Great Rift Research Articles

A Rare Case of Chronic Schistosomiasis Occurring within a Tubular Adenoma Eight Years Following Infection

Purpose: Schistosomes infect about 200 million people annually. Schistosoma mansoni is endemic to South America, Africa, and the middle east. Found in fresh water, the parasite makes use of snails as an infective reservoir. Schistosomiasis may persist if untreated. Chronic schistosomiasis may cause hepatic complications, including periportal fibrosis and portal hypertension. We present the only reported case in the U.S. of incidental colonic schistosomiasis within a tubular adenoma eight years following infection. A 56-year-old man presented for colonoscopy for polyp surveillance. He was in good health and free of any gastrointestinal or constitutional complaints. Colonoscopic exam revealed diverticulosis and two small sessile polyps, one in the cecum and one in the rectum. Both polyps were tubular adenomas with epitheloid granulomata. Within the cecal polyp, a schistosome egg was noted. The appearance was consistent with Schistosoma mansoni. On subsequent questioning, the patient reported wading in Lake Eyasi in the Great Rift Valley of Tanzania during an excursion that occurred eight years prior. Pathology slides from his index colonoscopy were reviewed, and showed epithelioid granuloma. He was treated with a one-day course of praziquantel, and his travel companions were referred for serologic testing for schistosomiasis. We present a case of chronic schistosomiasis. Each year, approximately 200 million people are infected with schistosome species worldwide. Free-swimming cercariae leave the snail and penetrate mammalian skin. The parasites migrate to the portal venous system, where they mature. Early symptoms, if present, include a rash at the site of skin penetration. A less common syndrome of fever, myalgia, hepatomegaly, and eosinophilia is also well established. The patient's travel history established a time of infection approximately eight years ago. The endoscopic findings of mucosal congestion and polyps were far from specific. Therefore, the histologic findings of epitheliod granuloma, eosinophilic infiltration of the laminal propria, and schistosoma ova were key to the diagnosis. Both hyperplastic and adenomatous polyps have been associated with schistosomes. A relationship between Schistosoma japonicum and cancer of the large intestinal have been proposed. However, Schistosoma mansoni does not appear to be related to the development of colonic neoplasm. This case represents an unusual finding of chronic schistosomiasis in a patient living in the United States.

Stable isotope analyses of tooth enamel carbonate of large herbivores from the Tugen Hills deposits: Palaeoenvironmental context of the earliest Kenyan hominids

Understanding shifts in past climatic and environmental conditions are crucial for throwing light on human evolution. Available reconstructions of the palaeoecology of faunal and floral assemblages indicate that the earliest Kenyan hominids, including Orrorin tugenensis, are associated with forest landscapes. In this study, we present stable isotope data of tooth enamel carbonate of large herbivores associated with these hominids in order further to evaluate their environmental context. Fossil teeth were sampled in the Lukeino Formation (6.1–5.7 Ma, Late Miocene) and the Mabaget Formation (5.3–4.5 Ma, Early Pliocene) at the foot of the Tugen Hills (Great Rift Valley). Despite chemical changes in fossil enamel, preservation of the palaeoenvironmental signals is supported by the difference in δ18O between hippos and terrestrial fauna. Moreover, the giraffid specimen from the Mabaget Formation exhibits one of the highest δ18O values, as expected for a drought-tolerant animal. The δ13C of large herbivores indicates that the earliest Kenyan hominids inhabited a mixed C3–C4 environment as did Ardipithecus (Ethiopia) and Sahelanthropus (Chad), two early putative hominids. The Tugen Hills might have been a wooded grassland with patches of woodland. There is no record of closed-canopy forest at the time of deposition. We emphasize differences in food habits among herbivore groups. Deinotheres, nearly all elephantids and the giraffid individual had a C3 diet which reflected browsing behaviour. The intake of C4 plants prevailed for equids and gomphotheres and was consistent with grazing habits. Most hippos and suids were mixed C3–C4 feeders and consequently were generalist herbivores. Bovids and rhinos had a diet ranging from C3 to C4 plants. Variations in δ13C and δ18O among faunal assemblages suggest changes in local climate and vegetation. Moister conditions likely occurred in the Early Pliocene and the latest Miocene (ca. 5.7 Ma) than before. The C3 plant biomass would have increased in the latest Miocene. There were probably denser stands of trees within the depositional environment during the Early Pliocene than in the Late Miocene, which is consistent with palaeontological studies.

