This dissertation explores the inter-relatedness of lithic technology and human mobility in the ancient central North American Arctic. Palaeo-Eskimo populations inhabited southeastern Victoria Island, Nunavut, discontinuously for over three thousand years. During this time, Palaeo-Eskimo lifeways are believed to have changed significantly in regards to subsistence economy, settlement patterns, interaction patterns, and mobility. One of the most significant changes is a marked decrease in the scale and frequency of human mobility and an increase in the re-occupation of seasonal camps. Palaeo-Eskimo material culture is observed to undergo important changes at the same time; consequently, one wonders what influence(s) mobility may have effected on the form and nature of Palaeo-Eskimo material culture. This work examines the potential influence of human mobility on lithic technology in the Pre-Dorset, Early Dorset, and Middle Dorset periods as evidenced by lithic assemblages from nine archaeological sites and site components in the Iqaluktuuq (Ekalluk River) region of Victoria Island. Over 800 formal tools and 30000 pieces of debitage were examined and analyzed according to two interpretive frameworks: one technological and the other mobility-related. The technological analyses demonstrate that significant changes took place in lithic production and maintenance processes during the Palaeo-Eskimo period. The mobility-related analyses demonstrate that, while many of the changes to lithic technological organization are consistent with expected trends resulting from a decrease in human mobility, not all aspects of Palaeo-Eskimo lithic tool production, maintenance and use appear to have been similarly influenced by this change in mobility.

This dissertation explores the inter-relatedness of lithic technology and human mobility in the ancient central North American Arctic. Palaeo-Eskimo populations inhabited southeastern Victoria Island, Nunavut, discontinuously for over three thousand years. During this time, Palaeo-Eskimo lifeways are believed to have changed significantly in regards to subsistence economy, settlement patterns, interaction patterns, and mobility. One of the most significant changes is a marked decrease in the scale and frequency of human mobility and an increase in the re-occupation of seasonal camps. Palaeo-Eskimo material culture is observed to undergo important changes at the same time; consequently, one wonders what influence(s) mobility may have effected on the form and nature of Palaeo-Eskimo material culture. This work examines the potential influence of human mobility on lithic technology in the Pre-Dorset, Early Dorset, and Middle Dorset periods as evidenced by lithic assemblages from nine archaeological sites and site components in the Iqaluktuuq (Ekalluk River) region of Victoria Island. Over 800 formal tools and 30000 pieces of debitage were examined and analyzed according to two interpretive frameworks: one technological and the other mobility-related. The technological analyses demonstrate that significant changes took place in lithic production and maintenance processes during the Palaeo-Eskimo period. The mobility-related analyses demonstrate that, while many of the changes to lithic technological organization are consistent with expected trends resulting from a decrease in human mobility, not all aspects of Palaeo-Eskimo lithic tool production, maintenance and use appear to have been similarly influenced by this change in mobility.

The sites of Elandsfontein (EFT) and Duinefontein (DFT) preserve important records of mid-Pleistocene human occupation along South Africa's southwestern coast. In addition to human fossils in the case of EFT, both sites have produced extensive collections of artefacts and faunal remains. Analyses of the latter have provided the broad environmental contexts for mid-Pleistocene human occupation along this coast. Recently, research into landscape use by mid-Pleistocene human populations at EFT and DFT has highlighted the need for more precise palaeoenvironmental data for the region. In response to this need, I analysed plant phytoliths extracted from sediments sampled at EFT and DFT. The results of this analysis are reported and interpreted in this thesis. To assist with the interpretation of the EFT and DFT phytolith assemblages, I established a modern phytolith reference collection. In addition, pre-existing phytolith collections were examined and literature was consulted. Phytoliths extracted from modern and mid-Pleistocene aged sediments sampled at different localities at EFT and DFT were identified and tallied to determine vegetation composition during the middle Pleistocene. Distinctions were made between "grassier" and "more woody" samples. Analyses of modern plant samples confirmed that grass species produced abundant phytoliths, whereas the majority of dicotyledons did not produce diagnostic morphotypes. Phytoliths belonging to grass species currently growing in the region were identified in the modern sediment samples, as were non-grass phytoliths that included those from woody dicotyledonous and monocotyledon plants. The majority of the mid-Pleistocene sediment samples from EFT produced varying proportions of grass, woody dicotyledon, monocotyledon, sedge and palm type phytoliths which are characteristic of cool-season growing landscapes. In comparison to EFT, the late mid- Pleistocene sediment samples from DFT contained fewer phytoliths. These results suggest that the conditions at DFT were either not conducive to the preservation of phytoliths or that the vegetation was sparse and/or did not produce abundant phytoliths. Where sufficient phytoliths were preserved, assemblages suggested landscapes similar to that of EFT. In summary, analyses suggest that during the middle to late Pleistocene, a heterogeneous vegetation community, consisting primarily of C₃ grasses, woody dicotyledons and other monocotyledonous plants existed along South Africa's southwest coast. Furthermore, results support the longterm presence of the winter rainfall zone in the region. This study demonstrates the potential of phytolith analysis as an important proxy in determining the composition of palaeo-vegetation communities in South Africa. Although there were limitations that necessitated the broad classification of phytolith groups, the study nevertheless provided more precise information, particularly about mid-Pleistocene vegetation structure, that was not previously available.

