Central North Africa Research Articles

Iron oxide minerals in dust-source sediments from the Bodélé Depression, Chad: Implications for radiative properties and Fe bioavailability of dust plumes from the Sahara

Abstract Atmospheric mineral dust can influence climate and biogeochemical cycles. An important component of mineral dust is ferric oxide minerals (hematite and goethite) which have been shown to influence strongly the optical properties of dust plumes and thus affect the radiative forcing of global dust. Here we report on the iron mineralogy of dust-source samples from the Bodele Depression (Chad, north-central Africa), which is estimated to be Earth’s most prolific dust producer and may be a key contributor to the global radiative budget of the atmosphere as well as to long-range nutrient transport to the Amazon Basin. By using a combination of magnetic property measurements, Mossbauer spectroscopy, reflectance spectroscopy, chemical analysis, and scanning electron microscopy, we document the abundance and relative amounts of goethite, hematite, and magnetite in dust-source samples from the Bodele Depression. The partition between hematite and goethite is important to know to improve models for the radiative effects of ferric oxide minerals in mineral dust aerosols. The combination of methods shows (1) the dominance of goethite over hematite in the source sediments, (2) the abundance and occurrences of their nanosize components, and (3) the ubiquity of magnetite, albeit in small amounts. Dominant goethite and subordinate hematite together compose about 2% of yellow-reddish dust-source sediments from the Bodele Depression and contribute strongly to diminution of reflectance in bulk samples. These observations imply that dust plumes from the Bodele Depression that are derived from goethite-dominated sediments strongly absorb solar radiation. The presence of ubiquitous magnetite (0.002–0.57 wt%) is also noteworthy for its potentially higher solubility relative to ferric oxide and for its small sizes, including PM

Bockmann, Ralf: Capital continuous. A Study of Vandal Carthage and Central North Africa from an Archaeological Perspective

<b>Bockmann, Ralf:</b> <i>Capital continuous</i>. A Study of Vandal Carthage and Central North Africa from an Archaeological Perspective

Evaluation of the aerosol vertical distribution in global aerosol models through comparison against CALIOP measurements: AeroCom phase II results.

The ability of 11 models in simulating the aerosol vertical distribution from regional to global scales, as part of the second phase of the AeroCom model intercomparison initiative (AeroCom II), is assessed and compared to results of the first phase. The evaluation is performed using a global monthly gridded data set of aerosol extinction profiles built for this purpose from the CALIOP (Cloud-Aerosol Lidar with Orthogonal Polarization) Layer Product 3.01. Results over 12 subcontinental regions show that five models improved, whereas three degraded in reproducing the interregional variability in Z α0-6 km, the mean extinction height diagnostic, as computed from the CALIOP aerosol profiles over the 0-6 km altitude range for each studied region and season. While the models' performance remains highly variable, the simulation of the timing of the Z α0-6 km peak season has also improved for all but two models from AeroCom Phase I to Phase II. The biases in Z α0-6 km are smaller in all regions except Central Atlantic, East Asia, and North and South Africa. Most of the models now underestimate Z α0-6 km over land, notably in the dust and biomass burning regions in Asia and Africa. At global scale, the AeroCom II models better reproduce the Z α0-6 km latitudinal variability over ocean than over land. Hypotheses for the performance and evolution of the individual models and for the intermodel diversity are discussed. We also provide an analysis of the CALIOP limitations and uncertainties contributing to the differences between the simulations and observations.

Climatic change controls productivity variation in global grasslands.

Detection and identification of the impacts of climate change on ecosystems have been core issues in climate change research in recent years. In this study, we compared average annual values of the normalized difference vegetation index (NDVI) with theoretical net primary productivity (NPP) values based on temperature and precipitation to determine the effect of historic climate change on global grassland productivity from 1982 to 2011. Comparison of trends in actual productivity (NDVI) with climate-induced potential productivity showed that the trends in average productivity in nearly 40% of global grassland areas have been significantly affected by climate change. The contribution of climate change to variability in grassland productivity was 15.2–71.2% during 1982–2011. Climate change contributed significantly to long-term trends in grassland productivity mainly in North America, central Eurasia, central Africa, and Oceania; these regions will be more sensitive to future climate change impacts. The impacts of climate change on variability in grassland productivity were greater in the Western Hemisphere than the Eastern Hemisphere. Confirmation of the observed trends requires long-term controlled experiments and multi-model ensembles to reduce uncertainties and explain mechanisms.

