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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.
51

THE CAUSES AND CONSEQUENCES OF INDIVIDUAL VARIATION IN PARENTAL CARE BEHAVIOR

Wetzel, Daniel P. 01 January 2013 (has links)
Behavioral traits can be remarkably flexible depending on the conditions in which they are expressed, yet, in spite of this flexibility, persistent differences between individuals appear to limit the potential expression of behaviors. For example, despite evidence that parents provide variable amounts of parental care in response to changing environmental conditions, they also differ in the overall level of care they provide. I used a behavioral reaction norm approach to study individual variation in parental care behavior in free-living house sparrows (Passer domesticus). I investigated the nature of this variation by studying the relationship between different forms of parental care, the biological basis of individual variation in care, and the effect of this variation in care on offspring. First, I found a positive covariance between nestling provisioning and nest defense. Parents that provided high levels of care in one context provided high levels of care in the other context, even after accounting for measures of offspring value. Second, I sought to identify the biological sources that create and maintain consistent individual differences in the level of care a parent provides. I found that the likelihood of feeding nestlings large food items was positively associated with genetic heterozygosity, but did not find evidence that nestling provisioning was influenced by additive genetic variation in this population. Parents hatched from larger eggs provisioned offspring at a higher rate than parents hatched from smaller eggs, but there was no effect of other conditions experienced in the nest on the level of care expressed as an adult. I also tested if differences in problem-solving ability were related to differences in parental care behavior. Although I found that problem-solving parents fledged more offspring than parents that could not solve the problem, parental care was not associated with any measure of problem-solving ability. Finally, I found that individual variation in parental care reaction norms predicted the growth rate, size, and immune response of nestlings, which in turn positively affected offspring survival and recruitment. My findings reveal factors maintaining individual differences in parental care behavior and offer new insights into the causes and consequences of individual variation.
52

Selective Utilization of Microhabitats by Web-building Spiders

Welch, Kelton D. 01 January 2013 (has links)
Natural enemies are members of complex ecological communities, and their ability to contribute to the biological control of pest organisms is strongly influenced by a convoluted network of ecological interactions with many other organisms within these communities. Researchers must develop an understanding of the mechanisms that shape trophic webs to predict and promote top-down effects of predators. The behavior of predators can have a strong influence on their potential as biological control agents. Web-building spiders are a useful example organism for the study of natural enemy behavior because of the experimentally tractable nature of their foraging behavior. Specifically, patterns in microhabitat utilization and web construction by spiders provide insights into foraging behavior and pest-suppression potential. In field collections, spiders were found to utilize microhabitats in a species-specific manner. Molecular gut-content analysis and a mathematical model showed that two spiders belonging to different web-building guilds differed in their dependence on microhabitat-specific prey activity-densities. In particular, the sheet-weaving guild constructed webs in microhabitats with the highest densities of springtails (Collembola). High dependence on this non-pest prey also correlated with evidence of increased intraspecific competition, and implies a potential negative effect of springtails on the consumption of pest insects, such as aphids. In laboratory two-choice assays, sheet-weaving spiders selected microhabitats and constructed webs in a flexible, stepwise manner, which allowed spiders to regulate their investment of silk resources to match the profitability of the microhabitat. Spiders also exhibited prey-specific shifts in foraging behavior, constructing webs in the presence of mobile, non-pest springtails, but utilizing active foraging tactics in the presence of sedentary, pest aphids. However, in factorial no-choice assays, pest-consumption rates were not significantly affected by the presence of non-pest springtails, indicating that prey-specific foraging-mode shifts are compatible with biological control. From these results, it is clear that the flexible foraging behavior of web-building spiders has a strong influence on their roles in ecological communities and their position within food webs. This dissertation highlights the importance of understanding the nuances of natural-enemy behavior for properly assessing and promoting biological control services.
53

Behavioral Responses of Male Parasitic Wasps to Plant Cues: A Comparison of Two Host-Plant Complex Sources of Cotesia congregata (Say)

Ayers, Megan 01 January 2015 (has links)
Prior exposure to plants cues can enhance assortative mating in insects. We hypothesized that, as previously reported for females, males of Cotesia congregata would display inherent responses to plant cues that could be modified by postemergence experience and further, that males originating from two different host-plant complexes (HPCs) would display different behavioral responses to these HPCs. In no-choice contact assays with a non-host plant, searching responses of males and females increased sharply at Day 2 and remained stable through Day 4. In no-choice assays with potential host plants, males searched longer on catalpa than tobacco; responses were not modified by postemergence experience. In choice assays with both HPCs, naïve males did not display orientation preferences; however, males experienced with their natal plant preferred their natal HPC. Results indicate that postemergence experience on the natal host plant induces an orientation preference for the natal HPC and thus, can facilitate assortative mating.
54

