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Title: The relationship between color change and social behavior in the green sunfish, lepomis cyanellus (raf.)
Creator: Fabry, Diane Merle Prater, 1938-
Date: 1972
Collection: Electronic Theses & Dissertations

Title: Social interactions between confined juvenile and adult P̲e̲r̲o̲m̲y̲s̲c̲u̲s̲ m̲a̲n̲i̲c̲u̲l̲a̲t̲u̲s̲ b̲a̲i̲r̲d̲i̲ : effects of social factors on juvenile settlement and growth
Creator: Enders, John E., 1948-
Date: 1977
Collection: Electronic Theses & Dissertations

Title: The effects of varied feed bunk space on animal production and behavior, management strategy, and building design
Creator: Stephenson, Mark William
Date: 1980
Collection: Electronic Theses & Dissertations

Title: Social behavior of the aoudad (Ammotragus lervia) in Hondo Valley, New Mexico
Creator: Habibi, Khushal
Date: 1983
Collection: Electronic Theses & Dissertations

Title: Cooperation, competition and kinship in the social relationships among spotted hyenas, Crocuta crocuta
Creator: Wahaj, Sofia Anne
Date: 2004
Collection: Electronic Theses & Dissertations

Title: Social recognition in neonatal pigs and the effects of acute stressors on it
Creator: Souza, Adriana Silveira de
Date: 2006
Collection: Electronic Theses & Dissertations

Title: The spatial and social organization of forest buffalo (Synerus caffer nanus) at Lope National Park, Gabon
Creator: Korte, Lisa Marie
Date: 2007
Collection: Electronic Theses & Dissertations

Title: Evolutionary and ecological forces shaping patterns of cooperation among spotted hyenas
Creator: Smith, Jennifer Elaine
Date: 2010
Collection: Electronic Theses & Dissertations

