Some palaeoecological data from Rondonia, southern part of the Amazon Basin. ()

Palynological investigations on sediment cores from three localities in Rondonia in the southern part of the Amazon Basin, indicate that marked vegetational changes have ocurred there. The series of samples from Katira represents the late Cenozoic, probably Quaternary. The sediments from Capoeira might be partly of Holocene age (and possibly Upper Pleistocene as well). Apparently the climatic changes during several intervals of the Late Cenozoic (Quaternary) caused the development of savannas in this region which is now covered in tropical forest.O conceito de que houve períodos de clima seco durante o Pleistoceno na Amazônia, vem sendo debatido por inúmeros pesquisadores nos últimos anos. A teoria dos refúgios, proposta por Haffer, deu início a uma série de estudos para a explicação das mudanças climáticas da área amazônica. A maioria desses estudos foram baseados na distribuição atual de certas espécies de plantas e animais. Entretanto, o uso de dados para interpretação das flutuações climáticas no Pleistoceno exige uma extrapolação. Evidências palinológicas de Rondônia mostraram que savanas de gramíneas substituíram a floresta tropical durante certos períodos do Pleistoceno. Neste trabalho são discutidos os resultados da análise de pólen de amostras de sedimentos de Rondônia. Os diagramas polínicos mostraram mudanças na vegetação de floresta para savana o vice-versa. Os sedimentos de Katira devem ser de idade Cenozóica Superior, provavelmente Quaternária. Os sedimentos de Capoeira representam em parte uma idade do Holoceno (e, possivelmente, do Pleistoceno Superior). As condições climáticas ocorridas durante certos intervalos do Cenozóico Superior (Quaternário) parecem ter favorecido ao desenvolvimento de savanas na área em discussão, que é atualmente coberta pela floresta tropical

Chironomid-based palaeotemperature estimates for northeast Finland during Oxygen Isotope Stage 3.

Quantitative palaeotemperature estimates for the earlier part of Oxygen Isotope Stage (OIS-) 3 are inferred from subfossil chironomid remains. The high-latitudinal study site of Sokli, northeast Finland, provides for a unique lacustrine deposit covering the earlier part of OIS-3, and the chironomid remains found in the sediments show that a shallow lake with a diverse fauna was present at the study site throughout the record. Using a Norwegian calibration data set as a modern analogue, mean July air temperatures are reconstructed. The chironomid-inferred July air temperatures are surprisingly high, reaching values similar to the current temperature at the study site. Other proxies that were applied to the sediments included the analysis of botanical and zoological macro-remains, and our results concur with temperature estimates derived from climate indicator taxa. Summer temperatures for interstadial conditions, reconstructed with climate models, are as high as our proxy-based palaeotemperatures

Upper pleistocene and holocene climate and vegetation of the “Sabana de Bogota” (Colombia, South America)

The uppermost 32 metres of a 2436 metre core principally of lake sediments, Pleistocene and Holocene in age from the Sabana de Bogotá were analysed for its pollen content, at intervals of 10—15 cm. About seventy species, genera of families could be recognized, many of them for the first time. The rest of the core is being analysed and the results will be published later. The Sabana de Bogotá lies at an altitude of approximately 2500 metres above sea level, 4½°—5° North of the equator, and 74°—74½° West of Greenwich. From the diagram it may be deduced that glacial and interglacial periods affected the tropics equally as Europe and North America. It also shows that the glacial periods were at the same time pluvials, and the interglacials interpluvials. Curves for the real fluctuations of the tree-line, changes of annual precipitation and changes of temperature have been calculated (fig. 5). Temperatures during the high-glacial phases of the Würm glacial were ± 8° C lower than today, the altitude of the tree-line was some 1300 metres less than now and the snow-line showed an even greater difference (fig. 5). Radiocarbon dates prove that the parts of the section considered to be respectively Holocene and later Würm-glacial really correspond to those ages. Moreover the temperature curve for the upper Pleistocene of the Sabana de Bogotá corresponds surprisingly well with that published by Emiliani for surface ocean water and by Gross for Europe (fig. 6). With this knowledge it seemed fully justified to correlate also the older phases with the glacials and interglacials of Europe and North America, using principally the alpine nomenclature. The lowest part of the diagram seems to correspond to the end of Hiss I (= Drenthe stadial), followed by the Riss I—II interstadial, and the Riss II (= Warthe stadial). Then follows the Riss-Würm interglacial, the Würm-glacial (subdivided by two long interstadials, together called Interpleniglacial), and the Holocene. The more important conclusions of the present study are summarized in paragraph 12

