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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

Os líticos de Lagoa Santa: um estudo sobre organização tecnológica de caçadores-coletores do Brasil Central / The lithics of Lagoa Santa: a study of hunters-gatherers technological organization from Central Brazil

Francisco Antonio Pugliese Junior 28 February 2008 (has links)
As relações entre a variabilidade e a variação dos conjuntos líticos de dois abrigos-sob-rocha do carste de Lagoa Santa - MG são analisadas em relação às estratégias de sobrevivência empregadas pelos grupos caçadores-coletores locais para lidar com as mudanças na disponibilidade de recursos no decorrer do Holoceno Inicial e Médio. Os processos de longa duração que atuaram na formação do registro arqueológico da Lapa do Santo e da Lapa das Boleiras são investigados através do estudo das continuidades e mudanças nas estratégias de procura, confecção, utilização e descarte dos materiais líticos. / The relationships between variability and variation in the lithic assemblages of two rock-shelters from Lagoa Santa are analyzed in respect to the survival strategies employed by local hunter-gatherers to deal with changes in resource's availability during the Early and Middle Holocene. The long-term processes involved in the formation of the archaeological record of Lapa do Santo and Lapa das Boleiras are investigated by the study of continuities and changes in the strategies to acquire raw materials and production, use and discard of lithic tools.
12

Ancient lipids reveal continuity in culinary practices across the transition to agriculture in Northern Europe

Craig, O.E., Steele, Valerie J., Fischer, Anders, Hartz, S., Andersen, S.H., Donohoe, P., Glykou, A., Saul, H., Jones, D.M., Koch, E., Heron, Carl P. January 2011 (has links)
Farming transformed societies globally. Yet, despite more than a century of research, there is little consensus on the speed or completeness of this fundamental change and, consequently, on its principal drivers. For Northern Europe, the debate has often centered on the rich archaeological record of the Western Baltic, but even here it is unclear how quickly or completely people abandoned wild terrestrial and marine resources after the introduction of domesticated plants and animals at approximately 4000 calibrated years B.C. Ceramic containers are found ubiquitously on these sites and contain remarkably well-preserved lipids derived from the original use of the vessel. Reconstructing culinary practices from this ceramic record can contribute to longstanding debates concerning the origins of farming. Here we present data on the molecular and isotopic characteristics of lipids extracted from 133 ceramic vessels and 100 carbonized surface residues dating to immediately before and after the first evidence of domesticated animals and plants in the Western Baltic. The presence of specific lipid biomarkers, notably omega-(o-alkylphenyl)alkanoic acids, and the isotopic composition of individual n-alkanoic acids clearly show that a significant proportion ( approximately 20%) of ceramic vessels with lipids preserved continued to be used for processing marine and freshwater resources across the transition to agriculture in this region. Although changes in pottery use are immediately evident, our data challenge the popular notions that economies were completely transformed with the arrival of farming and that Neolithic pottery was exclusively associated with produce from domesticated animals and plants.
13

The Distance from Necessity: A Bourdieusian Analysis of Gathering Practices in Vermont

Pierce, Alan Robert 13 January 2014 (has links)
No description available.
14

Optimal use of resources: classic foraging theory, satisficing and smart foraging – modelling foraging behaviors of elk

Weclaw, Piotr Unknown Date
No description available.
15

Optimal use of resources: classic foraging theory, satisficing and smart foraging modelling foraging behaviors of elk

Weclaw, Piotr 06 1900 (has links)
It is generally accepted that the Marginal Value Theorem (MVT) describes optimal foraging strategies. Some research findings, however, indicate that in natural conditions foragers not always behave according to the MVT. To address this inconsistency, in a series of computer simulations, I examined the behaviour of four types of foragers having specific foraging efficiencies and using the MVT and alternative strategies in 16 simulated landscapes in an ideal environment (no intra- and inter-species interactions). I used data on elk (Cervus elaphus) to construct the virtual forager. Contrary to the widely accepted understanding of the MVT, I found that in environments with the same average patch quality and varying average travel times between patches, patch residence times of some foragers were not affected by travel times. I propose a mechanism responsible for this observation and formulate the perfect forager theorem (PFT). I also introduce the concepts of a foraging coefficient (F) and foragers hub (), and formulate a model to describe the relationship between the perfect forager and other forager types. I identify situations where a forager aiming to choose an optimal foraging strategy and maximize its cumulative consumption should not follow the MVT. I describe these situations in a form of a mathematical model. I also demonstrate that the lack of biological realism and environmental noise are not required to explain the deviations from the MVT observed in field research, and explain the importance of scale in optimal foraging behaviour. I also demonstrate that smart foraging, which is a set of rules based on key ecological concepts: the functional response curve (FRC), satisficing, the MVT, and incorporates time limitations, should allow for fitness maximization. Thus, it should be an optimal behavior in the context of natural selection. I also demonstrate the importance of the FRC as a driver for foraging behaviors and argue that animals should focus more on increasing the slope of their FRC than on choosing a specific foraging strategy. Natural selection should, therefore, favor foragers with steep FRC. My findings introduce new concepts in behavioural ecology, have implications for animal ecology and inform wildlife management.
16

