Search for: All records

Abstract ObjectivesInvestigations of early childhood growth among small‐scale populations are essential for understanding human life history variation and enhancing the ability to serve such communities through global public health initiatives. This study characterizes early childhood growth trajectories and identifies differences in growth patterns relative to international references among Daasanach semi‐nomadic pastoralist children living in a hot, arid region of northern Kenya. MethodsA large sample of height and weight measures were collected from children (N = 1756; total observations = 4508; age = 0–5 years) between 2018 and 2020. Daasanach growth was compared to international reference standards and Daasanach‐specific centile growth curves and pseudo‐velocity models were generated using generalized additive models for location scale and size. ResultsCompared to World Health Organization (WHO) reference, relatively few Daasanach children were stunted (14.3%), while a large proportion were underweight (38.5%) and wasted (53.6%). Additionally, Daasanach children had a distinctive pattern of growth, marked by an increase in linear growth velocity after 24 months of age and relatively high linear growth velocity throughout the rest of early childhood. ConclusionsThese results identify a unique pattern of early childhood growth faltering among children in a small‐scale population and may reflect a thermoregulatory adaptation to their hot, arid environment. As linear growth and weight gain remain important indicators of health, the results of this study provide insight into growth velocity variations. This study has important implications for global public health efforts to identify and address sources of early growth faltering and undernutrition in small‐scale populations. 

Abstract Objective: Water plays a critical role in the production of food and preparation of nutritious meals, yet few studies have examined the relationship between water and food insecurity. The primary objective of this study, therefore, was to examine how experiences of household water insecurity (HWI) relate to experiences of household food insecurity (HFI) among a pastoralist population living in an arid, water-stressed region of northern Kenya. Design: We implemented the twelve-item Household Water Insecurity Experiences (HWISE, range 0–36) Scale and the nine-item Household Food Insecurity Access Scale (HFIAS, range 0–27) in a cross-sectional survey to measure HWI and HFI, respectively. Data on socio-demographic characteristics and intake of meat and dairy in the prior week were collected as covariates of interest. Setting: Northern Kenya, June–July 2019. Participants: Daasanach pastoralist households ( n 136) from seven communities. Results: In the prior 4 weeks, 93·4 % and 98·5 % of households had experienced moderate-to-severe HWI and HFI, respectively. Multiple linear regression analyses indicated a strong association between HWI and HFI. Each point higher HWISE score was associated with a 0·44-point (95 % CI: 0·22, 0·66, P = 0·003) higher HFIAS score adjusting for socio-economic status and other covariates. Conclusions: These findings demonstrate high prevalence and co-occurrence of HWI and HFI among Daasanach pastoralists in northern Kenya. This study highlights the need to address HWI and HFI simultaneously when developing policies and interventions to improve the nutritional well-being of populations whose subsistence is closely tied to water availability and access. 

Fossil cercopithecid primates of the African Plio-Pleistocene are often found together in fossil deposits across East and South Africa. These species may have co-occurred in life and exploited similar types of resources in shared environments, as extant monkeys in Africa and Asia are known to do. Some of these fossil species are represented today by congeneric or descendant species with similar adaptations while others have no modern analogue. This project uses dental morphology to compare community structure across potentially co-occurring fossil and modern cercopithecid populations (the cercopithecid taxocene). Relative enamel thickness, shearing potential, and dental shape ratios from the P4 – M3 toothrow were measured from extant (n > 700) and fossil cercopithecid specimens (n > 1000). The latter primarily targeted the Hadar, Shungura, and Koobi Fora Formations of East Africa and the sites of Makapansgat, Sterkfontein, and Swartkrans in South Africa. Principal component analyses were performed separately on the maxillary and mandibular dentitions and resulting component scores were used to reconstruct the taxocene dental morphology at each site. In general, the African cercopithecid taxocene is similar across the main fossil sites analyzed. Patterns of overlap between fossil and modern sites may reflect environmental similarities or the adaptability of generalist cercopithecids. An apparent niche shift from the Plio-Pleistocene to today reflects both taphonomic and ecological factors: a lack of smaller-bodied fossil cercopithecin and colobine species combined with an expanded dental ecomorphological niche of larger-bodied fossil species. 

This presentation compares methods of estimating brown adipose tissue (BAT). As part of an ongoing study of BAT activity in relation to hot flashes, we asked women aged 45-55 to place their hand in cool (17oC) water. We took a thermal image of each woman (Flir camera) before and after the cooling of her hand. To estimate BAT activity, we compared the change in temperature in the supraclavicular area with a control area. Initially, we used a point on the mid-sternum as the control. Because we were concerned that there may be BAT tissue along the sternum, we also tried a control region on the mid-right arm. We used two equations to estimate BAT activity. The first computed the difference in maximum supraclavicular temperature (SCT) minus the difference in the control temperature [(PostMaxSupraclavicular – PreMaxSupraclavicular) - (PostControlMean - PreControlMean)]. Mean BAT estimated from the maximum SCT and arm temperature was higher (0.80, s.d. 0.51, range 0 to 2.10) than from the maximum SCT and sternal temperature (0.63, s.d. 0.45, range 0 to 1.70). There was no relationship between biceps skinfold and arm temperature, or between other anthropometric measures (summed skinfolds, BMI, percent body fat) and estimates of BAT. The sample size is, to date, too small to draw conclusions (n=36), but as the reported severity of hot flashes increased (“none,” “a little,” “somewhat,” “a lot”) the mean BAT estimated with the sternal control also increased (0.49, 0.65, 0.68, 0.74). This was not true when the arm was used as the control. Support: NSF #BCS-1848330