Application of wavelet empirical orthogonal function analysis to investigate the nonstationary character of Ethiopian rainfall and its teleconnection to nonstationary global sea surface temperature variations for 1900–1998

ABSTRACTThis study employed the wavelet empirical orthogonal function (WEOF) analysis to analyse the nonstationary variability of rainfall in Ethiopia and global sea surface temperature (SST) for 1900–1998. The study found that the nonstationary variations of both the June to September (JJAS) and February to May (FMAM) Ethiopian rainfall can be delineated into three zones: western half of Ethiopia north of the Great Rift Valley (GRV), southern Ethiopia south of the GRV and the GRV from southwestern Ethiopia to the Afar Triangle. The leading wavelet principal component (WPC) signals showed that Ethiopian rainfall had been in stagnation for most of 1900–1998, with major droughts in the 1940s and 1980s. The dominant frequencies of Ethiopian rainfall ranged between 2 and 8 years. In western Ethiopia, the 2–4‐year rainfall frequencies dominated the rainfall variation, but their trends are modulated by 5–7‐year frequencies, whereas in the Afar Triangle, the 5–7‐year frequencies were dominant. Between 1900 and 1998, the Afar Triangle region experienced decreasing rainfall for 60 years (1900–1960). The seasonal global SST revealed that regardless of what time of the year, the strongest contributions to global SST variations occur in the Antarctic Ocean, the El Niño region of South America and in the southwestern Pacific Ocean, followed by the Atlantic and the Indian Oceans. Further, this study also shows annual migrations of SST variations in the El Niño region, the Antarctic and the Atlantic Oceans. The leading SST signal variations show that SST warming started in the Atlantic and Indian Oceans, from 1950 to 1975, and spread to the Antarctic Ocean between 1960 and 1990, which probably contributed to the melting of sea ice. Teleconnections between WPC1 of Ethiopian rainfall and SST scale‐averaged wavelet power were found for the El Niño region and northern Atlantic, west of the Sahara desert.

Methods for early evaluation for resistance to bacterial blight of coffee

Bacterial Blight of Coffee (BBC) caused by Pseudomonas syringae pv garcae has become of major concern in Kenya due to its increasing incidence and severity. For decades, the disease was confined within and to the west of the Great Rift Valley, but recently it has spread to reach other coffee growing areas. In order to minimize the chemical input in its management, which apart from polluting the environment have high cost implications, development of resistant/tolerant cultivars is highly recommended. This study aimed at developing an effective method(s) for early evaluation of resistance to BBC and to use the method(s) to evaluate the reaction of selected coffee genotypes to different isolates of P. syringae pv garcae. Three isolates from different coffee growing areas in Kenya were used to inoculate thirteen coffee genotypes using injection and cut methods. The two inoculation methods were found to be effective and can be recommended with slight modifications. However, it was not possible to clearly authenticate the reaction of the different genotypes to BBC since the genotypes responded differently to different isolates and inoculation methods. Key words: Coffee, Pseudomonas syringae pv garcae, inoculation method, Kenya.

The rise of potentially toxin producing cyanobacteria in Lake Naivasha, Great African Rift Valley, Kenya

Lake Naivasha, an important inland water ecosystem and a crucial freshwater resource in the Great African Rift Valley, has displayed clear signals of degradation in recent decades. We studied the phytoplankton composition and biomass levels in the period 2001–2013 and noted a progressive increase in the occurrence of potentially toxic cyanobacteria. Analyses for the presence of cyanotoxins such as microcystins (MC), cylindrospermopsin (CYN) and anatoxin-a (ATX-a) were carried out on samples collected in 2008–2013. Among the cyanotoxins tested, low concentrations of MC were detected in the lake. This is the first record of the occurrence of MC in Lake Naivasha. For the first time, molecular phylogenetic investigations of field clones of cyanobacteria from Lake Naivasha were carried out to establish the taxa of the dominant species. Amplification of the aminotrasferase (AMT) domain responsible for cyanotoxin production confirmed the presence of the mcyE gene belonging to the microcystin synthesis gene cluster in field samples containing Microcystis and Planktothrix species. These findings suggest that toxin producing cyanobacteria could become a threat to users of this over-exploited tropical lake in the near future.