Communication chimique et régulations sociales dans la colonie d’abeilles (apis mellifera L.) / Chemical communication and social regulation in the honey bees colony (apis mellifera L.)

Maisonnasse, Alban 07 December 2010 (has links)
La colonie d’abeille (Apis mellifera L.) est une société complexe où les individus interagissent entre eux, notamment par le biais de phéromones. L’étude de cette communication chimique est indispensable à la compréhension des régulations sociales mises en place dans la colonie. Chez l’abeille, plus de 50 substances chimiques avec des effets incitateurs ou modificateurs sur la colonie ont été identifiées. Malgré ces découvertes, de nombreux travaux sont à accomplir pour mieux comprendre ce système de communication particulier.La problématique de cette thèse vise à caractériser l’histoire de vie d’une phéromone majeure l’Oléate d’Ethyle (EO), qui permet d’optimiser l’équilibre nourrices / butineuses dans la colonie. Parallèlement, d’autres recherches ont été entreprises, notamment l’étude de la communication chimique de la reine et du couvain, chez qui seulement deux phéromones ont été identifiées avec des effets pléiotropiques dans la colonie.Nos résultats ont mis en évidence une production variable d’EO par les ouvrières, en fonction de l’environnement de la colonie. La production de cette molécule chimique dans la colonie peut également être modifiée par un stress : des abeilles parasitées par du Nosema spp. ont une production anormalement élevée d’EO. En outre, cette molécule phéromonale est transmise des butineuses vers les nourrices par contact cuticulaire et par le pollen.Pour la compréhension de la communication entre la reine et les ouvrières, nos résultats montrent que la reine utilise d’autres composés phéromonaux puissant en redondance de la QMP pour orienter la construction de cire, le phénomène de cour et l’inhibition des ovaires des ouvrières.Chez le couvain, nous avons identifié un composé phéromonal volatil, le E-ß-ocimène, produit majoritairement par les jeunes larves, inhibant le développement des ovaires des ouvrières et accélérant leur maturation comportementale.Ces études nous ont permis d’avoir une connaissance plus précise de la communication chimique au sein de la colonie. Ainsi nous expliquons par deux théories le rôle de la complexité et de la redondance phéromonale de la colonie d’abeilles / In the honeybee colony (Apis mellifera L.) studies of the chemical communication are essential to understand social regulations. In the honey bee colony more than 50 chemical substances with releaser and primer effects have been identified. Despite years of research on this type of communication, significant work remains to be done.In this thesis, the aim is to characterize the dynamics of a major pheromone: ethyl oleate (EO), which optimizes the balance between nurses and foragers in the colony. In addition, we initiated research on the queen and brood chemical communication in which only two pheromones have been identified in the colony.We have demonstrated that EO production by workers varies under different colony environment. EO production can also be modified by stress; honey bees parasitized by the Nosema spp. have abnormally high EO production. In addition, we identified that EO is transmitted from foragers to nurses by contact (cuticle and pollen).For the queen, our results indicate that the queen uses multiple redundant pheromones (QMP and other unknown compounds), that affect wax construction, retinue behaviour and worker ovary inhibition.For the brood we have identified a volatile pheromone E-ß-ocimene produced mostly by the young larvae to inhibit the development of workers ovaries and accelerate workers’behavioural maturation.With these studies we clarify some aspects of what is known about chemical communication in the honey bee colony. Then we try to explain the role of complexity and redundancy of pheromones in the honey bee colony by two theories
17

Mountains as crossroads : temporal and spatial patterns of high elevation activity in the Greater Yellowstone ecosystem, USA

