Understanding the level of biological connectivity among populations of harvested species is an important step towards establishing fisheries management and conservation guidelines. Many marine benthic resources present a complex metapopulation structure in which separate subpopulations of sessile post-larval individuals are connected through larval dispersal. The extent to which these subpopulations are linked is termed connectivity and can have different patterns and implications. Therefore, good management practices require tools that explicitly acknowledge this complexity across scales.I investigated the level of connectivity in a commercially important benthic species, the rock scallop (Spondylus calcifer), in an ecologically sensitive region in the NE margin of the Gulf of California, Mexico. My approach involved the development of a predictive coupled biological-oceanographic model (CBOM), which simultaneously incorporated key oceanographic and biological features. I validated CBOM outputs by means of two different techniques: population genetics analysis and measurements of spat abundance on artificial collectors.In order to infer the planktonic period of S. calcifer larvae to be used as an input for the model, I studied the early life history of the species under laboratory conditions. I estimated that the minimum period for larvae of S. calcifer to reach the settlement is approximately 15 days after fertilization. In addition to providing information useful for the model, this study produced information about the experimental conditions under which spawning induction and rearing of the species can be successful.I found strong connectivity along the study region (covering approximately 300 km of coastline). Sampled localities showed low levels of genetic structure, suggesting the existence of two subtly differentiated genetic populations. Both genetic and CBOM spatial scales of connectivity are in agreement suggesting that, on average, connectivity between subpopulation decreases when the geographic distance between them is >100 km.This study provides a multidisciplinary approach to evaluate the direction, magnitude and spatial scale of larval dispersal and connectivity, with implications for fisheries management and conservation in the study region. More broadly, it provides a baseline for future studies on coastal connectivity at various spatial scales of interest in the Gulf of California and beyond.

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I address the emergence, governance, and effects of marine reserve efforts in the Gulf of California, Mexico, emphasizing a community-based marine reserve network established by the commercial diving sector of Puerto Peñasco, Sonora. This network emerged as a means to manage benthic resources in rocky reefs, primarily rock scallop (Spondylus calcifer) and black murex snail (Hexaplex nigritus). My study also provides an analysis of growth, reproductive ecology, and management of both species.I show that local cooperation to manage fisheries commons incorporating the use of marine reserves can emerge rapidly. Furthermore, this cooperation can be sustained in a fishery spanning no more than two generations, effectively avoiding a local "tragedy of the commons". A blend of social group characteristics, fishers' ecological knowledge and participation in monitoring, and relatively rapid ecological response of the system can play key roles in reinforcing cooperation.I provide evidence of rapid effects of reserves on adjacent fisheries via larvae dispersal. Visual censuses revealed that density of young rock scallop (individuals recruited since reserve establishment) had increased by up to 40.7% within coastal reserves and by 20.6% in fished sites in only two years. Changes were also evident for black murex, with more than a three-fold increase in the density of juveniles within fished sites. These effects, however, were spatially-constricted, evident only for the northern portion of the reserve network. These empirical findings are more indicative of a reserve effect rather than other confounding factors and are consistent with field oceanography data (release of satellite-tracked drifters) and outputs from larvae dispersal models.Finally, I show that just as cooperation can emerge, it can rapidly fall with cascading effects to the system's resilience, particularly amidst threats to social capital and pressure from outside the community. I conclude that even when community-based reserves are effective within the biophysical and local social context, their long-term efficacy will rely on the system's capacity to control access and will demand the institutional capacity to do so. In Mexico this implies, at the least, the government's formal recognition of community-based initiatives and a means to give viability to these efforts.

<p>This thesis examines the Neolithic settlements in Durankulak, Danube, north of Bulgaria and Sitagroi in Greek Macedonia at the time when human life went from nomadic and hunting to well organized, agriculture and settled. As a background I present facts about the chronology, I will look for similarities and differences in the climate and the environment of the settlements and then I make a comparison based on the material findings. The facts, analyses and artefacts give a base for understanding the daily life in Durankulak and Sitagroi. By comparing the settlements I will investigate if the Neolithization was a homogenous process on Balkan or if there are differences that indicate external inputs from several directions.</p>

This thesis examines the Neolithic settlements in Durankulak, Danube, north of Bulgaria and Sitagroi in Greek Macedonia at the time when human life went from nomadic and hunting to well organized, agriculture and settled. As a background I present facts about the chronology, I will look for similarities and differences in the climate and the environment of the settlements and then I make a comparison based on the material findings. The facts, analyses and artefacts give a base for understanding the daily life in Durankulak and Sitagroi. By comparing the settlements I will investigate if the Neolithization was a homogenous process on Balkan or if there are differences that indicate external inputs from several directions.

Les rituels d’appel à la pluie, du nettoyage des canaux d’irrigation et du marquage du bétail sont analysés et reconstitués à l’aide d’un modèle qui utilise les sources ethnographiques, ethnohistoriques et archéologiques disponibles. Ce modèle permet une approche interdisciplinaire diachronique et dynamique des pratiques des populations actuelles et anciennes et des modes de pensée qui les sous-tendent. Les artéfacts découverts en fouilles sur le site de Huacosmarca sont confrontés aux chroniques et documents de l’époque coloniale et ceux-ci éclairent les données ethnographiques recueillies lors d’observations participantes des rituels actuels de la même zone géographique: le haut Chillón. Selon le rituel étudié, la porte d’entrée pour l’application du modèle peut varier mais l’analyse et la reconstruction s’effectuent toujours à travers les étapes bien identifiées du même processus. La démarche se veut résolument critique de la vision structuraliste et du postulat de la continuité des pratiques rituelles préhispaniques à travers les siècles. Elle est ancrée<p>dans la recherche et la mise en évidence des contingences historiques et géographiques locales, celles d'une zone des Andes Centrales.<p><p>The rituals related to the appeal for rain, to the cleaning of irrigation channels and to the cattle branding are analyzed and reconstituted with a pattern using the ethnographic, ethnohistorical and archaeological sources available. This pattern allows an interdisciplinary, diachronic and dynamic approach to the current and ancient population’s practices and to the patterns of thought that underlie them. The artefacts found in<p>excavations on the site of Huacosmarca are confronted with chronicles and documents of the colonial era and these throw light on ethnographic data collected from participant observation of those current rituals from the same geographic area: the high Chillon’s valley.<p>According to the ritual studied in this research, the gateway to the pattern’s application may vary but the analysis and reconstruction is always done through identified stages of<p>the same process. This approach criticizes the structuralist vision and the assumption of the continuity of prehispanic ritual practices through the centuries. It takes root in the research into the historical and geographical contingencies of the local area, those of the Central Andes. / Doctorat en Histoire, art et archéologie / info:eu-repo/semantics/nonPublished