Tanzanian Villages Research Articles

The lethal effect of soap on Schistosoma mansoni cercariae in water.

Schistosomiasis is a parasitic disease which is spread through skin contact with water containing Schistosoma cercariae. Drug treatment has been the main control method, but it does not prevent reinfection. The use of soap can be a complementary measure to reduce transmission. Therefore, this study investigates the quantitative effect of different soaps on the mortality of Schistosoma mansoni cercariae. Four soaps including two powder soaps (Kleesoft and Omo) and two bar soaps (B29 and Rungu) which are used in a schistosomiasis-endemic Tanzanian village were studied. S. mansoni cercariae were exposed to powder soaps of 0 (control), 10, 50, 75, 100 and 1000 mg/L and to bar soaps of 0 (control), 100, 500 and 1000 mg/L. The highest concentration of 1000 mg/L was selected based on the laboratory-estimated average soap concentration during handwashing. Cercariae were observed under a microscope after 0, 5, 15, 30, 45 and 60 minutes of exposure to determine their survival. All four soaps can kill S. mansoni cercariae and this lethal effect was related to soap concentration and exposure time. At the highest concentration of 1000 mg/L, all cercariae were dead at 5 minutes post-exposure with two powder soaps and Rungu, while 100% cercarial death was achieved between 5 minutes to 15 minutes for B29. Almost all cercariae survived after being exposed to 10 mg/L powder soaps and 100 mg/L bar soaps for 60 minutes. Powder soaps were more lethal than bar soaps. Considering the widely varying concentrations of soap during real-world hygiene activities and the necessity for a very high soap concentration to eliminate all cercariae in a short 5-minute exposure, providing the efficacy of soap in preventing schistosomiasis becomes challenging. Future studies should investigate whether soap can influence alternative mechanisms such as making cercariae unable to penetrate the skin, thereby providing protection.

Friends near and afar, through thick and thin: Comparing contingency of help between close-distance and long-distance friends in Tanzanian fishing villages

Humans form and maintain friendships across long distances, which can provide access to non-local resources and support against large shocks that affect the entire local community. However, there may be a greater risk of defection in long-distance friendships, as monitoring for defection is more difficult at greater distances; accordingly, help between long-distance friends may be more explicitly contingent than between close-distance friends. We interviewed 918 participants from 21 fishing villages in Tanzania about whether they had received help in the form of a gift or loan from a friend living in their village and a friend living in a neighboring village. As there are local expectations that loans will be repaid but gifts will not, we predicted that close-distance friends would be more likely to help with gifts, whereas long-distance friends would be more likely to help with loans. Contrary to our predictions, gifts and loans between close- and long-distance friends were similar in kind and amount, though close-distance friends provided help more frequently, possibly because close-distance friends are more likely to meet frequently and belong to the same religious congregation. These results indicate that long-distance friendships are an important, and likely robust, strategy for managing risk and accessing more resources.

Pedagogical features of interactive apps for effective learning of foundational skills

Interactive apps are commonly used to support the acquisition of foundational skills. Yet little is known about how pedagogical features of such apps affect learning outcomes, attainment and motivation—particularly when deployed in lower‐income contexts, where educational gains are most needed. In this study, we analyse which app features are most effective in supporting the acquisition of foundational literacy and numeracy skills. We compare five apps developed for the Global Learning XPRIZE and deployed to 2041 out‐of‐school children in 172 remote Tanzanian villages. A total of 41 non‐expert participants each provided 165 comparative judgements of the five apps from the competition, across 15 pedagogical features. Analysis and modelling of these 6765 comparisons indicate that the apps created by the joint winners of the XPRIZE, who produced the greatest learning outcomes over the 15‐month field trial, shared six pedagogical features—autonomous learning, motor skills, task structure, engagement, language demand and personalisation. Results demonstrate that this combination of features is effective at supporting learning of foundational skills and has a positive impact on educational outcomes. To maximise learning potential in environments with both limited resources and deployment opportunities, developers should focus attention on this combination of features, especially for out‐of‐school children in low‐ and middle‐income countries. Practitioner notesWhat is already known about this topic Interactive apps are becoming common to support foundational learning for children both in and out of school settings. The Global Learning XPRIZE competition demonstrates that learning apps can facilitate learning improvements in out‐of‐school children living in sub‐Saharan Africa. To understand which app features are most important in supporting learning in these contexts, we need to establish which pedagogical features were shared by the winning apps. What this paper adds Effective learning of foundational skills can be achieved with a range of pedagogical features. To maximise learning, apps should focus on combining elements of autonomous learning, motor skills, task structure, engagement, language demand and personalisation. Free Play is not a key pedagogical feature to facilitate learning within this context. Implications for practice and/or policy When developing learning apps with primary‐aged, out‐of‐school children in low‐income contexts, app developers should try to incorporate the six key features associated with improving learning outcomes. Governments, school leaders and parents should use these findings to inform their decisions when choosing an appropriate learning app for children.

