Intensive Farming, Agro-Diversity, and Food Security Under Conditions of Extreme Population Pressure in Western Kenya

This paper examines the impact of very high population densities and agricultural intensification on farm diversity and food security. Geertz and other researchers have suggested that intensification is likely to lead to crop specialization and a loss of diversity. Others, especially for Africa, have argued that intensification maintains or even increases agro-diversity. The case of Hamisi, in western Kenya, one of the most densely populated areas in all of rural Africa, supports the latter scenario. Farmers engage in a wide variety of sophisticated practices that maintain exceptionally high levels of agro-diversity. Their farming system includes complex patterns of intercropping, polyvariety, an emphasis on multi-purpose crops, and the close integration of crops and livestock. Despite this agro-diversity, we find that the intense population pressure in Hamisi has resulted in such small landholdings that diet quality and food security are seriously jeopardized. Despite the diversity of their farms, most families are highly dependent on market purchases and they consume very limited quantities of nutritionally dense foods, especially protein.     

The chronology of the cercopithecoidea of East Africa

The East African fossil record of cercopithecoids spans nearly 20 m. y. Throughout the Miocene Epoch, the diversity of monkeys was low, although at some localities the numbers of individuals is rather high. During the Plio-Pleistocene in contrast, there was a major radiation, or radiations of monkeys, involving both colobines and corcopithecines. A late Pleistocene to Recent radiation within the genusCercopithecus still seems to be under way. The history of diversity in the monkeys is in many ways a chronological inverted mirror image of the diversity history of the hominoid primates, which were highly diverse during the lower miocene, but became less diverse through time. The east african cercopithecoid record is the only one which spans much of the Neogene, and it is consequently the main one by which detailed cercopithecoid cladogenetic and anagenetic events can be dated. In this respect, it provides constraints for interpreting branching schemes derived from neontological evidence. Most of the neontological estimates for monkey origins appear to be too old, the fossil evidence suggesting that the origin of the superfamily Cercopithecoidea and the origins of the Colobinae, Papionini and Cercopithecini are younger than usually suggested on neontological evidence. The superfamily is probably no older than 25 m. y., the colobines diverged as a distinctive group about 12–14 m. y. ago, the Papionines about 8–10 m. y. ago and the Cercopithecines perhaps as late as 7 m. y. However, since the Miocene fossil record is rather spotty, these fossil-based estimates may be revised downwards with new discoveries. They are unlikely to be revised upwards. The sequence and timing of cladogenetic events deduced from the east african evidence indicates that all the modern subfamilies arose in Africa, and subsequently spread to Europe and Asia. The sequence of fossil events is in close agreement with neontological evidence such as karyology and molecular anthropology. It is only in the calibration of the sequence that there is disagreement between the fossil and neontological evidence. Strangely, the polarity of the differences in opinion are opposite to those concerning the hominoids, in which the neontological evidence has suggested much younger divergence dates than did the fossil evidence as perceived in the 1960's and 1970's.     

Foliicolous lichens: ecological and chorological data*

SERUSIAUX, E., 1989. Foliicolous lichens: ecological and chorological data . Foliicolous lichens are present throughout tropical and subtropical forests but are particularly common in undisturbed rain forests at low elevations. Their presence in south-west Europe and in the Caucasus with 23 species is considered to be a relic of Tertiary times. Ecological groups (in the sense of P. Duvigneaud) are determined, especially for the European taxa. Factorial analysis has been performed on a large collection from Central East Africa which enables the relationships between the foliicolous floras of the different types of forests present in the area (equatorial, mountane, riverine, etc.) to be determined.     

Why Starch as our Main Food Supply?

Starch is the main supply of polyglucosans for our metabolism because, in contrast to cellulose, it is easily digested and can be stored without serious difficulty in seeds or tubers and as flour. Glycogen which is easily metabolized by reversible synthesis and mobilization in animal tissues is too expensive for mass production.     

Paleogeographic variations of pedogenic carbonate delta13C values from Koobi Fora, Kenya: implications for floral compositions of Plio-Pleistocene hominin environments

Plio-Pleistocene East African grassland expansion and faunal macroevolution, including that of our own lineage, are attributed to global climate change. To further understand environmental factors of early hominin evolution, we reconstruct the paleogeographic distribution of vegetation (C(3)-C(4) pathways) by stable carbon isotope (delta(13)C) analysis of pedogenic carbonates from the Plio-Pleistocene Koobi Fora region, northeast Lake Turkana Basin, Kenya. We analyzed 202 nodules (530 measurements) from ten paleontological/archaeological collecting areas spanning environments over a 50-km(2) area. We compared results across subregions in evolving fluviolacustrine depositional environments in the Koobi Fora Formation from 2.0-1.5 Ma, a stratigraphic interval that temporally brackets grassland ascendancy in East Africa. Significant differences in delta(13)C values between subregions are explained by paleogeographic controls on floral composition and distribution. Our results indicate grassland expansion between 2.0 and 1.75 Ma, coincident with major shifts in basin-wide sedimentation and hydrology. Hypotheses may be correct in linking Plio-Pleistocene hominin evolution to environmental changes from global climate; however, based on our results, we interpret complexity from proximate forces that mitigated basin evolution. An approximately 2.5 Ma tectonic event in southern Ethiopia and northern Kenya exerted strong effects on paleography in the Turkana Basin from 2.0-1.5 Ma, contributing to the shift from a closed, lacustrine basin to one dominated by open, fluvial conditions. We propose basin transformation decreased residence time for Omo River water and expanded subaerial floodplain landscapes, ultimately leading to reduced proportions of wooded floras and the establishment of habitats suitable for grassland communities.     