RESPONSES OF THE CATALPA SPHINX, CERATOMIA CATALPAE, AND ITS PRIMARY PARASITOID, COTESIA CONGREGATA, TO VARYING LEVELS OF IRIDOID GLYCOSIDES IN CATALPA

Bray, Jessica L 01 January 2015 (has links)
The catalpa sphinx, Ceratomia catalpae, is a specialist on Catalpa trees, which produce iridoid glycosides (IGs). Whereas some trees are defoliated every year, others escape herbivory. Caterpillar populations are either heavily parasitized by the braconid wasp, Cotesia congregata, or remain unparasitized. We hypothesized that these patterns could be explained by variable IG concentrations among trees and insect responses to these chemicals. IG concentrations varied among trees. Percent defoliation was positively related to IG concentration. In comparisons of insect responses to relatively high or low IG concentrations, moths preferred to oviposit on trees with high IG concentrations. Caterpillars did not display a feeding preference nor did wasps differ in searching responses to leaf discs with high or low IG concentrations. Results indicate that observed patterns of herbivory can be explained by moth oviposition preferences for trees with high IG concentrations.
55

Etogramy obratlovců ve výuce biologie / Vertebrate ethograms for secondary schools

Peřka, Jaroslav January 2015 (has links)
The aim of this thesis is to create an educational programme for teaching ethology at grammar schools, in which theoretical knowledge will be directly linked with practical activities. To fulfil the goals of this ethological educational programme there is used the creation of ethograms.The whole educational programme is divided into three parts. In the first part pupils are acquainted with the theory of ethology and individual types of animal behaviour and also with the principles of direct observation of animals, the creation of ethological records and their evaluation. In the second part pupils observe directly a chosen animal in zoological gardens or similar institutions and on the basis of their obtained theoretical knowledge they describe its behaviour to previously prepared forms. In the third part pupils create ethograms of vertebrates based on the gained data, which are part of an expert seminar paper in a form of an expert text, a power-point presentation or a poster. In these papers pupils keep the basic format and content rules for ethogram creation.To determine the suitability, adequacy and benefits of this educational programme there is used the evaluation of the output papers created by pupils, a questionnaire and the findings acquired from the realization of the whole programme. The...
56

Occurrence and genetic diversity of lemon sharks (Negaprion brevirostris) at a nursery ground at the Chandeleur Islands, Louisiana.

McKenzie, Jonathan F 17 May 2013 (has links)
Anecdotal evidence suggested that immature lemon sharks (Negaprion brevirostris) occur at the Chandeleur Islands in southeastern Louisiana. From May 2009 to August 2011, the Nekton Research Laboratory at the University of New Orleans regularly sampled habitats at the Chandeleur Islands to confirm the presence of immature individuals of this species. During these efforts, 147 immature lemon sharks (neonates, young-of-the-year, and juveniles) were collected. Each shark was PIT tagged and a tissue sample was taken for genetic analyses. Sizes ranged from 56 – 177 cm total length. Sharks showed a preference for sandy substrate and smaller individuals showed significant preference for shallow waters. Collection data for N. brevirostris were obtained from various locations around the Gulf of Mexico for comparison. Based on a review of current literature, collection data, and microsatellite analysis it was possible to classify the Chandeleur Islands as an elasmobranch nursery ground under the definition presented by Huepel et al. (2007). Current literature and high densities of N. brevirostris suggests that the Chandeleur Islands are the only area in the northern Gulf of Mexico where neonatal and YOY lemon sharks have been recorded. Results from a combination of SPOT 5 satellite tags, PIT tags, and FLOY tags show that immature N. brevirostris at the Chandeleur Islands remain in the vicinity of the islands for several months. The abundance of juvenile sharks across years provides evidence of continuous use of these islands as a pupping area. Genetic analysis supports this information with 7 of 15 mothers returning across years. The combination of this information indicates that the Chandeleur Islands are the northern- and western-most documented nursery ground for this species. Special care should be given to this habitat as CPUE for N. brevirostris decreased significantly during this research following the 2010 Deepwater Horizon disaster and subsequent oil prevention measures. Genetic research indicates a high level of inbreeding and genetic separation between the Chandeleur Islands population and other known populations in Florida, Belize, and the Bahamas.
57

