Etudie les prix et les structures du marché pétrolier, la conjoncture et les politiques pétrolières, le pétrole et développement économique. « Copyright Electre »

Monograph of conference papers on the emerging role of the petroleum industry in international relations and economic relations - examines multinational enterprise and government policies, the influence of foreign policies, pricing mechanisms, OPEC experience, etc. References and statistical tables. Conference held in quebec 1975 October 2 to 4.

Les techniques qui autrefois étaient représentatives de la structure et de la diversité des civilisations, sont devenues aujourd’hui les sous-systèmes de la technologie mondiale. L’ouvrier et ses instruments risquent fort de faire les frais de ce procès d’uniformisation et d’y perdre leur identité ou, si l’on préfère, leur caractère irremplaçable. Notre époque sera-t-elle celle de « la fin des outils » ? En bien des points du globe, elle a marqué la fin de l’état de différence ; signifiera-t-elle aussi la suppression pure et simple du droit à la différence ? S’agit-il d’une évolution inéluctable, est-ce la rançon de ce que l’on appelle fort mal à propos le progrès ? Autour de ces questions essentielles, traitées selon l’optique personnelle de chaque auteur, des thèmes complémentaires ont surgi : la critique des méthodes conventionnelles d’analyse, l’importance de l’approche historique, l’étude des incidences (économiques, sociales, politiques, culturelles, écologiques, etc.) du transfert (ou du non-transfert effectif !) de technologie...

Identifying the influence of history on the diversity of life is an important goal of evolutionary biology, whether it is an historical event that is extrinsic to the organism such as past climate change or an intrinsic event such as a single switch in behavior. Phylogenetic trees offer an indirect record of the history of diversification in a group of organisms and can be used in conjunction with other information to deduce the multiple roles of history affecting a particular group. Intra- and inter-specific phylogenetic relationships in the spider genus Agelenopsis Geibel (Araneae: Agelenidae) were analyzed using sequence data from two mitochondrial genes, cytochrome oxidase I (COI) and 16S ribosomal RNA for 12 out of 13 described species as well as a potential new species. These data were used to address a number of questions regarding biogeography, speciation, and evolution of habitat-use. Concerning biogeography, patterns and levels of sequence variation were consistent with the hypothesis that Pleistocene climate change affected geographic distribution and evolutionary diversification patterns within A. aperta. Speciation patterns were uncovered regarding species monophyly, geography of speciation, and the rejection of a putative hybrid species. Finally, a potential interaction of history and natural selection was identified when looking at the evolution of habitat use within and among Agelenopsis species. It was found that riparian living arose once in the genus with a single switch to arid living. Subsequently, three species of Agelenopsis displayedmultiple switches back to riparian living. The findings of this dissertation point to a multitude of evolutionary questions that should be addressed and suitability of Agelenopsis as a model system in evolutionary biology.