Title: Variation among free-living spotted hyenas in three personality traits
Creator: Shaw, Kathryn Cushing
Date: 2012
Collection: Electronic Theses & Dissertations
Description: Inter-individual differences in behavior, termed "animal personality," are often consistent over time and across contexts, and can be significantly related to fitness. Most studies of animal personality are conducted in the laboratory on captive animals or with experimental protocols on wild animals; few studies have used observational data from free-living animals to examine personality. In this dissertation, I use longitudinal data collected under naturalistic conditions to study...
Show moreInter-individual differences in behavior, termed "animal personality," are often consistent over time and across contexts, and can be significantly related to fitness. Most studies of animal personality are conducted in the laboratory on captive animals or with experimental protocols on wild animals; few studies have used observational data from free-living animals to examine personality. In this dissertation, I use longitudinal data collected under naturalistic conditions to study personality in a wild population of spotted hyenas (Crocuta crocuta). This study is the first to examine the stability, the proximate causes, and the fitness implications of consistent inter-individual differences in a large, free-living carnivore. I investigated three personality traits that are particularly pertinent to survival and reproduction in spotted hyenas: boldness, aggressiveness, and sociability. Lions are a major source of mortality for hyenas, yet hyenas regularly interact with them directly due to the potential benefits of acquiring food. Because hyenas must balance the risk of injury or death with the benefits of resource acquisition, lion-hyena interactions offer a promising way to study boldness. Aggression is frequent and easily observable in hyenas; moreover, it is tightly coupled with access to food, which is a major determinant of reproductive success in this species. Finally, hyenas vary in their propensity to engage in social behavior with conspecifics, and sociability has been shown to affect fitness in species with societies that are remarkably similar in size and structure to those of spotted hyenas. I found significant differences among individual hyenas in all three traits. However, whereas both sexes exhibited consistent inter-individual differences in aggressiveness and sociability, males were less consistent than females in their boldness; this may be due to their low social status and reduced access to resources. Attributes of the individual (e.g. social rank) and situational factors (e.g. seasonal prey availability) affected all three personality traits. Heritability and maternal effects were significant, but small, for both boldness and sociability. A much larger proportion of the variation in aggressiveness could be attributed to genetic and maternal effects, supporting previous research linking hormone exposure in utero to aggressive behavior later in life. Whereas both boldness and aggressiveness were stable across age classes, sociability changed across ontogeny and the nature of this change varied with social rank; at reproductive maturity, low- but not high-ranking hyenas became more likely to greet with conspecifics. The advantages of associating with dominant hyenas, such as increased feeding tolerance, may be especially important for low-ranking individuals. Interestingly, the fitness benefits of sociability and aggression also varied with rank; high rates of aggression and sociability enhanced the reproductive success of low-ranking hyenas more than that of high-ranking hyenas. Dominant hyenas have priority of access to resources, and may not obtain additional reproductive benefits from these personality traits. However, for low-ranking hyenas, gaining feeding tolerance via sociability or increasing resource-holding potential via aggressiveness may significantly enhance reproductive success.Both boldness and sociability were linked to survival, but these traits affected longevity in different ways. Highly social hyenas lived longer than those that were less social; meanwhile, selection on boldness was stabilizing, favoring hyenas with intermediate boldness values that struck a balance between reaping the benefits of risky behavior and minimizing the risks of injury and death.
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Title: Competition and cooperation among males in a sex-role reversed mammal, the spotted hyena (Crocuta crocuta)
Creator: Curren, Leslie J.
Date: 2012
Collection: Electronic Theses & Dissertations
Description: Sexual selection theory predicts that when females have the limiting reproductive rate, males should compete for access to those females via one of several mechanisms, such as male–male combat, sperm competition, or endurance rivalry. In this dissertation, I investigated the nature of intrasexual male competition in a sex role–reversed species, the spotted hyena (Crocuta crocuta), by examining each of those mechanisms. First, I tested hypotheses regarding the...
Show moreSexual selection theory predicts that when females have the limiting reproductive rate, males should compete for access to those females via one of several mechanisms, such as male–male combat, sperm competition, or endurance rivalry. In this dissertation, I investigated the nature of intrasexual male competition in a sex role–reversed species, the spotted hyena (Crocuta crocuta), by examining each of those mechanisms. First, I tested hypotheses regarding the function of male–male combat. In most mammals, male–male combat functions to provide immediate access to females, but in spotted hyenas, females have complete control over copulation, so the benefits of intrasexual male aggression are less obvious. The results suggested that although males cannot control copulation, they use aggression to influence clan membership by restricting male immigration, which in turn affects their likelihood of siring cubs. The data likewise suggested that male aggression functions to provide access to food during competition with other males. Second, I took steps toward elucidating the importance of sperm competition in this species by describing ejaculate quality in wild male spotted hyenas and demonstrating temporal repeatability within individuals. Additionally, I found that immigrant males had significantly higher quality ejaculates than adult natal males, suggesting that adult natal males might experience reproductive suppression prior to dispersing. Third, I explored the notion that male spotted hyenas compete via an endurance rivalry by examining the relationship between tenure in the clan and annual reproductive success, and then investigated additional factors that might influence the outcome of this contest. The results indicated that immigrant males do indeed compete via an endurance rivalry, and for an immigrant to compete most effectively, he must remain in the clan and associate closely with females. However, pieces remain missing from the puzzle of male reproductive success in this species, because I found a striking quadratic effect of tenure on annual reproductive success, and the eventual decline in reproductive success remains unexplained. Finally, in addition to investigating male competition, I asked what evolutionary forces promote cooperative behavior among males. Kin selection and reciprocal altruism appeared to play no role in male–male cooperation; rather, males appeared to cooperate with one another to receive a variety of direct benefits. Overall, these results help illuminate the selective forces shaping competition and cooperation among males in a role–reversed species, and suggest how these forces might influence a male's reproductive output.
