and Guidance with the number of interventions and behavioral dominance patterns.

The earth’s climate is rapidly changing. With climate change currently altering the environment, water temperature is an important environmental factor that will have various effects on fishes since they are ectotherms. As the changes are expected to be greatest during winter, when salmonid fishes incubate their eggs, one might expect substantial effects on egg development. In this experiment pairs of fish, matched by length, were compared. For each pair, one fish had experienced ambient cold temperatures (cold treatment) during embryogenesis and the other elevated temperatures (warm treatment, ca. 4-5 oC). The fish were tested in stream. Aggressive interactions were recorded and dominance was determined by scoring each fish’s position relative to where food was delivered from and the amount of food taken. Salmon from the cold treatment had a strong tendency to have a higher dominance score than salmon from the warm treatment. The individual with the highest dominance score was not consistently larger or smaller than the individual with the lower dominance score. The results support the hypothesis that salmonids exposed to a cold environment during embryogenesis will be more dominant. Due to climate change, it is expected that water temperature will continue to rise in the future, which in turn will alter the fish’s behaviour.
Jordens klimat förändras snabbt. Med klimatförändringar som för närvarande förändrar miljön är vattentemperaturen en viktig miljöfaktor som kommer att ha olika effekter på fiskar eftersom de är ektoterma. Eftersom förändringarna förväntas vara störst under vintern, när laxfiskar inkuberar sina ägg, kan man förvänta sig betydande effekter på äggutvecklingen. I det här experimentet jämfördes fisk par, matchade med längd. För varje par hade en fisk upplevt kalla vattentemperaturer (kall behandling) under embryogenesen och de andra förhöjda temperaturerna (varm behandling, ca 4-5 oC). Fisken testades i strömakvarie. Aggressiva interaktioner registrerades och dominans bestämdes genom att poängsätta varje fisks position i förhållande till var mat levererades från och mängden mat som tagits. Lax från den kalla behandlingen hade en stark tendens att ha högre dominanspoäng än lax från den varma behandlingen. Individen med högsta dominanspoäng var inte konsekvent större eller mindre än individen med lägre dominanspoäng. Resultaten stöder hypotesen att salmonider utsätts för en kall miljö under embryogenes kommer att vara den mer dominerande. På grund av klimatförändringen är det förväntat att vattentemperaturen fortsätter att stiga i framtiden, vilket i sin tur kommer att förändra fiskens beteende.