Evolutionary history ofGymnocarpos(Caryophyllaceae) in the arid regions from North Africa to Central Asia

Gymnocarpos has only about ten species distributed in the arid regions of Asia and Africa, but it exhibits a geographical disjunction between eastern Central Asia and western North Africa and Minor ...

Norms, Legitimacy and Power: Rule of Law Reform in Authoritarian Countries

This paper examines rule of law assistance to authoritarian countries by providing a broad outline of multilateral and bilateral support to countries in Central Asia and North Africa. The main point of examination is the type and form of rule of law that is promoted. The outline of donor assistance is predominantly a formalist and an institutionalist one by looking at concrete examples of donor assistance in terms of themes, sectors and institutional support areas, while not presuming the reach of laws and institutions. Rather, the examination centres on donors and donor-client interactions.

Late Permian mafic rocks identified within the Doba basin of southern Chad and their relationship to the boundary of the Saharan Metacraton

AbstractThe Doba gabbro was collected from an exploration well through the Cretaceous Doba basin of southern Chad. The gabbro is composed mostly of plagioclase, clinopyroxene and Fe–Ti oxide minerals and displays cumulus mineral textures. Whole-rock40Ar–39Ar step-heating geochronology yielded a Late Permian plateau age of 257 ± 1 Ma. The major and trace elemental geochemistry shows that the gabbro is tholeiitic in composition and has trace element ratios (i.e. La/YbN&gt; 7; Sm/YbPM&gt; 3.4; Nb/Y &gt; 1; Zr/Y &gt; 5) indicative of a basaltic melt derived from a garnet-bearing mantle source. The moderately enriched Sr–Nd isotopes (i.e. ISr= 0.70495 to 0.70839; ɛNd(T)= −1.0 to −1.3) fall within the mantle array (i.e. OIB-like) and are similar to other Late Permian plutonic rocks of North-Central Africa (i.e. ISr= 0.7040 to 0.7070). The enriched isotopic composition of the Doba gabbro contrasts with the more depleted compositions of the spatially associated Neoproterozoic post-Pan-African within-plate granites. The contrasting Nd isotope composition between the older within-plate granites and the younger Doba gabbro indicates that different mantle sources produced the rocks and thus may mark the southern boundary of the Saharan Metacraton.

Azimuthal anisotropy beneath north central Africa from shear wave splitting analyses

AbstractThis study represents the first multistation investigation of azimuthal anisotropy beneath the interior of north central Africa, including Libya and adjacent regions, using shear wave splitting (SWS) analysis. Data used in the study include recently available broadband seismic data obtained from 15 stations managed by the Libyan Center for Remote Sensing and Space Science, and those from five other stations at which data are publicly accessible. A total of 583 pairs of high‐quality SWS measurements utilizing the PKS, SKKS, and SKS phases demonstrate primarily N‐S fast orientations with an average splitting delay time of approximately 1.2 s. An absence of periodic azimuthal variation of the observed splitting parameters indicates the presence of simple anisotropy, and lack of correlation between surficial features and the splitting parameters suggests that the origin of the observed anisotropy is primarily asthenospheric. This conclusion is enhanced by nonperiodic azimuthal variation of the splitting parameters observed at one of the stations located near the boundary of areas with different anisotropic properties. We interpret the observed anisotropy to be the consequence of northward movement of the African plate relative to the asthenosphere toward the Hellenic and Calabrian subduction zones. Local variance in fast orientations may be attributable to flow deflection by the northern edge of the African continental root. The observations provide critical and previously lacking constraints on mantle dynamic models in the vicinity of the convergent boundary between the African and Eurasian plates.