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Title: Androgen and serotonin concentrations in spotted hyenas (Crocuta crocuta : physiological predictors and relationships with the social environment
Creator: Jones, Sarah Christine
Date: 2019
Collection: Electronic Theses & Dissertations
Description: Animals display a wide range of social behaviors, including social behaviors such as aggression, mating, and parental care. An individual's ability to express the 'right' behavior in the appropriate context is vital to its success. For instance, individuals should engage in mating behavior during the appropriate life history stage (i.e. age, season) and avoid it in inappropriate contexts, such as in the presence of a predator. Neuroendocrine systems are key in allowing individuals to match...
Show moreAnimals display a wide range of social behaviors, including social behaviors such as aggression, mating, and parental care. An individual's ability to express the 'right' behavior in the appropriate context is vital to its success. For instance, individuals should engage in mating behavior during the appropriate life history stage (i.e. age, season) and avoid it in inappropriate contexts, such as in the presence of a predator. Neuroendocrine systems are key in allowing individuals to match their behavior to their current situation, as these systems affect behavior and are also responsive to changes in the environment and in an organism's internal state.Serotonin, a neuromodulator, and androgenic sex steroid hormones are key regulators of aggression and appear to play a central role in matching an organism's aggressive behavior to its social environment. For instance, in many social species living in dominance hierarchies, an individual's social status affects concentrations of serotonin and androgens. Serotonin is a known inhibitor of aggression, whereas androgens often facilitate the expression of aggression; accordingly, social dominance is often negatively correlated with serotonin concentrations and positively correlated with androgens. Still, these patterns are not universal, varying with sex, species, life history stage, and social context.Here, I examined the physiological, demographic, and environmental correlates of serotonin and androgens in a despotic, female-dominant species-the spotted hyena. Specifically, I focused on the relationship between social rank and serotonin/androgens, and its modulators. I first examined predictors of two androgens, testosterone (T) and androstenedione (A4), in pregnant female hyenas. I found a positive relationship between both androgens and social rank. However, this relationship was specific to pregnant females who had previously given birth (multiparous), apparently due to an increase in maternal androgens in high-ranking but not low-ranking females after the birth of their first litter.I then examined the relationship between T and social status in adult females across different reproductive states and social contexts, I found a positive correlation between T and social status in lactating and pregnant females, but not in nulliparous females; again, this pattern appeared to be driven by an increase in high-ranking female T concentrations associated with their first breeding experience. In a comparison of T concentrations in lactating females during periods of relative social stability and instability, I found that T concentrations in low- but not high- ranking females increased during periods of social instability, resulting in the disappearance of the usual positive correlation between social rank and T.Finally, I examined predictors of serotonin concentrations in both male and female hyenas across ontogeny. Serotonin was negatively correlated with social rank in female but not male spotted hyenas. Furthermore, social status at birth was particularly predictive of serotonin, as opposed to social status at the time of physiological sampling, indicating early life social environment may have lifelong effects on serotonergic function.Overall, I found that social status was an important predictor of androgen and serotonin concentrations, but that this relationship was dependent upon characteristics of the individual (e.g. sex, life history stage) and their social environment.
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Title: Individual behavior types and social cohesion of group-housed pigs
Creator: O'Malley, Carly I.
Date: 2019
Collection: Electronic Theses & Dissertations
Description: "Group-housing of pigs can provide benefits for pig welfare, such as interaction with conspecifics and the ability to perform more natural behaviors. Unfortunately, group-housing also presents major welfare concerns. Pigs are often mixed at different production stages based on sex and weight in order to create uniform groups that allow for more efficient resource use by producers. Unfortunately, when unfamiliar pigs are introduced this causes intense aggression as pigs establish a social...
Show more"Group-housing of pigs can provide benefits for pig welfare, such as interaction with conspecifics and the ability to perform more natural behaviors. Unfortunately, group-housing also presents major welfare concerns. Pigs are often mixed at different production stages based on sex and weight in order to create uniform groups that allow for more efficient resource use by producers. Unfortunately, when unfamiliar pigs are introduced this causes intense aggression as pigs establish a social hierarchy. This increased aggression can persist for 24--48 h after a mixing event and can lead to injury, infection, and stress. Pigs are highly social animals, and as such, have individual differences in behavior and complex social relationships that need to be considered when addressing social aggression. The long-term goals of this project were to identify individual behavior types and understand the role of individual behavior types in social behavior in group-housed pigs. The specific objectives for this research were to understand the role of personality in the management and welfare of pigs through a comprehensive literature search, to identify individual behavior types in group-housed pigs using individual time budgets and behavior tests, and to explore measures of social cohesion in recently mixed pigs as they form a stable social group. Many studies have investigated