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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 wild man in the Spanish Renaissance and golden age theater a comparative study /

Mazur, Oleh, January 1966 (has links)
Thesis (Ph. D.)--University of Pennsylvania. / Description based on print version record. Includes bibliographical references (leaves xiii-xxxiv) and index.
52

Eastern wild turkey (Meleagris gallopavo silvestris) habitat preference and the impact of scratch foraging on hardwood regeneration in mixed oak forests

Rinkes, Zachary L. January 2004 (has links)
Thesis (M.S.)--Ohio University, March, 2004. / Title from PDF t.p. Includes bibliographical references (p. 22-27)
53

The biochemical analysis of southern African rhinoceros populations

O'Ryan, Colleen January 1993 (has links)
The drastic decline in the numbers of the five extant species of rhinoceroses world-wide, mainly as a result of poaching, have placed these species in imminent danger of extinction. This emphasizes the need to understand the relationships among the different species of rhinoceros. The advances in molecular biology have allowed the application of DNA-based genetic techniques to address a number of aspects of rhinoceros biology which have both academic interest and practical value to conservation management. There are four aspects to this study: Firstly, restriction endonuclease maps of mitochondrial DNA were constructed to estimate the time of divergence of Diceros bicornis (black rhinoceros) and Ceratotherium simum (white rhinoceros) from their common ancestor. Secondly, a population genetic study of the relationships among four subspecies of D. bicornis. Thirdly, the application of DNA fingerprinting to examine the intra- and inter-population relatedness in D. bicornis populations. Fourthly, a practical application of PCR to identify the origin of an unknown sample of DNA.
54

Microhabitat Use by Translocated Wild Turkeys in the Mississippi Delta

McKinney, Matthew Ryan 11 May 2013 (has links)
Eastern wild turkeys (Meleagris gallapavo silvestris) were extirpated from most of the Mississippi Alluvial Valley (MAV) by 1980 by overharvest and habitat loss. Federal programs have restored areas of the MAV to hardwood forest, potentially warranting restoring wild turkeys to the MAV. As part of a pilot restoration study, I gathered data on resource use and nest sites from July 2010–August 2011. I observed intraspecific niche specialization and spatial niche separation between genders. Spatiotemporal variation in resource availability and intraspecific competition appear to be factors influencing intraspecific niche specialization. Mature hardwood forest was primary habitat selected by translocated wild turkeys. Hardwood regeneration areas were primary habitat selected by hens for nesting. Visual obstruction from 0.0 m–0.5 m was important in selecting fine-scale nest sites. Hardwood regeneration areas have dual value for restoring wild turkeys to the MAV: future mature hardwood areas; and potential nest sites.
55

Miškinės obels ir miškinės kriaušės fenotipinis kintamumas / Phenotypic variability of wild apple and wild pear

Petrokas, Raimundas 27 July 2006 (has links)
Aim of the study – to evaluate the phenotypic variability of the wild apple and the wild pear in the aspect of the species’ natural regeneration and survival. The research sites have been chosen in the typical forest habitats of the species. The data on the mature trees were collected in the forests of south-western and central Lithuania in 1997-2005. The data on taxonomic identity of self-spreading pears were obtained after the evaluation of clone collection at the Lithuanian Institute of Horticulture. SAS and STATISTICA procedures were used for mathematical-statistical analysis of the data. With an aim to determine whether the wild apple may be able to produce viable apomictic seeds, seven progenies have been selected for peroxidase analysis according to the evaluation results of different female-trees at their natural habitats. The results of K-means clustering of pear clones were the sampling basis for peroxidase analysis of self-spreading pears. The novelty of the study is presented by: the evaluation of the phenotypic differences among trees at their natural habitats within the wild apple; the determination of the critical traits of the wild apple indicative for vigorousness of tree growth and survival; the determination of wild genotypes of the apple and the pear with the aid of peroxidase analysis for the first time in Lithuania; the definition of traits for taxonomic identification of self-spreading pears; the conceptualization of conservation and promotion of the... [to full text]
56

Writing Wounded Knee : representations of the 1890 massacre

Forsyth, Susan J. January 1998 (has links)
No description available.
57

Photosynthetic carbon and energy balance in tobacco : relation to phosphoribulokinase and phosphate

Pieters, Alejandro J. January 1999 (has links)
No description available.
58

Behavioural development in wild Western lowland gorillas (Gorilla gorilla gorilla)

Nowell, Angela A. January 2005 (has links)
Behavioural development has received little attention in primates, despite having important influences on infant mortality, interbirth intervals, and therefore, growth of populations. Gorillas have long developmental periods, exhibit strong maternal bonds and integrate into intricate social systems, making them an ideal species in which to investigate non-human primate development. Gorillas exist across a range of habitats, and differences in behaviour, both within and between species reflect socioecological differences, for example, in the availability and distribution of food. Consequently, by using gorillas as a model, opportunities also exist to investigate environmental constraints on the development of independence. This study provides the first detailed analysis, with reference to ecological factors, of the development of behavioural skills and relationships in wild western lowland gorillas (Gorilla gorilla gorilla). Behavioural development of western lowland gorillas is then compared with published accounts of development in mountain gorillas (Gorilla beringei beringei) to determine the extent to which differing ecology influences behaviour. The study was conducted at Mbeli Bai in the Republic of Congo, a large, marshy clearing, visited by gorillas predominantly for feeding purposes. Data were collected using scan, focal, all-occurrence and ad libitum sampling methods from 58 gorillas below 8 years of age. Spatial relationships, suckling, and the nature of interactions involving immature individuals were analysed. The distribution of time between different behaviours by immatures, and the development of independent feeding and travelling behaviour was also investigated, and all were tested for differences as a result of immature age, sex and social group, or the mother's parity. Towards the end of infancy, individuals showed competent feeding behaviour in the bai. However, western lowland gorillas were not weaned until the juvenile period, and until this time, close association was common between mothers and offspring. With increasing independence from the mother there was limited investment in relationships with other individuals, and instead, a greater emphasis was placed on developing skills through play, alloparenting and agonistic interactions. When results were compared with those of mountain gorillas, there was evidence of increased investment in relationships, particularly with the silverback, by immature mountain gorillas, which was assumed to reflect lower rates of natal dispersal by mountain gorillas, and the greater likelihood that relationships with individuals in the natal group could prove useful in the future. Suckling and close proximity to the mother continued until later ages in western lowland gorillas, resulting in clear differences between them mountain gorillas in the duration of investment by mothers. More frugivorous western lowland gorillas required increased levels of investment by the mother before independence could be achieved, demonstrating the effect that resource availability can have on behavioural development in species where resources are widely and unpredictably dispersed.
59

