The prehistoric establishment and expansion of permanent settlements on the Northern Channel Islands of southern California generally follows a pattern predicted by the population ecology model, the ideal free distribution (IFD). We determine this by comparing the abundant archaeological record of these Islands against a careful quantification of habitat suitability using areal photography, satellite imagery, and field studies. We assess watershed area, length of rocky intertidal zone, length of sandy beach for plank canoe pull-outs and area of off-shore kelp beds, for 46 coastal locations. A simple descriptive anal- ysis supports key IFD predictions. A Bayesian model fitted with the Gibbs sampler allows us to recon- struct the Native assessment of habitat that appears to underlie this process. Use of the Gibbs sampler mitigates the impact of missing data, censored variables, and uncertainty in radiocarbon dates; it allows us to predict where new settlements may yet be discovered. Theoretically, our results support a behav- ioral ecology interpretation of settlement history, human population expansion, and economic intensifi- cation in this region. They also demonstrate Bayesian analytical methods capable of making full use of the information available in archaeological datasets.

Agricultural foods and technologies are thought to have eased the mechanical demands of diet-how often or how hard one had to chew-in human populations worldwide. Some evidence suggests correspondingly worldwide changes in skull shape and form across the agricultural transition, although these changes have proved difficult to characterize at a global scale. Here, adapting a quantitative genetics mixed model for complex phenotypes, we quantify the influence of diet on global human skull shape and form. We detect modest directional differences between foragers and farmers. The effects are consistent with softer diets in preindustrial farming groups and are most pronounced and reliably directional when the farming class is limited to dairying populations. Diet effect magnitudes are relatively small, affirming the primary role of neutral evolutionary processes-genetic drift, mutation, and gene flow structured by population history and migrations-in shaping diversity in the human skull. The results also bring an additional perspective to the paradox of why Homo sapiens, particularly agriculturalists, appear to be relatively well suited to efficient (high-leverage) chewing.

When adult males are temporarily away from the household, observational evidence suggests cross-cultural and intra-cultural variation in the effects of their absence on the labor of other household members. In subsistence-based econ- omies, we predict that other adolescent or older members will work more in essential production activities that otherwise would be performed by the missing men. We test this hypoth- esis using spot-check time allocation datasets from rural Nicaragua and Peru and the methodology of mixed-effects statistical models. In Nicaragua, we find that the absence of male household heads rarely necessitates substitute labor by household co-residents, apparently because men typically time their absences to coincide with the non-peak agricultural season. In Peru, the absence of male household heads results in increased men’s work by co-residents only under unusual circumstances, as households apparently rely on other strate- gies to mitigate for the loss of labor. In addition to the com- parative empirical analysis of the two cases, we show how mixed-effects models allow for individual heterogeneity and data structures that confound more familiar statistical techni- ques and occasionally produce spurious results. Mixed-effects modeling techniques will be necessary if we are to realize the analytic potential of the extensive, standardized time al- location datasets gathered by anthropologists.

Conservation strategies to protect biodiversity and support household livelihoods face numerous challenges. Across the tropics, efforts focus on balancing trade-offs in local communities near the borders of protected areas. Devolving rights and control over certain resources to communities is increasingly considered necessary, but decades of attempts have yielded limited success and few lessons on how such interventions could be successful in improving livelihoods. We investigated a key feature of household well-being, the experience of food insecurity, in villages across Tanzania's northern wildlife tourist circuit. Using a sample of 2,499 primarily livestock-keeping households we compared food insecurity in villages participating in the country's principal community-based conservation strategy with nearby control areas. We tested whether community-based projects could offset the central costs experienced by households near strictly protected areas (i.e. frequent human-wildlife conflict and restricted access to resources). We found substantial heterogeneity in outcomes associated with the presence of community-based conservation projects across multiple project sites. Although households in project villages experienced more frequent conflict with wildlife and received few provisioned benefits, there is evidence that these households may have been buffered to some degree against negative effects of wildlife conflict. We interpret our results in light of qualitative institutional factors that may explain various project outcomes. Tanzania, like many areas of conservation importance, contains threatened biodiversity alongside areas of extreme poverty. Our analyses highlight the need to examine more precisely the complex and locally specific mechanisms by which interventions do or do not benefit wildlife and local communities.

Introduction

Concentrations of the total pool of fibronectin in plasma (TFN), and the subset of this pool that contains the alternatively spliced EDA segment (A(+)FN), are both affected by disease processes, and the latter pool has gained a reputation as a biomarker for vascular injury. We therefore wished to determine if changes in either FN pool correlate with clinical outcomes in critically ill individuals.

Methods

We analyzed a database for 57 patients with major trauma (n = 33) or sepsis syndrome (n = 24) in which plasma levels of TFN and A(+)FN had been measured at intervals, along with clinical parameters. Logistic regression analysis was performed to detect associations between predictive variables and three clinical outcomes: 1) the acute respiratory distress syndrome (ARDS), 2) milder acute lung injury designated acute hypoxemic respiratory failure (AHRF), and 3) survival to hospital discharge.

Results

An increase in plasma TFN during the first 24 hours of intensive care unit (ICU) observation was negatively associated with progression to ARDS (odds ratio 0.98 per 1 microgram (μg)/ml increase, 95% CI (0.97, 1.00)) and AHRF (OR 0.97 per 1 μg/ml increase, (0.95, 0.99)), whereas an increase in A(+)FN over the first 24 hours was positively associated with progression to AHRF (OR 1.65 per 1 μg/ml increase, (1.04, 2.62)). Additionally, the ratio of the partial pressure of oxygen in arterial blood (PaO(2)) to the percentage of oxygen in inspired air (FIO(2)) after 24 hours was positively associated with survival (OR 1.01 per 1 unit increase in ratio, (1.00, 1.03)), along with change in A(+)FN (OR 1.30 per 1 μg/ml increase, (0.90, 1.88)).