Chasin’ Tail in Southern Alabama: Delineating Programmed and Stimulus-driven Grooming in Odocoileus virginianus

Heine, Kyle 11 August 2015 (has links)
This study examined variation in ectoparasite density and grooming behavior of naturally occurring white-tailed deer (Odocoileus virginianus) in southwest Alabama. Stimulus-driven grooming as well as the intraspecific body size and vigilance principles of programmed grooming were tested. During the rut, males had a higher average tick (Ixodidae) density than females and exhibited complete separation of tick parasitism between non-rutting and rutting periods, supporting the vigilance principle. Stimulus-driven grooming was supported, as both fawns and yearlings had significantly higher fly (Hippoboscidae) and combined fly/tick densities than adults, and fawns oral groomed at a significantly higher rate than adults, even in the absence of allogrooming. Programmed and stimulus-driven grooming of deer examined in this study were not mutually exclusive but ectoparasite dependent.
58

Sledování sociálního chování u morčat v modelové situaci

ELIÁŠ, Zdeněk January 2019 (has links)
The aim of this work was to find out the social behaviour and interactions among the established group of guinea pigs (Cavia aperea var. porcellus) and the newly assembled groups, with each group being monitored three times, always for 24 hours. A total of 12 short-haired guinea pigs of smooth coat breed with balanced age distribution, divided into three groups, were monitored. The behaviour and activities of guinea pigs were recorded on a camcorder followed with subsequent evaluation of video recordings by means of ethograms and verbal description. Among monitored and evaluated activities were rest and sleep, feed and water intake, comfort behaviour, movement and conflict. In guinea pigs, there were proven differences in behaviour for all of the activities monitored. The individuality of individuals and their different behaviours manifested themselves, with each of them behaving a little bit differently from the others. By comparing the groups, significant differences in behaviour were found. Each individual behaved a little bit differently, but the same pattern of behaviour was not repeated among the groups. Also, it was found that the number of conflicts among guinea pigs decrease overtime for which the guinea pigs are together.
59

Preferência e desuso de objetos de enriquecimento ambiental em suínos confinados / Preference and disuse of environmental enrichment objects in confined pigs