Estudio especializado N° 1. Pollenanalysis of the telarmachay rockshelter (PERU)

INTRODUCTION The Telarmachay rockshelter is situated on the edge of the high plain of Junin (Perú)’, at an altitude of 4 420 m, and at a distance of 20 km from the large Junin Lake (approx. 11°11’ lat. S 75°52’ long. E). The area is in the upper part of the « alpine zone », in the Puna grassland formation. The rockshelter was excavated by a team guided by D. Lavallée and M. Julien of the Centre de Recherches Archéologiques (C. N. R. S.), between 1975 and 1980. The samples were sent to us by D..

Telarmachay

El abrigo de Telarmachay está ubicado en los Andes centrales del Perú (departamento de Junín) a una altura de 4420 m s.n.m., en la puna. Los trabajos de excavación, de 1975 a 1980, estuvieron a cargo de un grupo de prehistoriadores franceses y estudiantes peruanos, bajo la dirección de Danièle Lavallée. Las excavaciones, realizadas con el método del decapado por niveles naturales (19 pasadas en total), sobre una superficie de 35 m2, evidenciaron 7 niveles de ocupación sucesivas, cada una de ellas caracterizada por un modo específico de acondicionamiento y utilización del abrigo. La ocupación empieza alrededor de 9000 BP y prosigue casi sin interrupción hasta 2000 BP aproximadamente. A partir de 34 fechados 14C se estableció la cronología siguiente: Fase VII, ca. 9000-7200 BP; Fase VI, ca. 7200-6800 BP; Fase V inf., 6800-5700 BP; Fase V sup., ca. 5700-5000 BP; Fase IV, ca. 5000/4500-3800 BP; Fase III, ca. 3800-2800 BP; Fase II, ca. 2800-2000 BP; (Fase 1, nivel superficial). Una excepcional riqueza en vestigios faunísticos permitió demostrar, por primera vez en los Andes, la existencia de un proceso de domesticación in situ de los camélidos andinos desde 6000-5500 BP aproximadamente: entre 9000 y 7200 BP se practica una caza generalizada de los ongulados (camélidos y cérvidos) que evoluciona , entre 7200 y 6000 BP, hacia una caza especializada de las vicuñas y de los guanacos; entre 6000 y 5500 BP aparecen los primeros animales domesticados, de tipo alpaca y, por fin, después de 5500 BP, el pastoreo de animales completamente domesticados (alpacas y, en proporción menor, llamas). Los análisis arqueozoológicos permitieron también determinar que la ocupación del abrigo fue estacional y tenía lugar entre diciembre y abril. Las otras categorías de vestigios (herramientas y desechos líticos, instrumentos de huesos) fueron analizados morfológica y morfométricamente, lo que permitió percibir su evolución cronológica. Por otra parte, se realizaron varios estudios funcionales (análisis de las microhuellas de uso, experimentaciones, analogías etnográficas). El cotejo de todas las informaciones obtenidas llevó a una percepción etnológica de la historia de la ocupación humana en Telarmachay. Las técnicas empleadas y las diversas tareas efectuadas (caza, recolección, pastoreo; trabajo de la piedra y del hueso; tratamiento de las pieles; usos domésticos y técnicas del fuego) fueron reconstituidas. Finalmente, el análisis espacial llevó a una reconstrucción del espacio habitado y a la definición de áreas de actividades especializadas, para cada fase de ocupación. Al mismo tiempo, se reveló una permanencia relativa de las modalidades generales de acondicionamiento del abrigo a lo largo del periodo precerámico