Vulnerability Mapping for Water Stress in Kerala

Researchers on global water scarcity analysis concluded that a large share of the world population—nearly two-thirds—will be affected by water scarcity over the next several decades (Shiklomanov 1991; Raskin et al. 1997; Alcamo et al. 1997; Seckler et al. 2003 ; Vorosmarty et al. 2000; Wallace 2000; Wallace and Gregory 2002). The most obvious conclusion from these analyses is that water will be scarce in areas with low rainfall and relatively high population density. Many countries in the arid areas of the world, particularly Central and West Asia and North Africa, are already close to, or below the 1,000 m/capita/year threshold and therefore, this is the part of the world that is most definitely water scarce. The Intergovernmental Panel on Climate Change (IPCC [2007]) points out that water impacts due to climate change are key for all sectors and regions, resulting in decreasing water availability and increased drought in midand low-latitudes exposing hundreds and millions of people to increased water stress. As the human demand for water stress increases and competition among water-utilizing sectors intensifies, water scarcity becomes apparent in many forms. The Fourth Assessment Report of the IPCC points out that freshwater availability in Asia is projected to decrease due to climate change. By the middle of the 21st century, annual average river runoff and water availability projected to decrease by 10–30 per cent, relative to 1900–70 over some dry regions in the mid-latitudes and dry tropics. Further, water availability is projected to be lower for regions supplied by water from glaciers and snow (IPCC 2007).

A rediscovered-new ‘Qanat’ system in the High Mountains of Sinai Peninsula, with Levantine reflections

Since the Achaemenid Empire in 532–332 BCE, the ‘Qanat’ became the central irrigation system in the arid and semi-arid lands. Several terms are used for ‘Qanat’ in different regions, including the Karez, Qanat, Falaj type Daudi, Qanat Romani, Fuqara (Foggara), or Khettara as known in Central Asia, Persia, Southeast Arabia, Levant, North Africa, or Morocco respectively. Typically, the ground, spring or surface water (i.e. seasonal floods or river-fed) sources feed similar irrigation system. Based on thirteen years of extensive survey and analysis work (i.e. Sinai Peninsula Research 2000–2013 CE), this paper presents a rediscovered-new Qanat system in the High Mountains of Sinai Peninsula (i.e. UNESCO World Heritage Site ‘WHS’ no. 954) under chronological open question with Levantine reflections. In 1970s CE, the present Sinaitic site of Farsh Abu A'lwan or the anciently known Farsh Shamma'a was archaeologically surveyed without a direct reference to the Qanat system in-situ. Scientifically, it is an argumentative and unique Qanat system in terms of chronology, location (region), site (local-setting), water source, size and household utility. It is the only discovered ‘Qanat’ across the Sinai, connecting the Near East and North Africa.

Gujarati Warp Ikat Resist Method: A Practitioner's Record and Translation into Cloth

ABSTRACTIkat is a traditional form of yarn preparation for weaving that is practiced in many Asian and Central Asian countries as well as Central and South America and North Africa. Artisans bind selected sections of warp or weft threads before dyeing, in order to form patterns in the cloth as it is woven on the loom. “Warp ikat” describes the process of binding the warp in a patterned way to prevent selected areas from receiving dye prior to placing the warp on the loom to weave. Similarly “weft ikat” is woven from resist-bound dyed weft threads, and “double ikat” is woven from both warp and weft-bound dyed threads. In 2009, a Fulbright senior research award enabled me to document warp resist binding in the village of Somasar, in the Surendranagar region of Gujarat, India. Master Weaver Vaghela Vitthalbhai allowed me to observe, photograph and video him at work, from winding the warp yarn, to folding it in preparation for binding, to transferring it to the binding frame and binding the warp threads according to my paper design. Over a period of weeks and repeated visits, I developed a clear idea of the exacting process that only the master weaver fully comprehends. This paper describes in detail, from an artist's perspective, the Gujarati method for warp resist and discusses subsequent studio application. Video documents and photographic records have been a valuable asset in reconstructing the process.

