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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
221

O lúdico e o agressivo na psicose infantil: contribuições da etologia a psicopatologia / The play and the aggressive behavior in psychotical children: contributions from ethology to psychopathology

Christian Ingo Lenz Dunker 22 August 1991 (has links)
Estudo observacional que descreve e analisa a ocorrencia dos comportamentos de agressao e brincadeira turbulenta em criancas psicoticas. Os ss sao 11 criancas, com idade entre 7 e 11 anos, de ambos os sexos, com diagnostico de psicose, frequentando instituicoes especializadas. Realiza 5 sessoes de observacao com cada crianca em situacao ludica, com duracao de 10 minutos cada, no local em que normalmente desenvolvem atividades recreativas. Utiliza contribuicoes da antropologia e da psicanalise na articulacao dos resultados. Verifica que os meninos interagem mais que as meninas; que entre as meninas e mais frequente a brincadeira turbulenta do que a agressao, ocorrendo o inverso com os meninos; ha modos preferenciais para a agressao (fisica) e para a brincadeira turbulenta. Constata oposicoes entre os dois comportamentos, tanto para padroes quanto para frequencia, cuja analise demonstra existir uma estrutura interna aos dois comportamentos, sugerindo uma relacao dialetica entre o simbolo e a imagem. Demonstra, parcialmente, a hipotese de que ha um predominio de linguagem iconica na psicose e que no interior dessa o comportamento se estrutura tal como essa linguagem, numa dialetica de ausencia e presenca e numa oposicao entre seus significantes comportamentais / Eleven children between de ages of seven and eleven diagnosed as psycotic were the subjects of na observational study. The research was looking for descriptions and ocurrences of the aggressive behavior and rough-and-tumble play. They were observed at two specialized institution. To the criteria of Blurton-Jones (1967) for rough -and-tumble new ones were added and also context variables were taken into account. Methodological problems linked to the question of the description in ethology and psychiatry were discussed as also the nosology tradition involved. Anthropological and psychoanalytical contributions were used on the articulation of results. It was verified that in general boys interact more than girls. Girls rough-and-tumble was more frequent than aggression. In the case of boys this differences did not appear. Boys are more aggressive than girls. Individual differences were great. There were preferential forms of aggression (physical) and of rough-and-tumble different for each sex. Oppositions shown between one and another behavior were found which refer to motor patterns and occurrences. This opposition was analysed to demonstrate an internal structure to both behavior which leads us to believe that a dialectical relationship exists between the symbol and the image. From this it suggested that behavior has the same structure as a language.
222

Maternal Effects in Transmission of Self-Medicative Behavior from Mother to Offspring in Sheep

Sanga, Udita 01 May 2010 (has links)
Mammals begin learning food preferences in utero and maternally mediated influences early in life help offspring develop their feeding habits. Mammals also learn by individual experience to ingest medicinal compounds such as polyethylene glycol (PEG), which attenuates the negative post-ingestive effects of tannins, a group of potentially toxic plant secondary compounds. The objective of this study was to investigate the transmission of acquired self-medicative behavior from mother to offspring using polyethylene glycol (PEG) as a medicine to relieve malaise caused by tannins. I hypothesized that: 1) mothers trained to associate the beneficial effects of PEG while consuming tannins will pass this information to their offspring, and 2) lambs will be more efficient at utilizing PEG as a medicine against tannins in the presence of mother than lambs which learn without the influence of the mother. This hypothesis was evaluated in four phases: in the first phase, a group of ewes (Experienced) was conditioned to associate the beneficial effects of PEG after consuming a tannin-containing diet. Ewes were offered a meal of high-tannin food and PEG and subsequently, the high-tannin food and grape pomace (GP) with little nutritional and no "medicinal" effects. In the second phase, the experienced and a naïve group of ewes (Inexperienced) were given a choice between the high-tannin food, PEG, and GP. In the third phase, experienced and inexperienced ewes with their naïve lambs, and the group of naïve lambs without their mothers, were exposed to the tannin-containing diet, PEG, and GP. Finally, in the fourth phase, lambs were separated from their mothers, and lambs from all groups were offered a choice between the tannin-containing diet, PEG, and GP. Lambs from experienced and inexperienced mothers showed a higher preference for PEG than lambs exposed without their mothers who tended to show a higher preference for GP. Thus, the presence of mother (experienced/inexperienced) was important for naïve lambs to learn about the medicinal benefits of PEG. This source of trans-generational knowledge could aid in maintaining the information in the herd, increasing the efficiency and reducing the risk of learning about foods and environments exclusively by individual experience.
223

