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- A stalagmite test of North Atlantic SST and Iberian hydroclimate linkages over the last two glacial cyclesPublication . Denniston, Rhawn F.; Houts, Amanda N.; Asmerom, Yemane; Wanamaker Jr., Alan D.; Haws, Jonathan; Polyak, Victor J.; Thatcher, Diana L.; Altan-Ochir, Setsen; Borowske, Alyssa C.; Breitenbach, Sebastian F. M.; Ummenhofer, Caroline C.; Regala, Frederico T.; Benedetti, Michael M.; Bicho, Nuno Gonçalo Viana Pereira FerreiraClose coupling of Iberian hydroclimate and North Atlantic sea surface temperature (SST) during recent glacial periods has been identified through the analysis of marine sediment and pollen grains co-deposited on the Portuguese continental margin. While offering precisely correlatable records, these time series have lacked a directly dated, site-specific record of continental Iberian climate spanning multiple glacial cycles as a point of comparison. Here we present a high-resolution, multi-proxy (growth dynamics and delta C-13, delta O-18, and delta U-234 values) composite stalagmite record of hydroclimate from two caves in western Portugal across the majority of the last two glacial cycles (similar to 220 ka). At orbital and millennial scales, stalagmite-based proxies for hydroclimate proxies covaried with SST, with elevated delta C-13, delta O-18, and delta U-234 values and/or growth hiatuses indicating re-duced effective moisture coincident with periods of lowered SST during major ice-rafted debris events, in agreement with changes in palynological reconstructions of continental climate. While in many cases the Portuguese stalagmite record can be scaled to SST, in some intervals the magnitudes of stalagmite isotopic shifts, and possibly hydroclimate, appear to have been somewhat decoupled from SST.
- Middle and late stone age of the Niassa region, Northern Mozambique. Preliminary resultsPublication . Bicho, Nuno Gonçalo Viana Pereira Ferreira; Haws, Jonathan; Raja, Mussa; Madime, Omar; Gonçalves, Célia; Cascalheira, João; Benedetti, Michael M.; Pereira, Telmo; Aldeias, VeraLocated between modern-day South Africa and Tanzania, both of which have well-known and extensive Stone Age records, Mozambique's Stone Age sequence remains largely unknown in the broader context of African Pleistocene prehistory. Such lack of data occurs despite the key geographical location of the country, in southern Africa at the southeastern tip of the Great Rift Valley. As such, Mozambique is an area of interest to evaluate the origins and dispersion of Homo sapiens within Africa, particularly in relation to Middle Stone Age contexts and associated early modern human ecology and cognition.This paper focuses on preliminary survey results from the Niassa District, near Lake Niassa (also known as Lake Malawi) in northern Mozambique. The results include the discovery and location of more than 80 new surface lithic concentration localities, as well as data from two new sites, the open air surface site of Ncuala and the rock shelter of Chicaza. For Chicaza we provide a series of new radiocarbon dates for the Iron Age and Late Stone Age occupations based on preliminary testing carried out at the site. (C) 2015 Elsevier Ltd and INQUA. All rights reserved.
- Portable art and personal ornaments from Txina-Txina: a new later stone age site in the Limpopo River Valley, southern MozambiquePublication . Bicho, Nuno Gonçalo Viana Pereira Ferreira; Cascalheira, João; André, Lino; Haws, Jonathan; Gomes, Ana; Gonçalves, Célia; Raja, Mussa; Benedetti, Michael M.This paper reports on preliminary fieldwork at the Later Stone Age site of Txina-Txina in Mozambique. Excavation yielded a long stratigraphic sequence, a large lithic assemblage, a unique decorated gastropod shell fragment and two ostrich eggshell beadsthe first of their type recovered from a Stone Age context in Mozambique.