The life and death of a street boy in East Africa: everyday violence in the time of AIDS

This article focuses on the life history of a single street boy in northwestern Tanzania, whom I name Juma. I suggest that Juma's experiences and the life trajectory of himself and of significant individuals around him (particularly his mother) were structured by everyday violence. I describe everyday violence in terms of a conjuncture between macrostructural forces in East Africa (including a history of failed development schemes and the contemporary political economy of neoliberalism) and the lived experience of individuals as they negotiate local, contextual factors (including land-tenure practices, the power dynamics between immediate and extended kin, life on the streets, and constructions of gender and sexuality). I suggest that AIDS and its many impacts on Juma's life course can only be understood in a broader context of everyday violence. From this basis, I draw several general conclusions regarding AIDS prevention and intervention strategies.     

DNA Fingerprinting of Trypanosoma vivax Isolates Rapidly Identifies Intraspecific Relationships

ABSTRACT. Using the polymerase chain reaction and arbitrarily selected oligonucleotide primers of 10 or 11 bases, we have amplified DNA sequences from Trypanosoma vivax parasites isolated from South America and Africa. On the basis of polymorphisms in the DNA fingerprints generated by three of the primers, the parasites could be separated into two major groups, one comprising T. vivax isolates from Kenya and the second including all the other T. vivax parasites (from Colombia, The Gambia, Nigeria and Uganda). One of these three primers (ILo 525) also gave isolate-specific DNA fingerprints for the parasites for the parasites tested, which will allow the use of this technique both in the species identification and discrimination of T. vivax parasites.     

A man-eating lion (Panthera leo) from Tanzania with a toothache

Between August 2002 and April 2004, a man-eating lion killed 35 people and injured at least 9 in a 350-km² area 150 km south-west of Dar es Salaam in Tanzania. Man-eating by lions is common in Southern Tanzania, but this case was exceptional due to the high number of victims attributed to a single animal. After having been killed by game scouts and villagers, it was found to be a young adult male. Dental examination revealed a broken upper left molar where a serious abscess and caries had developed. The lion must have been in permanent pain, and this probably explains its preference for man-eating. Most man-eating lions in Tanzania are healthy animals without signs of infirmity.     

Pastoral Sedentarization and Its Effects on Children’s Diet,Health, and Growth Among Rendille of Northern Kenya

Throughout the arid regions of Africa formerly mobile pastoral populations are becoming sedentary. Although pastoral sedentarization is encouraged by international development agencies and national governments as solutions to food insecurity, poor health care, and problems of governance, it has not been demonstrated that abandoning the pastoral way of life, and particularly childrens access to milk and other livestock products, is beneficial to the health and well-being of pastoral populations. This paper reports the results of a 3-year study of one pastoral and four settled Rendille communities of northern Kenya based on data from 17 repeated bimonthly surveys of childhood dietary, growth, and morbidity patterns and household level economic strata. Bivariate analysis of 5,535 measurements from 488 children from birth to 9 years revealed that age-specific height and weight measurements for the pastoral community are uniformly heavier and taller than children from the sedentary villages. Multivariate analysis using Generalized Estimating Equations methodology showed that the amount of milk consumed was always a statistically significant determinant of child weight and height growth, regardless of drought or non-drought times and breastfeeding status. Other significant determinants of child growth include morbidity and poverty, both associated with sedentary communities. These results indicate that international development assistance should not neglect improvements in livestock production and support of pastoral movements in Africas arid lands.     

Studies on Trypanosoma vivax: comparison of parasitological diagnostic methods.

Leeflang P., Buys Janny and Blotkamp Coby. 1978. Studies on Trypanosoma vivax: comparison of parasitological diagnostic methods. International Journal for Parasitology8: 15–18. Parasitological methods for the diagnosis of Trypanosoma vivax infections in Nigerian cattle, including thin and thick blood smear and lymph gland smear examination, haematocrit centrifuge technique, hypotonie lysis test and mouse inoculation were evaluated. In 155 blood samples, thick film examination was significantly better than thin smear examination; in 126 samples, the haematocrit centrifuge technique was significantly superior over thin smear but not over thick film examination; when all six methods were applied in 52 samples, significant differences could only be demonstrated between mouse inoculation on one hand and thick film and gland smear examination, haematocrit centrifuge technique and hypotonie lysis test on the other hand, and between thin smear examination and hypotonic lysis test. It was shown that none of the tests was either satisfactory or sufficiently reliable to be used alone. The combination of either haematocrit centrifuge technique or thick film examination together with thin smear examination is recommended as most practical for the diagnosis of T. vivax infection under field conditions. The haematocrit centrifuge technique is also more advantageous because simultaneous estimation of the packed cell volume will evaluate the clinical condition of the herd. A comparison of the value of diagnostic methods for East and West African T. vivax was included in the present study.     

Turkana pastoralism: A case against the Tragedy of the Commons

This paper examines land-use practice among the Turkana pastoralists of Kenya. Drawing on work of both ecologists and anthropologists, it examines the argument that posits that pastoralism is inherently destructive to the environment, commonly referred to as the Tragedy of the Commons. Results of this research suggest that the livestock management practices of East African pastoralists do not degrade the environment, that livestock numbers do not exceed the carrying capacity of the land, and that social institutions successfully function to cope with environmental problems.