Search

Background: While school-aged children in low- and middle-income countries remain highly exposed to acute infections, programs targeting this age group remain limited in scale and scope. In this paper, we evaluate the impact of a new and comprehensive primary school-based health intervention program on student-reported morbidity and anthropometric outcomes in Lusaka, Zambia. Methods: A prospective matched control study identified 12 classes in 7 schools for the intervention and 12 classes in 7 matched schools as controls. Teachers in intervention schools were trained to deliver health lessons and to refer sick students to care. In addition, vitamin A and deworming medication were biannually administered to intervention students. The primary study outcome was student-reported morbidity. Secondary outcomes were weight, height, health knowledge, and absenteeism. Multivariable linear and logistic regression models were used to estimate program impact. Results: 380 students ages 4–16 were enrolled in the study in 2015, and 97% were followed up at endline in 2016. The intervention decreased the adjusted odds of self-reported acute illnesses by 38% (95% CI: 0.48, 0.77) and the adjusted odds of stunting by 52% (95% CI: 0.26, 0.87). It also increased health knowledge by 0.53 standard deviations (95% CI: 0.24, 0.81). No impact was found on weight (adjusted mean difference β = 0.17, 95% CI: - 1.11, 1.44) and student absenteeism (adjusted odds ratio (aOR) = 0.89, 95% CI: 0.60, 1.33). Conclusion: The results presented in this paper suggest that comprehensive school-based health programs may offer a highly effective way to improve students’ health knowledge as well as their health status. Given their low cost, a more general adoption and implementation of such programs seems recommendable. Trial registration: ClinicalTrials.gov Identifier: . [ABSTRACT FROM AUTHOR]

Background: Crime and violence causes massive disruptions to the health, survival and development of populations. In South Africa, incredibly high rates of crime and violence are noted. The country also has a very large youth population whose health, survival and development are key to economic growth. Among other efforts to encourage healthy youth development and the promotion of social activities such as sports, youth groups, choirs and so forth. This study examines the relationship between perceived community safety and the uptake of social activities among youth in South Africa. Data and methods: This paper uses data from the National Youth Lifestyle Survey (2008) with an unweighted sample of 4,391 youth (age12-22 years old). Using chi-square and logistic regression analysis the association between perceived community safety and social activity participation are tested. Findings: The results indicate that youth participation in social activities in South Africa is high (55% of males and 45% of females). Among males, the most prominent activity is sports (51.8%), while for females there is high participation in choir and singing groups (55.68%). More than 50% of males perceive their communities as risky while less than half of females feel the same. Male youth are more likely to participate in social activities if they perceive their communities as risky (OR = 1.04). Females (OR = 0.83), youth have a negative view of their future (OR = 0.43) are less likely to participate in social activities. Conclusions: There exists an association between youth’s perception of community safety and their participation in social activities. Whether sports and groups are protective or enabling environments for youth from unsafe communities is moot. More in-depth research is needed on why youth participate in these clubs and groups to truly understand the role of social activities in South African societies. [ABSTRACT FROM AUTHOR]

Background: The population of Ghana is increasingly becoming urbanized with about 70% of the estimated 27 million people living in urban and peri-urban areas. Nonetheless, eight out of the ten regions in Ghana remain predominantly rural where only 32% of the national health sector workforce works. Moreover, the rural-urban disparities in the density of health tutors (staff responsible for pre-service training of health professionals) are enormous. This paper explores perceived needs of health tutors in rural and urban health training institutions in Ghana. Methods: This is a descriptive qualitative study conducted in the Greater Accra and Northern regions of Ghana. The Study used the deductive thematic and sub-thematic analysis approaches. Five health training institutions were randomly sampled, and 72 tutors engaged in separate focus group discussions with an average size of 14 participants per group in each training institution. Results: Perceived rural-urban disparities among health tutors were found in the payment of extra duty allowances; school infrastructure including libraries and internet connectivity; staff accommodation; and opportunities for scholarships and higher education. Health tutors in rural areas generally expressed more frustration with these work conditions than those in urban areas. Conclusions: There is the need to initiate and sustain work incentives that promote motivation of rural health tutors to control ongoing rural-urban migration of qualified staff. It is recommended the following incentives be prioritized to promote retention of qualified health tutors in rural health training schools: payment of research, book and rural allowances; early promotion of rural staff; prioritizing rural tutors for scholarships, and introduction of national best health tutor awards. [ABSTRACT FROM AUTHOR]