La transition entre le dernier épisode glaciaire et l'actuel interglaciaire (de 20 000 à 10 000 ans avant le présent) est caractérisée par de courtes et abruptes réorganisations du climat à différentes échelles. Sur l'Altiplano bolivien des paléolacs géants se développent et disparaissent en moins de 2000 ans. La dynamique des glaciers étant contrôlée par le climat, les dépôts laissés par les anciens glaciers constituent une des rares archives climatiques disponibles sur ce haut plateau aride. La méthode des âges d'exposition permet de reconstituer l'histoire des anciens glaciers. Cette thèse apporte de nouveaux outils méthodologiques pour le calcul de ces âges. Elle présente également de nouveaux âges couplés à des reconstructions climatiques. Ces résultats indiquent que la formation des paléolacs est concomitante de refroidissements moyens compris entre 2.5 et 4.5 C par rapport au présent et d'un apport accru d'humidité depuis l'Est, franchissant la Cordillère Orientale bolivienne / The transition between the last glacial maximum and the actual interstadial (from 20 to 12 ka before present) is characterized by short and abrupt climate reorganizations at different scales. Over the Bolivian Altiplano, giant palaeo-lakes wax and wane within 2000 years. The glaciers dynamics is controlled by the climate, making the deposits from the former glaciers one of the few climatic archives available on this arid plateau. The exposure age method enables to reconstruct the history of former glaciers. This thesis brings new tools for the calculation of these ages. It also presents new ages coupled with palaeo-climate reconstructions. These results indicates that the palaeo-lake formations are concomitant with mean coolings of 2.5 to 4.2°C compared to present and with an enhanced moist transport from the East, crossing the Bolivian Oriental Cordillera

Free and open source geographic information systems (GIS) and spatial data are readily available to use in spatial-archaeological problem solving. Greater accessibility allows more frequent experimentation with archaeological GIS methodologies. The least cost path (LCP) analysis has been a frequently used method in archaeological GIS. Showing potential mobility patterns between archaeological sites or between sites and resources has been the LCP’s primary objective. The LCP’s major flaw is that is must be calculated between two designated points. A recent terrain analysis of southern Baffin Island has been unable to overcome this flaw, because of the size of the study area and the inability to assume any two points are directly related. Thus, a new GIS method using a ‘watershed’ function has been manipulated to incorporate the cost-surface element of the LCP into a mobility model by generating pathway networks instead of narrow A to B paths. The product is a multitude of potential pathways linking archaeologically dense coastal and interior areas. Portions of these pathways correlate with historic geographic descriptions of Inuit travel routes and with areas where chert toolstone is accessible. Generated with no material cost, this analysis has produced a predictive model to help in future research.

<p>This thesis presents a palaeoglaciological study aimed to determine the location, geometry and temporal evolution of palaeo-ice streams of the north-easternmost Laurentide Ice Sheet. The work was accomplished through the geomorphological interpretation of satellite imagery over 3.19 x 10⁶ km² of the Canadian Arctic, using a glaciological inversion scheme. Ice streams were active in this region during most of the time between the Last Glacial Maximum and the last deglaciation. A web of ice streams and inter-ice stream areas existed. Three major ice stream networks are identified: the M'Clintock Channel, Gulf of Boothia – Lancaster Sound and Hudson Strait. The M'Clintock Channel bears the most complex landform record, comprising three generations of palaeo-ice streams. Their location was weakly controlled by the subglacial topography and their geometry was determined by frozen-bed portions of the ice sheet, thus providing evidence for pure ice streams in the Laurentide Ice Sheet. In contrast, the more pronounced relief of the Gulf of Boothia – Lancaster Sound corridor supported topographically controlled ice streams. The landform record on emerged land along Hudson Strait is insufficient to support the existence of ice streams. It is therefore proposed that ice streams were constrained within the deep parts of the strait while flanked by cold-based zones on the margins. Small transient ice streams on Baffin and Prince of Wales islands drained local remnant ice caps during the collapse of the ice sheet. Analysis of the controls on the location and flow of palaeo-ice streams suggests that the interaction between the subglacial topography and thermal state of the substrate plays a more fundamental role than the geology. It is concluded that the behaviour of ice streams cannot be explained in terms of environmental controls alone, but the complex dynamics of ice stream shear margins and onset zones must be considered.</p>