Infectious diseases in asylum seekers crossing Schengen borders coming to European Union

Yearly, approximately 200.000 illegal migrants cross Schengen border (SB) to EU and seek for asylum. Of them, 120.000 are coming from North and Sub-Saharan Africa, crossing Mediterranean Sea with substantial risk and direct travel-related morbidity. The aim of this communication is an overview of infectious diseases (IDs) reported by asylum centres among seekers crossing Slovakian-Ukraine border. Records of 12.435 illegal migrants and asylum seekers arriving asylum centres and refugee camps in East Slovakia, are analysed in period 2009-2013 and compared to similar centres and studies from Poland, Italy and Greece. Among 12.435 cases, 7.215 (58%) were children accompanied by 5.200 adults, coming from Middle East, central and South Asia (Iraq, Syria, Afghanistan, India, Sri Lanka, Bangladesh, Uzbekistan, Turkmenistan, Kazakhstan, Moldova, Ukraine) and North Africa (Eritrea, Ethiopia, Somalia, Sudan, etc.) Commonest acute IDs were upper respiratory infections (URTI)32% (pneumonia 12%), gastroenteritis 7%, skin and soft tissue infections (SSTI) 26% (impetigo, scabies, other ectoparasites). Intestinal parasites were found among 15% cases. Interestingly, tuberculosis (TB) was detected only in 118 patients (less than 1%), however 51% of TB cases were due to multiresistant (MDR) strains. Sporadic cases of morbilli, diphtheria and pertussis were noticed (less than 1%) during the last 4 years. Increasing number of migrants/asylum seekers has been observed during the last 10 years, those crossing SB from Ukraine to Slovakia. However, only few severe IDs, without single death were observed in Slovakia. Also, TB was very infrequent; however most of the TB cases were MDR.

Evaluation of CMIP5 continental precipitation simulations relative to satellite-based gauge-adjusted observations

Numerous studies have emphasized that climate simulations are subject to various biases and uncertainties. The objective of this study is to cross-validate 34 Coupled Model Intercomparison Project Phase 5 (CMIP5) historical simulations of precipitation against the Global Precipitation Climatology Project (GPCP) data, quantifying model pattern discrepancies and biases for both entire data distributions and their upper tails. The results of the Volumetric Hit Index (VHI) analysis of the total monthly precipitation amounts show that most CMIP5 simulations are in good agreement with GPCP patterns in many areas, but that their replication of observed precipitation over arid regions and certain sub-continental regions (e.g., northern Eurasia, eastern Russia, central Australia) is problematical. Overall, the VHI of the multi-model ensemble mean and median also are superior to that of the individual CMIP5 models. However, at high quantiles of reference data (e.g., the 75th and 90th percentiles), all climate models display low skill in simulating precipitation, except over North America, the Amazon, and central Africa. Analyses of total bias (B) in CMIP5 simulations reveal that most models overestimate precipitation over regions of complex topography (e.g. western North and South America and southern Africa and Asia), while underestimating it over arid regions. Also, while mostmore » climate model simulations show low biases over Europe, inter-model variations in bias over Australia and Amazonia are considerable. The Quantile Bias (QB) analyses indicate that CMIP5 simulations are even more biased at high quantiles of precipitation. Lastly, we found that a simple mean-field bias removal improves the overall B and VHI values, but does not make a significant improvement in these model performance metrics at high quantiles of precipitation.« less

Consanguineous Marriage and Intellectual and Developmental Disabilities among Arab Bedouins Children of the Negev Region in Southern Israel: A Pilot Study