What Makes Our Minds Human? Comparative Phylogenetic Perspectives on the Evolution of Cognition

MacLean, Evan January 2012 (has links)
<p>What makes our minds human? How did they evolve to be this way? This dissertation presents data from two complementary lines of research driven by these orienting questions. The first of these explores the `what' of human cognitive evolution through comparative studies with chimpanzees and bonobos. The general aim of these studies is to understand which aspects of cognition are unique to humans, and which are shared with our closest living relatives. Chapters 2-3 test the hypothesis that humans have unique cognitive skills for reasoning about the attention of other individuals (theory of mind), and unique motivation to use these skills in cooperative contexts with conspecifics. In Chapter 2 I show that understanding others' attention is unlikely to be the `small difference that makes the big difference', as some researchers have proposed. However, my data support the possibility that species differences in the ontogeny of these skills may have robust consequences for the adult cognitive phenotype. In Chapter 3 I show that (contrary to previous reports) nonhuman apes are also motivated to engage in some simple triadic social activities, which resemble those characteristic of human children. Again however, I identify important differences between humans and other apes in their spontaneous preferences for these types of activities, and their attitudes toward a partner when cooperative behaviors are interrupted. The second half of this dissertation (Chapters 4-5) explores the `why' and `how' of cognitive evolution. Chapter 4 outlines the kind of research questions and methods that comparative psychologists will need to embrace in order to use the comparative method to its full potential in the study of cognitive evolution. Chapter 5 provides a proof of principle for this approach using a dataset including 33 species tested on two cognitive tasks measuring inhibitory control. Here I show that cognitive skills for inhibitory control are closely related to phylogeny across species, and strongly predicted by absolute (but not relative) brain size. Further, I show that two of the other leading hypotheses put forth to explain primate intelligence, namely sociality and diet, do not predict cognitive skills on these tasks. These data illustrate the power of the comparative method for understanding cognitive evolution, and provide a starting point for future studies embracing this approach. Collectively, this research refines our understanding of how human cognition differs from that of other primates, and illustrates the utility of studying cognitive evolution from an explicitly phylogenetic comparative framework.</p> / Dissertation
224

A Computational Synthesis of Genes, Behavior, and Evolution Provides Insights into the Molecular Basis of Vocal Learning