Santos, Jonathan Vinícius dos 15 August 2018 (has links)
A manutenção do bem-estar animal no setor da suinocultura é um dos maiores desafios para os modernos sistemas de produção devido principalmente à intensificação, que acarreta aumento do estresse dos animais confinados. O objetivo do presente estudo foi avaliar a preferência de suínos por objetos suspensos como enriquecimento ambiental, desuso, comportamento social e parâmetros fisiológicos, submetidos a diferentes ambientes enriquecidos em Câmara de Preferência Ambiental (CPA). Foram utilizados 60 leitões com idade média de setenta dias (dez semanas), divididos em dois grupos contemporâneos. Na fase 1 foi realizada uma classificação hierárquica de 30 leitões, mantidos na baia da granja, de acordo com os comportamentos de bater, sem o revide da ação inicial, por três dias consecutivos, totalizando dezoito horas de observação, das 07h00 às 10h00 e das 15h00 às 18h00. Em seguida, após determinada a hierarquia, os leitões foram para a CPA, onde foram alojados 2 leitões (subordinados) em cada baia \"companhia\" e nas baias \"teste\" foram alojados 5 leitões (2 dominantes e 3 intermediários), por cinco dias (D-1, D0, D1, D2 e D3), e a cada semana um novo grupo de leitões \"teste\" foi introduzido na CPA. Esta metodologia foi repetida por quatro semanas com o primeiro grupo (fase 1). A fase 2 repetiu as observações de hierarquia e preferência com um novo grupo de 30 leitões. O delineamento experimental foi inteiramente casualizado. Os tratamentos foram os diferentes objetos suspensos para enriquecer o ambiente, inseridos a partir do dia 1 e retirados ao final da tarde: garrafa pet (politereftalado de etila) (objeto 1), corda de sisal (objeto 2), corrente (objeto 3) e ambiente controle (sem enriquecimento), cada qual em um dos compartimentos da CPA aleatoriamente. Durante todo o período experimental foram anotados a cada dez minutos os comportamentos individuais dos leitões, totalizando seis horas de observação comportamental diária, das 08h00 às 11h00 e das 13h00 às 16h00. Para avaliação destes comportamentos foi utilizado um etograma de trabalho com os parâmetros: agonístico, ócio, comendo, bebendo, vocalizando, estereotipia, positivos (lúdico, explorar, brincando com o enriquecimento) e outros. Foi caracterizado o ambiente térmico dentro de cada compartimento da CPA durante todo o período experimental por data logger (modelo U12-012) a cada quinze minutos e realizadas avaliações fisiológicas como: frequência respiratória, temperatura superficial da nuca por meio de câmera termográfica Termovisor (Alemanha) e colheita do fluído oral em dias alternados, no D0 e D2 de apenas um suíno companhia aleatório por compartimento e um suíno teste, duas vezes ao dia, às 07h00 e 13h00. Para a análise estatística dos dados comportamentais foi utilizado o procedimento GLIMMIX do SAS utilizando animal como medida repetida. Os tratamentos foram comparados pelo teste-t a 5%. O objeto que mais foi procurado e interagido pelos suínos foi a corda de sisal, com um total de 70,8 minutos e 36,5 eventos durante os três dias de exposição ao enriquecimento, seguido da garrafa pet e da corrente. Nas categorias dominante e intermediária o comportamento que apresentou maior frequência em relação aos outros comportamentos foi o ócio (P<0,05). Para os suínos subordinados, o comportamento mais frequente foi o ócio, seguido por comer e positivos (P<0,05). A temperatura ambiente dentro da CPA não diferiu (P>0,05) entre os compartimentos. A temperatura superficial da nuca foi maior (P<0,05) no período das 13h00 em relação ao das 7h00, porém, sem diferença para a concentração de cortisol (P>0,05). Com isso, conclui-se a preferência dos suínos foi pela corda de sisal, com desuso gradual de três dias, alterando a frequência comportamental, porém, a mesma não interferiu nos parâmetros fisiológicos estudados, demonstrando que não houve estresse nos animais. / The welfare maintenance in swine production is one of the main challenges in modern systems mainly due to intensification of animal production, which leads to increase in stress of confined animals. The aim of the present trial was to evaluate preference of piglets for suspended objects such as environmental enrichment, disuse, social behavior and physiological parameters, submitted to different environments enriched in Environmental Preference Chamber (EPC). Sixty piglets with 70 days of average age (10 weeks) were used; they were divided into two contemporary groups. On phase 1, a hierarchical classification of 30 piglets was realized, kept at farm\'s barn, according to the agonistic standards of fighting, beating and mounting other piglets in the same pen, when did not have retaliate from the initial action, for three consecutive days, totaling 18 hours of observation, from 7 to 10 am and from 3 to 6 pm. Then, after reaching the hierarchy organization, piglets were placed in the EPC, where two piglets (subordinates) were housed in each \"company\" pen and in the \"test\" pens five piglets (2 dominants and 3 intermediates) were housed for 5 days (D-1, D0, D1, D2 and D3), and each following week a new group of piglets \"test\" was introduced in the EPC. This methodology was repeated for 4 weeks with the first group (phase 1). Phase 2 repeated the hierarchy and preference observations with a new group of 30 piglets. The experimental design was a completely randomized. The treatments were the different objects suspended to enrich the environment, inserted on day 1 and removed in the afternoon: sisal rope; chain; PET bottle (polyethylene terephthalate) and control environment (without enrichment), each one placed at a EPC compartment, randomly. Throughout the experimental period, individual behaviors of the piglets were registered every 10 minutes, totaling 6 hours of daily behavioral observation, from 8 to 11 am and from 1 to 4 pm. In order to evaluate these behaviors, we used a ethogram with the parameters: agonistic, playful, idleness, eating, drinking, exploring, vocalizing, stereotyping, playing with the object and others. The thermal environment was characterized within each EPC compartment throughout the experimental period by HOBO (model U12-012) data logger every 15 minutes and physiological evaluations were performed, such as: respiratory rate, neck surface temperature by thermographic camera Thermovisor Testo® (Germany) and oral fluid harvest on alternate days, at D0 and D2 from only one random company pig per compartment and one swine test, twice daily, at 7 am and 1 pm. For the statistical analysis of the behavioral data GLIMMIX SAS procedure, using animal as a repeated measurement was used. Treatments were compared through PDIFF and t test at 5%. The sisal rope was the most used object, with a total interaction of 70.8 minutes and 36.475 events during the three days of enrichment exposure, followed by the pet bottle and the chain. The behavior that presented the highest frequency was idleness (P<0.05) for dominant and intermediate pigs. For subordinate pigs, the most frequent behavior was idleness, followed by eating, exploring and playing with the object (P<0.05). The ambient temperature within the EPC did not differ (P>0.05) between the compartments. The superficial temperature of the neck differed (P<0.05) in the period of 1 pm compared to 7 am, however, cortisol concentration did not differ (P>0.05). Therefore, we concluded that the most sought and interacted object was the sisal rope, with a gradual disuse of three days, altering the behavioral frequency, however, it did not interfere in the studied physiological parameters, showing no signs of animal stress.
60