In this article, we present data from two special education schools that serve the Arab Bedouin population in the Negev region in southern Israel. Data were collected on 221 children (53.8% female and 46.2% male) with moderate and severe intellectual and developmental disability (IDD) in order to assess the extent of consanguineous background in these children. Findings showed that 61.5% of all the participants were offspring of parents who were biologically related, both first and second cousins. Almost 70% of the participants were diagnosed with moderate IDD, 20% with severe IDD, and 10% diagnosed with other developmental disorders. It is recommended to further investigate this population for a more detailed history and specific genetic disorders for appropriate genetic counseling for those already married and also to focus public health efforts to decrease the rate of marriages between relatives. Consanguinity is a well-known risk factor for genetic disorders, including diseases and syndromes that present with intellectual and developmental disabilities. This is due to autosomal recessive disorders and also other inherited disorders. The vast majority of the behavioral genetics studies, which for the most part have focused on twins and adoptees (1, 2) have been conducted in highly industrialized western societies such as the United States and Northern European countries. Despite the important and influential research undertaken on the impact of genetics and consanguineous marriage and the extent to which public awareness has been raised by these findings, only a limited number of investigations have been carried out in collective, non-western societies (e.g., Africa, Asia, and the Middle East) and there is scant empirical evidence regarding the genetic influence of consanguineous marriage in these societies. In these societies, consanguineous marriage is a common feature. There is, for example, a long tradition of such marriages in Japan, India, Sudani tribes, and Arab societies (3–8). Consanguineous marriage is also commonplace in the population of about 200,000 Bedouin Arabs living in the Negev desert in the south of Israel. Studies conducted in Indian rural and urban populations showed a higher frequency of consanguineous marriages in rural compared with urban communities (9, 10). One study (11) showed that about 50% of all marriages in the rural population were consanguineous marriages with 52.6% of these consanguineous marriages involving first cousin; whereas, in the urban area, consanguineous marriages accounted for about 30% of the total number of marriages, with 60.9% of these marriages involving first cousin relationships. Research indicates that a large segment of the world population practices certain forms of “inbreeding.” According to Bittles (5), 20–50% of all marriages occur between biologically related people in parts of Central, South, and West Asia and North Africa. The most popular matches are between first cousins, double first cousins (where the spouses share both sets of grandparents), or uncles and nieces. Although less than 1% of marriages are consanguineous in North America and Europe, up to 10% of marriages in East and West Africa and South America are between kin. The percentages could also be high in rapidly growing populations in Middle Africa, the Caribbean, Central America, East Asia, and Southeast Asia, for which no reliable figures exist. Changes in culture and the influence of the Western World also affect the rate of consanguineous marriage resulting in a decrease today (12). Among parents of 14,237 newborns in Bahrain in 2008–2009, the total consanguinity and first cousin marriage rates over a period of 4 months in 2008 were 10.9 and 6.9% respectively; while during all of 2009 the rates were 11.4 and 6.8% respectively (12). Compared with earlier data, first cousin marriage rates in Bahrain declined from 24% to nearly 7% (12).

Exports, Imports and Economic Growth en Central and Eastern Europe (CEE) and North Africa and Middle East Countries (MENA): A Heterogeneous Dynamic Panel Data Approach

Exports, Imports and Economic Growth en Central and Eastern Europe (CEE) and North Africa and Middle East Countries (MENA): A Heterogeneous Dynamic Panel Data Approach

Hydrocarbon source rock potential and elemental composition of lower Silurian subsurface shales of the eastern Murzuq Basin, southern Libya

A shallow borehole was drilled in lower Silurian (Rhuddanian–lower Aeronian) Tanezzuft Formation siliciclastic sediments at the eastern margin of the Murzuq Basin. Shale samples were retrieved from the borehole to study their source rock potential and trace element geochemical composition. Thirty shale samples analysed from borehole CDEG-2a reveal three geochemically distinct intervals. Shales from the top (23–38 m) interval are weathered and have negligible organic content. Shales from the middle (38–42 m) interval have moderate to good organic richness (0.6–1.7 wt.% TOC) with Hydrogen Index (HI) values up to 443 mg S2/g TOC. Shales from the bottom (42–51 m) interval have poor to moderate organic richness (0.07–0.8 wt.% TOC) with HI values up to 277 mg S2/g TOC. All samples have limited source rock potential and are immature to early mature for hydrocarbon generation. It is unlikely that they have ever been buried deeper than ∼2 km. Low TOC values (<2 wt.%) together with low concentrations of uranium (<10 ppm) indicate the absence of organic-rich black shale (‘hot shale’) source rocks in the studied interval.Inorganic geochemical redox proxies (Ce-anomaly, authigenic U, Th/U, V/Cr, Ni/Co, and V/Sc) indicate that the lower Silurian Tanezzuft Formation shales from borehole CDEG-2a were deposited under oxic bottom waters, explaining their relatively low TOC values. Deposition took place in a shallow marine environment, in a proximal position with regard to an early Silurian palaeo-shoreline. This combined Rock-Eval pyrolysis and whole-rock geochemical study provides new insights into the Silurian source rock distribution and hydrocarbon prospectivity in central North Africa.