Mapping Muslim Sacred Tombs in Palestine During the Mandate Period

The Muslim tombs of local saints and prophets were an integral part of the landscape of British Mandate Palestine. They were ubiquitous and significant; located in almost all parts of the region, from the slopes of the Hermon Mountain in the north, to the Negev Desert in the south. These shrines were found in cities, towns and countryside, extending from the shores of the Mediterranean to the Great Rift Valley. However, no systematic study of their extent or significant analysis of the monuments has been undertaken. Using British period maps and additional sources from the 1930–40s, this study analyses almost 800 Muslim tombs and sanctuaries. Through comparison with the Palestine Exploration Fund survey of the 1870s and other sources from the Late Ottoman Period, the article identifies patterns associated with these tombs, including their history and, in some cases, their origins and the changes that they underwent during this period. Case studies of different regions and analysis of the physical and geographical location of the monuments also sheds light on their significance in various regions of Palestine and to different population groups.

Application of Geochemical Methods in Geothermal Exploration in Kenya

The major goals of geochemical exploration are to obtain the subsurface composition of the fluids in a geothermal system and to use this to obtain information on temperature, origin, and flow direction, which help in locating the subsurface reservoir. Subsurface waters have been classified into meteoric water, ocean water, evolved connate water, magmatic water, and juvenile water. Geothermal water is mostly meteoric and oceanic water, although andesitic waters near subduction areas often contain significant proportions of evolved connate and magmatic waters. Geothermal waters have been classified with respect to their anion and cation contents into alkali-chloride water, acid sulphate water, acid sulphate-chloride water, and bicarbonate water. Acid waters are generally unsuitable for elucidation of subsurface properties. Conservative constituents are used for tracing the origin and flow of geothermal fluids, stable isotopes (especially 2H and 18O), along with B and Cl being most important. Rock forming constituents SiO2, Na, K, Ca, Mg, CO2, and H2) are used to predict subsurface temperatures and potential production problems such as deposition and corrosion. Kenya is located on the Great Rift Valley in Eastern Africa and has a huge potential for geothermal production of power and other direct uses. In this paper, we report on the geochemical methods used in Kenya to explore, develop, and monitor the available geothermal resources for power production and other direct uses.

Transferability and application of microsatellites (SSRs) from <i>Juniperus communis</i> L. to <i>Juniperus procera</i> Hochst. Ex endl.

Transferability of five nuclear microsatellite markers (Jc-16, Jc-31, Jc-32, Jc-35 and Jc-37) that were originally developed for J. communis was tested to J. procera. Jc-31 & Jc-37 showed successful amplifications and polymorphism in J. procera. Jc-35 which had been reported as polymorphic in J. communis was monomorphic in J. procera while the primer pair for Jc-32 failed to record any amplification. The remaining one primer pair (Jc-16) showed double loci ampli-fication in both J. procera and the control J. communis suggesting further examination of the primer pair and its binding sites. Genetic variation of six Ethiopian J. procera populations: Chilimo, Goba, Menagesha-Suba, Wef-Washa, Yabelo and Ziquala was assessed based on the two polymorphic loci (Jc-31 & Jc-37) in 20 - 24 individuals of each population. From these two loci, a total of 41 alleles could be retrieved. Two populations that are located south east of the Great Rift Valley together harboured 75% of private alleles signifying their deviant geo-ecological zones and suggesting special consideration for conservation. Chilimo, which is at the western margin of Juniper habitat in Ethiopian central highlands scored the highest fixation (FIS = 0.584) entailing lower immigrant genes and hence higher inbreeding. The AMOVA revealed that 97% of the variation resided within the population while still among population variation was significant (p

