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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.
41

Environmental correlates of vocal communication of wild pygmy marmosets, Cebuella pygmaea

Torre, Stella de la. January 1900 (has links)
Thesis (Ph. D.)--University of Wisconsin-Madison, 1999. / Typescript. Includes bibliographical references.
42

Chemical communication : chemical characterization of volatile constituents of urine of the southern African cheetah, Acinonyx jubatus jubatus, using headspace sampling and GC-MS

Visser, Runine (Runine Cecile) 12 1900 (has links)
Thesis (MSc)--Stellenbosch University, 2002. / ENGLISH ABSTRACT: The cheetah, Acinonyx jubatus, sometimes referred to as "the greyhound of the cats", is probably the most elegant member of the cat family. Formerly widespread in southern Africa it is now threatened with extinction. It occurs in open savanna and light woodland, but also hilly country on occasion. The cheetah is a predator that can reach speeds of more then 110 km/h in short bursts. With a mass of between only 40 to 60 kg, it is not very powerful and cannot defend itself very effectively against carnivores such as the lion and hyaena, for example. This might be the reason why, in order not to advertise its presence, the urine of this animal is practically odourless. In turn, this might explain why no research has so far been devoted to the urine of this animal. In contrast extensive work has been done on the chemical characterisation of the urine of many other carnivores, notably the lion. Extraction of the urine with dichloromethane gave too little material for GC-MS. SPME sampling of the urine itself gave insufficient sample enrichment. Better results were obtained when an SPME-type of headspace sampling, using a larger mass of polydimethylsiloxane, was employed although many of the constituents of the urine could still barely be detected. The compounds identified include a large number of ketones, aldehydes, cyclic and acyclic ethers, carboxylic acids, amides two sulphur compounds in barely detectable quantities, and elemental sulphur. Perhaps the most remarkable result of this thesis is that it was found that the urine of the cheetah, although it is a carnivore, does not contain several sulphur compounds in relatively high concentrations. However, it does contain elemental sulphur. Perhaps a mechanism exists by which the cheetah can convert strongly odorous sulphur containing compounds into the less strongly smelling sulphur. / AFRIKAANSE OPSOMMING: Die jagluiperd, Acinonyx jubatus, 'n roofdier wat tydens 'n jagtog vir kort tye snelhede van meer as 110 km/h kan bereik, is waarskynlik die elegantste lid van die katfamilie. Met sy vaartbelynde liggaam weeg die dier egter slegs tussen 40 en 60 kg kan hy homself nie doeltreffend teen groter roofdiere verdedig nie. Chemiese verbindings, sogenaamde feromone, wat onder andere in die uriene uitgeskei word, word dikwels deur diere gebruik vir gebiedsafbakening en om met ander lede van die spesie te kommunikeer. Die uriene van die jadluiperd is egter feitlik reukloos. Tot dusver is die chemiese samestelling van die uriene van die jagluiperd nog nie ondersoek nie. Ekstraksie van die uriene met dichlorometaan het te min materiaal vir gaschromatografies-massaspektrometriese analise opgelewer, maar bevredigende resultate is verkry deur van 'n verbeterde monsternemingsmetode gebruik te maak. 'n Groot aantal organiese verbindings en twee swawelbevattende verbindings in skaars waarneembare hoeveelhede is in die uriene geïdentifiseer. Daar is egter 'n aansienlike hoeveelheid van die element swawel is in die uriene gevind. Laasgenoemde ontdekking, is die mees verbasende resultaat van hierdie navorsing. Die uitskeiding van swawel in uriene is, sover bekend, eenmalig in die soogdierwêreld. Dit is moontlik dat die jagluiperd oor 'n meganisme beskik om swawelverbindings wat baie sterk ruik om te sit na swawel wat nie so sterk ruik nie. Hierdie meganisme sal die dier se kanse op oorlewing verbeter deur van die swawelbevattende verbindings in sy dieet ontslae te raak sonder om sy teenwoordigheid in die omgewing te adverteer.
43

The evolution of semiochemicals in Australian marsupials

Zabaras, Regina, University of Western Sydney, College of Science, Technology and Environment, School of Science, Food and Horticulture January 2003 (has links)
The aim of this project was to study the nature and relative proportion of the volatile components in the sternal-gland secretions obtained from a wide range of Australian marsupials.The results obtained were then used to investigate the evolution of semiochemicals in Australian marsupials by using the current phylogenetic tree as a template.The initial part of the study was dedicated to the investigation of some of the techniques available for the sampling and analysis of gland secretions. Individuals from 8 families within the Marsupialia and 1 family from the Monotremata were sampled over an 18 month period.The obtained results were then subjected to multivariate statistical analysis followed by cladistic analysis.In several species the secretion composition was found to be affected by the breeding status of individuals for both genders.Many other factors such as animal-age, hierarchical status, diet,and lifestyle were also observed to affect the secretion composition. Finally, cladistic analysis demonstrated the differences in the levels of divergence at the species, familial and ordinal levels and highlighted secretion components that could be used to differentiate between super families, species and even sexual status of individuals. / Master of Science (Hons)
44

Infant cross-fostered chimpanzees develop indexical pointing

Nugent, Susie P. January 2006 (has links)
Thesis (M.A.)--University of Nevada, Reno, 2006. / "May 15, 2006." Includes bibliographical references (leaves 24-28). Online version available on the World Wide Web.
45

Structure and possible function of vocalizations of captive red-legged seriemas (Cariama cristata)