Carotenoid pigments as phenotypic tracers of salmonid life histories : studies on eggs, alevins and juveniles of trout (Salmo trutta L.) and sea lice of Atlantic salmon (Salmo salar L.)

Noack, Patrick T. January 1997 (has links)
The use of carotenoid pigments as an archive of feeding behaviour and thus as environmental markers was tested using eggs and juveniles of sea trout and brown trout (Salmo trutta L.) invertebrates from the River Don and ectoparasitic lice (Lepeophtheirus salmonis Kroyer) of Atlantic salmon (Salmo salar L.). Carotenoids were analysed by normal phase high performance liquid chromatography (HPLC) and the resulting peaks examined in multivariate analyses. Analysis of trout eggs of known parentage suggested that the pigment profile of each egg reflects the migratory history of the maternal fish and it is also representative of the entire egg batch. With the same method, eggs of unknown or disputed parentage could be identified as those of sea trout, brown trout or salmon. Diagnostic properties permitting identification were high amounts of astaxanthin in sea trout eggs; while the presence of lutein, zeaxanthin and a greater number of carotenoid peaks were indicative of brown trout eggs. In hatchery experiments it was established that the diagnostic maternal pigment fingerprint is identifiable for some 1300°d post fertilisation. In this time the majority of carotenoids are metabolised to astaxanthin esters and exogenous feeding will have begun. Muscle tissue carotenoids of juvenile trout in the River Don clearly separated 0+ trout from 1+ fish. The former arrange in a single discrete cluster on the basis of pigmentation, suggesting a common diet throughout the river catchment. Older parr show a specialist diet typical to each region but different from fry, indicating a shift in diet acquisition throughout early life stages. Pigment analysis of stream-living invertebrates and one terrestrial invertebrate revealed that all, except the terrestrial ear-wig, Rhabdiopteryx sp., Gammarus sp. and Leuctra sp., provide a homogeneous pigment profile. In contrast, Gammarus sp. was found to be the supplier of the greatest relative amount of astaxanthin, lutein and zeaxanthin. The diagnostic potential of carotenoids in sea lice was explored in samples taken from wild and farm Atlantic salmon fed on an artificial diet. Astaxanthin and canthaxanthin, which are pigments diagnostic of a natural and synthetic diet respectively, were detected. The ratio of canthaxanthin-like pigment to astaxanthin (C:A ratio) was 45:1 in farm lice and 8:1 in wild lice. Carotenoid content therefore could potentially be used as a tracer of origin of sea lice in epidemiological investigations.
60

A cognitive approach to the study of culture in wild chimpanzees (Pan troglodytes schweinfurthii)

Gruber, Thibaud January 2011 (has links)
The question of animal culture has been of interest for decades. Chimpanzees (Pan troglodytes) have played a key role in the debate of whether or not it is appropriate to use the term ‘culture' to describe animal behaviour and they continue to be one of the prime species for the study of the origins of human culture. Data suggesting that chimpanzees can be considered a cultural species continue to accumulate, but this has only enhanced the debate between proponents and opponents of animal culture. Opponents do not deny that behavioural diversity exists between different populations of the same species, but they maintain that such phenomena have little to do with human cultures and may be the result of genetic and environmental influences. In their view, human cultures are centred on socially shared sets of ideas, not behavioural traditions. In this thesis, my goal is to tackle this problem and to investigate whether a cognitive dimension can be found in some behavioural patterns of chimpanzees that have been put forward as examples of animal culture. To this end, I examine the different factors that could account for the development of tool use in animals (genetics, ecology, social). My first empirical contribution is a study of the tool use behaviour of the chimpanzees' closest relative, the bonobos, which are known to be limited tool-users in the wild. I show that captive bonobos are as flexible tool-users as chimpanzees, suggesting that genetic factors are unlikely to account for differences in tool use behaviour in the Pan clade. Second, through the use of field experiments, I show that wild chimpanzees from different Ugandan communities respond to the same apparatus and task in strikingly different ways. I interpret this finding as an outcome of differences in cultural knowledge, mainly because the affordances of their immediate environment do not determine their tool use behaviour. Finally, through a broad ecological and tool use survey of different chimpanzee communities in Uganda, I show that current ecological differences are poor predictors of tool use. I conclude that, if ecology plays a role in the development of tool use, then its influence is that of a selective force. Finally, when reviewing the outcome of this research I will argue that there is a profound cognitive dimension to tool use in wild chimpanzees, suggesting that behaviourally based definitions of animal culture may miss a key feature of the phenomenon, at least in chimpanzees. Chimpanzees are not only a cultural species, they also have a cultural mind.

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