COMMENTARY

COMMENTARY

Altitudinal variation and conservation priorities of vegetation along the Great Rift Valley escarpment, northern Ethiopia

Understanding plant species distribution patterns along environmental gradients is fundamental to managing ecosystems, particularly when habitats are fragmented due to intensive human land-use pressure. To assist management of the remaining vegetation of the Eastern Afromontane Biodiversity Hotspot, plant species richness and diversity patterns were analyzed along the main elevation gradient (1,000–2,760 m) of the Great Rift Valley escarpment in northern Ethiopia, using 29 plots established at 100-m elevation intervals. A total of 129 vascular plant species belonging to 59 families was recorded. Species richness and diversity showed a hump-shaped relationship with elevation, peaking at mid-elevation (1,900–2,200 m). Beta diversity values indicated medium species turnover along the elevation gradient and were lowest at mid-elevation. Elevation strongly partitioned the plant communities (r = 0.98; P < 0.001). Four plant communities were identified along the elevation gradient: Juniperus procera–Clutia lanceolata community (2,400–2,760 m), Abutilon longicuspe–Calpurnia aurea community (1,900–2,300 m), Dracaena ombet–Acacia etbaica community (1,400–1,800 m), and Acacia mellifera–Dobera glabra community (1,000–1,300 m). To optimize conservation of species and plant communities, it is recommended that a conservation corridor be established along the elevation gradient that includes all four plant communities. This strategy—in contrast to creating single isolated reserves in zones with high species richness—is necessary for the habitat protection of species with narrow elevational ranges, in particular the globally endangered Nubian dragon tree (Dracaena ombet).

Does the decline of gastropods in deep water herald ecosystem change in Lakes Malawi and Tanganyika?

Summary1. Ancient, deep lakes have traditionally been considered as stable, ecological islands, well buffered from environmental change because of their great depth. However, they are not immune to anthropogenic and climatic stress. Ecosystems of the permanently stratified warm Lakes Malawi and Tanganyika in the Great East African Rift are particularly delicate. Their stratification regime has historically limited the distribution of benthic biota to a ‘bathtub ring of biodiversity’, namely substrata in the upper, oxygenated water layer.2. We use historical data on the endemic deep‐water molluscs of these lakes to assess present‐day stress on their benthic ecosystems. During the 20th century, these molluscs have probably decreased in abundance and migrated to shallower water.3. These apparent trends have a significance beyond species‐based conservation, foremost because deep‐water organisms heavily rely on the position and temporal stability of the oxycline and therefore provide an early warning of large‐scale changes in the distribution of dissolved oxygen. Oxygen demands have increased in the East African Great Lakes over the last century whereas ventilation of deep water has remained the same or declined.4. The combination of these factors is resulting in a narrowing of the ring of biodiversity and a changed nutrient flux through this ring. Reduction in the habitat available inevitably puts biota at risk, whereas changes in nutrient flux may cause shifts in the entire ecosystem or the collapse of parts of it.5. Considering the socioeconomic value of these lakes and the potentially grave implications for their faunal biodiversity and entire ecosystems, existing evidence of faunal decline, especially in taxa that depend strongly on the stratification regime, is of great concern. Moreover, because the factors responsible are widespread and include surface‐water warming, increased run‐off and eutrophication, respiration stress may also develop in other tropical and subtropical lakes.

A new species of the palaearctic genus Dasypoda Latreille 1802 (Hymenoptera: Dasypodaidae) from the Great Rift Valley in Ethiopia

Dasypoda is a genus of solitary bees previously recorded as endemic in the Palaearctic region from Portugal to Japan. Wedescribe here a new species of Dasypoda (Hymenoptera, Apoidea, Melittidae), Dasypoda riftensis sp. nov., collected fromEthiopia, Great Rift Valley, Gallo. This species is the first record of the genus Dasypoda in Sub-Saharan Africa and is of phylogenetic importance. We discuss biogeographical implications of the record in Ethiopia.

