Environments and trypanosomiasis risks for early herders in the later Holocene of the Lake Victoria basin, Kenya

Specialized pastoralism developed ∼3 kya among Pastoral Neolithic Elmenteitan herders in eastern Africa. During this time, a mosaic of hunters and herders using diverse economic strategies flourished in southern Kenya. It has been argued that the risk for trypanosomiasis (sleeping sickness), carried by tsetse flies in bushy environments, had a significant influence on pastoral diversification and migration out of eastern Africa toward southern Africa ∼2 kya. Elmenteitan levels at Gogo Falls (ca. 1.9–1.6 kya) preserve a unique faunal record, including wild mammalian herbivores, domestic cattle and caprines, fish, and birds. It has been suggested that a bushy/woodland habitat that harbored tsetse fly constrained production of domestic herds and resulted in subsistence diversification. Stable isotope analysis of herbivore tooth enamel (n = 86) from this site reveals, instead, extensive C4 grazing by both domesticates and the majority of wild herbivores. Integrated with other ecological proxies (pollen and leaf wax biomarkers), these data imply an abundance of C4 grasses in the Lake Victoria basin at this time, and thus little risk for tsetse-related barriers to specialized pastoralism. These data provide empirical evidence for the existence of a grassy corridor through which small groups of herders could have passed to reach southern Africa.

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The Contribution of Stable Isotope Analysis to the Study of Childhood Movement and Migration

10.1093/oxfordhb/9780199670697.013.27 ◽

2018 ◽

Cited By ~ 1

Author(s):

Katie A. Hemer ◽

Jane A. Evans

Keyword(s):

Stable Isotope ◽

Stable Isotope Analysis ◽

Tooth Enamel ◽

Isotope Analysis ◽

Early Years ◽

Human Tooth ◽

Population Mobility ◽

Single Tooth ◽

Non Local ◽

And Migration

Stable isotope analysis is firmly established as a method for the investigation of past population mobility. The distinction between local and non-local individuals within a cemetery population relies on identifying an individual’s place of childhood residence through the analysis of strontium and oxygen isotopes present in human tooth enamel. Traditionally, studies investigating mobility focus on the analysis of a single tooth. More recently, however, it has become apparent that in order to investigate the mobility of an individual during childhood—and thus to consider the importance of children in the migration process—it is necessary to analyse a series of teeth which form at different stages during the early years of life. This chapter will consider the potential of—and challenges surrounding—this scientific approach to the investigation of childhood mobility in the past.

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The Development of a Customization Framework for the WRF Model over the Lake Victoria Basin, Eastern Africa on Seasonal Timescales

Advances in Meteorology ◽

10.1155/2015/653473 ◽

2015 ◽

Vol 2015 ◽

pp. 1-15 ◽

Cited By ~ 12

Author(s):

R. Argent ◽

X. Sun ◽

F. Semazzi ◽

L. Xie ◽

B. Liu

Keyword(s):

Lake Victoria ◽

Wrf Model ◽

Initial Step ◽

Research Unit ◽

Eastern Africa ◽

Climatic Research Unit ◽

Climate Projections ◽

Lake Basin ◽

Lake Breeze ◽

Lake Victoria Basin

Lake Victoria, Africa, supports millions of people. To produce reliable climate projections, it is desirable to successfully model the rainfall over the lake accurately. An initial step is taken here with customization of the Weather, Research, and Forecast (WRF) model. Of particular interest is an asymmetrical rainfall pattern across the lake basin, due to a diurnal land-lake breeze. The main aim is to present a customization framework for use over the lake. This framework is developed by conducting several series of model runs to investigate aspects of the customization. The runs are analyzed using Tropical Rainfall Measuring Mission rainfall data and Climatic Research Unit temperature data. The study shows that the choice of parameters and lake surface temperature initialization can significantly alter the results. Also, the optimal physics combinations for the climatology may not necessarily be suitable for all circumstances, such as extreme years. The study concludes that WRF is unable to reproduce the pattern across the lake. The temperature of the lake is too cold and this prevents the diurnal land-lake breeze reversal. Overall, this study highlights the importance of customizing a model to the region of research and presents a framework through which this may be achieved.