Watu kama sisi: they are not ghosts, but just like us – awareness raising about albinism in Tanzanian villages

ABSTRACT People with albinism in sub-Saharan African countries have long struggled for equal rights and the understanding of society at large, fighting stigmatisation and, in numerous cases, for their lives against wrongdoings in the form of killings and other physical atrocities. This article examines the Tanzanian context and adds to the ongoing academic discourse by presenting tangible manifestations of awareness-raising and education in village communities. It summarises the efforts and results of NGOs in Northern Tanzania working with and run by persons with albinism (PWAs) and presents an analysis of both success and failure. It highlights the work of the NGO named Peacemakers for Albinism and Community (originally Albino Peacemakers). The article argues that safeguarding the vulnerable groups of PWAs remains a task at all levels of society, from remote villages via central governments to the international community; therefore, educating people about this condition – even PWAs themselves – carries the highest relevance.

Wild populations of malaria vectors can mate both inside and outside human dwellings

BackgroundWild populations of Anopheles mosquitoes are generally thought to mate outdoors in swarms, although once colonized, they also mate readily inside laboratory cages. This study investigated whether the malaria vectors Anopheles funestus and Anopheles arabiensis can also naturally mate inside human dwellings.MethodMosquitoes were sampled from three volunteer-occupied experimental huts in a rural Tanzanian village at 6:00 p.m. each evening, after which the huts were completely sealed and sampling was repeated at 11:00 p.m and 6 a.m. the next morning to compare the proportions of inseminated females. Similarly timed collections were done inside local unsealed village houses. Lastly, wild-caught larvae and pupae were introduced inside or outside experimental huts constructed inside two semi-field screened chambers. The huts were then sealed and fitted with exit traps, allowing mosquito egress but not entry. Mating was assessed in subsequent days by sampling and dissecting emergent adults caught indoors, outdoors and in exit traps.ResultsProportions of inseminated females inside the experimental huts in the village increased from approximately 60% at 6 p.m. to approximately 90% the following morning despite no new mosquitoes entering the huts after 6 p.m. Insemination in the local homes increased from approximately 78% to approximately 93% over the same time points. In the semi-field observations of wild-caught captive mosquitoes, the proportions of inseminated An. funestus were 20.9% (95% confidence interval [CI]: ± 2.8) outdoors, 25.2% (95% CI: ± 3.4) indoors and 16.8% (± 8.3) in exit traps, while the proportions of inseminated An. arabiensis were 42.3% (95% CI: ± 5.5) outdoors, 47.4% (95% CI: ± 4.7) indoors and 37.1% (CI: ± 6.8) in exit traps.ConclusionWild populations of An. funestus and An. arabiensis in these study villages can mate both inside and outside human dwellings. Most of the mating clearly happens before the mosquitoes enter houses, but additional mating happens indoors. The ecological significance of such indoor mating remains to be determined. The observed insemination inside the experimental huts fitted with exit traps and in the unsealed village houses suggests that the indoor mating happens voluntarily even under unrestricted egress. These findings may inspire improved vector control, such as by targeting males indoors, and potentially inform alternative methods for colonizing strongly eurygamic Anopheles species (e.g. An. funestus) inside laboratories or semi-field chambers.Graphical

Empowerment Through Genuine Participation: Giving Voice to the Neglected Majority

Empowerment is often a goal of community development projects aimed at poverty reduction; yet, ascertaining whether empowerment occurs can be elusive. This case study research examined the empowerment process. Thirty community partners participated in a three-year community-led initiative to improve public education in a rural northwest Tanzanian village. The initiative included capacity-building activities to enhance personal and collective agency. The findings from the analytic framework of self-determination theory indicated that the initiative simultaneously nurtured and satisfied community partners’ innate basic psychological needs of relatedness, competence and autonomy: hence affirmed their feelings of empowerment. Implications for the theory and practice are presented.