Reckin, Rachel Jean January 2018 (has links)
In the archaeological literature, mountains are often portrayed as the boundaries between inhabited spaces. Yet occupying high elevations may have been an adaptive choice for ancient peoples, as rapidly changing elevations also offer variation in climate and resources over a relatively small area. So what happens, instead, if we put mountain landscapes at the center of our analyses of prehistoric seasonal rounds and ecological adaptation? This Ph.D. argues that, in order to understand any landscape that includes mountains, from the Alps to the Andes, one must include the ecology and archaeology of the highest elevations. Specifically, I base my findings on new fieldwork and lithic collections from the Absaroka and Beartooth Mountains in the Greater Yellowstone Ecosystem (GYE) of the Rocky Mountains, which was a vital crossroads of prehistoric cultures for more than 11,000 years. I include five interlocking analyses. First, I consider the impacts of anthropogenic climate change on high elevation cultural resources, focusing on the diminishing resiliency of ancient high elevation ice patches and the loss of the organic artifacts and paleobiological materials they contain. Second, I create a dichotomous key for chronologically typing projectile points, suggesting a methodological improvement for typological dating in the GYE and for surface archaeology more broadly. Third, I use obsidian source data to consider whether mountain people were a single, unified group or were represented by a variety of peoples with different zones of land tenure. Fourth, I consider high elevation occupation in both mountain ranges as part of the seasonal round, using indices of diversity in tool types and raw material to study how the duration of those occupations changed through time. And, finally, I test the common contention that ancient people primarily used mountains as refugia from extreme climatic pressure at lower elevations. Ultimately, I find that, in both mountain ranges, increased high elevation activity is most highly correlated with increased population, not with hot, dry climatic conditions. In other words, the mountains were more than simply refugia for plains or basin people to occupy when pressured by climatic hardship. In addition, between the Absarokas and the Beartooths the evidence suggests two different patterns of occupation, not a monolithic pan-mountain adaptation. These results demonstrate the potential contributions of surface archaeology to our understanding of prehistory, and have important implications for the way we think about mountain landscapes as peopled spaces in relation to adjacent lower-elevation areas.
18

Foraging and menstruation in the Hadza of Tanzania

Fitzpatrick, Katherine January 2018 (has links)
The Hadza, residing near Lake Eyasi in northern Tanzania, represent one of the last remaining hunter-gatherer populations. Inhabiting the same area as our hominin ancestors and exploiting very similar resources, the Hadza maintain a foraging lifestyle characterised by a sexual division of labour. Studies of their foraging and food sharing habits serve as the foundation to numerous hypotheses of human behaviour and evolution. Data from the Hadza have featured heavily in debates on the sexual division of labour. These debates focus predominantly on men’s foraging, including how and why men provision. Women’s provisioning, on the other hand, is seldom explicitly examined and is often presumed to be constrained by reproduction. This thesis contributes to debates on the sexual division of labour by investigating how a woman’s reproductive status affects her foraging behaviours. Observational data on women’s foraging are investigated from 263 person/day follows (1,307 hours total) across 10 camps between 2004 and 2006. These data present the first quantitative documentation of forager women’s eating and sharing outside of camp. Interview data on women’s reproductive timeline are also analysed from in-depth interviews with 58 women from 9 camps in 2015. Spanning from menarche to menopause, these data offer the first quantitative and qualitative documentation of forager women’s menstruation. The results demonstrate that Hadza women eat and share over 800 kilocalories outside of camp per person/day. They regularly give and receive food, including gifts of honey from men. Breastfeeding women are more likely to give gifts and give more gifts than non-breastfeeding women. When they bring nurslings with them outside of camp, they forage less kilocalories per hour. Post-menopausal women eat less relative to what they forage, are less likely to receive gifts, rest less and forage more than pre-menopausal women. Although Hadza women describe their foraging workload as most difficult during late pregnancy, no significant differences in eating, sharing, resting or foraging are observed for pregnant women. Menstrual data from the Hadza reveal that menstruation is not only culturally relevant to the sexual division of labour, but it is also biologically relevant to current understandings of fertility. The majority (60%) of Hadza women report not doing their normal work during menstruation. They also report menstruation-related taboos for berry picking. The thesis presents an in-depth review of women’s menstruation, from the duration of menses to the menstrual cleaning process.

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