The rivers of Africa: witness of climate change and human impact on the environment

AbstractIn this paper, we study the impact of climate change on river regimes in several parts of Africa, and we look at the most probable causes of these changes either climatically or anthropogenically driven. We study time series of updated monthly and annual runoff of rivers of North Africa, West Africa (Sahelian and humid tropical regions) and Central Africa, including the largest river basins: Niger and Volta rivers in West Africa, and Congo and Ogooue rivers in Central Africa. The recent years are studied in the perspective of multi‐decadal variability. In West Africa and in a part of Central Africa, the climate has changed since 1970, and rainfall has not returned to previous annual amounts, except in Equatorial Africa. The consequences of the long‐lasting drought are, depending on the area concerned, the modification of seasonal regimes (Equatorial area), the groundwater table decrease (Tropical humid area) and the land cover degradation (Sahelian area). The increasing number of dams and of agricultural areas also plays a major role on the modification of river regimes. The population increase will continue to impact on the environment: land cover change, deforestation, agriculture and increasing number of dams will be associated with a reduction of water and sediment discharges to the sea, and major impacts on downstream ecosystems and coastal areas. It seems necessary to share with stakeholders a comprehensive approach of the water cycle from the basin to the sea, to prevent long‐lasting damages to ecosystems and infrastructures. Copyright © 2013 John Wiley &amp; Sons, Ltd.

The Effect of Diurnal Sea Surface Temperature Warming on Climatological Air–Sea Fluxes

Abstract Diurnal sea surface warming affects the fluxes of latent heat, sensible heat, and upwelling longwave radiation. Diurnal warming most typically reaches maximum values of 3°C, although very localized events may reach 7°–8°C. An analysis of multiple years of diurnal warming over the global ice-free oceans indicates that heat fluxes determined by using the predawn sea surface temperature can differ by more than 100% in localized regions over those in which the sea surface temperature is allowed to fluctuate on a diurnal basis. A comparison of flux climatologies produced by these two analyses demonstrates that significant portions of the tropical oceans experience differences on a yearly average of up to 10 W m−2. Regions with the highest climatological differences include the Arabian Sea and the Bay of Bengal, as well as the equatorial western and eastern Pacific Ocean, the Gulf of Mexico, and the western coasts of Central America and North Africa. Globally the difference is on average 4.45 W m−2. The difference in the evaporation rate globally is on the order of 4% of the total ocean–atmosphere evaporation. Although the instantaneous, year-to-year, and seasonal fluctuations in various locations can be substantial, the global average differs by less than 0.1 W m−2 throughout the entire 10-yr time period. A global heat budget that uses atmospheric datasets containing diurnal variability but a sea surface temperature that has removed this signal may be underestimating the flux to the atmosphere by a fairly constant value.

Interpretation of gravity data by the continuous wavelet transform: The case of the Chad lineament (North-Central Africa)

Abstract A slightly bended gravity high along the Chad lineament in Central North Africa is analyzed and interpreted by the continuous wavelet transform (CWT) method. We use scale normalization on the continuous wavelet transform, allowing analysis of the gravity field in order to determine the sources at different depths. By focusing on homogenous standard sources, such as sphere or cube, horizontal cylinder or prism, sheet and infinite step, we derive the relationships between the source depth and pseudo-wavenumber. Then the source depth can be recovered from tracing the maximal values of the modulus of the complex wavelet coefficients in the CWT-based scalograms that are function of the pseudo-wavenumber. The studied area includes a central gravity high up to 75 km wide, and a secondary high that occurs at the southern part of the anomaly. The interpretation of the depth slices and vertical sections of the modulus maxima of the complex wavelet coefficients allows recognition of a relatively dense terrane located at middle crustal levels (10–25 km depth). A reasonable geological model derived from the 2.5D gravity forward modelling indicates the presence of high density bodies, probably linked to a buried suture, which were thrusted up into the mid-crust during the Neo-Proterozoic terrane collisions between the Saharan metacraton and the Arabian-Nubian shield. We conclude that the Chad line delineates a first order geological boundary, missing on the geologic maps.