The structure of risk-sharing networks

We examine the structure of risk-sharing networks in developing countries using data from the Tanzanian village of Nyakatoke. We first show that the Nyakatoke network exhibits: (1) the “small-world” phenomenon, where two households who are not themselves risk-sharing partners are separated only by a short chain of intermediaries; (2) preferential attachment, which is a network formation process where the probability of a household receiving a partner is proportional to that household’s existing number of partners; and (3) assortative mixing, as similarly connected households tend to link to each other. We then examine the implications of these features for network performance by comparing the Nyakatoke network to simulated networks with alternative structural traits. Our simulations show that the Nyakatoke network displays optimal or near-optimal performance along multiple dimensions. In particular, the Nyakatoke network has a notable ability to withstand perturbations of multiple types, a property that none of the counterfactual networks possess.

Fitness characteristics of the malaria vector Anopheles funestus during an attempted laboratory colonization

BackgroundThe malaria vector Anopheles funestus is increasingly recognized as a dominant vector of residual transmission in many African settings. Efforts to better understand its biology and control are significantly impeded by the difficulties of colonizing it under laboratory conditions. To identify key bottlenecks in colonization, this study compared the development and fitness characteristics of wild An. funestus from Tanzania (FUTAZ) and their F1 offspring during colonization attempts. The demography and reproductive success of wild FUTAZ offspring were compared to that of individuals from one of the only An. funestus strains that has been successfully colonized (FUMOZ, from Mozambique) under similar laboratory conditions.MethodsWild An. funestus (FUTAZ) were collected from three Tanzanian villages and maintained inside an insectary at 70–85% RH, 25–27 °C and 12 h:12 h photoperiod. Eggs from these females were used to establish three replicate F1 laboratory generations. Larval development, survival, fecundity, mating success, percentage pupation and wing length were measured in the F1 -FUTAZ offspring and compared with wild FUTAZ and FUMOZ mosquitoes.ResultsWild FUTAZ laid fewer eggs (64.1; 95% CI [63.2, 65.0]) than FUMOZ females (76.1; 95% CI [73.3, 79.1]). Survival of F1-FUTAZ larvae under laboratory conditions was low, with an egg-to-pupae conversion rate of only 5.9% compared to 27.4% in FUMOZ. The median lifespan of F1-FUTAZ females (32 days) and males (33 days) was lower than FUMOZ (52 and 49 for females and males respectively). The proportion of female F1-FUTAZ inseminated under laboratory conditions (9%) was considerably lower than either FUMOZ (72%) or wild-caught FUTAZ females (92%). This resulted in nearly zero viable F2-FUTAZ eggs produced. Wild FUTAZ wings appear to be larger compared to the lab reared F1-FUTAZ and FUMOZ.ConclusionsThis study indicates that poor larval survival, mating success, low fecundity and shorter survival under laboratory conditions all contribute to difficulties in colonizing of An. funestus. Future studies should focus on enhancing these aspects of An. funestus fitness in the laboratory, with the biggest barrier likely to be poor mating.

Hybrid mosquitoes? Evidence from rural Tanzania on how local communities conceptualize and respond to modified mosquitoes as a tool for malaria control

BackgroundDifferent forms of mosquito modifications are being considered as potential high-impact and low-cost tools for future malaria control in Africa. Although still under evaluation, the eventual success of these technologies will require high-level public acceptance. Understanding prevailing community perceptions of mosquito modification is, therefore, crucial for effective design and implementation of these interventions. This study investigated community perceptions regarding genetically-modified mosquitoes (GMMs) and their potential for malaria control in Tanzanian villages where no research or campaign for such technologies has yet been undertaken.MethodsA mixed-methods design was used, involving: (i) focus group discussions (FGD) with community leaders to get insights on how they frame and would respond to GMMs, and (ii) structured questionnaires administered to 490 community members to assess awareness, perceptions and support for GMMs for malaria control. Descriptive statistics were used to summarize the findings and thematic content analysis was used to identify key concepts and interpret the findings.ResultsNearly all survey respondents were unaware of mosquito modification technologies for malaria control (94.3%), and reported no knowledge of their specific characteristics (97.3%). However, community leaders participating in FGDs offered a set of distinctive interpretive frames to conceptualize interventions relying on GMMs for malaria control. The participants commonly referenced their experiences of cross-breeding for selecting preferred traits in domestic plants and animals. Preferred GMMs attributes included the expected reductions in insecticide use and human labour. Population suppression approaches, requiring as few releases as possible, were favoured. Common concerns included whether the GMMs would look or behave differently than wild mosquitoes, and how the technology would be integrated into current malaria control policies. The participants emphasised the importance and the challenge of educating and engaging communities during the technology development.ConclusionsUnderstanding how communities perceive and interpret novel technologies is crucial to the design and effective implementation of new vector control programmes. This study offers vital clues on how communities with no prior experience of modified mosquitoes might conceptualize or respond to such technologies when deployed in the context of malaria control programmes. Drawing upon existing interpretive frames and locally-resonant analogies when deploying such technologies may provide a basis for more durable public support in the future.