Evolução do cleptoparasitismo em Argyrodes elevatus (theridiidae, aranae)

Silveira, Marco Cesar 01 June 2009 (has links)
O cleptoparasitismo é uma interação entre animais que consiste no furto ou roubo de itens alimentares já coletados ou processados. Este tipo de interação ocorre em diversos táxons animais. Entre aranhas, a subfamília Argyrodinae (Theridiidae) é um dos grupos com mais espécies cleptoparasitas. Neste estudo, apresentamos um apanhado de ações que o cleptoparasita Argyrodes elevatus foi capaz de realizar nas teias de aranhas hospedeiras. As principais espécies de hospedeiras observadas foram Latrodectus curacaviensis, Latrodectus geometricus e Achaearanea tepidariorum (Theridiidae); destas, apenas A. tepidariorum é uma hospedeira natural de A. elevatus. A maioria das observações se deu em laboratório, mas também relatamos dados de campo. Registramos que A. elevatus pode, na teia de sua hospedeira, furtar presas sem ser percebido ou roubá-las coercivamente. Ele pode ainda furtar ootecas; capturar presas por si próprio e até mesmo predar a aranha hospedeira. Em seguida, apresentamos as sequências de categorias comportamentais que A. elevatus executa durante o furto de presas em teias da hospedeira L. curacaviensis. A partir destas sequencias, o programa EthoSeq nos mostra os conjuntos de categorias com mais probabilidade de conexão entre si (rotinas comportamentais) e nos permite a elaboração de um fluxograma do comportamento de furto de presas. Posteriormente, comparamos as categorias e as rotinas comportamentais que ocorrem no furto de presas com as categorias e rotinas que ocorrem no forrageamento de aranhas não cleptoparasitas. Com isto, demonstramos que A. elevatus tem maior plasticidade comportamental e capacidade cognitiva mais alta que espécies não cleptoparasitas da mesma família. Esta maior plasticidade comportamental está associada à execução, em contexto de aquisição de alimento, de comportamentos que são típicos de outros contextos, como agonismo ou exploração de novos ambientes. A. elevatus, portanto, é adaptado a lidar simultaneamente com diferentes contextos na teia de uma hospedeira. Pudemos, desta maneira, acrescentar elementos às propostas atuais que procuram explicar a evolução do cleptoparasitismo em Argyrodinae, em especial no que se refere à plasticidade comportamental. Por fim, propomos um modelo que mostra que a causa imediata do aumento da capacidade cognitiva de A. elevatus pode ser um aumento na interação entre diferentes módulos cognitivos nesta espécie. / Kleptoparasitism is an animal interaction consisting in stealth of collected or processed food items. It occurs on many animal taxa. Among spiders, the subfamily Argyrodinae (Araneae) is one of the groups with more kleptoparasite species. In this study, we present a set of different actions that the kleptoparasite Argyrodes elevatus can do in host spiders webs. Observed host species were mainly Latrodectus curacaviensis, Latrodectus geometricus and Achaearanea tepidariorum (Theridiidae), but only A. tepidariorum is a natural host of A. elevatus. Most observations were made in laboratory, but we also included field data. We registered that A. elevatus, in a host web, can steal a prey item without being perceived by the host spider, or rob it coercively. We also observed A. elevatus stealing eggsac, capturing preys by himself, and killing the host spider. We present sequences of behavioural units that A. elevatus performs during the stealth of preys in L. curacaviensis webs. From these sequences, the software EthoSeq shows the sets of behavioural units with higher probability of connection. These sets are called behavioural routines. After that, we could build an ethogram and compare the units and routines of A. elevatus prey stealth behaviour with the units and routines of non-kleptoparasite spiders prey capture behaviour. With this comparison we show that A. elevatus has a higher behavioural plasticity and cognitive ability than non-kleptoparasite theridiid spiders. The higher behavioural plasticity is related to the occurrence; during foraging bouts, of behaviours typical of other contexts, such as agonism or site selection. Therefore, A. elevatus is adapted to behave in many different contexts simultaneously in a host web. Our results improve the current hypothesis concerning evolution of kleptoparasitism in Argyrodinae through the discovery of further plasticity in the taxa. Furthermore, we propose a model for the increase in the cognitive ability of A elevatus. In this model, cognitive increase is obtained through the interaction between distinct cognitive modules in this species.

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