Pfenning, Andreas R. January 2012 (has links)
<p>Vocal learning is the ability modify vocal output based on auditory input and is the basis of human speech acquisition. It is shared by few distantly related bird and mammal orders, and is thus very likely to be an example of convergent evolution, having evolved independently in multiple lineages. This complex behavior is presumed to require networks of regulated genes to develop the necessary neural circuits for learning and maintaining vocalizations. Deciphering these networks has been limited by the lack of high throughput genomic tools in vocal learning avian species and the lack of a solid computational framework to understand the relationship between gene expression and behavior. This dissertation provides new insights into the evolution and mechanisms of vocal learning by taking a top-down, systems biology approach to understanding gene expression regulation across avian and mammalian species. First, I worked with colleagues to develop a zebra finch Agilent oligonucleotide microarray, including developing programs for more accurate annotation of oligonucleotides and genes. I then used these arrays and tools in multiple collaborative, but related projects, to measure transcriptome expression data in vocal learning and non-learning avian species, under a number of behavioral paradigms, with a focus on song production. To make sense of the avian microarray data, I compiled microarray data from other sources, including expression analyses across over 900 human brain regions generated by Allen Brain Institute. To compare these data sets, I developed and performed a variety of computational analyses including clustering, linear models, gene set enrichment analysis, motif discovery, and phylogenetic inference, providing a novel framework to study the gene regulatory networks associated with a complex behavior. Using the developed framework, we are able to better understand vocal learning at different levels: how the brain regions for vocal learning evolved and how those brain regions function during the production of learned vocalizations. At the evolutionary level, we identified genes with unique expression patterns in the brains of vocal learning birds and humans. Interesting candidates include genes related to formation of neural connections, in particular the SLIT/ROBO axon guidance pathway. This algorithm also allowed us to identify the analogous regions that are a part of vocal learning circuit across species, providing the first quantitative evidence relating the human vocal learning circuit to the avian vocal learning circuit. With the avian song system verified as a model for human speech at the molecular level, we conducted an experiment to better understand what is happening in those brain regions during singing by profiling gene expression in a time course as birds are producing song. Surprisingly, an overwhelming majority of the gene expression identified was strongly enriched in a particular region. We also found a tight coupling between the behavioral function of a particular region and the gene expression pattern. To gain insight into the mechanisms of this gene regulation, we conducted a genomic scan of transcription factor binding sites in zebra finch. Many transcription factor binding sites were enriched in the promoters of genes with a particular temporal patterns, several of which had already been hypothesized to play a role in the neural system. Using this data set of gene expression profiles and transcription factor binding sites along with separate experiments conducted in mouse, we were able uncover evidence that the transcription factor CARF plays a role in neuron homeostasis. These results have broadened our understanding of the molecular basis of vocal learning at multiple levels. Overall, this dissertation outlines a novel way of approaching the study of the relationship between genes and behavior.</p> / Dissertation
225

Patterns of affiliation and agonism in a ringtailed lemur, Lemur catta, society tests of the socioecological model and other hypotheses /

Sbeglia, Gena. January 1900 (has links)
Title from title page of PDF (University of Missouri--St. Louis, viewed March 8, 2010). Includes bibliographical references.
226

Energetic Costs of Reproductive Effort in Male Chimpanzees

Georgiev, Alexander 14 September 2012 (has links)
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
227

Causes and Consequences of Cooperative Construction in the Mice Mus spicilegus and Peromyscus polionotus

Tong, Wenfei 14 March 2013 (has links)
The cooperative construction of shared dwellings is a phylogenetically-widespread evolutionary puzzle. Shared shelters are common goods – all individuals in the shelter benefit, at the expense of those individuals that contribute to the construction. The evolution of cooperation requires existing variation for selection to act upon and genetic benefits to cooperators, through inclusive fitness or direct rewards. This study focuses on two genera of mice, Mus and Peromyscus, to examine shared construction and social monogamy as potential transitions to more sophisticated forms of sociality, such as cooperative breeding. The mound-building mouse (Mus spicilegus) is named for the large mounds that groups of mice build and beneath which they overwinter. Variation in mtDNA and 14 microsatellites show limited genetic structure across the geographic range of M. spicilegus. Mice from the same mound are more genetically related than mice from different mounds, and males and females associated with a mound are equally likely to be relatives. However in spring, when breeding begins, male kin are more likely to share a territory than are female kin. One possible interpretation is that males associate with kin to minimize the costs of being cuckolded, as this study finds evidence of multiple paternity in every litter genotyped. By increasing the chances of the cuckold being a brother, a male still gains inclusive fitness benefits from paternal care to extra-pair offspring in this socially monogamous species. Behavioral experiments show that another socially monogamous mouse species, the oldfield mouse (Peromyscus polionotus), can coordinate construction with unfamiliar, unrelated conspecifics. In contrast, two other closely related Peromyscus species do not dig longer burrows in pairs than they would have as individuals. Male-female P. polionotus pairs tend to dig longer burrows than pairs of the same sex, but males within opposite sex pairs do most of the digging, particularly when paired with an unfamiliar female. Male burrowing could be the product of female choice in this monogamous species. In M. spicilegus and P. polionotus, shared parental care and construction shed light on the evolution of cooperation and conflict.
228

