Search

The paleomagnetic shipboard data of International Ocean Discovery Program Site U1475, with a record reaching back to approximately 7 Ma, allowed for the identification of major magnetic polarity chrons and subchrons back to ~3.5 Ma. However, the natural remanent magnetization (NRM) was very weak, and transitional intervals with unclear polarity were as thick as several meters. The midpoints of these transitional intervals were reported in the shipboard results without decimal places because of the poor data quality. To evaluate and possibly refine the shipboard magnetostratigraphy, subsampling was performed across the polarity transitions. Detailed alternating field (AF) demagnetization experiments were conducted on these discrete samples and were complemented by anhysteretic remanent magnetization acquisition measurements and subsequent demagnetization. AF demagnetization data of NRM were analyzed using anchored principal component analysis (PCA) to obtain the characteristic remanent magnetization. These PCA results generally confirm the smoothed signal across polarity transitions at Site U1475. However, the midpoint depths of the top of the Keana Subchron, the Gauss-Matuyama and Matuyama-Brunhes boundaries, and the base of the Olduvai Subchron were adjusted.

Small lakes and wetlands from high eleva- tion within the Sierra Nevada Range (southern Spain) preserve a complete post-glacial Holocene record. Isotopic, TOC and C/N analyses, carried out on a sediment core, show various stages in the evolution of the Borreguiles de la Virgen, which today constitute a small bog at about 2,950 m above sea level. Glacial erosion generated a cirque depression, which became a small lake during the first phase of infilling (from 8,200 to 5,100 cal yr BP), as suggested by sedimentary evidence, including an atomic C/N ratio generally below 20, low TOC values and the highest d 13 Ca ndd 15 N values of the record. These results imply significant algal productivity, which is confirmed by the microscopic algal remains. Drier conditions became established progressively in this area from 5,100 to 3,700 cal yr BP. Subsequently, the lake evolved into a bog as shown by geochemical evidence (C/N ratios above 20, high TOC content and low d 13 C values). Unstable conditions prevailed from 3,600 to 700 cal yr BP; an extremely low sedimentation rate and scarcity of data from this period do not allow us to make a coherent interpretation. Fluctuating conditions were recorded during the last *700 cal yr BP, with wetter conditions prevailing during the first part of the interval (with C/N rate below 20) up to 350 years ago. In general, a gradual trend toward more arid conditions occurred since *6,900 - cal yr BP, with a further increase in aridity sin- ce *5,100 cal yr BP. This evidence is consistent with other contemporaneous peri-Mediterranean records.

New data and a review of historiographic information from Neolithic sites of the Malaga and Algarve coasts (southern Iberian Peninsula) and from the Maghreb (North Africa) reveal the existence of a Neolithic settlement at least from 7.5 cal ka BP. The agricultural and pastoralist food producing economy of that population rapidly replaced the coastal economies of the Mesolithic populations. The timing of this population and economic turnover coincided withmajor changes in the continental and marine ecosystems, including upwelling intensity, sea-level changes and increased aridity in the Sahara and along the Iberian coast. These changes likely impacted the subsistence strategies of the Mesolithic populations along the Iberian seascapes and resulted in abandonments manifested as sedimentary hiatuses in some areas during the Mesolithic-Neolithic transition. The rapid expansion and area of dispersal of the early Neolithic traits suggest the use of marine technology. Different evidences for a Maghrebian origin for the first colonists have been summarized. The recognition of an early North-African Neolithic influence in Southern Iberia and the Maghreb is vital for understanding the appearance and development of the Neolithic in Western Europe. Our review suggests links between climate change, resource allocation, and population turnover., The results presented in this paper derive from research carried out under the sponsorship of the following projects: Fundação para a Ciência e a Tecnologia (Portugal) and the European Science Foundation (III Community Support Framework), PTDC/HAH/64548/2006, A.F.C. & J.F.G., funded by the European Union and the Fundação para a Ciência e Tecnología; HAR 2008-1920 (Ministerio de Ciencia e Innovación, Spain) and European Research Council2008-AdG 230561. Archeological sites management by M.C.S. & M.D.S.V. with permits from the Junta de Andalucía (Spain). This work also benefited from funding from the following projects: CGL2009-07603, CTM2009-07715, CSD2006-00041 and HAR2008-06477-C03-03/HIST, all from the Ministerio de Ciencia e Innovación, Spain; 200800050084447 (MARM), Project RNM 05212 and Research Group 0179 (Junta de Andalucía, Spain). E.S. received financial support of the FCT (grant: SFRH/BPD/26525/2006). F.J. Jiménez Espejo acknowledges the CSIC “JAE-Doc” postdoctoral program for funding.

8 pages, 4 figures, 1 table., The stratigraphy of the late Neanderthal occupation of Gorham's Cave, Gibraltar, between 33 and 24 ka BP, the latest known site of Neanderthal occupation, is discussed. Level IV at Gorham's Cave exclusively records Neanderthal occupation and is characterised by Mousterian technology and a sequence of 22 AMS dates. The overlying Level III is Upper Palaeolithic, and the earliest diagnostic culture is the Solutrean at around 18.5 ka BP. A dating interval of over four thousand years separates these two horizons. The ecological and bioclimatic characteristics of the site are considered as an explanation for the late survival of the Neanderthals in the region.

4 pages, 1 table, 1 figure., The late survival of archaic hominin populations and their long contemporaneity with modern humans is now clear for southeast Asia1. In Europe the extinction of the Neanderthals, firmly associated with Mousterian technology, has received much attention, and evidence of their survival after 35 kyr BP has recently been put in doubt2. Here we present data, based on a high-resolution record of human occupation from Gorham’s Cave, Gibraltar, that establish the survival of a population of Neanderthals to 28 kyr BP. These Neanderthals survived in the southernmost point of Europe, within a particular physiographic context, and are the last currently recorded anywhere. Our results show that the Neanderthals survived in isolated refuges well after the arrival of modern humans in Europe., We thank all those who have participated in this project. The project Palaeomed was co-funded by the Government of Gibraltar and the European Union Interreg IIIB Programme Medocc. Palynological and geochemical investigations were funded by Fundación Séneca, Murcia, Spain, and Ministerio de Educación y Ciencia, DGI, Spain, respectively. Geomorphological work was funded by Ministerio de Educación y Ciencia, DGI, Spain.