Pronounced zonal heterogeneity in Eocene southern high-latitude sea surface temperatures

Paleoclimate studies suggest that increased global warmth during the Eocene epoch was greatly amplified at high latitudes, a state that climate models cannot fully reproduce. However, proxy estimates of Eocene near-Antarctic sea surface temperatures (SSTs) have produced widely divergent results at similar latitudes, with SSTs above 20 degrees C in the southwest Pacific contrasting with SSTs between 5 and 15 degrees C in the South Atlantic. Validation of this zonal temperature difference has been impeded by uncertainties inherent to the individual paleotemperature proxies applied at these sites. Here, we present multiproxy data from Seymour Island, near the Antarctic Peninsula, that provides well-constrained evidence for annual SSTs of 10-17 degrees C (1 sigma SD) during the middle and late Eocene. Comparison of the same paleotemperature proxy at Seymour Island and at the East Tasman Plateau indicate the presence of a large and consistent middle-to-late Eocene SST gradient of similar to 7 degrees C between these two sites located at similar paleolatitudes. Intermediate-complexity climate model simulations suggest that enhanced oceanic heat transport in the South Pacific, driven by deep-water formation in the Ross Sea, was largely responsible for the observed SST gradient. These results indicate that very warm SSTs, in excess of 18 degrees C, did not extend uniformly across the Eocene southern high latitudes, and suggest that thermohaline circulation may partially control the distribution of high-latitude ocean temperatures in greenhouse climates. The pronounced zonal SST heterogeneity evident in the Eocene cautions against inferring past meridional temperature gradients using spatially limited data within given latitudinal bands

Diretrizes curriculares do curso de pedagogia no Brasil: disputas de projetos no campo da formação do profissional da educação Curriculum guidelines of the pedagogy course in Brazil: project disputes in the field of the training of education professionals

Neste artigo, os autores analisam as novas diretrizes curriculares do curso de pedagogia, objeto de normatização do Conselho Nacional de Educação (CNE), em 2005, a partir do debate feito à luz do acervo de conhecimentos teórico-práticos sistematizados pelas principais entidades do campo educacional (ANFOPE, ANPED, CEDES, FORUMDIR, ANPAE).<A NAME="tx01"></A><A HREF="#nt01">1</A> Evidenciam, criticamente, alguns dos problemas e das tensões que marcam a trajetória desse curso ao longo da história da educação brasileira. Focalizam, no âmbito das políticas educacionais, em especial, o movimento dos educadores pela definição das diretrizes curriculares para a formação dos profissionais da Educação Básica, que reflete posições de ordem epistemológica, pedagógica e política atinentes às visões e aos projetos educacionais em disputa, no Brasil, nas últimas décadas. A problematização das diretrizes curriculares concorre para ampliar a compreensão da complexidade do campo da pedagogia e dos desafios teórico-práticos com que as instituições de ensino superior, em particular as universidades, deparam-se para materializar a reforma do curso de pedagogia, na esteira das novas regulamentações legais e na perspectiva de uma formação cidadã.<br>Based on the debate conducted in the light of the theoretical-practical knowledge acquired by the main organisms of the educational field (ANFOPE, ANPED, CEDES, FORUMDIR, ANPAE), the authors analyze the new curriculum guidelines of the pedagogy course, which was regulated by the Conselho Nacional de Educação (CNE - Brazilian Council for Education) in 2005. They critically highlight some of the problems and tensions that have marked the trajectory of this course along the history of Brazilian education. Within the educational policies, they more particularly focus on the educator movement for the definition of curriculum guidelines for the training of basic education professionals, which reflects some epistemological, pedagogical and political positions related to the educational visions and project in dispute, in Brazil, these last decades. Problematizing the curriculum guidelines helps understanding better how complex the field of pedagogy is and what theoretical-practical challenges face the higher education institutions, more particularly universities, in order to concretize the reform of the pedagogy course to comply with the new legal regulations but also from the point of view of a citizen training

Phanerozoic trends in the global diversity of marine invertebrates

It has previously been thought that there was a steep Cretaceous and Cenozoic radiation of marine invertebrates. This pattern can be replicated with a new data set of fossil occurrences representing 3.5 million specimens, but only when older analytical protocols are used. Moreover, analyses that employ sampling standardization and more robust counting methods show a modest rise in diversity with no clear trend after the mid-Cretaceous. Globally, locally, and at both high and low latitudes, diversity was less than twice as high in the Neogene as in the mid-Paleozoic. The ratio of global to local richness has changed little, and a latitudinal diversity gradient was present in the early Paleozoic

At the root of the early penguin neck: a study of the only two cervicodorsal spines recovered from the Eocene of Antarctica

The spinal column of early Antarctic penguins is poorly known, mainly due to the scarcity of articulated vertebrae in the fossil record. One of the most interesting segments of this part of the skeleton is the transitional series located at the root of the neck. Here, two such cervicodorsal series, comprising reinterpreted known material and a new specimen from the Eocene of Seymour Island (Antarctic Peninsula), were investigated and contrasted with those of modern penguins and some fossil bones. The new specimen is smaller than the counterpart elements in recent king penguins, whereas the second series belonged to a large-bodied penguin from the genus Palaeeudyptes. It had been assigned by earlier researchers to P. gunnari (a species of “giant” penguins) and a Bayesian analysis—a Bayes factor approach based on size of an associated tarsometatarsus—strongly supported such an assignment. Morphological and functional studies revealed that mobility within the aforementioned segment probably did not differ substantially between extant and studied fossil penguins. There were, however, intriguing morphological differences between the smaller fossil specimen and the comparative material related to the condition of the lateral excavation in the first cervicodorsal vertebra and the extremely small size of the intervertebral foramen located just prior to the first “true” thoracic vertebra. The former feature could have resulted from discrepancy in severity of external pneumatization. Both fossils provided valuable insights into the morphology and functioning of the axial skeleton in early penguins