Background: Achieving Universal Health Coverage (UHC) by improving financial protection and effective service coverage is target 3.8 of the Sustainable Development Goals. Little is known, however, about the extent to which paying bribes within healthcare acts as a financial barrier to access and, thus, UHC. Methods: Using survey data in adults from 32 sub-Saharan African countries in 2014–2015, we constructed a multilevel model to evaluate the relationship between paying bribes and reported difficulties of obtaining medical care. We controlled for individual-, region-, and country-level variables. Results: Having paid bribes for medical care significantly increased the odds of reporting difficulties in obtaining care by 4.11 (CI: 3.70–4.57) compared to those who never paid bribes, and more than doubled for those who paid bribes often (OR = 9.52; 95% CI: 7.77–11.67). Respondents with higher levels of education and more lived poverty also had increased odds. Those who lived in rural areas or within walking distance to a health clinic had reduced odds of reporting difficulties. Sex, age, living in a capital region, healthcare expenditures per capita, and country Corruption Perception Index were not significant predictors. Conclusions: We found that bribery in healthcare is a significant barrier to healthcare access, negatively affecting the potential of African countries to make progress toward UHC. Future increases in health expenditures—which are needed in many countries to achieve UHC—should be accompanied by greater efforts to fight corruption in order to avoid wasting money. Measuring and tracking health sector-specific corruption is critical for progress toward UHC. [ABSTRACT FROM AUTHOR]

Introduction: Some studies in developing countries have shown that infant mortality is highly associated with maternal education, implying that maternal education might play an important role in the reduction of infant mortality. However, other research has shown that lower levels of maternal education does not have any significant contribution to infant survival. In this systematic review, we focus on the effect of different levels of maternal education on infant mortality in Ethiopia. Methods: MEDLINE, EMBASE, CINAHL, Scopus, and Maternity and Infant Care databases were searched between November 15, 2017 and February 20, 2018. All articles published until February 20, 2018 were included in the study. The data extraction was conducted in accordance with the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA 2009) guidelines. An I2 test was used to assess heterogeneity and a funnel plot was used to check publication bias. Findings: We retrieved 441 records after removing duplications. During screening, 31 articles were fully accessed for data extraction. Finally, five articles were included for analysis. The overall pooled estimate indicated that attending primary education was associated with a 28% reduction in the odds of infant mortality compared to those infants born to mothers who were illiterate, OR: 0.72 (95% CI = 0.66, 0.78). Another pooled estimate indicated that attending secondary education and above was associated with a 45% reduction in the odds of infant mortality compared to those infants born to mothers who were illiterate, OR: 0.55 (95% CI = 0.47, 0.64). Conclusion: From this study, understanding the long-term impact of maternal education may contribute to reduce infant mortality. Therefore, policy makers should give more attention in promoting the role of women through removing institutional and cultural barriers, which hinder women from access to education in order to reduce infant mortality in Ethiopia. [ABSTRACT FROM AUTHOR]

How pervasive is labor market discrimination against immigrants and what options do policymakers and migrants have to reduce it? To answer these questions, we conducted a field experiment on employer discrimination in Sweden. Going beyond existing work, we test for a large range of applicant characteristics using a factorial design. We examine whether migrants can affect their employment chances—by adopting citizenship, acquiring work experience, or signaling religious practice—or whether fixed traits such as country of birth or gender are more consequential. We find little systematic evidence that immigrants can do much to reduce discrimination. Rather, ethnic hierarchies are critical: callback rates decline precipitously with the degree of ethno-cultural distance, leaving Iraqis and Somalis, especially if they are male, with much reduced employment chances. These findings highlight that immigrants have few tools at their disposal to escape ethnic penalties and that efforts to reduce discrimination must address employer prejudice. [ABSTRACT FROM AUTHOR]

