16 research outputs found
Approaches to land snail shell bead manufacture in the Early Holocene of Malawi
Shell disc beads are important archeological indicators of social communication and exchange networks. There has been substantial research on ostrich eggshell (OES) beads, but little is known about the manufacture or chronology of similar beads from land snail shells (LSS). LSS beads are associated with Holocene hunter-gatherers in Africa, though direct dates are limited to the Iron Age, and there are no images or descriptions of the manufacturing sequence. Here, we combine experimental and archeological data to resolve the chronology, operational chains, and material properties of LSS bead manufacture. We then recommend and apply a modified OES production sequence to three Later Stone Age assemblages from the Kasitu Valley of northern Malawi (Hora 1, Mazinga 1, and Kadawonda 1). At these sites, LSS shows an unexpectedly high proportion of Pathway 2 manufacture (disc shaping prior to perforation), in direct contrast with known OES bead manufacture. Application of red color occurred at all stages of manufacture, albeit inconsistently. Production of finished beads involved substantial removal of material from preforms to create the final product. Finally, we report the earliest evidence for LSS bead manufacture with two directly dated preforms (~ 9500 cal BP), showing that the origins of LSS beadmaking do precede the Iron Age.Introduction Background and previous research - The problem of land snail disc beads - Land snail shell versus ostrich eggshell Materials and methods - Experimental methods -- Breakage -- Shaping -- Drilling -- Pigments - Archeological samples -- Site descriptions -- Recovery protocols -- Sorting, data collection, and analysis -- Dating Results - Experimental results -- Breakage -- Shaping -- Drilling -- Production stages specific to LSS -- Application of pigments - Archeological results -- Assemblage description -- Manufacturing chains -- Dating Discussion Conclusion
Ancient DNA and deep population structure in sub-Saharan African foragers
Multiple lines of genetic and archaeological evidence suggest that there were major demographic changes in the terminal Late Pleistocene epoch and early Holocene epoch of sub-Saharan Africa(1-4). Inferences about this period are challenging to make because demographic shifts in the past 5,000 years have obscured the structures of more ancient populations(3,5). Here we present genome-wide ancient DNA data for six individuals from eastern and south-central Africa spanning the past approximately 18,000 years (doubling the time depth of sub-Saharan African ancient DNA), increase the data quality for 15 previously published ancient individuals and analyse these alongside data from 13 other published ancient individuals. The ancestry of the individuals in our study area can be modelled as a geographically structured mixture of three highly divergent source populations, probably reflecting Pleistocene interactions around 80-20 thousand years ago, including deeply diverged eastern and southern African lineages, plus a previously unappreciated ubiquitous distribution of ancestry that occurs in highest proportion today in central African rainforest hunter-gatherers. Once established, this structure remained highly stable, with limited long-range gene flow. These results provide a new line of genetic evidence in support of hypotheses that have emerged from archaeological analyses but remain contested, suggesting increasing regionalization at the end of the Pleistocene epoch.