Real-time dispersal of malaria vectors in rural Africa monitored with lidar.

Lack of tools for detailed, real-time observation of mosquito behavior with high spatio-temporal resolution limits progress towards improved malaria vector control. We deployed a high-resolution entomological lidar to monitor a half-kilometer static transect positioned over rice fields outside a Tanzanian village. A quarter of a million in situ insect observations were classified, and several insect taxa were identified based on their modulation signatures. We observed distinct range distributions of male and female mosquitoes in relation to the village periphery, and spatio-temporal behavioral features, such as swarming. Furthermore, we observed that the spatial distributions of males and females change independently of each other during the day, and were able to estimate the daily dispersal of mosquitoes towards and away from the village. The findings of this study demonstrate how lidar-based monitoring could dramatically improve our understanding of malaria vector ecology and control options.

Fine-scale distribution of malaria mosquitoes biting or resting outside human dwellings in three low-altitude Tanzanian villages

While malaria transmission in Africa still happens primarily inside houses, there is a substantial proportion of Anopheles mosquitoes that bite or rest outdoors. This situation may compromise the performance of indoor insecticidal interventions such as insecticide-treated nets (ITNs). This study investigated the distribution of malaria mosquitoes biting or resting outside dwellings in three low-altitude villages in south-eastern Tanzania. The likelihood of malaria infections outdoors was also assessed. Nightly trapping was done outdoors for 12 months to collect resting mosquitoes (using resting bucket traps) and host-seeking mosquitoes (using odour-baited Suna® traps). The mosquitoes were sorted by species and physiological states. Pooled samples of Anopheles were tested to estimate proportions infected with Plasmodium falciparum parasites, estimate proportions carrying human blood as opposed to other vertebrate blood and identify sibling species in the Anopheles gambiae complex and An. funestus group. Environmental and anthropogenic factors were observed and recorded within 100 meters from each trapping positions. Generalised additive models were used to investigate relationships between these variables and vector densities, produce predictive maps of expected abundance and compare outcomes within and between villages. A high degree of fine-scale heterogeneity in Anopheles densities was observed between and within villages. Water bodies covered with vegetation were associated with 22% higher densities of An. arabiensis and 51% lower densities of An. funestus. Increasing densities of houses and people outdoors were both associated with reduced densities of An. arabiensis and An. funestus. Vector densities were highest around the end of the rainy season and beginning of the dry seasons. More than half (14) 58.3% of blood-fed An. arabiensis had bovine blood, (6) 25% had human blood. None of the Anopheles mosquitoes caught outdoors was found infected with malaria parasites. Outdoor densities of both host-seeking and resting Anopheles mosquitoes had significant heterogeneities between and within villages, and were influenced by multiple environmental and anthropogenic factors. Despite the high Anopheles densities outside dwellings, the substantial proportion of non-human blood-meals and absence of malaria-infected mosquitoes after 12 months of nightly trapping suggests very low-levels of outdoor malaria transmission in these villages.

Spatial sampling for a rabies vaccination schedule in rural villages

Efforts are being made to contain rabies in Tanzania, reported in the southern highland regions, since 1954, and endemic in all districts in Tanzania currently. It has been determined that mass vaccination of at least $$70\%$$ of a domestic animal population is most effective in reducing transmission of rabies. Current vaccination campaigns in Tanzanian villages have many administrative and logistical challenges. Animals roam freely, making a full population vaccination impossible. Spatial sampling of households in villages is proposed, where optimality is measured through the distance traversed by the vaccinator by foot for vaccinating at each sampled household. The walking distance is attained by incorporating a driving network between optimally determined stopping points from which the vaccinator then walks for executing vaccinations, while ensuring the $$70\%$$ coverage of the animal population. We illustrate the sampling schemes on a real dataset using simulations. A systematic regular spatial sampling is found to be optimal. The vaccination scheme proposed, provides an effective way to manage a vaccination campaign.