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Use of Stable Isotope Analysis to Reveal Relationships between Diet and Tooth Ablation Types in Jomon Period Japan

A World View of Bioculturally Modified Teeth ◽

10.5744/florida/9780813054834.003.0010 ◽

2017 ◽

Author(s):

Soichiro Kusaka

Keyword(s):

Stable Isotope ◽

Stable Isotope Analysis ◽

Tooth Enamel ◽

Isotope Analysis ◽

Bone Collagen ◽

Stable Isotope Ratios ◽

Hunter Gatherers ◽

And Migration ◽

Important Evidence ◽

Lower Incisors

This chapter discusses the practice of ritual tooth ablation in Japan in relation to diet and migration. Ablation was practiced extensively among hunter-gatherers, and the tradition typically followed one of two patterns, type 4I and type 2C, depending on whether the lower incisors or canines were extracted, respectively. To test the hypothesis that a dependence on marine resources for food differed depending on ablation type during childhood and adulthood, stable isotope ratios of bone collagen and tooth enamel were measured. It was discovered that diets did vary among individuals with different ablation types in the Inariyama population. The findings provide important evidence that biocultural dietary differences were related to ablation type in the Jomon period.

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Uncertainty in calibrating generalised Pareto distribution to rainfall extremes in Lake Victoria basin

Hydrology Research ◽

10.2166/nh.2014.052 ◽

2014 ◽

Vol 46 (3) ◽

pp. 356-376 ◽

Cited By ~ 15

Author(s):

Charles Onyutha ◽

Patrick Willems

Keyword(s):

Parameter Estimation ◽

Pareto Distribution ◽

Lake Victoria ◽

Estimation Method ◽

Eastern Africa ◽

Rainfall Time Series ◽

Lake Victoria Basin ◽

Parameter Estimation Method ◽

Rainfall Extremes ◽

Generalised Pareto Distribution

Uncertainty in the calibration of the generalised Pareto distribution (GPD) to rainfall extremes is assessed based on observed and large number of global climate model rainfall time series for nine locations in the Lake Victoria basin (LVB) in Eastern Africa. The class of the GPD suitable for capturing the tail behaviour of the distribution and extreme quantiles is investigated. The best parameter estimation method is selected following comparison of the method of moments, maximum likelihood, L-moments, and weighted linear regression in quantile plots (WLR) to quantify uncertainty in the extreme intensity quantiles by employing the Jackknife method and nonparametric percentile bootstrapping in a combined way. The normal tailed GPD was found suitable. Although the performance of each parameter estimation method was acceptable in a number of evaluation criteria, generally the WLR technique appears to be more robust than others. The difference between upper and lower limits of the 95% confidence intervals expressed as a percentage of the empirical 10-year rainfall intensity quantile ranges from 9.25 up to 59.66%. The assessed uncertainty will be useful in support of risk based planning, design and operation of water engineering and water management applications related to floods in the LVB.

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Mammoth tooth enamel growth rates inferred from stable isotope analysis and histology

Quaternary Research ◽

10.1016/j.yqres.2012.02.002 ◽

2012 ◽

Vol 77 (3) ◽

pp. 424-432 ◽

Cited By ~ 26

Author(s):

Jessica Z. Metcalfe ◽

Fred J. Longstaffe

Keyword(s):

Growth Rate ◽

Growth Rates ◽

Tooth Enamel ◽

Isotope Analysis ◽

Extension Rate ◽

Quaternary Deposits ◽

Isotopic Studies ◽

Migration Strategies ◽

And Migration ◽

Isotopic Measurements

Mammoth (Mammuthus sp.) teeth are relatively abundant in Quaternary deposits from Eurasia and North America, and their isotopic compositions can be used to reconstruct past seasonal patterns in precipitation, diet, and migration. Strategies for collecting and interpreting such data, however, are strongly dependent on growth rates, which can vary among species, individuals, and within teeth. In this study, we use histological and isotopic measurements to determine enamel growth rates for a Columbian mammoth (Mammuthus columbi) tooth in two directions. Using histology, the growth rate through the enamel thickness (ET; perpendicular to the height of the tooth) is estimated at 0.8 to 1.5 mm/yr. Isotopic sampling through the innermost 0.36 mm of the ET recovered less than half a period of variation (i.e., half an inferred year of growth), which is consistent with the histological estimate for ET growth rate. A combination of histological and isotopic measurements suggests that the enamel extension rate (growth in the height of the tooth) is 13–14 mm/yr. Knowledge of enamel growth rates should improve the design and interpretation of future isotopic studies of mammoth teeth. The combination of histological and isotopic measurements may also prove useful in determining growth rates for other extinct taxa.

