Search results for "East africa"
showing 10 items of 37 documents
After the emergence of the Acheulean at Melka Kunture (Upper Awash, Ethiopia): From Gombore IB (1.6 Ma) to Gombore Iγ (1.4 Ma), Gombore Iδ (1.3 Ma) a…
2021
International audience; While the emergence of the Acheulean is well documented in East Africa at ~1.7 Ma, subsequent developments are less well understood and to some extent controversial. Here, we provide robust evidence regarding the time period between 1.6 Ma and 1.2 Ma, based on an interdisciplinary approach to the stratigraphic sequences exposed in the Gombore gully of Melka Kunture, in the upper Awash Valley of Ethiopia. Throughout the Pleistocene, the environment differed significantly from elsewhere in Africa because of the elevation at 2000 m asl, the cooler and rainy climate, the Afromontane vegetation, the development of endemic animal species, and the recurrent impact of volcan…
The aspect of nationality and performance in a mountain ultra-marathon-the ‘Swiss Alpine Marathon’
2012
Eichenberger E, Knechtle B, Rust CA, Lepers R, Rosemann T, Onywera VO. The aspect of nationality and performance in a mountain ultra-marathon - the ‘Swiss Alpine Marathon’ J. Hum. Sport Exerc. Vol. 7, No. 4, pp. 748-762, 2012. Runners from East Africa and especially from Kenya dominate middle- and longdistance running races worldwide. The aim of the present study was to investigate the participation and performance trends regarding the nationality of runners in a mountain ultra-marathon held in partially high alpine terrain. We hypothesized that Kenyan runners, living and training in the Great Rift Valley, a predominantly hilly, mountainous and altitudinous region like the Alps, would domin…
Performance of Kenyan athletes in mountain versus flat marathon running - An example in Switzerland
2013
Harm, C., Knechtle, B., Rust, A.C., Rosemann, T., Lepers, R. & Onywera, V. (2013). Performance of Kenyan athletes in mountain versus flat marathon running - An example in Switzerland. J. Hum. Sport Exerc., 8(4), pp.881-893. The purpose of this study was to compare running performance of Kenyans in a flat city marathon and a mountain marathon in Switzerland. Running times of top three overall Kenyan runners were compared with running times of top three overall runners of other nations in a mountain and a flat marathon held in Switzerland between 2003 and 2011. In the mountain marathon top three male Kenyans achieved with 199±23min the 11th fastest running time behind athletes from Italy (177…
Participation and performance trends of East-African runners in Swiss half-marathons and marathons held between 2000 and 2010.
2013
Abstract Background This study examined the changes in participation, performance and age of East African runners competing in half-marathons and marathons held in Switzerland between 2000 and 2010. Methods Race times, sex, age and origin of East African versus Non-African finishers of half-marathon and marathon finishers were analyzed. Results Across time, the number of Kenyan and Ethiopian finishers remained stable (P > 0.05) while the number of Non-African finishers increased for both women and men in both half-marathons and marathons (P < 0.05). In half-marathons, the top ten African women (71 ± 1.4 min) and top three (62.3 ± 0.6 min) and top ten (62.8 ± 0.4 min) African men were …
Does the potentially toxic cyanobacterium Microcystis exist in the soda lakes of East Africa?
2011
Presently, the food chains of the famous saline alkaline flamingo-lakes of East Africa are the focus of intense scientific discussion as the lakes host toxic cyanobacteria, which when consumed by Lesser Flamingos, weaken the birds and therefore make them susceptible to attacks by infective diseases. The distribution, genetic and toxicological aspects of Microcystis in Kenya has been studied extensively. Although there are reports on the occurrence of Microcystis in Kenya’s hypersaline alkaline lakes, they have not been confirmed. Our investigations carried out over a 10-year period in about 50 inland waters showed that Microcystis occurs exclusively in freshwaters, but never in the hypersal…
Spatial coherence and potential predictability assessment of intraseasonal statistics of wet and dry spells over Equatorial Eastern Africa
2012
The aim of this study was to derive components of the intraseasonal rainfall variations from the daily rainfall in the Equatorial Eastern Africa region and assess their spatial coherence, a pointer to their potential predictability. Daily rainfall observations from 36 stations distributed over Equatorial Eastern Africa and extending from 1962 to 2000 were used. The March to May and October to December periods commonly referred to as the long and short rainfall seasons respectively were considered. Seasonal and intraseasonal statistics at the local (station) level were first defined. The stations were also grouped into near-homogeneous (sub-regional) zones based on daily rainfall. Similarly,…
Monthly survival of African Sylvia warblers in a seasonally arid tropical environment
2006
Latitudinal gradients of life-history traits in animals are thought to be shaped by environmental variables. For example, it has been suggested that the increase in avian clutch size from the tropics towards the northern temperate regions is caused by a reduced survival of adult birds in the north due to increasing environmental seasonality. However, the tropical savannahs of East Africa show pronounced seasonality in resources caused by distinct rainy and dry seasons. This raises the question of whether survival and other life-history traits of birds living in these tropical savannahs are influenced by this seasonality, making them more similar to northern temperate species. We used 2-year…
Chemical composition of modern and fossil hippopotamid teeth and implications for paleoenvironmental reconstructions and enamel formation – Part 2: A…
2012
Abstract. For reconstructing environmental change in terrestrial realms the geochemistry of fossil bioapatite in bones and teeth is among the most promising applications. This study demonstrates that alkaline earth elements in enamel of Hippopotamids, in particular Ba and Sr are tracers for water provenance and hydrochemistry. The studied specimens are molar teeth from Hippopotamids found in modern and fossil lacustrine settings of the Western Branch of the East African Rift system (Lake Kikorongo, Lake Albert, and Lake Malawi) and from modern fluvial environments of the Nile River. Concentrations in enamel vary by ca. two orders of magnitude for Ba (120–9336 μg g−1) as well as for Sr (9–21…
Prefazione a Sulaiman Addonia, Il silenzio è la mia lingua madre
2022
Sulaiman Addonia's 2018 novel Silence is My Mother Tongue, uncharacteristically set in a refugee camp, follows the sentimental education of a girl, Saba, in the place that she, her brother, and their friends have learnt to call home. The Preface to the Italian edition remarks how this classic and yet extraordinary coming-of-age novel offers a fundamental counter-narrative to the mainstream representations of life stories of minor refugees all over the world.
Potential predictability of crop impacting climate variables for East Africa and application to sorghum in the Mt Kenya area
2013
In Southern countries with rural low income populations, the vulnerability of rainfed agriculture to rainfall variability requires effective solutions to mitigate the effects of climatic hazards on crops. Predicting the characteristics of rainy seasons some time before they start should help the establishment of agricultural adaptation strategies to rainfall hazards. This is the objective of the present study, focused on East Africa (Kenya and northern Tanzania), and divided in three parts:- Define and document intra-seasonal descriptors (ISD) that will be considered in the predictability study. A new methodological approach has been developed in order to define the onset date (ORS) and the…