Background: Research on contraceptive behaviour changes over time in Uganda is scarce, yet it has among the highest fertility and maternal mortality rates of any country in the East African region. Understanding temporal patterns of contraceptive use for both women and men is vital in evaluating the effectiveness of family planning interventions and strategies, and identifying those with the most unmet need. Using repeated nationally representative cross-sectional samples, this study charts the changes in Uganda’s population-based contraceptive use over recent years. Methods: Five Demographic and Health Survey datasets for Uganda over 21 years, from 1995 to 2016, were sourced and interrogated. Eligible participants included all women aged 15–49 years and men aged 15–54 years. Responses to questions on modern and any (modern or traditional) contraceptive use were analysed. Stratified by gender, weighted regression analyses were employed to detect change over time. The patterns associated with key demographic variables were also investigated. Results: Overall, 50,027 women and 14,092 men were included within the study. In 2016, 30.3% of women and 39.9% of men were using any contraceptive method, a significant non-linear increase from 13.4% of women and 20.3% of men in 1995. Furthermore, 27.3% of women and 35.9% of men were using modern contraceptive methods in 2016, an increase from 7.4% of women and 10.4% of men in 1995. All considered demographic variables were significantly associated with contraceptive use for both women and men (all P<0.001); and for women, all variables differentially changed over time (all P<0.001). Conclusion: This study showed a significant increase and dynamism across key demographic variables in contraceptive uptake by both women and men. Sustained family planning programs and interventions have successfully resulted in behaviour change across the Ugandan population. However, continued efforts are needed to further reduce Uganda’s relatively high fertility and associated maternal mortality rates. [ABSTRACT FROM AUTHOR]

Background: The gap between fertility outcomes and fertility ideals is notably higher in sub-Saharan Africa (SSA) than elsewhere, relating to both under- and overachievement of fertility ideals. We consider the extent to which the relationship between fertility ideals and fertility outcomes is related to educational achievement. Further, we consider if these educational differentials are the same or different in SSA, and thereby consider the extent to which increasing levels of education in SSA may decrease fertility. Data and methods: We use 227 Demographic and Health Surveys (DHSs) from 58 countries worldwide to look at population- level measures of the mismatch between fertility ideals and fertility outcomes. Population level measures are used to assess whether the correspondence between fertility intentions and achievements differ by level of education. We then look at the individual-level determinants of both under- and overachieving fertility intentions. Data from the most recent DHS in 54 of the original countries is used for the individual level analysis, with five countries excluded due to the most recent available survey being out of date. Results: An average of 40% of women in SSA underachieve their stated fertility intentions compared to 26% in non-SSA countries. Furthermore, compared to other LMICs, higher levels of education are not related to better correspondence between fertility intentions and outcomes in SSA. In Middle/Western Africa countries, on average, 48% of women with secondary or higher education have fewer children than their ideal, compared to just 24% who have more children than their ideal. Conclusion: We argue that the phenomenon of underachieving fertility ideals (or unrealized fertility) may be of particular importance for the ongoing fertility transition throughout SSA, especially as more highly educated groups do not appear to be following the patterns observed elsewhere. [ABSTRACT FROM AUTHOR]

Evidence suggests that people with disabilities are the most marginalised and vulnerable group within any population. However, little is known about the extent of inequality between people with and without disabilities in contexts where the majority of persons experience extreme poverty and hardship. This includes in Liberia, where very little is understood about the lives of disabled people in general. This study uses a multidimensional wellbeing framework to understand perceived relative inequality associated with disability by assessing several facets of wellbeing across and within households containing disabled members (N = 485) or households with no disabled members (N = 538) in Liberian communities (Total individuals surveyed, N = 2020). Statistical comparisons (adjusted for age, sex, education and wealth differences and clustered at the household, village and county level) reveal that disabled Liberians are managing similarly to non-disabled Liberians in terms of income and education, but experience many perceived relative inequalities including in life satisfaction, transport access, political participation and social inclusion. Our results further suggest that disability may lead to perceived relative inequality at the household level in terms of trust held in neighbours. However, they also show that being the head of a household may protect against perceived relative inequality in certain dimensions (e.g. healthcare and transport access, political participation) irrespective of disability status. Results are discussed in terms of practical implications for development efforts in Liberia and for disabled people in other low- and middle-income settings. [ABSTRACT FROM AUTHOR]

