Judith Syombua Mbau

Pan-African phylogeny of Mus (subgenus Nannomys) reveals one of the most successful mammal radiations in Africa

BackgroundRodents of the genus Mus represent one of the most valuable biological models for biomedical and evolutionary research. Out of the four currently recognized subgenera, Nannomys (African pygmy mice, including the smallest rodents in the world) comprises the only original African lineage. Species of this subgenus became important models for the study of sex determination in mammals and they are also hosts of potentially dangerous pathogens. Nannomys ancestors colonized Africa from Asia at the end of Miocene and Eastern Africa should be considered as the place of their first radiation. In sharp contrast with this fact and despite the biological importance of Nannomys, the specimens from Eastern Africa were obviously under-represented in previous studies and the phylogenetic and distributional patterns were thus incomplete.ResultsWe performed comprehensive genetic analysis of 657 individuals of Nannomys collected at approximately 300 localities across the whole sub-Saharan Africa. Phylogenetic reconstructions based on mitochondrial (CYTB) and nuclear (IRBP) genes identified five species groups and three monotypic ancestral lineages. We provide evidence for important cryptic diversity and we defined and mapped the distribution of 27 molecular operational taxonomic units (MOTUs) that may correspond to presumable species. Biogeographical reconstructions based on data spanning all of Africa modified the previous evolutionary scenarios. First divergences occurred in Eastern African mountains soon after the colonization of the continent and the remnants of these old divergences still occur there, represented by long basal branches of M. (previously Muriculus) imberbis and two undescribed species from Ethiopia and Malawi. The radiation in drier lowland habitats associated with the decrease of body size is much younger, occurred mainly in a single lineage (called the minutoides group, and especially within the species M. minutoides), and was probably linked to aridification and climatic fluctuations in middle Pliocene/Pleistocene.ConclusionsWe discovered very high cryptic diversity in African pygmy mice making the genus Mus one of the richest genera of African mammals. Our taxon sampling allowed reliable phylogenetic and biogeographic reconstructions that (together with detailed distributional data of individual MOTUs) provide a solid basis for further evolutionary, ecological and epidemiological studies of this important group of rodents.

Evolutionary history and species diversity of African pouched mice (Rodentia: Nesomyidae: Saccostomus)

We explore diversity of African pouched mice, genus Saccostomus (Rodentia, Nesomyidae), by sampling molecular and morphological variation across their continental‐scale distribution in southern and eastern African savannahs and woodlands. Both mitochondrial (cytochrome b) and nuclear DNA (IRBP, RAG1) as well as skull morphology confirm the distinction between two recognized species, S. campestris and S. mearnsi, with disjunct distribution in the Zambezian and Somali–Maasai bioregions, respectively. Molecular dating suggests the divergence of these taxa occurred in the Early Pliocene, 3.9 Ma before present, whereas the deepest divergences within each of them are only as old as 2.0 Ma for S. mearnsi and 1.4 Ma for S. campestris. Based on cytochrome b phylogeny, we defined five clades (three within S. campestris, two in S. mearnsi) whose species status was considered in the light of nuclear DNA markers and morphology. We conclude that S. campestris group consists of two subspecies S. campestris campestris (Peters, 1846; comprising two cytochrome b clades) and S. campestris mashonae (de Winton, 1897) that are moderately differentiated, albeit distinct in IRBP and skull form. They likely hybridize to a limited extent along the Kafue–Zambezi Rivers. Saccostomus mearnsi group consists of two species, S. mearnsi (Heller, 1910) and S. umbriventer (Miller, 1910), that are markedly differentiated in both nuclear markers and skull form and may possibly co‐occur in south‐western Kenya and north‐eastern Tanzania. Analysis of historical demography suggests both subspecies of S. campestris experienced population expansion dated to the Last Glacial. In the present range of S. campestris group, the distribution modelling suggests a moderate fragmentation of suitable habitats during the last glacial cycle, whereas in the range of S. mearnsi group it predicts substantial shifts of its occurrence in the same period.

Non-timber forest products and their contribution to households income around Falgore Game Reserve in Kano, Nigeria

IntroductionIn the recent decades, there has been growing interest in the contribution of non-timber forest products (NTFPs) to livelihoods, development, and poverty alleviation among the rural populace. This has been prompted by the fact that communities living adjacent to forest reserves rely to a great extent on the NTFPs for their livelihoods, and therefore any effort to conserve such resources should as a prerequisite understand how the host communities interact with them.MethodsMultistage sampling technique was used for the study. A representative sample of 400 households was used to explore the utilization of NTFPs and their contribution to households’ income in communities proximate to Falgore Game Reserve (FGR) in Kano State, Nigeria. Descriptive statistics and logistic regression analysis were used to analyze and summarize the data collected.ResultsThe findings reveal that communities proximate to FGR mostly rely on the reserve for firewood, medicinal herbs, fodder, and fruit nuts for household use and sales. Income from NTFPs accounts for 20–60% of the total income of most (68%) of the sampled households. The utilization of NTFPs was significantly influenced by age, sex, household size, main occupation, distance to forest and market.ConclusionsThe findings suggest that NTFPs play an important role in supporting livelihoods, and therefore provide an important safety net for households throughout the year particularly during periods of hardship occasioned by drought. It is suggested that stakeholders should prioritize technical and financial support programs on agricultural value addition and handcrafts that would promote off-farm income generating activities, in addition, provision of alternative domestic cooking energy such as biogas in communities proximate to FGR in order to reduce pressure relating to fuelwood gathering from the forest, this will help to improve forest resources quality.

Impacts of long-term land-use changes on herd size and mobility among pastoral households in Amboseli ecosystem, Kenya

IntroductionLong-term changes in rangeland ecosystems of the world have impacted on the livestock production, a key livelihood strategy in these areas. This paper presents perceptions of the pastoral community on the dynamics of pastoral livelihoods under three land-use types namely nomadic, semi-nomadic, and sedentary in Amboseli ecosystem located in southern Kenya. Structured questionnaire was used to collect data concerning household livestock herds, perceived livestock trends and their causes, importance of migration, sedentarization, and land subdivision, and were administered to respondents randomly selected from the three land-use types.ResultsThe study shows that the livestock herd size was higher in nomadic (117.1) and lower in sedentary (56.6) land-use site. The majority of the respondents in nomadic (79%), semi-nomadic (73%), and sedentary (64%) reported a declining trend in household herd size. The declines were mostly attributed to recurrent droughts and loss of grazing lands.ConclusionsPastoralism remains an important livelihood strategy to majority of households in the study area; therefore, to achieve sustainable livelihood strategies, grazing lands should be maintained.