This thesis presents a palaeoglaciological study aimed to determine the location, geometry and temporal evolution of palaeo-ice streams of the north-easternmost Laurentide Ice Sheet. The work was accomplished through the geomorphological interpretation of satellite imagery over 3.19 x 106 km2 of the Canadian Arctic, using a glaciological inversion scheme. Ice streams were active in this region during most of the time between the Last Glacial Maximum and the last deglaciation. A web of ice streams and inter-ice stream areas existed. Three major ice stream networks are identified: the M'Clintock Channel, Gulf of Boothia – Lancaster Sound and Hudson Strait. The M'Clintock Channel bears the most complex landform record, comprising three generations of palaeo-ice streams. Their location was weakly controlled by the subglacial topography and their geometry was determined by frozen-bed portions of the ice sheet, thus providing evidence for pure ice streams in the Laurentide Ice Sheet. In contrast, the more pronounced relief of the Gulf of Boothia – Lancaster Sound corridor supported topographically controlled ice streams. The landform record on emerged land along Hudson Strait is insufficient to support the existence of ice streams. It is therefore proposed that ice streams were constrained within the deep parts of the strait while flanked by cold-based zones on the margins. Small transient ice streams on Baffin and Prince of Wales islands drained local remnant ice caps during the collapse of the ice sheet. Analysis of the controls on the location and flow of palaeo-ice streams suggests that the interaction between the subglacial topography and thermal state of the substrate plays a more fundamental role than the geology. It is concluded that the behaviour of ice streams cannot be explained in terms of environmental controls alone, but the complex dynamics of ice stream shear margins and onset zones must be considered.

La cité d'Alexandrie s'est développée sur un cordon littoral étroit, baigné au sud par le Maryut, lagune du delta du Nil qui s'est trouvée ainsi au coeur de l'économie industrielle et commerciale de la cité et de son arrière-pays depuis l'antiquité jusqu'à aujourd'hui. Dans ce riche contexte géo-archéologique, l'objectif de cette thèse de géomorphologie littorale a été de proposer une clef de lecture environnementale de l'histoire de l'occupation de la région du Maryut. L'analyse bio-sédimentologique des archives sédimentaires datées au radiocarbone, ainsi que la mesure du rapport isotopique du strontium dans des coquilles d'ostracode ont été utilisées pour reconstituer l'évolution hydrologique et géographique de la lagune à l'Holocène. La dépression du Maryut est transgressée par la mer vers 7,5 ka cal. BP. Les apports du Nil deviennent ensuite progressivement dominant dans le budget hydrologique, parallèlement à la progradation du littorale deltaïque. A partir de 5,5 ka cal. BP, nos données décrivent le retour progressif de conditions marines dominantes, associées à la réduction des débits du Nil, dans le contexte de la terminaison de la Période Africaine Humide. Cette lagune marine apparaît pérenne jusque 3ka cal BP, puis, dans le courant du 3ème millénaire BP, les intrants nilotiques redeviennent prépondérant. Ensuite, les archives sédimentaires et les données historiques disponibles décrivent une histoire environnementale contrastée est apparue corrélée à des phases de dynamisme et de récession agricole et met en évidence, selon nous, l'impact croissant des pratiques d'irrigation sur le fonctionnement du Maryut, situé en terminaison de la chaîne hydraulique. / The ancient city of Alexandria was founded upon a narrow beach ridge, washed by the Maryut to the south. This Nile delta lagoon has been at the heart of the industrial and commercial economies of the city from Antiquity through to present day. Against the backdrop of this rich geoarchaeological context, the aim of this coastal geomorphology thesis is to elucidate the environmental history of the Maryut region.We have reconstructed the hydrological and geographical evolution of the lagoon during the Holocene using: (1) bio-sedimentology of radiocarbon-dated sediment archives; and (2) strontium isotopes in ostracod shells. The Maryut basin was transgressed by the sea around 7.5 ka cal. BP. Progressively, Nile inputs became dominant in the lagoon's hydrological budget, concomitant with the coastal progradation of the delta. After 5.5 ka cal. BP, our data attest to a gradual return to dominant marine conditions, which we link to a reduction in Nile flow in the context of the end of the African Humid Period. This marine lagoon seems to have been perennial until 3 ka cal. BP before Nile inflow became dominant, from the 3rd millennium BP until 0.8-0.9 ka cal. BP. The sediment archives and the historical data support an important retraction of the waterbody around 1 ka cal. BP, recorded by evaporite deposits. This was followed by a new highstand around 0.7 ka cal. BP before a retraction centred on 0.3-0.2 ka cal. BP. Since around 2000 years, this contrasting environmental history is correlated with phases of agriculture peaks and recessions and shows the increasing impact of irrigation practices on the functioning of the Maryut, located at the end of the hydrological conveyor.

