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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.
21

The Evolution and Ecology of Learning and Social Behaviour in Insects

Durisko, Zachary T. 10 1900 (has links)
<p>Animals utilize information about their environments in order to adaptively modify behaviour. Such information may come from individual experience or from social sources, both of which have costs and benefits to the animal. Here I first show benefits of individual learning with respect to foraging performance, a good proxy of fitness, in bumblebees in a naturalistic setting. Second, I show that despite fitness costs associated with learning, fruit flies do not modify their investment in learning ability due to environmental complexity of larval foraging environment. Third, I show that fruit fly larvae utilize social information in their foraging decisions, including social learning, despite increased competition costs. Fourth, I show that adult fruit flies also use the presence of larvae as a source of social information to find suitable food patches. Finally, I show that larvae spontaneously form small foraging aggregations, one benefit of which may be an improved ability to dig and burrow into the surface of the food. I discuss the costs and benefits of both individual and social learning, as well as the potential for insect model systems in future studies of sociality and learning.</p> / Doctor of Philosophy (PhD)
22

Social decision-making in a group living cichlid fish

Reddon, Adam R. 10 1900 (has links)
<p>For my doctoral research I examined social decision-making in a cooperatively breeding cichlid fish, <em>Neolamprologus pulcher</em> with a focus on affiliation and aggression. I investigated the role that the nonapeptide hormone, isotocin, plays in modulating social decisions in these contexts. I show that <em>N. pulcher</em> males prefer to join larger groups regardless of the rank at which they will join, whereas females prefer larger groups only when they can join a group in a high rank (Chapter 2). I examined decision-making during resource contests in<em> </em>(Chapter 3) and found that <em>N. pulcher</em> are sensitive to the size of their opponents, making fighting decisions depending on their opponents’ body size. I also found that smaller <em>N. pulcher</em> are more motivated to persist within contests, showing a shorter latency to resume fighting following interruption (Chapter 4). In Chapters 5 and 6, I explored the role of isotocin (the teleost fish homologue of oxytocin) in regulating social behaviour. I discovered that an increase in isotocin increased responsiveness to social information. Fish treated with isotocin were more sensitive to their opponent’s size in contests and were more submissive to dominant individuals within their social group (Chapter 5). Unexpectedly, I found that exogenous isotocin reduced sociality in <em>N. pulcher, </em>and that an isotocin receptor antagonist increased it (Chapter 6). These results suggest that the relationship between isotocin and social behaviour is both complex and context specific. In my final data chapter, I used social network analysis to explore the role of dominance interactions in determining the structure of <em>N. pulcher</em> social groups. I found that <em>N. pulcher</em> dominance hierarchies are highly linear, but that dominance interactions are not predicted by sex or body size asymmetry (Chapter 7). I found that conflict within <em>N. pulcher</em> social groups is greatest at the top of the dominance hierarchy. Taken together the results of my thesis helps to elucidate the behavioural and hormonal basis of social decision-making in a cooperatively breeding vertebrate and help to illuminate the evolution of social behaviour.</p> / Doctor of Philosophy (PhD)
23

ACOUSTIC COMMUNICATION IN THE JOINT-NESTING SMOOTH-BILLED ANI, CROTOPHAGA ANI

Grieves, Leanne A. 04 1900 (has links)
<p>I studied acoustic and visual communication in the Smooth-billed Ani, a joint-nesting, cooperatively breeding cuckoo. I describe vocal repertoire of this species using both qualitative and quantitative methods. In this first, formal description of the species’ repertoire, I provide verbal descriptions of each call type, the contexts in which each call is produced, spectrograms, and acoustic measurements for each call type. I used multivariate statistics to show that call types can be correctly classified based on acoustic measurements alone. Smooth-billed Anis are capable of complex communication, including the use of functionally referential alarms and signals of aggression that reliably predict attack. Functionally referential signals are produced in response to a specific set of stimuli and elicit predictable, appropriate responses in signal receivers, even in the absence of any other cues. I show that anis produce two distinct signal types, <em>chlurps</em> and <em>ahnee</em> <em>alarms</em>, in response to two different predator classes, aerial and terrestrial, respectively. I also show that receiver responses to playback of these alarm signals are distinct and appropriate to evade predation from aerial and terrestrial attackers. Aggressive signals should increase in aggressive contexts, predict subsequent aggression and elicit responses from signal receivers. I show that <em>hoots</em>, an acoustic signal, and throat inflation, a visual signal, both increase in aggressive contexts and reliably predict aggressive escalation in the form of direct attacks on a mount. The receiver response to <em>hoots</em> and throat inflation remains to be tested. In the synthesis, I provide suggestions for future research.</p> / Master of Science (MSc)
24