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Phylogeography and genealogy of the tsetse fly Glossina pallidipes (Diptera: Glossinidae)

International Journal of Tropical Insect Science ◽

10.1017/s1742758415000223 ◽

2016 ◽

Vol 36 (01) ◽

pp. 32-47 ◽

Cited By ~ 3

Author(s):

E.S. Krafsur ◽

J.G. Marquez ◽

J.O. Ouma

Keyword(s):

Southern Africa ◽

Dna Sequences ◽

Glossina Pallidipes ◽

Tsetse Fly ◽

Late Nineteenth Century ◽

Tsetse Flies ◽

Frequency Distributions ◽

African Populations ◽

Contraction And Expansion ◽

Population Suppression

Glossina pallidipes, a widely but discontinuously distributed African savanna species, is one of the economically important tsetse flies because it is a vector of trypanosomiasis, a lethal disease of cattle and other domestic animals. DNA sequences of ribosomal (r16S2, 249 bp) and cytochrome oxidase I (COI, 421 bp) concatenated mitochondrial genes were analysed in 23 geographically diverse samples ofG. pallidipesfrom Ethiopia, Kenya, Tanzania, Zambia and Zimbabwe. Among 873 flies, we detected 181 composite haplotypes and found that their spatial diversities and frequency distributions were heterogeneous. Haplotype and nucleotide diversities were greatest in Ethiopia and least in southern Africa. We observed little haplotype and nucleotide diversity among regions, and detected severely limited maternal gene flow among the sampled populations (ΦST= 0.42). Tests for demographic stability and analysis of mismatch distributions revealed regionally contrasting demographic histories. The Ethiopian populations were phylogenetically the oldest and genetically the most diverse, and exhibited successive waves of contraction and expansion. The southern African populations were phylogenetically the youngest and genetically the least diverse, and showed only a single, recent expansion. Likely ecological correlates of historical tsetse fly demography include population suppression trials in East Africa and recurring rinderpest epizootics in southern Africa, beginning in the late nineteenth century that reduced host mammalian populations.

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The Role of the Dominant Modes of Precipitation Variability over Eastern Africa in Modulating the Hydrology of Lake Victoria

Advances in Meteorology ◽

10.1155/2014/516762 ◽

2014 ◽

Vol 2014 ◽

pp. 1-11 ◽

Cited By ~ 11

Author(s):

Kara A. Smith ◽

Fredrick H. M. Semazzi

Keyword(s):

East Africa ◽

Southern Oscillation ◽

Lake Victoria ◽

Rainfall Variability ◽

Precipitation Variability ◽

Eastern Africa ◽

Annual Rainfall ◽

Lake Victoria Basin ◽

The Relationship

Previous water budget studies over Lake Victoria basin have shown that there is near balance between rainfall and evaporation and that the variability of Lake Victoria levels is determined virtually entirely by changes in rainfall since evaporation is nearly constant. The variability of rainfall over East Africa is dominated by El Niño-Southern Oscillation (ENSO); however, the second and third most dominant rainfall climate modes also account for significant variability across the region. The relationship between ENSO and other significant modes of precipitation variability with Lake Victoria levels is nonlinear. This relationship should be studied to determine which modes need to be accurately modeled in order to accurately model Lake Victoria levels, which are important to the hydroelectric industry in East Africa. The objective of this analysis is to estimate the relative contributions of the dominant modes of annual precipitation variability to the modulation of Lake Victoria levels for the present day (1950–2012). The first mode of annual rainfall variability accounts for most of the variability in Lake Victoria levels, while the effects of the second and third modes are negligible even though these modes are also significant over the region.

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