DNA analysis of 6 individuals from eastern and south-central Africa spanning the past approximately 18,000 years, and of 28 previously published ancient individuals, provides genetic evidence supporting hypotheses of increasing regionalization at the end of the Pleistocene.info:eu-repo/semantics/publishedVersio
First Record Of Myosorex (Mammalia: Soricidae) From Malawi With Description As A New Species, Myosorex gnoskei
We describe a new species of Myosorex from Nyika National Park, northern Malawi. Myosorex gnoskei (the Nyika burrowing shrew) represents the first record of the genus from the country. Recently collected between pine plantations and adjacent to the headquarters of a major national park, this new species of shrew highlights the need for further comprehensive sampling of habitats, even those thought to be ‘well-known\' and adjacent to human disturbance. The specimen was taken at an elevation of 2285 m., suggesting a relict montane distribution. In cranial dimensions, this new species of shrew rivals Myosorex kihaulei, and ranks second only to Myosorex schalleri as the smallest described member of the genus. This new record also fills in a major gap in the distribution of the genus in the regions of the Albertine and Malawi Rifts. There are no published records in the region between 3o05\'S (just north of Lake Tanganyika) and 14o30\'S (south of Lake Malawi). This void includes the countries of Angola, Zambia, Malawi, Democratic Republic of Congo (SE), Tanzania (W), and Zimbabwe (N). Keywords: Myosorex., shrew, new species, Albertine Rift, Malawi RiftJournal of East African Natural History Vol. 97 (1) 2008: pp. 19-3
Economic impact of maize research in Tanzania
Maize was introduced in Tanzania in the 16th century but research on appropriate varieties and management practices did not get underway until the 1940s. In 1974, a National Maize Research Program (NA{RP) was established to co-ordinate maize research. During 1974-1994 the NM RP released 15 varieties. This study was conducted to assess the socio-economic impact of maize technology Development and transfer investment from 1974 to 1994. Standard pre-tested questionnaire and multi-stage sampling procedures were used for primary data collection. Data were collected from 978 farmers in 53 sites across seven agroecological zones. The sample survey revealed that the adoption rate of the improved varieties for the various zones were 28%, 66%, 44%, 24%, 66%, 81 % and 36% for the Central, Eastern, Lake, Northern, Southern, Southern Highlands and the Western Zones, respectively. The study demonstrated that farmers adopt the cheapest and low-risk technological components in a stepwise process reflecting the profitability and riskiness of each component. The estimated rate of return for the maize research and Development in Tanzania was 19%
Speciation mirrors geomorphology and palaeoclimatic history in African laminate-toothed rats (Muridae: Otomyini) of the Otomys denti and Otomys lacustris species-complexes in the 'Montane Circle' of East Africa
We adopted an integrated systematic approach to delimit evolutionary species and describe phylogeographic, morphometric and ecological relationships in Otomys denti (from the Albertine Rift, Southern Rift in Malawi and the northern Eastern Arc Mountains) and Otomys lacustris (from the Southern Rift in Tanzania and Zambia, and the southern Eastern Arc Mountains). Molecular [cytochrome (cyt) b sequences, 1143 bp, N = 18], craniometric (classical, N = 100 and geometric, N = 60) and ecological (Partial Least Squares regression of shape and ecogeographic variables) approaches show a profound, parallel disjunction between two groups: (1) Eastern Arc and Southern Rift (including the Malawi Rift) (O. lacustris and Otomys denti sungae) and (2) Albertine Rift (Otomys denti denti and Otomys denti kempi) taxa. Within both groups, cyt b sequences or craniometric analysis provided evidence for the differentiation of both southern and northern Eastern Arc from Southern Rift lineages (across the so-called Makambako Gap). Within the Albertine Rift (denti-kempi) lineage, populations from individual mountain ranges differed significantly in skull shape (but not size), but were similar genetically. Over-reliance in the past on very few morphological characters (e.g. number of molar laminae) and a polytypic species concept has obscured phylogenetic relationships and species discrimination in this group. We recognize at least three species in this group, and distinct lineages within two of these species. Each species or lineage was endemic to one of three regions: the Albertine Rift, the Malawi Rift or the Eastern Arc. Our result echo conclusions of recent studies of other mammalian and bird taxa and reflect the geomorphology and palaeoclimatic history of the region. © 2009 The Linnean Society of London.Articl
Hunter-gatherer environments at the Late Pleistocene sites of Mwanganda's Village and Bruce, northern Malawi
Mwanganda's Village (MGD) and Bruce (BRU) are two open-air site complexes in northern Malawi with deposits dating to between 15 and 58 thousand years ago (ka) and containing Middle Stone Age (MSA) lithic assemblages. The sites have been known since 1966 aOpen access articleThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]
Policy evaluation and efficiency: a systematic literature review
This paper provides a systematic literature review of studies investigating the effect of an intervention on the efficiency of a decision-making unit, when efficiency is computed using nonparametric frontier approaches. This paper offers a guide for future research by identifying patterns in (1) the fields of application, (2) applied efficiency models, and (3) analysis of efficiency determinants. Our findings indicate that, despite the prominent role of frontier techniques in the analysis of public sector performances and the importance of the effectiveness and the policy perspective, these two approaches have long been kept separate. Nevertheless, the combination of efficiency and effectiveness is fundamental to evaluate public interventions and to detect inefficiencies at the policy level, especially in key sectors such as education, health, and environment