Attachment Style and Nonverbal Behavioral Synchrony in Romantic Couples

Olderbak, Sally January 2011 (has links)
Eshkol-Wachmann Movement Notation was applied to describe and quantify nonverbal behavioral synchrony between romantic partners. The interaction of 30 couples was observed across three study conditions, Pre-Stressor, and two Post-Stressor conditions when the female partner had been targeted with a stress manipulation. Participant-level behavior, and forms of dyadic synchrony were predicted with the male and females' self-reported attachment style. Results support theories from the attachment literature.
25

Territoriality and Spatial Structure in the Green Anole, Anolis carolinensis

Weber, William D, Jr. 16 December 2016 (has links)
Anolis carolinensis has been a model organism for ecology and evolutionary biology since the seventies, yet there are still understudied aspects of their ecology. A five-year study has provided microsatellite genotypes to be used in building a pedigree and assess relatedness, enabling us to evaluate the spatial distribution of an urban population of A. carolinensis. Results indicate no correlation between a male’s size and the distance others keep from it; however, males belonging in the heavyweight morph are dictating the spatial distribution in this population. In addition, juvenile dispersal of male offspring and partial philopatry of female offspring are key in this dynamic, where a single heavyweight male will actively defend a small area that contains multiple females, some of which are be daughters, and multiple unrelated males, most likely sneaker males.
26

Emergent Non-Consumptive Predator Effects Alter Habitat Colonization By Dipteran Prey

Staats, Ethan G 01 January 2015 (has links)
When ovipositing, prey organisms avoid habitat patches containing predator cues because predators consume, and negatively affect the fitness of their prey. Richness of predator species often enhances the strength of consumptive predator effects, but little is known about how multiple predators combined affect prey non-consumptively. We quantified dipteran colonization in aquatic mesocosms in response to varied predator richness. Multiple predator species combined reduced oviposition by Culex mosquitoes, chironomid midges, and the general colonizing dipteran community more than predicted by the effects of the independent predator species. Previous research which quantifies effects of multiple predators on prey as prey abundance, but does not measure consumption by predators, may be underestimating or overestimating the strength of effect by assuming equal colonization. Our findings enhance understanding of the ways predators influence abundances and distributions of their prey, and yields insight into the ways predators may non-consumptively affect prey by changing prey behavior.
27

Sledování mateřského chování samic u morčat / Observation of maternal behavior of females in guinea pigs

HOSPŮDKOVÁ, Hana January 2019 (has links)
The aim of this work was to find out and to evaluate the care of a mother and the brood of the Quinea pigs within 24 hours. Two groups of shorthaired Quinea pigs of the smooth breed were observed. The groups were composed of three females of the same age, where some of them were having brood. These individuals were filmed with a camera in a breeding facility. The video recordings were subsequently evaluated with using ethograms and after that with a verbal description of the mother's behavior while caring for her young animals. The recording of the different behavior in pre-prepared ethograms took 24-hours with one minute interval. This included also watching the breastfeeding, the coat caring of the brood, the female´s own feeding and drinking, the movements, the caring for their own hair, the rest (including the sleep), the lack of the interest in the young animals, and in one case also watching the interest of a mother in a dead young animal. In total, there were monitored three mothers in two steady groups. Where in the first group there was a mother (with brood) and two extra females. In the second group there were two mothers (with brood) with one extra female. The Guinea pigs belong to the animals that are caring for their brood since their birth. Throughout the observation period, no significant expelling of the young Guinea pigs was recorded. Until the breastfeeding was stopped, the mother looked after the brood with breastfeeding and with taking care of their coat. Even so, it was found out that most of the Quinea pigs are devoted to their own rest, which took them about half a day, 768 minutes (54 %). The breastfeeding took on average 170 minutes (12 %), however this care has ceased in the last observation. Taking care of the coat of the brood, which also has ceased in the last observation, took the females 15 minutes (1 %). Time spent with self feeding and drinking was 122 minutes (9 %). The female movements around the cage took on average of 306 minutes (21 %). The care for their own coat took 36 minutes (2 %). The expelling of the brood took on average 12 minutes (1 %).
28

Corte e aspectos da biologia reprodutiva do escorpião brasileiro Tityus bahiensis (Scorpiones: Buthidae) / Courtship and reproductive biology of the Brazilian scorpion Tityus bahiensis (Scorpiones: Buthidae)