African Lives: An Anthology of Memoirs and Autobiographies

the delightful miniatures, impressionistic aphorisms, and intimate poems written in the manner of a poetic diary. Alice-Catherine Carls University of Tennessee at Martin David Shook. Our Obsidian Tongues. London. Eyewear Publishing. 2013. isbn 9781908998071 David Shook is quite right that, on the days when you can see them through the pollution, the volcanoes that surround Mexico City are a perfect metaphor for the city’s way of existing at once in the present and in the past. Through their lava, rock, and ash, they symbolize both origin and aftermath, and it is this sense of the city as bubbling life and dying remains that Shook explores in Our Obsidian Tongues. The poems in the collection move fluidly between original work and translations from Spanish and indigenous languages like Zapotec, and the city they circulate shifts too, as we move among butchers, kidnappers, businessmen, mango sellers, and the “celestial bouncers” of the clouds. And yet, despite its varied cast, what stands out about Shook’s Mexico City is not its voices but its silence. It is not entirely silent, of course—we are never far from the sounds of police helicopters, whining machinery, and shrieking sirens—but it is silent in that nobody speaks. Instead, the various protagonists —kidnappers and their victims, tourists, immigrants living in the United States—write letters, which sometimes mislead or arrive too late and which always go unanswered. Mouths in the book are coated with thrush “like cobwebs over tongues too seldom moved.” Lips and throats do not belong to people but to water cisterns, volcanoes, and valleys: they are parched and dry, with no hope for anything better than the next lot of acid rain. Everything feels left behind, running out or drying up: in this sense, rather than being a celebration of the city’s many voices, Our Obsidian Tongues seems to be a lament for their absence. This raises questions about how Shook sees himself here, as poet of this dust-covered metropolis and student of its tongues. To have thrown himself with such zeal into this multifaceted project of writing and rewriting, and yet for the results to read so pessimistically, seems strange. What does it mean to produce such fiery, vivid translations and at the same time to scatter them among the ash in a landscape where it seems to be too late—everything too sick, too lifeless—for speech? Whether or not Our Obsidian Tongues provides the reader with all they need in order to answer these questions (and I am not sure that it does, but neither am I sure that it wants to), it certainly impresses as a brutal, clever, and tautly crafted portrait of a city that deserves no less. Annie McDermott São Paulo Miscellaneous African Lives: An Anthology of Memoirs and Autobiographies. Geoff Wisner, ed. Boulder, Colorado. Lynne Rienner. 2013. isbn 9781588268624 In African Lives, Geoff Wisner’s selection of memoirs (inclusive of an interview, a speech, and court testimony ) and autobiographical works answers the need for a collection of “true-life narratives” about the people of Africa. The anthology contains forty-eight works of nonfiction that span the continent during various times in its turbulent history. It is an amazing anthology—a cacophony of African voices in splendid diversity as vast as the continent itself. Geographically divided into north Africa, west Africa, central Africa, east Africa, southern Africa , and South Africa, the anthology includes the works of celebrated authors, common people, and leaders who share the particular intimacies of their lives. In “Machete Season,” 74 worldliteraturetoday.org Jean-Baptiste Murangira recounts his participation in the genocide in Rwanda. In “Encounters,” Mohammed Dib (Algeria) describes his first encounters with Europeans. Nisa shares her life (with Marjorie Shostak) of hunting and gathering during the early twentieth century in Botswana. Like Nisa’s account, Tepilit Ole Saitoti’s “The Worlds of a Maasai Warrior” is moving in its simplicity, with the attendant theme of survival and longing. One of the most powerful pieces in the collection is Chimamanda Ngozi Adichie’s (Nigeria) “African ‘Authenticity’ and the Biafran Experience .” Echoing Chinua Achebe and Ngugi wa Thiong’o, among others, Adichie writes, “The problem with stereotypes . . . in literature...