Padget, Ami Elizabeth 01 May 2010 (has links)
Very little is known about red-legged seriema (Cariama cristata) vocalizations and behavior. The focus of my research was to analyze the structure of red-legged seriema primary calls and to begin to test hypotheses related to their function. Captive red-legged seriema behavior, both vocal and non-vocal, was recorded at 7 institutions located in the United States from May 2007 through November 2008. To test whether calls serve a predator alarm function, seriemas were presented with a large stuffed dog, representing a predator stimulus, and 2 control stimuli, a large, stuffed penguin and a large, flowering potted plant. Baseline recordings with no manipulations were also made throughout the day, during the course of the study. All recordings of seriema vocalizations were assessed using sound analysis software to generate sound spectrograms for comparison. I identified three different note types within the seriema primary call: upsweep notes (U), ladder notes (L), and two-part notes (T). Each call begins with a set of U notes that increase in rate and lead into the main part of the call, which is made of L and T notes. Each note type was assessed for duration, frequency, energy, and entropy measurements. These measurements were reduced using factor analysis into two relevant factors. There were substantial differences across individuals for note type acoustic structure. Group differences in note types, including sex, location, and age, were not found. When presented with the dog model, vocal responses were given by only 3 individuals. Overall, it may be possible to identify individual seriemas by analyzing the structure of their primary call, which may allow researchers to identify individuals without physical markers.
46

Structure and possible function of vocalizations of captive red-legged seriemas (Cariama cristata)

Padget, Ami Elizabeth 01 May 2010 (has links)
Very little is known about red-legged seriema (Cariama cristata) vocalizations and behavior. The focus of my research was to analyze the structure of red-legged seriema primary calls and to begin to test hypotheses related to their function. Captive red-legged seriema behavior, both vocal and non-vocal, was recorded at 7 institutions located in the United States from May 2007 through November 2008. To test whether calls serve a predator alarm function, seriemas were presented with a large stuffed dog, representing a predator stimulus, and 2 control stimuli, a large, stuffed penguin and a large, flowering potted plant. Baseline recordings with no manipulations were also made throughout the day, during the course of the study. All recordings of seriema vocalizations were assessed using sound analysis software to generate sound spectrograms for comparison. I identified three different note types within the seriema primary call: upsweep notes (U), ladder notes (L), and two-part notes (T). Each call begins with a set of U notes that increase in rate and lead into the main part of the call, which is made of L and T notes. Each note type was assessed for duration, frequency, energy, and entropy measurements. These measurements were reduced using factor analysis into two relevant factors. There were substantial differences across individuals for note type acoustic structure. Group differences in note types, including sex, location, and age, were not found. When presented with the dog model, vocal responses were given by only 3 individuals. Overall, it may be possible to identify individual seriemas by analyzing the structure of their primary call, which may allow researchers to identify individuals without physical markers.
47

Social behavior and communication in a herd of captive giraffe

Bashaw, Meredith J., January 2003 (has links) (PDF)
Thesis (Ph. D.)--School of Psychology, Georgia Institute of Technology, 2004. Directed by Terry L. Maple. / Vita. Includes bibliographical references (leaves 213-226).
48

Behavioral endocrinology of female gray treefrogs, Hyla versicolor, in response to acoustic stimulation

Gordon, Noah M., Gerhardt, H. Carl. January 2008 (has links)
Title from PDF of title page (University of Missouri--Columbia, viewed on Feb 25, 2010). The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file. Dissertation advisor: Dr. H. Carl Gerhardt. Vita. Includes bibliographical references.
49

Sexual behavior, intraspecific signaling and the evolution of mimicry among closely related species

Estrada, Catalina, 1972- 16 October 2012 (has links)
Mimicry, an adaptation to deceive, fascinated early naturalist and has been proof of evolution by natural selection since proposed by Henry W. Bates 150 years ago. Yet, despite the abundant theoretical and empirical work that it has inspired, little is known of effects in intra and interspecific communication that might result from resembling phenotypic traits of sympatric species. In this dissertation research I studied sexual behavior and communication in Heliconius, a genus of diverse toxic butterflies with extraordinary convergence in wing coloration, habitat preferences and flight characteristics. Well-known ecological interactions and evolutionary history of Heliconius contrast with a poor understanding of key elements of their sexual behavior and intraspecific communication, which are central for the evolution of mimicry in this genus of butterflies. This thesis starts with an introduction that, expanding on the ideas above, explains the motivation behind studying sexual communication and behavior in Heliconius. In the subsequent four chapters I report on two aspects of sexual behavior that are presumably connected in these butterflies with the occurrence of mimicry: Pupal mating behavior and antiaphrodisiac pheromones. Pupal mating is a mate-searching strategy wherein males find females when still immature and guard them with the goal of mating at female eclosion. This mating behavior might have influenced the evolution of mimicry as males rely less on commonly used species recognition traits that in mimetic Heliconius are shared with coexisting species. I identified cues males use to find and recognize conspecific immatures, which not only come from the animal themselves but also from the host plant where they are located. Chemical and visual cues are involved in the process of finding partners, but only sex-specific pheromones allow males to identify females before their eclosion. The second aspect of sexual behavior studied in Heliconius involved the identification of a pheromone that, after being transferred to females at mating, renders them unattractive to courting males. Variation in the chemical composition of such antiaphrodisiacs across eleven species in this genus showed that, contrary to my expectations, there is no evidence that mimicry has affected the evolution of this signal. Instead, I found that clade-specific mating systems in these butterflies adequately explain the observed patterns of interspecific variation. / text
50

Communication in the weakly electric brown ghost knifefish, Apteronotus leptorhynchus

Triefenbach, Frank Alexander 28 August 2008 (has links)
Not available / text

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