Jorge, Sabrina Outeda 28 April 2010 (has links)
Os escorpiões são únicos dentre os artrópodes terrestres em muitos aspectos da biologia reprodutiva. A corte em escorpiões envolve sequências complexas de comportamentos ritualizados; é dividida em três fases: iniciação, dança e transferência de espermatozoides. Cerca de 50 espécies de escorpiões dentre as 1600 atualmente reconhecidas tiveram a corte descrita. Do mesmo modo, são poucos os estudos com tamanho de prole e investimento reprodutivo em escorpiões. Até o momento, a descrição da corte em Tityus bahiensis foi realizada com base em poucas observações incompletas. Os objetivos deste trabalho foram: estudar a corte em T. bahiensis para reconhecer os repertórios comportamentais e padrões de comportamento para espécie, através de um etograma e de um fluxograma; investigar prováveis funções das categorias comportamentais; abordar aspectos da época reprodutiva; e estudar o tamanho de prole, tempo de gestação e investimento reprodutivo. Dezenove cortes, de 202 pareamentos realizados, foram utilizadas para elaboração do etograma e do fluxograma. As sequências de comportamentos foram analisadas com o programa JWacher sup TM/sup e compiladas através de um script em Perl. Para o estudo do tamanho de prole, data de nascimento e período de gestação, foram compilados dados de 76 fêmeas. Desses nascimentos, 12 foram provenientes de cortes observadas em laboratório. A corte em T. bahiensis é complexa e está organizada de modo que a realização de uma fase prepara e condiciona o aparecimento da seguinte. A fase de iniciação tem funções como a procura por parceiros sexuais e o reconhecimento específico, sexual e da predisposição dos parceiros à corte. A fase de dança é dividida em dois módulos. No módulo I, o macho estimula e conduz a fêmea a uma superfície adequada para deposição do espermatóforo, preferencialmente uma casca de árvore (X2=24,314; g.l.=5; p<0,001). O módulo II apresenta comportamentos frequentes e repetitivos, com a função de estimular a fêmea e preparála para a fase seguinte. A fase de transferência de espermatozoides é rápida e estereotipada. Tem a função de inseminar e estimular a fêmea para uma cópula bemsucedida. Durante a cópula, o macho executa cortejo copulatório (tateamento com pernas e roçar com quelíceras). A fase de pós-transferência segue um padrão, mas apresenta poucas categorias, sendo que a maioria tem a provável função de romper o flagelo do espermatóforo inserido no gonóporo do macho; o macho pode consumir o espermatóforo e não ocorre canibalismo sexual. As fêmeas de T. bahiensis são capazes de controlar diferentes fases da corte obrigando os machos a utilizar comportamentos de estímulo, ao invés de coerção, para serem aceitos. A exibição de cortejo copulatório pelos machos é um forte indicativo da existência de seleção críptica feminina em T. bahiensis, sendo uma estratégia reprodutiva para estimular a fêmea a aceitar os espermatozoides do macho durante a aquisição do esperma. Apesar da época reprodutiva compreender o ano todo, os meses de maior atividade sexual são novembro a abril. O tamanho de prole na primeira parição é 2-25 filhotes (n=76). Além disso, T. bahiensis é capaz de produzir 1-4 proles com uma inseminação. O tempo de gestação é 2,5-12,8 meses e, apesar da capacidade de parir o ano todo, a maioria das parições ocorreu nos meses quentes, sobretudo, entre novembro e janeiro (X2=164,912; g.l.=11; p<0,001). Adicionalmente, o tamanho de prole é correlacionado com o tamanho corpóreo materno (rs=0,593; p=0,042; n=12). Assim, fêmeas maiores produzem mais filhotes e, portanto, apresentam maior investimento reprodutivo. / Scorpions are unique among terrestrial arthropods in many reproductive biology traits. Courtship involves a complex series of ritualized behaviors; it is divided into three phases: initiation, Promenade à deux, and sperm transfer. Courtship behavior has been described for about 50 of the 1600 extant scorpion species. Likewise, litter size and reproductive investment in scorpions are poorly known. Previous studies on Tityus bahiensis described courtship based on few and incomplete observations. The aims of this work were to study courtship behavior in T. bahiensis in order to recognize behavior repertories and behavior patterns for the species by making an ethogram and fluxogram; investigate probable functions of behavior categories; address aspects of the reproductive season; and study litter size, gestation period, and reproductive investment. Nineteen courtships, out of 202 interactions, were used to make the ethogram and the fluxogram. Behavioral sequences were analyzed with JWacherTM and compiled by a Perl script. For the study of litter size, date of birth, and gestation period, data of 76 females were compiled. Of these, 12 births were obtained from courtship observed in the laboratory. Courtship in T. bahiensis is complex and it is organized in a way that the execution of one phase prepares and regulates the appearance of the next. Initiation phase has functions such as the search for mating partner and species, sexual, and predisposition to court recognition. Promenade à deux phase is divided into two modules. In module I, male stimulates and leads female to a suitable surface for spermatophore deposition, preferentially a bark (X2=24,314; g.l.=5; p<0,001). Module II is characterized by frequent and repetitive behaviors, with the function of stimulating the female and preparing her to the next phase. Sperm transfer phase is rapid and stereotyped. Its function is to inseminate and stimulate the female for a successful mate. During mate, male executes copulatory courtship (feeling and kissing). Post transfer phase has a pattern, but with feel categories; most of them has the probable function of breaking the spermatophore flagellum inserted in the male gonopore; male may consume spermatophore, and there is no mating cannibalism. The females of T. bahiensis are capable of controlling different courtship phases, engaging males to use stimulating behaviors, rather than coercion, to be accepted. The exhibition of copulatory courtship by males strongly indicates the existence of cryptic female choice in T. bahiensis, being a reproductive strategy to stimulate the female to accept male spermatozoids during sperm uptake. Although reproductive season takes place all year long, the months in which reproductive activity is greater are throughout November to April. Litter size at the first parturition is 2-25 offspring (n=76). Moreover, T. bahiensis is capable of producing 1-4 broods with a single insemination. Gestation period is 2,5-12,8 months, and, although the capacity of giving birth throughout the year, most of the parturition occurred in the warm season, specially throughout November to January (X2=164,912; g.l.=11; p<0,001). In addition, litter size is correlated to female body size (rs=0,593; p=0,042; n=12). Thus, larger females produce more offspring and invest more into reproduction.
29