Basin-Scale Control on the Phytoplankton Biomass in Lake Victoria, Africa

The relative bio-optical variability within Lake Victoria was analyzed through the spatio-temporal decomposition of a 1997–2004 dataset of remotely-sensed reflectance ratios in the visible spectral range. Results show a regular seasonal pattern with a phase shift (around 2 months) between the south and north parts of the lake. Interannual trends suggested a teleconnection between the lake dynamics and El-Niño phenomena. Both seasonal and interannual patterns were associated to conditions of light limitation for phytoplankton growth and basin-scale hydrodynamics on phytoplankton access to light. Phytoplankton blooms developed during the periods of lake surface warming and water column stability. The temporal shift apparent in the bio-optical seasonal cycles was related to the differential cooling of the lake surface by southeastern monsoon winds. North-south differences in the exposure to trade winds are supported by the orography of the Eastern Great Rift Valley. The result is that surface layer warming begins in the northern part of the lake while the formation of cool and dense water continues in the southern part. The resulting buoyancy field is sufficient to induce a lake-wide convective circulation and the tilting of the isotherms along the north-south axis. Once surface warming spreads over the whole lake, the phytoplankton bloom dynamics are subjected to the internal seiche derived from the relaxation of thermocline tilting. In 1997–98, El-Niño phenomenon weakened the monsoon wind flow which led to an increase in water column stability and a higher phytoplankton optical signal throughout the lake. This suggests that phytoplankton response to expected climate scenarios will be opposite to that proposed for nutrient-limited great lakes. The present analysis of remotely-sensed bio-optical properties in combination with environmental data provides a novel basin-scale framework for research and management strategies in Lake Victoria.

The aspect of nationality and performance in a mountain ultra-marathon - the ‘Swiss Alpine Marathon’

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 dominate also a mountain ultra-marathon because they are accustomed to high altitudes and mountainous terrains. We examined the participation and performance trends of ultra-marathoners regarding their nationalities in the 78-km ‘Swiss Alpine Marathon’ including 21 km in high alpine terrain where 12,194 men and 1,781 women finished between 1998 and 2011. A total of 1,682 women and 11,580 men, corresponding to 94.9 % of all finishers, originated from Switzerland, Germany, Denmark, Italy, Sweden, Great Britain, Austria, the Netherlands and Luxembourg where only one male Kenyan runner ever participated. Female runners from Denmark, Great Britain, Germany, Luxembourg, Switzerland and Sweden as well as male runners from Denmark, Great Britain, and Sweden increased their participation significantly. Women from the Netherlands became slower whereas women originating from Great Britain became faster. Men from the Netherlands, Denmark, Germany and Switzerland became slower. The fastest runners originated from Switzerland for both women and men. To summarize, runners from Switzerland dominated the ‘Swiss Alpine Marathon’. Paradoxically, and interestingly, the Kenyan runners were not dominating the ‘Swiss Alpine Marathon’. Further studies should investigate Kenyan participation and performance in ultra-marathons in Africa such as the ‘Comrades Marathon’. Key words: ALPINE ULTRA-RUNNING, ULTRA ENDURANCE, ENDURANCE RUNNING, ETHNICITY.

Specific limits and emerging diversity patterns in East African populations of laminate-toothed rats, genus Otomys (Muridae: Murinae: Otomyini): Revision of the Otomys typus complex