Conclusions

Different FN isoforms may constitute predictive covariate markers for distinct clinical outcomes in critically ill patients. The data also suggest that early TFN accumulation in the circulation may confer a clinical benefit to patients at risk for acute lung injury.

Using a sample of 40 sources reporting milpa and mucuna-intercropped maize yields in Mesoamerica, we test Boserup’s (1965) prediction that fallow is reduced as a result of growing population density. We further examine direct and indirect effects of population density on yield. We find only mixed support for Boserupian intensification. Fallow periods decrease slightly with increasing population density in this sample, but the relationship is weak. Controlling for other covariates, fallow-unadjusted maize yields first rise then fall with population density. Fallow-adjusted maize yields peak at 390 kg/ha/yr for low population densities (8 persons / km2) and decline to around 280 kg/ha/yr for the highest population densities observed in our dataset. Fallow practices do not appear to mediate the relationship between population density and yield. The multi-level modeling methods we adopt allow for data clustering, accurate estimates of group-level variation, and they generate conditional predictions, all features essential to the comparative study of prehistoric and contemporary agricultural yields.

A Minor Role for Environmental Adaptation in Local–Scale Maize Landrace Distribution: Results from a Common Garden Experiment in Oaxaca, Mexico. Agronomists usually assume that yield is a primary selection trait for farmers practicing traditional agriculture. They hypothesize that the landraces grown in farmers’ fields produce higher yields than other local landraces would, if grown in the same fields. We test this hypothesis in experimental gardens using maize landraces grown by indigenous farmers in a low– to mid–elevation region in Oaxaca, Mexico. We selected four villages, two Chatino and two Mixtec, two in low and two in middle elevations. We planted reciprocal common gardens in each village, in order to test whether or not local maize landraces were higher yielding in their respective villages—a finding that would suggest they are selected because they are better adapted to local conditions than landraces from other villages. We also tested resistance to a fungal disease (ear rot caused by Fusarium) that is cited by farmers in the region as a major problem for maize production. We found that maize samples planted in their villages of origin did not in general have higher yields than samples from other villages. There are significant interactions among common garden site, fertilizer use, and seed source. We found that landraces from the Chatino lowlands village perform well in most sites, with and without fertilizer. Regarding ear rot, there is some evidence that landraces are less susceptible when grown away from their villages of origin. These results suggest that social factors, such as seed networks and ethno–linguistic membership, may be more important than local environmental adaptation in determining the distribution of landraces in this region.

The reduced emissions in deforestation and degradation (REDD+) initiative uses payments for ecosystem services as incentives for developing countries to manage and protect their forests. REDD+ initiatives also prioritize social (and environmental) co-benefits aimed at improving the livelihoods of communities that are dependent on forests. Despite the incorporation of co-benefits into REDD+ goals, carbon sequestration remains the primary metric for which countries can receive payments from REDD+, but after more than 10 years of REDD+, many site-specific programs have failed to complete the carbon verification process. Here, we examine whether the REDD+ social co-benefits alone are sufficient to have slowed deforestation in the absence of carbon payments on Pemba, Tanzania. Using satellite imagery (Landsat archive), we quantified forest cover change for the period before (2001-2010) and after (2010-2018) the launch in 2010-2011 of Pemba island's REDD+ readiness project. We then compared rates of forest cover change between shehia (administrative units) that were part of REDD+ readiness intervention and those that were not, adjusting for confounding variables and the non-random selection of REDD+ shehia with a statistical matching procedure. Despite considerable variation in forest outcomes among shehia, the associated co-benefits with the Pemba REDD+ project had no discernible effect on forest cover change. Likewise, we did not detect an effect of socioecological covariates on forest cover change across all shehia, though island-wide human population growth since 2012 may have played a role. These findings are unsurprising given the failure to secure carbon payments on Pemba and indicate that co-benefits alone are insufficient to reduce deforestation. We conclude that better oversight of all-involved parties is needed to ensure that REDD+ interventions satisfactorily conclude the process of securing a mechanism for carbon payments, if slowing deforestation is to be achieved.

Use-wear analysis provides a means of studying traces produced on animal bone during manufacture and use in an effort to reconstruct these processes. Often, these analyses are qualitative and based on experience and expertise. Previous studies have focused on interpreting final traces, but little is known about how these traces develop and change over time. We propose the use of an innovative quantitative method for studying bone surface traces that aims to reduce any unreliable or non-replicable results that can confound more traditional qualitative analyses. We seek to understand the basics of use-wear formation over Time by taking incremental molds of bone specimens subjected to a controlled, mechanical experiment. This study assesses how bone wears during extended use on three Material types (fresh skin, processed leather, or dry bark), from three initial Manufacturing states (unworked, ground with sandstone, or scraped with flint). With data obtained from a confocal disc-scanning microscope, we then apply 3D surface texture analysis using ISO 25178 parameters: surface roughness [Sa], autocorrelation length [Sal], peak curvature [Spc], and upper material ratio [Smr1]. We employ a multilevel multivariate Bayesian model to explain parameter variation under experimental conditions. Our findings show how duration of use strongly affects the transformation of the bone's surface. Unworked bone is completely distinguishable from bone used for long time intervals and those modified by scraping. Interestingly, material wear does not often produce type-specific traces, but does affect the rate of bone alteration and how it is transformed. Specifically, fresh skin transforms bone at a faster rate than other materials. This novel quantitative and experimental approach enhances our understanding of the use of bone as a raw material for making and using tools and provides a foundation for future exploration of archaeological materials and questions.