Search results for "Tanzania"
showing 10 items of 86 documents
Divergent parasite infections in sympatric cichlid species in Lake Victoria
2018
Parasitism has been proposed as a factor in host speciation, as an agent affecting coexistence of host species in species-rich communities and as a driver of post-speciation diversification. Young adaptive radiations of closely related host species of varying ecological and genomic differentiation provide interesting opportunities to explore interactions between patterns of parasitism, divergence and coexistence of sympatric host species. Here, we explored patterns in ectoparasitism in a community of 16 fully sympatric cichlid species at Makobe Island in Lake Victoria, a model system of vertebrate adaptive radiation. We asked whether host niche, host abundance or host genetic differentiatio…
Argyrella richardsiae, a new species of Melastomataceae from the wet miombo woodlands of south-central Africa
2017
A new species from the wet miombo woodlands of Tanzania and Angola, Argyrella richardsiae Veranso-Libalah & G.Kadereit, sp. nov. (Melastomataceae, Melastomateae), is described and illustrated. Although the widespread Argyrella canescens also occurs in Tanzania and northeastern Angola, A. richardsiae is morphologically most similar to Argyrella bambutorum known only from the Northwest of Cameroon, but differs by its indumentum of glandular trichomes on the entire plant (versus a mixture of stellate and glandular trichomes in other species of Argyrella), leaf-blades with serrulate margins (versus entire margins in A. bambutorum) and lateral nerves that become faint mid-way and never reach…
A case study of the coconut crab Birgus latro on Zanzibar highlights global threats and conservation solutions
2021
Abstract The coconut crab Birgus latro, the largest terrestrial decapod, is under threat in most parts of its geographical range. Its life cycle involves two biomes (restricted terrestrial habitats near the coast, and salt water currents of the tropical Indian and Pacific Oceans). Its dependence on coastal habitat means it is highly vulnerable to the habitat destruction that typically accompanies human population expansion along coastlines. Additionally, it has a slow reproductive rate and can reach large adult body sizes that, together with its slow movement when on land, make it highly susceptible to overharvesting. We studied the distribution and population changes of coconut crabs at 15…
Genomics of speciation and introgression in Princess cichlid fishes from Lake Tanganyika.
2016
How variation in the genome translates into biological diversity and new species originate has endured as the mystery of mysteries in evolutionary biology. African cichlid fishes are prime model systems to address speciation-related questions for their remarkable taxonomic and phenotypic diversity, and the possible role of gene flow in this process. Here, we capitalize on genome sequencing and phylogenomic analyses to address the relative impacts of incomplete lineage sorting, introgression and hybrid speciation in the Neolamprologus savoryi-complex (the 'Princess cichlids') from Lake Tanganyika. We present a time-calibrated species tree based on whole-genome sequences and provide strong ev…
Archaeology and ichnology at Gombore II-2, Melka Kunture, Ethiopia: everyday life of a mixed age hominin group 700,000 years ago
2018
AbstractWe report the occurrence at 0.7 million years (Ma) of an ichnological assemblage at Gombore II-2, which is one of several archaeological sites at Melka Kunture in the upper Awash Valley of Ethiopia, 2000 m asl. Adults and children potentially as young as 12 months old left tracks in a silty substrate on the shore of a body of water where ungulates, as well as other mammals and birds, congregated. Furthermore, the same layers contain a rich archaeological and palaeontological record, confirming that knapping was taking place in situ and that stone tools were used for butchering hippo carcasses at the site. The site gives direct information on hominin landscape use at 0.7 Ma and may p…
Dissenting voices in a consenting village: lessons from implementation of free, prior and informed consent at a REDD+ pilot in Tanzania
2020
Free, prior and informed consent (FPIC) is a key institutional tool in meeting social safeguards. Its implementation ensures respect of the local people's rights in an intervention. This paper presents a case of FPIC implementation at a REDD+ pilot site. Data were obtained through key informant interviews and focus group discussions with proponents and village members of the Lindi REDD+ project. Findings indicate that the inclusive approach to FPIC by taking the consultations to the hamlet level did not deliver a flawless process. The consent decision was reached by a majority vote, not consensus. There was some dissent, prompting the early establishment of project implementation committees…
Predictors of mortality in HIV-infected patients starting antiretroviral therapy in a rural hospital in Tanzania
2008
Background Studies of antiretroviral therapy (ART) programs in Africa have shown high initial mortality. Factors contributing to this high mortality are poorly described. The aim of the present study was to assess mortality and to identify predictors of mortality in HIV-infected patients starting ART in a rural hospital in Tanzania. Methods This was a cohort study of 320 treatment-naïve adults who started ART between October 2003 and November 2006. Reliable CD4 cell counts were not available, thus ART initiation was based on clinical criteria in accordance with WHO and Tanzanian guidelines. Kaplan-Meier models were used to estimate mortality and Cox proportional hazards models to identify p…
Variable geographic distribution of Blastocystis subtypes and its potential implications.
2012
Blastocystis is a common intestinal micro-eukaryote found in both humans and non-human hosts and known to be genetically very diverse. It has been divided into numerous subtypes (STs), nine of which have been identified in humans to date. Surveys of ST prevalence have started to emerge over the past few years but to date no data are available for any African country except Egypt and Tanzania. In this study, we determined the prevalence of Blastocystis STs in populations from Libya, Liberia and Nigeria, as well as expanding the dataset available for the UK. A total of 356 Blastocystis STs were identified in this study, 271 from the UK, 38 from Libya, 25 from Liberia and 22 from Nigeria. SSU …
Antiretroviral treatment reverses HIV-associated anemia in rural Tanzania.
2011
Background HIV-associated anemia is common and associated with poor prognosis. However, its response to antiretroviral treatment (ART) in rural Africa is poorly understood. Methods HIV-infected adults (≥15 years) who enrolled in HIV care at Haydom Lutheran Hospital in northern Tanzania were included in the study. The effect of ART (zidovudine/stavudine + lamivudine + efavirenz/nevirapine) on HIV-associated anemia was studied in a subset of patients who were anemic at the time they started ART and had a follow-up hemoglobin measurement 12 months later. Pregnant women were excluded from the study, as were women who had given birth within the past 6 weeks. Anemia was defined as hemoglobin <12 …
Virological efficacy and emergence of drug resistance in adults on antiretroviral treatment in rural Tanzania
2009
Background Virological response to antiretroviral treatment (ART) in rural Africa is poorly described. We examined virological efficacy and emergence of drug resistance in adults receiving first-line ART for up to 4 years in rural Tanzania. Methods Haydom Lutheran Hospital has provided ART to HIV-infected patients since October 2003. A combination of stavudine or zidovudine with lamivudine and either nevirapine or efavirenz is the standard first-line regimen. Nested in a longitudinal cohort study of patients consecutively starting ART, we carried out a cross-sectional virological efficacy survey between November 2007 and June 2008. HIV viral load was measured in all adults who had completed…