We combined evidence from biogeography, craniodental traits, linear and geometric morphometrics (233 skulls), cytogenetics (karyotypes of 18 individuals) and mitochondrial DNA sequences (44 cytochrome b and 21 12S rRNA sequences) to test species limits within Otomys typus s.l. (Muridae: Murinae: Otomyini), a complex that is patchily distributed across alpine zones of Ethiopia and East Africa. Our results confirm the specific validity of O. dartmouthi, O. jacksoni, O. orestes, and O. uzungwensis, forms recently removed from synonymy under typus s.l.; support elevation of four other alpine forms to species (O. fortior, O. helleri, O. thomasi, and O. zinki); identify three additional new species (O. cheesmani sp. nov., O. simiensis sp. nov., O. yaldeni sp. nov.); and enable redefinition of O. typus s.s. as a species restricted to certain mountains west of the Great Rift Valley in Ethiopia (Simien and Guna Mountains in the north, extending to the highlands of the western rim of the Rift Valley). Phylogenetic interpretation of the cytochrome b data clearly demonstrates that the alpine morphotype once united under O. typus s.l. has originated independently at high elevations on several mountain ranges in eastern and northeastern Africa; although generally adapted to high-elevation vegetation, such alpine species are ecologically segregated from one another. Patterns of morphometric, genetic, and ecological differentiation among populations once misassigned to nominal O. tropicalis and O. typus more parsimoniously reflect regional cladogenesis along elevational gradients, rather than multiple, successive colonization by different ancestral forms from southern Africa as earlier supposed. Although incomplete and preliminary, information gathered for O. tropicalis indicates that it too is a species composite; several lines of research are discussed to redress its polyphyletic content. Our results, together with other recent taxonomic studies of Otomys, appreciably elevate the level of endemism within eastern Africa and underscore the significance of Africa's eastern highlands to the continental diversification of Otomyini.

Dispatches

Dispatches

Isolation and Initial Study of ØM3-16, a Bacteriophage Infecting an Alkaliphilic Vibrio metschnikovii Isolate from Lake Magadi, a Soda Lake in Kenya's Great Rift Valley

Extended abstract of a paper presented at Microscopy and Microanalysis 2011 in Nashville, Tennessee, USA, August 7–August 11, 2011.

Influence of fish cage farming on water quality and plankton in fish ponds: A case study in the Rift Valley and North Shoa reservoirs, Ethiopia

The potential impact of Nile Tilapia ( Oreochromis niloticus) cage culture on water quality and pelagic community composition was investigated in two Ethiopian small water bodies, one located in the highlands (Yemlo) and the other in the Great Rift Valley (Allage). This study was designed to assess the difference between the cages and open water in relation to those water quality changes attributable to intensive inputs of fish waste and left-over fish feed. All physico-chemical water quality parameters including inorganic nutrients varied temporally, coupled with dry and wet periods. The reservoir's trophic state ranged from eutrophic to hypereutrophic, with a strong correlation between chlorophyll- a and total phosphorus. The phytoplankton community was dominated by Cyanobacteria (84% of total phytoplankton abundance), in particular by Anabaenopsis sp. in Allage reservoir, whereas Chlorophyta (70%), with Pediastrum simplex as the dominant taxon, prevailed in Yemlo reservoir. A total of 23 zooplankton taxa were recorded during our sampling; rotifers were the richest group with 14 taxa distributed in 6 genera, followed by cladocerans represented by 6 taxa (5 genera) and copepods by 3 taxa (1 genus). Dissolved inorganic nutrient concentrations and other physical parameters showed no significant differences between the cages and open water. The exceptions were dissolved oxygen and ammonium nitrogen, which were lower and higher in the cages, respectively. For the whole study period of 240 days, the mean net weight and daily growth rate per fish were 183.3 g and 1.1 g d − 1 , respectively.