The objective of this research is to interpret high-resolution palaeo-proxy data sets to understand the Asian summer monsoon variability in the past. This was done by synthesizing published palaeo-records from the Asian monsoon region, model simulation comparisons, and analysing new lake sedimentary records from northeast Thailand. Palaeo-records and climate modeling indicate a strengthened summer monsoon over Mainland Southeast Asia during the Last Glacial Maximum (LGM), compared to dry conditions in other parts of the Asian monsoon region. This can be explained by the LGM sea level low stand, which exposed Sundaland and created a large land-sea thermal contrast. Sea level rise ~19 600 years before present (BP), reorganized the atmospheric circulation in the Pacific Ocean and weakened the summer monsoon between 20 000 and 19 000 years BP. Both the Mainland Southeast Asia and the East Asian monsoon hydroclimatic records point to an earlier Holocene onset of strengthened summer monsoon, compared to the Indian Ocean monsoon. The asynchronous evolution of the summer monsoon and a time lag of 1500 years between the East Asian and the Indian Ocean monsoon can be explained by the palaeogeography of Mainland Southeast Asia, which acted as a land bridge for the movement of the Intertropical Convergence Zone. The palaeo-proxy records from Lake Kumphawapi compare well to the other data sets and suggest a strengthened summer monsoon between 10 000 and 7000 years BP and a weakening of the summer monsoon thereafter. The data from Lake Pa Kho provides a picture of summer monsoon variability over 2000 years. A strengthened summer monsoon prevailed between BC 170-AD 370, AD 800-960 and since AD 1450, and was weaker about AD 370-800 and AD 1300-1450. The movement of the mean position of the Intertropical Convergence Zone explains shifts in summer monsoon intensity, but weakening of the summer monsoon between 960 and 1450 AD could be affected by changes in the Walker circulation. / <p>At the time of the doctoral defense, the following paper was unpublished and had a status as follows: Paper 4: Manuscript..</p>

L’archéologie de l’Arctique canadien, bien qu’ayant fait une large place à certaines catégories d’objets, telles les têtes de harpon, n’a encore que peu exploité la grande richesse informative des objets en matières dures d’origine animale. Une périodisation typologique a été réalisée sur l’ensemble de la période du Paléoesquimau (~ 4000-500 B.P.), classiquement subdivisée en Prédorsétien et Dorsétien au Canada. Les pratiques techniques et économiques des Paléoesquimaux ont été abordées à partir de l’étude de six sites localisés autour du Golfe de Foxe, région centrale pour l’archéologie arctique : région d’Igloolik (Parry Hill, Lyon Hill, Jens Munk, Freuchen et Kaersut) et nord du Nunavik (Tayara). Les données typologiques et technologiques obtenues permettent de confirmer l’existence d’un continuum culturel entre Prédorsétien et Dorsétien. L’évolution des industries en matières dures d’origine animale observée, notamment au moment du passage du Prédorsétien au Dorsétien, a été interprétée en termes de changements socio-culturels. Un fait marquant serait l’apparition des têtes de harpon à logette partiellement fermée, contemporaine d’une intensification de l’exploitation du morse, témoignant de chasses désormais collectives qui auraient incité les chasseurs à séjourner désormais ensemble dans des habitations plus grandes, occupées sur de plus longues périodes. / The studied ivory, bone and antler artifacts from the Canadian Arctic, only correspond to harpoon heads that served to build the Palaeo-Eskimo chronology (~ 4000-500 B.P.). To ascertain the chronological subdivision between the Pre-Dorset and Dorset cultures a typological study associated with a technological approach was performed. Palaeo-Eskimo technological and economical practices have been derived from the study of six sites located around the Foxe Basin: Igloolik region (Parry Hill, Lyon Hill, Jens Munk, Freuchen and Kaersut sites) and northern Nunavik (Tayara site). The assumption of a Pre-Dorset/Dorset continuum could be confirmed. The observed evolution of osseous industries during Palaeo-Eskimo period (and more precisely the Pre-Dorset/Dorset transition) has been interpreted in terms of socio-cultural changes. The observed technological changes (i.e. harpoon head hafting) could be associated with new patterns of raw material exploitation (diversification in the selection of materials and anatomical elements, as well as functional categories). They testify to the important socio-cultural changes (collective rather than individual hunting) already observed in the settlement patterns (aggregation of the humans in larger houses for longer time periods).