Poor reproductive health among youth and adolescents threatens their future health and economic wellbeing in Zimbabwe amidst a high HIV/AIDS prevalence. This study evaluates the impact of a multi-pronged adolescent sexual and reproductive health (ASRH) strategy implemented by government of Zimbabwe between 2010 and 2015 to improve ASRH in terms of the uptake of condoms and HIV testing as well as outcomes in terms of sexually transmitted infection (STI) prevalence and HIV prevalence. We combine the difference in difference and propensity score matching methods to analyse repeated Zimbabwe demographic health survey cross-sectional datasets. Young people aged 15–19 years at baseline in 2010, who were exposed for the entire five-year strategy are designated as the treatment group and young adults aged 25–29 at baseline as the control. We find that the ASRH strategy increased HIV testing amongst youth by 36.6 percent, whilst treatment of STIs also increased by 30.4 percent. We also find that the HIV prevalence trajectory was reduced by 0.7 percent. We do not find evidence of impact on condom use and STI prevalence. The findings also suggest that although HIV testing increased for all socio-economic groups that were investigated, the effect was not the same. Lastly, we do not find evidence supporting that more resources translate to better ASRH outcomes. We recommend designing future ASRH strategies in a way that differentiates service delivery for youths in HIV hotspots, rural areas and out of school. We also recommend improving the strategy’s coordination and monitoring, as well as aligning and enforcing government policies that promote sexual and reproductive health rights. [ABSTRACT FROM AUTHOR]

The distribution of silent comic illustrations can facilitate the communication and transfer of scientific recommendations about sustainable land management (SLM) to local communities in countries where many people are illiterate. However, since there are cross-cultural differences in "visual languages", visualization styles need to be carefully selected as well as locals' comprehension of the illustrated recommendation evaluated systematically. Three agricultural recommendations were chosen for comic-style illustrations, distributed to six communities in the Mahafaly region of southwestern Madagascar and evaluated using a three-step, interdependent approach. The silent comics illustrated (i) composting of manure and its application to improve soil fertility; (ii) cautious utilization of succulent silver thicket as supplementary forage; and (iii) sustainable harvesting practices of wild yam. Results revealed that general understandability strongly depended on the community that was surveyed and on the environmental subject that was illustrated. We found a strong relationship between the general understandability of comics and the divergence that exist in communities' socio-economic structure. Education level was an important factor that explained a better understanding of respondents for the comic illustrating compost production, but not for comics that illustrated sustainable usage of silver thicket and wild yam harvest. Willingness to follow the recommended practice was impaired when respondents valued no change to the improved technique compared to the common one. Effects of respondents' socio-economic characteristics on the implementation of the recommended practice could not be clarified within this study due to the small subset of data. Based on the evaluation of recurring comments made by respondents and interviewers, we conclude that comics can be a useful communication tool to increase locals' awareness and comprehension for SLM practices. This, however, requires that drawing details used to facilitate farmers' ability to adopt a point-of-view inside the comic story are used thoughtfully as they might interfere with the central message. [ABSTRACT FROM AUTHOR]

South Africa ranks third among 22 high burden countries in the world. TB which remains a leading cause of death causes one in five adult deaths in South Africa. An in-depth understanding of knowledge, attitudes and practices of young people towards TB is required to implement meaningful interventions. We analysed young men and women (18–24 years)'s TB knowledge including TB/HIV coinfections, testing rates and factors associated with them. A cross sectional cluster-based household survey was conducted in two provinces. Participants completed computer-assisted self-interviews on TB knowledge, testing history and TB/HIV coinfections. A participant was regarded as knowledgeable of TB if s/he correctly answered the WHO-adopted TB knowledge questions. We built three multivariate regression models in Stata 13.0 to assess factors associated with knowing TB alone, testing alone and both knowing and testing for TB. 1955 participants were interviewed (89.9% response rate). Their median age was 20 years (IQR19-22). Sixteen percent (16.2%) of the participants were social grant recipients, 55% were enrolled in a school/college and 5% lived in substandard houses. A total of 72% had knowledge of TB, 21% underwent screening tests for TB and 14.7% knew and tested for TB. Factors associated with TB knowledge were being female, younger, a student, social grant recipient, not transacting sex and having positive attitudes towards people living with HIV (PLWH). Factors associated with TB testing were being a student, receiving a social grant, living in OR Tambo district, HIV knowledge and having a family member with TB history. Factors associated with both TB knowledge and testing were being female, a student, using the print media, living in OR Tambo district and having a family member with a TB history. The study demonstrates the importance of demographic factors (gender, economic status, family TB history, and location) and HIV factors in explaining TB knowledge and testing. We recommend extending community TB testing services to increase testing. [ABSTRACT FROM AUTHOR]

