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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.
11

Territorial relationships between Cardinals and Pyrrhuloxias

Gould, Patrick J. January 1960 (has links)
No description available.
12

Morphological variation in the Darwin's finches (Geospizinae) of Daphne Major Island, Galápagos

Boag, Peter T. January 1981 (has links)
A three year study on Daphne Major island, Galapagos, describes the ecology and morphology of a simple Geospiza community. The four part thesis discusses the breeding and feeding ecology of two Daphne finches; G. fortis is a generalist adapted to a variable environment, and G. scandens is an ecological specialist experiencing a more stable environment. The measurement, growth, allometry, and multivariate properties of seven external morphological characters are described. The repeatabilities and heritabilities of the seven characters and principal component scores are large. Relations between the unusual intermediate-sized Daphne G. fortis phenotype and the Daphne environment are examined. Four hypotheses for the intermediacy, including genetic drift, hybridization, local adaptation, and competition are suggested, with evidence found to support parts of each except genetic drift. An episode of intense directional natural selection is documented, and Lack's character release explanation of the Daphne G. fortis phenotype is revised.
13

Visual and behavioural influences on song tutor choice in Zebra finches (Taeniopygia guttata)

Mann, Nigel January 1992 (has links)
Using a laboratory approach, this thesis further' investigates patterns of song learning in the zebra finch (Taeniopygia guttata). Chapter 1 provides a background to the form and function of song learning in a broad context, and introduces the zebra finch and the major role it has played in this field of research. In Chapters 2 and 3, a strong influence of early visual imprinting on song tutor choice is demonstrated. Tutors of the same colour morph as the parents were much preferred. Song heard before or after the sensitive phase was often produced, if no tutor of the parental morph was present during this period. There was no clear evidence for one parent having a greater influence in this respect than the other. Differences were found between the morph preference for mates and song tutors, and possible reasons for these are discussed. Chapter 4 revealed that the mother may influence tutor choice, probably by attentiveness to her by her offspring increasing their exposure to the song of an accompanying male. There was also a preference for a paired, rather than a single, male. In Chapter 5, song tutor choice was studied in aviaries and related to behaviour occurring in this more naturalistic environment. A preference for learning the father's song was found). Specific types of interaction did not link overall with song copying, but the amount of time that birds spent within close proximity did. General aspects of behaviour evident in the aviaries are discussed. The final chapter demonstrated that a short distance (38 cm) between tutor and tutee can be sufficient to inhibit song learning, probably because of the reduced scope for interaction.
14

Morphological variation in the Darwin's finches (Geospizinae) of Daphne Major Island, Galápagos

Boag, Peter T. January 1981 (has links)
No description available.
15

Trade-offs between reproductive and somatic investment in male birds

Ferguson, Andrew John January 2000 (has links)
No description available.
16

The expansion of the eastern house finch population and its impact on populations of house sparrows, purple finches and American goldfinches

Hamilton, Thomas Robert January 1991 (has links)
Houses Finches became a breeding species in Indiana in 1981 and subsequently went through a rapid population increase. This study was an investigation of the growth of the House Finch population and its impact on House Sparrows, American Goldfinches and Purple Finches in Indiana. Data from the Annual Christmas Bird Counts of the National Audubon Society (CBC) were used to construct five winter range maps to show the expansion of the House Finch population since 1940. A population density map based on the CBCs of 1988 and 1989 was constructed using birds counted per party hour.CBC data collected during 1965 to 1989 at twelve locations in Indiana were used to track long-term changes in the populations of House Finches, House Sparrows, American Goldfinches and Purple Finches. The number of House Finches counted in Indiana since 1981 increased dramatically. The size of the House Sparrow population appears to have been in a long-term decline for the last 25 years. However, American Goldfinches have, in general, increased in abundance since 1979. The abundance of Purple Finches in Indiana in the winter varies erratically.Observations at backyard feeding stations frequented by House Finches and House Sparrows show that House Finches tend to displace other House Finches more often than would be expected if the displacements occurred in proportion to the frequency at which the birds appear in the population. House Sparrows were found to displace other House Sparrows at a rate which greatly exceeded the expected frequency based on their proportion of the population. Both species tend to avoid interspecific interactions.Field studies in Muncie, Indiana show that House Finches commonly nest in shrubbery and building decorations while House Sparrows often nest in crevices in old buildings and bird houses. No direct competition for nesting sites was observed.Banding studies indicate that during the fall and winter there is a constant turnover of House Finches in Muncie. Using banding data from the U. S. Fish and Wildlife Service it was found that House Finches in the Midwest tend to travel in a southern direction as the season changes from summer to winter and in a northern direction as the season changes from winter to summer. The study shows that House Finches have a strong propensity to return to the same general area each summer. / Department of Biology
17

REANALYZING THE ROLE OF ESTRADIOL IN THE DEVELOPING ZEBRA FINCH BRAIN

Musial, Andrea T. 05 December 2013 (has links)
No description available.
18

The ecology and moult of the Bullfinch

Newton, Ian January 1964 (has links)
No description available.
19

Personality in the City: Relationship Between Animal Behavioral Traits And Urbanization in a Fragile, Human-impacted Desert Ecosystem

January 2018 (has links)
abstract: Human-inhabited or -disturbed areas pose many unique challenges for wildlife, including increased human exposure, novel challenges, such as finding food or nesting sites in novel structures, anthropogenic noises, and novel predators. Animals inhabiting these environments must adapt to such changes by learning to exploit new resources and avoid danger. To my knowledge no study has comprehensively assessed behavioral reactions of urban and rural populations to numerous novel environmental stimuli. I tested behavioral responses of urban, suburban, and rural house finches (Haemorhous mexicanus) to novel stimuli (e.g. objects, noises, food), to presentation of a native predator model (Accipiter striatus) and a human, and to two problem-solving challenges (escaping confinement and food-finding). Although I found few population-level differences in behavioral responses to novel objects, environment, and food, I found compelling differences in how finches from different sites responded to novel noise. When played a novel sound (whale call or ship horn), urban and suburban house finches approached their food source more quickly and spent more time on it than rural birds, and urban and suburban birds were more active during the whale-noise presentation. In addition, while there were no differences in response to the native predator, rural birds showed higher levels of stress behaviors when presented with a human. When I replicated this study in juveniles, I found that exposure to humans during development more accurately predicted behavioral differences than capture site. Finally, I found that urban birds were better at solving an escape problem, whereas rural birds were better at solving a food-finding challenge. These results indicate that not all anthropogenic changes affect animal populations equally and that determining the aversive natural-history conditions and challenges of taxa may help urban ecologists better understand the direction and degree to which animals respond to human-induced rapid environmental alterations. / Dissertation/Thesis / Doctoral Dissertation Biology 2018
20

Historical Specimens Reveal a Century of Genetic Change in Darwin’s Finches

Farrington, Heather 19 April 2011 (has links)
No description available.

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