Atlas of the potential vegetation of Ethiopia

Floras and vegetation maps are the basis of understanding the ecology and botany of every country. Engler published the first map of the vegetation of Africa in 1882, defining the separation of African vegetation into firstly the forest regions, and secondly grasslands and wooded grasslands, a basic distinction that not surprisingly has remained intact. He refined his concepts over the years, putting the work into an evolutionary and phytogeographical context with his field research, particularly in East Africa, publishing a particularly important paper in Annals of Botany (Engler, 1904). Over the last century, floras for both African regions and individual countries have been published, with the Flora of Ethiopia and Eritrea, published over the period 1980 to 2009 by Swedish Science Press, including an up-to-date and thoroughly revised treatment of the diverse species that occur in these tropical but topographically diverse countries. With the increasing linkage of taxonomy with biogeography and ecology, it has now become common that vegetation maps are produced along with floras. This new comprehensive and well-researched volume by Friis et al. fills the need for a high-quality (1 : 2 000 000 or 5 cm : 100 km, with 90 × 90 m resolution) vegetation map of Ethiopia for land-use planning, natural resource management, agricultural development and conservation. Sadly, an important group of uses will also be to track the destruction of vegetation, areas where the ‘potential’ vegetation of the title is no longer present, and the effects of change in climate, and for this the Atlas sets an essential reference point. As with any field project, geographical information systems (GIS) and digital mapping have revolutionized the production of works such as this, particularly in large countries such as Ethiopia where the vegetation zones may be relatively small and with complex boundaries. In this case, much of the country is covered by the Ethiopian highlands, which lie mostly between 1300 and 2000 m, rising to over 4500 m. At lower elevations, the country includes the northern end of the Great Rift Valley, part of one of the major ecosystems of Africa. The first section of the book gives a 13-page review of details of the geography, geology and climate of the country, and this is followed by accounts of the methods used, the history of the vegetation and its study. These do provide an outstanding introduction to the country and I would recommend reading them to anyone visiting Ethiopia with interests in the natural environment. In the second section of the book there are formalized and detailed, but admirably concise and readable, descriptions of the 12 major vegetation types that are recognized, along with their sub-types. The authors nicely balance the distinction of indicator species between constancy and fidelity, with an appendix detailing occurrence of woody species in each recognized vegetation type. Conservation and erosion issues are discussed within the vegetation sections, although from my own interests I would have liked to see a little more about the crops that are characteristic of each zone and perhaps the invasive species. The final section of the book includes the maps themselves. These, with a scale of 1 : 2 000 000, are appropriately detailed with respect to the vegetation types. I am sure it will be no difficulty for the specialist who will mostly make use of the Atlas, but as a recent casual visitor to the country, I would have found it useful to have had coordinates along the axes to avoid juggling of road maps too! The volume is very nicely produced, with well over 100 colour illustrations, mostly filling a half-page, which give an immediate impression of the nature and structure of each of the vegetation types. Apart from the vegetation maps, it also has about 20 maps of various environmental and geographical features, and reproductions of earlier vegetation maps. A minor criticism of many maps is that the shades of colours are very hard to correlate with the legends, and quite impossible to follow in a dark hotel room. Maybe consideration should be given to combining the shades with a numeric key, as is done in the British Geological Survey maps. While most book reviews require some consideration of the readership, I expect this book has a well-defined audience: any organization involved in land-use, development, agriculture, tourism as well as plant taxonomy should have a copy available. It is a very high-quality study of the vegetation of Ethiopia, filling a significant gap. As such the volume should find a place in all libraries that cover the geography and land use of the continent, as well as herbaria with East African collections. I certainly found it an invaluable reference while driving and flying around parts of the country.

Chapter 5 Gregory's 1893 Lake Baringo &amp; Mount Kenya Expedition: ‘The Great Rift Valley’

Except where noted otherwise, the following is taken from Gregory's 1896 book (422 pages), mostly Part II. It is not intended to give a detailed resume of that gripping account, but to outline what Gregory achieved and some of the difficulties he faced, the first of which had been surviving the unnecessary stay in the notorious malarial inland zone during the previous expedition. In this zone, the annual death rate among Europeans was 23%. In Mombasa, an island good for health, Gregory confirmed his plan to mount his own expedition to the Rift Valley. He telegraphed home to his family for ‘a small sum of money’ (Flower in Gregory 1894, p. 515; Nicholson 1932), almost certainly much less than £50, for his annual salary was less than £200. He was determined not to burden the Museum with unexpected expenses, but he did obtain carte blanche from the NHM trustees to act in whatever way he thought best, consistent with his own safety, as his enthusiasm was well known in the NHM and there were concerns that he might become reckless (Flower, op. cit.). Many years later, J. R. Norman (1896–1944) revealed that Charles Davies Sherborn (1861–1942), an old and intimate colleague of Gregory's at the NHM, had had a considerable tussle with Whitehall on Gregory's behalf in order to allow Gregory to mount his own expedition, although neither Flower nor Gregory made any reference to this (Norman 1944). The probable reason is given below. Despite his meagre finances (his salary and some small savings) he was helped by having the pick of the unused stores and equipment from the abandoned expedition. Without these he would not have been able to proceed. No other European would accompany him. He had learnt a great deal from the difficulties of the Villiers …