Objective: We assessed feasibility of an HIV-combination-prevention trial among fishing communities in Uganda. Design: Cluster randomised trial in four fishing communities on Lake Victoria, Uganda. Two intervention communities received a combination-prevention-package (behaviour change communication, condom promotion, HIV testing, voluntary male medical circumcision and referral for anti-retroviral therapy if HIV-positive). All four communities received routine government HIV care services. Methods: Using household census data we randomly selected a cohort of consenting residents aged ≥18 years. A baseline sero-survey in July 2014 was followed by two repeat surveys in March and December 2015. We measured uptake of HIV prevention methods, loss-to-follow-up and HIV incidence, accounting for multistage survey design. Results: A total of 862 participants were enrolled and followed for 15 months. Participation was 62% and 74% in the control and intervention arms respectively; Overall loss to follow up (LTFU) was 21.6% and was similar by arm. Self-reported abstinence/faithfulness increased between baseline and endline in both arms from 53% to 73% in the control arm, and 55% to 67% in the intervention arm. Reported condom use throughout the study period was 36% in the intervention arm vs 28% in the control arm; number of male participants reporting circumsicion in both arms from 58% to 79% in the intervention arm, and 39% to 46% in the control arm. Independent baseline predictors of loss-to-follow-up were: being HIV positive, residence in the community for <1 year, younger age, living in an urban area, and being away from the area for >1 month/year Conclusions: Recruitment and retention of participants in longitudinal trials in highly mobile HIV fishing communities is challenging. Future research should investigate modes for locating and retaining participants, and delivery of HIV-combination prevention. [ABSTRACT FROM AUTHOR]

Introduction: Interventions to keep adolescent girls and young women in school, or support their return to school, are hypothesised to also reduce HIV risk. Such interventions are included in the DREAMS combination package of evidence-based interventions. Although there is evidence of reduced risky sexual behaviours, the impact on HIV incidence is unclear. We used nationally representative surveys to investigate the association between being in school and HIV prevalence. Methods: We analysed Demographic and Health Survey data from nine DREAMS countries in sub-Saharan Africa restricted to young women aged 15–19 (n = 20,429 in total). We used logistic regression to assess cross-sectional associations between being in school and HIV status and present odds ratios adjusted for age, socio-economic status, residence, marital status, educational attainment and birth history (aOR). We investigated whether associations seen differed across countries and by age. Results: HIV prevalence (1.0%–9.8%), being currently in school (50.0%-72.6%) and the strength of association between the two, varied between countries. We found strong evidence that being currently in school was associated with a reduced odds of being HIV positive in Lesotho (aOR: 0.37; 95%CI: 0.17–0.79), Swaziland (aOR: 0.32; 95%CI: 0.17–0.59), and Uganda (aOR: 0.48: 95%CI: 0.29–0.80) and no statistically significant evidence for this in Kenya, Malawi, Mozambique, Tanzania, Zambia or Zimbabwe. Conclusions: Although the relationship is not uniform across countries or over time, these data are supportive of the hypothesis that young women in school are at lower risk of being HIV positive than those who leave school in some sub-Saharan African settings. There is a possibility of reverse causality, with pre-existing HIV infection leading to school drop-out. Further investigation of the contextual factors behind this variation will be important in interpreting the results of HIV prevention interventions promoting retention in school. [ABSTRACT FROM AUTHOR]