Documenting Marine Mammal Behavior and Evaluating the Benefits and Consequences of Viewing Marine Mammals in Southcentral Alaska

McCaslin, Lauren E. 01 July 2019 (has links)
Marine mammals are in a precarious conservation position because of anthropogenic impacts and historic perceptions that they are a consumable commodity. In light of changing abiotic conditions, further evaluation is needed on the habitat use, behavior, and interactions among marine mammals. Conservation legislation has helped protect species, but the greatest ground swelling may be the advent of the commercial whale watching industry. The feeding grounds in Alaskan waters have made this area a prime tourism location, and these nutrient-rich waters have resulted in a confluence of marine mammal species, including the appealing and abundant humpback whale (Megaptera novaeangliae) that may associate with three ecotypes of killer whales (Orcinus orca). These species are interesting because they may travel together to feed on prey or be adversaries in a predator-prey relationship. Using whale watching as a platform, this study evaluated the effects of the presence of these two species separately and together, and of the type of interaction between them, on human perception. Data were collected via opportunistic observations and a retrospective pre- and post-survey instrument. Differences in humpback whale distribution and group size patterns were found relative to killer whale occurrence, although humpback whale behavioral states were unchanged. Changes in passenger conservation attitudes could not be attributed to species and behaviors but they were important determinates to whale watching satisfaction. Overall, more positive conservation attitudes and an increase in knowledge about marine mammals were reported after whale watching. These tours provide an opportunity for collecting meaningful scientific data and providing more in-depth education such as enhancing the appreciation for ecosystem services provided by marine mammals.
30

Innovative environmental enrichment method for Pallas cat (<em>Felis manul)</em>

Rioldi, Emmanuela January 2010 (has links)
<p>Due to the expansion of the human population we are an increasing threat to all wild animals. They are driven to exist in smaller areas and in the worst case scenario extinction. Zoos are being encouraged to improve the animal’s physical and social surroundings. Environmental enrichment is a term used for such improvements. In this behavioural study, the enrichment introduced to two Pallas cats (<em>Felis manul</em>) at Parken Zoo in Eskilstuna, Sweden, consisted of a fishing rod and a clothes peg with a dead mouse or chick attached. The intention was to see if the feeding enrichment could increase activity levels and how the cats were using their enclosure. The enclosure was divided into seven zones which have a varying degree of opportunities for the animals to climb, hide and rest above ground level. The environmental enrichment effects on the Pallas cats´ behaviour, activity levels and use of the enclosure were measured and recorded using instantaneous scan sampling, and the mean value was calculated for each individual. The behavioural and enclosure results proved that enrichment benefits the cats activity levels. The behaviours that showed a variation when presented with enrichment were: walking, climbing, grooming, aggressive behaviour, out of sight behaviour, crouching position, sitting and standing still.  The results showed that the cats preferred the zones in the enclosure that offered a larger view of the nearby enclosures. This study shows that providing captive felids with inexpensive, easy to administer enrichment objects can have profound effects on activity behaviours and their enclosure.</p><p> </p>

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