Sustainable Agricultural Intensification in Four Tanzanian Villages—A View from the Ground and the Sky

Agricultural intensification based on smallholders is among many economists viewed as a necessary developmental path to ensure food security and poverty reduction in sub-Saharan Africa. Increasingly, a one-sided focus on raising productivity in cereals has been questioned on environmental grounds, with the concept of sustainable agricultural intensification (SAI) emerging from the natural sciences as a way of advancing environmental and social needs simultaneously. SAI approaches have, however, been criticized for being both conceptually and methodologically vague. This study combines socioeconomic survey data with remotely sensed land productivity data and qualitative data from four villages in Tanzania. By triangulating and comparing data collected through ground level surveys and ground-truthing with remote sensing data, we find that this combination of methods is capable of resolving some of the theoretical and methodological vagueness found in SAI approaches. The results show the problems of relying on only one type of data when studying sustainable agricultural intensification and indicate the poor environmental outcomes of cereal monocropping, even when social outcomes may be forthcoming. We identify land use practices that can be considered both socially and environmentally sustainable. Theoretically, we contribute to a further problematization of the SAI concept.

Negotiating inclusion by exclusion, or how to secure “eating” from farmland investments in Tanzania

ABSTRACT This paper challenges previous institutional analyses of conflict patterns, showing that land conflicts are more complex and unpredictable than generally assumed. It documents how the arrival of investors in a Tanzanian village has fostered local land conflicts, and explains why local leaders defended their fellow villagers in one land conflict, but discriminated against them in another. Using a local political settlement approach, I argue that studying how formal and informal institutions are structuring the distribution of power is key to explaining why local leaders have used different conflict management strategies. This paper contributes to an emerging scholarship that links the global land rush and land conflicts, insisting on the role played by Tanzanian investors. It also nuances the dominant narrative of Tanzania as a harmonious country in which ethnicity is not politically salient by showing that local actors may instrumentalize identity to produce political discrimination.

Building a Better Blogger

Jacquelyn Adams began her training career teaching high school math in Swahili in a rural Tanzanian village for two years as a Peace Corps volunteer. Upon returning to the United States, she combined her love of teaching with her B.S. degree in computer engineering to become a corporate engineering trainer. After spending a decade as a top-rated instructor, she founded a consulting company, Ristole. Adams is an IEEE Senior Member and serves as the vice chair of both the IEEE's Continuing Education Committee and Public Visibility Committee. She has received local and national recognition for her professional achievements. including Top 40 Under 40, Entrepreneurial Achievement, Outstanding Young Alumni, and Outstanding Woman in Business awards. Her blog, Lessons on Leadership (https://insight.ieeeusa.org/jacquelyn-adams/), shares leadership development tips and has become the most read column on IEEE-USA InSight. Adams also hosts the IEEE.tv channel Jacquelyn Worx, which focuses on the future of work and career development.

Women's marginalization in participatory forest management: Impacts of responsibilization in Tanzania

This paper analyses the consequences of responsibilization for women in natural resource management in Southern Tanzania. Participatory forest management (PFM) and Participatory Land Use Planning in Southern Tanzania provide a case study to interrogate how responsibilization impacts on the existing social order in a given community. As the study findings show, participatory initiatives have not fully reached rural women who are still under-represented and insufficiently equipped to participate in public decision-making, which maintains women's marginalization.In Tanzania there has been progress in community rights for forest management. Following the Forest Policy (1998) and Forest Act (2002), Tanzanian villages can establish Village Land Forest Reserves and manage and utilize natural resources for the benefit of the community. The success of decentralized forest governance depends on the interplay between power, authority and social relations. This is determined by the capacity of communities to participate and by the government's responsiveness to the people's voice.Based on our case study, women do not have equal opportunities to raise their voice like men, and women are marginalized in the decisions made about forest management and in the distribution of benefits from the natural resources with which their communities are endowed. This has policy implications in the sense that processes and structures of decentralized forest governance seem unable to address the needs of women.

Lidar reveals activity anomaly of malaria vectors during pan-African eclipse.