Schistosomiasis is one of the major Neglected Tropical Diseases (NTDs) in sub-Saharan Africa. In sub-Saharan Africa, two major human schistosome species namely Schistosoma mansoni and S. haematobium often occur sympatrically largely affecting children. Recognizing the public health impact of Schistosomiasis, the World Health Organization (WHO) is urging member states to regularly treat at least 75% and up to 100%, of all school-aged children at risk of morbidity. For control strategies based on targeted mass drug administration (MDA) to succeed it is essential to have a simple and sensitive test for monitoring the success of these interventions. Current available diagnostic tests, such as egg detection in stool by Kato-Katz (KK) for S. mansoni and detection of eggs or blood (hematuria) in urine for S. haematobium have reduced sensitivity in low intensity settings. The objective of the study was to evaluate active single or duo schistosome infections in school children following MDA using molecular diagnostics (PCR) on filtered urine samples and comparing that against traditional diagnostic tests. This cross-sectional study was conducted among 111 school children aged 7–15 years in Chongwe and Siavonga Districts in Zambia. Species-specific cell-free repeat DNA fragment were amplified from 111 filtered urine samples. Our approach detected eight times more positive cases (total 77) than by KK (9) for S. mansoni and six times more (total 72) than by hematuria (11) for S. haematobium and even more against urine filtration (77 compared to only 6). The same pattern was observed when stratified for age group and sex specific analysis with 100% sensitivity and specificity devoid of any cross amplification. In addition, 69 individuals (62%) were co-infected by both parasites. We have demonstrated a significantly higher prevalence of both species than indicated by the traditional tests and the persistent maintenance of reservoir of infection after MDA. Our approach is an effective means of detecting low intensity infection, which will enhance the effectiveness of surveillance and assess the impact of MDA control programs against schistosomiasis. [ABSTRACT FROM AUTHOR]

The Ugandan government is committed to scaling-up proven HIV prevention strategies including safe male circumcision, and innovative strategies are needed to increase circumcision uptake. The aim of this study was to assess the acceptability and feasibility of implementing a soccer-based intervention (“Make The Cut”) among schoolboys in a peri-urban district of Uganda. The intervention was led by trained, recently circumcised “coaches” who facilitated a 60-minute session delivered in schools, including an interactive penalty shoot-out game using metaphors for HIV prevention, sharing of the coaches’ circumcision story, group discussion and ongoing engagement from the coach to facilitate linkage to male circumcision. The study took place in four secondary schools in Entebbe sub-district, Uganda. Acceptability of safe male circumcision was assessed through a cross-sectional quantitative survey. The feasibility of implementing the intervention was assessed by piloting the intervention in one school, modifying it, and implementing the modified version in a second school. Perceptions of the intervention were assessed with in-depth interviews with participants. Of the 210 boys in the cross-sectional survey, 59% reported being circumcised. Findings showed high levels of knowledge and generally favourable perceptions of circumcision. The initial implementation of Make The Cut resulted in 6/58 uncircumcised boys (10.3%) becoming circumcised. Changes made included increasing engagement with parents and improved liaison with schools regarding the timing of the intervention. Following this, uptake improved to 18/69 (26.1%) in the second school. In-depth interviews highlighted the important role of family and peer support and the coach in facilitating the decision to circumcise. This study showed that the modified Make The Cut intervention may be effective to increase uptake of safe male circumcision in this population. However, the intervention is time-intensive, and further work is needed to assess the cost-effectiveness of the intervention conducted at scale. [ABSTRACT FROM AUTHOR]

Background: Understanding the causes of disparities in species diversity across taxonomic groups and regions is a fundamental aim in evolutionary biology. Addressing these questions is difficult because of the need for densely sampled phylogenies and suitable empirical systems. Methodology/Principal Findings: Here we investigate the cichlid fish radiation of Lake Tanganyika and show that per lineage diversification rates have been more than six times slower than in the species flocks of Lakes Victoria and Malawi. The result holds even at peak periods of diversification in Lake Tanganyika, ruling out the age of the lake as an explanation for slow average rates, and is robust to uncertainties over the calibration of cichlid radiations in geological time. Moreover, Lake Tanganyika lineages, irrespective of different biological characteristics (e.g. sexually dichromatic versus sexually monochromatic clades), have diversified at similar rates, falling within typical estimates across a range of plant and animal clades. For example, the mostly sexually dichromatic haplochromines, which have speciated explosively in Lakes Victoria and Malawi, have displayed modest rates in Lake Tanganyika (where they are called Tropheini). Conclusion/Significance: Our results show that either the Lake Tanganyika environment is less conducive for cichlid speciation or the remarkable diversifying abilities of the haplochromines were inhibited by the prior occupancy of older radiations. Although the results indicate a dominant role for the environment in shaping cichlid diversification, differences in the timing of diversification among the Tanganyikan tribes indicate that biological differences were still important for the dynamics of species build-up in the lake. While we cannot resolve the timing of the radiation relative to the origin of the lake, because of the lack of robust geological date calibrations for cichlids, our results are consistent with a scenario that the different clades reflect independent adaptive radiations into different broad niches in the lake. [ABSTRACT FROM AUTHOR]