the role of personality in the management of pigs but as a new field of study there are a number of issues that prevent the advancement of this field into behavioral management of livestock. Despite that, pig personality traits have been related to factors related to pig physiology, housing environment, social behavior, and cognition and therefore there is potential for producers to incorporate pig personality information into their breeding, care, and welfare. Individual pigs vary in their overall behavior, therefore part of this research aimed to compare pig time budgets with duration of aggression at different time points. It was found that pig behavior varies immediately after mix and becomes more consistent at 6 wk after mixing. The amount of time pigs spend on non-aggressive behaviors was related to aggression, particularly time spent inactive and exploring. We also compared duration of aggression with production traits of growth rate, backfat thickness, and loin muscle area. Pigs that are more aggressive at mix and at 3 wk after had slower growth and smaller loin muscle area, suggesting that efforts to reduce aggression should be implemented not only after mixing, but in the weeks following to prevent negative consequences on production traits. One solution to address the issue of aggression is to breed for less aggressive pigs without inadvertently disrupting other behavior traits important in managing pigs. Behavior tests were used to assess traits of fearfulness and response to humans, and these measures were compared with lesion scores, a proxy measure of aggressiveness. Aggressiveness was related to pigs' responses in social and non-social challenges, suggesting there could be correlated suites of behaviors that should be considered when breeding for less aggressive pigs. Another important aspect to consider when addressing issues of aggression in group-housed pigs is their sociality. Social animals display a wide number of behaviors to maintain social bonds. Affiliative and agonistic behaviors were compared at 4 time points and revealed that certain affiliative behaviors are related to less aggression, suggesting potential for selection on positive social behaviors. Overall, the results of this research suggest that the role of individual behavior types in the social cohesion of group-housed pigs is important to consider. Future directions of this research will explore this idea in more depth and aim to guide pig producers on how to manage group-housed pigs in a way that not only reduces aggression but promotes positive social behaviors and good welfare."--Pages ii-iii.
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Title: Motherhood, stress, and serotonin receptors : influence on postpartum social and affective behaviors in female laboratory rats
Creator: Vitale, Erika
Date: 2020
Collection: Electronic Theses & Dissertations
Description: Mammalian mothers show a unique suite of behavioral responses beginning around the time of parturition that are necessary for successful rearing of young. These include caring for offspring, high levels of aggression, and low anxiety. These behaviors emerge in response to the unique neurochemical milieu resulting from pregnancy and parturition. Studies in this dissertation test the hypothesis that changes in receptors for the neurotransmitter serotonin (5-HT) are part of this neurochemistry...
Show moreMammalian mothers show a unique suite of behavioral responses beginning around the time of parturition that are necessary for successful rearing of young. These include caring for offspring, high levels of aggression, and low anxiety. These behaviors emerge in response to the unique neurochemical milieu resulting from pregnancy and parturition. Studies in this dissertation test the hypothesis that changes in receptors for the neurotransmitter serotonin (5-HT) are part of this neurochemistry in female laboratory rats. Experiments in chapter one found that there are reproductive state-dependent changes in expression of central 5-HT receptors that may be responsible for peripartum behavioral responses. Specifically, females examined at parturition and early lactation showed less serotonin 2C receptor (5-HT2C) mRNA expression in the midbrain dorsal raphe (DR), more serotonin 2A receptor (5-HT2A) mRNA in the medial preoptic area (mPOA), and more serotonin 1A (5-HT1A) mRNA in the shell subregion of the nucleus accumbens (NAcSh) compared to nulliparous females. Receptor autoradiography confirmed that binding density of 5-HT2A was higher in the mPOA of recently parturient females and that binding density of 5-HT1A in the NAcSh was higher in lactating females at particular rostrocaudal levels. Such differences in 5-HT receptor expression were not found in maternally acting virgin females, suggesting that pregnancy and parturition are necessary for these changes in central 5-HT receptors to occur. Because pregnancy stress derails most behavioral adaptations of motherhood, follow up experiments then explored whether the normative changes in 5-HT receptor expression across reproduction were prevented by daily application of mild-to-moderate stress beginning one week after mating. Stressed females showed lower maternal care and higher depression-like behaviors, which were correlated with 5-HT receptor mRNA in the mPOA, NAcSh and DR. Autoradiographic binding density of mPOA 5-HT2A receptors was not affected by pregnancy stress, although the stress reduced 5-HT1A binding in the NAcSh. Because the NAcSh is involved in motivation and reward processing, the last experiment directly tested whether 5-HT1A receptors in the NAcSh contribute to maternal caregiving and emotional behaviors. Long-term knock down of 5-HT1A in the NAcSh was established using an adeno-associated virus promoting shRNA against 5-HT1A mRNA. The 5-HT1A shRNA vector or a scrambled control vector was infused into the NAcSh during early pregnancy and mothers' later postpartum social and affective behaviors (i.e. caregiving, maternal motivation, aggression, anxiety- and depression-like behaviors) were observed. 5-HT1A knock down resulted in higher frequencies of self-grooming and sleeping away from the nest, delayed retrieval of displaced pups back to the nest, and increased anxiety-like behavior. Overall, I found that female reproduction is associated with changes in serotonin receptor expression in numerous brain sites involved in postpartum behavior. Of particular interest, the normative change in 5-HT1A expression in the nucleus accumbens shell is altered in response to stress during pregnancy, and disrupting its expression reduces maternal motivation and increases postpartum anxiety-like behavior. Together, the results from this dissertation provide new insights into how the serotonergic system contributes to postpartum social and affective behaviors and offer a potential mechanism via the brain's reward system through which pharmacological treatments that affect the serotonin system (e.g., SSRIs) may work to alleviate postpartum affective disorders in women.
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