Yearly, a quarter billion people are infected and a half a million killed by the mosquito-borne disease malaria. Lack of real-time observational tools for continuously assessing the unperturbed mosquito flight activity in situ limits progress toward improved vector control. We deployed a high-resolution entomological lidar to monitor a half-kilometer static transect adjacent to a Tanzanian village. We evaluated one-third million insect observations during five nights, four days, and one annular solar eclipse. We demonstrate in situ lidar classification of several insect families and their sexes based on their modulation signatures. We were able to compare the fine-scale spatiotemporal activity patterns of malaria vectors during ordinary days and an eclipse to disentangle phototactic activity patterns from the circadian mechanism. We observed an increased insect activity during the eclipse attributable to mosquitoes. These unprecedented findings demonstrate how lidar-based monitoring of distinct mosquito activities could advance our understanding of vector ecology.

Perceptions of Time-Use in Rural Tanzanian Villages: Working With Gender-Sensitive Tools in Nutritional Education Meetings

Food consumption and nourishment are related to the availability and use of resources by different social groups within a country. Communities experience hunger not just due to biophysical restrictions, but also their socio-cultural conditions. For this reason, international scientific cooperation seeking to improve nourishment must be interdisciplinary and connected to disciplines covering all relevant dimensions, including hunger, health and well-being, gender, and inter-ethnic relations. Studies on constraints and drivers of food consumption in Sub-Saharan Africa indicate that although women make decisions regarding the type of meals consumed, they lack control over food production, especially on small farms. While the term gender equally is commonly found in discourses on nourishment projects, knowledge regarding gender programs and education for men in remote patriarchal villages in Eastern Africa is rare. To close this research gap, this study seeks to understand 1) basic notions of masculinities and femininities of this inter-ethnic group; and 2) how traditional knowledge can influence decisions related to Unpaid Care Work and nourishment. The case study area is inhabited by the Wagogo, a predominantly pastoralist and patrilineal tribe practicing settled agriculture or migrating to urban areas throughout Tanzania. To achieve these research goals, we explicitly develop pedagogical strategies to interact with adults living in the villages, separated into men and women. These pedagogical tools encompass Nutritional Education involving 80 participants, including female and male farmers, community leaders, primary school teachers, and health professionals. Based in time-use field of knowledge and proposed activities based on participatory methods, we established bonds of trust with the community, initiating a truly open dialogue about food consumption and decision-making. This study reinforces the need to address the ethnic identities of the researched regions in order to not just comprehend the traditions and culture, but also the food and nutrition of the indigenous people.

Soil contamination by Taenia solium egg DNA in rural villages in Kongwa district, Tanzania

ABSTRACT The presence ofTaenia solium DNA from eggs in soils around the households in four Tanzanian villages in Kongwa district were analysed in relation to seasonal fluctuations and infection risk implications. A total of 192 pooled soil samples from five sampling points per household were examined by droplet digital Polymerase Chain Reaction (ddPCR) from 96 pig-keeping households both during the dry and rainy seasons. The pooled samples were first processed by a flotation-double sieving technique, followed by screening for worm DNA employing universal primers targeting the mitochondrial cytochrome c oxidase subunit I (cox1) gene of human taeniid species and some other helminths. All DNA positive samples were later confirmed by a specific ddPCR probe assay targeting the mitochondrial cox1 gene of T. solium. A total of 17.2% (n = 33) samples were positive with the universal ddPCR, whereas T. solium DNA was confirmed by the specific ddPCR only in 3.1% (n = 3) of the surveyed households. The detection of T. solium DNA in this study spells out a low risk of exposure to T. solium eggs from contaminated household soil. Based on our results, ddPCR seems to be a promising technology for screening T. solium eggs in soil.

In-group favouritism and social norms: Public goods experiments in Tanzania

The inhabitants of two Tanzanian villages participate in a public goods experiment. Each village consists of multiple sub-villages. Villagers share a social norm of cooperation at the village level. We put emphasis on the sub-village identity in the experiments, and let individuals from the same or from various sub-villages to be matched into a group. In-group favouritism predicts that participants cooperate more when they are in a group from the same sub-village (In-group treatment) than when they are in a group composed of members from different sub-villages (Out-group treatment). We reject this hypothesis. Participants’ expectations of contributions of others do not differ across treatments. However, they respond differently to own expectations across treatments. They contribute on average more than what they expect others to contribute in the Out-group treatment, but less than what they expect others to contribute in the In-group treatment. This is consistent with the activation of the village-level social norm only in the context in which the norm exists, in interactions with other villagers. We emphasise that existing social norms of cooperation need to be considered when making a specific sub-group identity salient with the aim to promote public goods provision.