The Evolution and Development of Inequity Aversion

McAuliffe, Katherine Jane 08 June 2015 (has links)
Humans show such strong sensitivity to whether resources are distributed fairly that they sacrifice personal gain to avoid distributional inequity. This inequity aversion plays an important role in guiding human social decision-making and appears to be ubiquitous across human populations. However, we currently do not understand whether or how inequity aversion evolved over the course of human evolution or how it develops in children. / Human Evolutionary Biology
229

A multidimensional perspective on the role of behavior in evolution

Munoz, Martha Monica 23 October 2014 (has links)
Behavior determines how organisms interact with their environment, and has long been posited as a pacemaker for evolution. The classical view is that novel behaviors expose organisms to new selective pressures, in turn "driving" evolution. Behavior can also restrain evolutionary change. Some behaviors, such as thermoregulation, help organisms maintain a constant selective environment, thus "inhibiting" evolution. This thesis seeks to understand the role of behavior in influencing the evolutionary process. In the first part, I test the hypothesis that the same behavior can simultaneously impede and impel evolution in different traits. I focus on the lizard, Anolis cybotes, from the Caribbean island of Hispaniola. Through a replicated field experiment I show that behavioral flexibility allows these lizards to maintain a constant body temperature in markedly different thermal habitats. I determine that this similarity in body temperatures is associated with physiological stasis, as the preferred temperature and heat tolerance are nearly identical among populations. I demonstrate that the behavioral change allowing lizards to maintain a constant body temperature involves a perch switch. Finally, I demonstrate that this shift in structural habitat use from trees at low elevation to rocks at high elevation in turn impels morphological evolution in traits associated with rock use, and that these traits are likely genetically based. Thus, a perch switch to rocks at high elevation is simultaneously impeding physiological evolution, whilst impelling morphological evolution. In the second part of my study, I asked whether rates of evolution differ among physiological traits, and how thermoregulation influences these rates. I found that cold tolerance evolves significantly faster than heat tolerance in the cybotoid anoles, a clade of anoles that contains A. cybotes and its relatives. I demonstrate that thermal variation is considerably greater during the day than at night and, at high elevation, nighttime temperatures are so cold that they would incapacitate most lizards. In the absence of thermal refuges and behavioral buffering, lizards at high elevation have no choice but to adapt their physiology. Thus, the ability to thermoregulate during, but not at night, likely influences differences in rates of evolution between heat and cold tolerance.
230

Nesting behavior in a reintroduced population of California condors

Sandhaus, Estelle A. 14 January 2013 (has links)
Studies in numerous animal taxa demonstrate that early rearing experience has a profound influence on the development of later adaptive behavior. This has implications for endangered species management, particularly when animals are reared in captivity for reintroduction or in cases in which species managers play an active role in managing animals at the individual or population levels. The California condor (Gymnogyps californianus) is a critically endangered New World vulture that was subject to a period of extinction in the wild followed by ongoing reintroduction in portions of its native range. Though the reintroduced population in southern California is largely adapting well, several obstacles to viability remain that are primarily anthropogenic in nature. The purpose of this study was to quantitatively assess nesting behavior of free-flying California condors in the southern California population to determine whether differences in parental care and nestling behavior are attributable to parental rearing conditions and experience. Hierarchical generalized linear modeling was used to analyze parent and chick activity budget data. Differences among condors were not detected in attendance patterns across either the egg or chick phases of nesting. Variation was not detected among chicks in proportion of time spent active and inactive during the early nestling phase. Variations among older nestlings in the proportion of time spent inactive were observed, with associations detected between inactivity, pair, visibility and season. The proportion of time that parents interacted with nestlings varied from nest to nest, with associations detected between interaction, visibility and season. Finally, potential pair-level variation in the propensity to bring microtrash to the nest was observed. It is concluded that while visibility is often overlooked in behavioral analyses, it is methodologically important to account for this variable in analyses of condor nestling behavior. Further, while some pair-level variation in allocation of care to nestlings is apparent, this appears to be a function of factors not related to individual developmental differences.

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