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Terrestrial animals feed on fruit dropped by arboreal frugivores in tropical forests around the world, but it remains unknown whether the resulting spatial associations of these animals are coincidental or intentionally maintained. On Barro Colorado Island, Panama, we used a combination of acoustic playback experiments, remote camera monitoring, and GPS tracking to quantify the frequency of such interactions, determine who initiates and maintains spatial associations, and test whether terrestrial animals adopt a strategy of acoustic eavesdropping to locate fruit patches created by foraging primates. Indeed, 90% of fruits collected in fruit fall traps had tooth marks of arboreal frugivores, and terrestrial frugivores visited fruit trees sooner following visits by GPS-collared monkeys. While our play back experiments were insufficient to support the hypothesis that terrestrial frugivores use auditory cues to locate food dropped by arboreal primates, analyses of movement paths of capuchin monkeys (Cebus capucinus), spider monkeys (Ateles geoffroyi), and coatis (Nasua narica) reveal that observed patterns of interspecific attraction are not merely a byproduct of mutual attraction to shared resources. Coatis were significantly more likely to initiate close encounters with arboreal primates than vice versa and maintained these associations by spending significantly longer periods at fruiting trees when collared primates were present. Our results demonstrate that terrestrial frugivores are attracted to arboreal primates, likely because they increase local resource availability. Primates are often among the first species in a habitat to be extirpated by hunting; our results suggest that their loss may have unanticipated consequences for the frugivore community. Abstract in Spanish is available with online material.

Background Impaired nutritional status has been linked to cardiovascular diseases. Both selenium and iron deficiency have been associated with impaired exercise tolerance and worse prognosis in patients with heart failure (HF) as well as mitochondrial dysfunction in human cardiomyocytes. With exception of magnesium, little is known about the role of micronutrients in the development of atrial fibrillation (AFib). Purpose To elucidate the association of micronutrient deficiencies with new-onset AFib. Methods Selenium, magnesium and iron parameters were measured in a well-characterized Dutch prospective cohort study (N=5452). Selenium deficiency was defined as selenium Results The mean age was 53.3 (12.0) years and 2843 (52.1%) of all participants were women. During a mean follow-up of 6.2 years, 136 (2.5%) participants developed new-onset AFib. Of the participants who developed AFib, 25.7% had selenium deficiency, 5.1% had iron deficiency, and 75% had magnesium deficiency, compared to 21.1%, 14.9% and 65.8% of those who did not develop AFib, respectively. Smoking status significantly interacted with selenium deficiency on outcome (p=0.075). After multivariable adjustment for components of the CHARGE-AF model, selenium deficiency was associated with new-onset AFib in non-smokers (HR: 1.69, 95% CI: 1.08 to 2.66, p=0.022), but not in smokers (HR: 0.71, 95% CI: 0.27 to 1.90, p=0.494). There was no significant association between the new-onset AFib and magnesium deficiency (HR: 1.40, 95% CI: 0.93 to 2.12, p=0.108) or iron deficiency (HR: 0.59, 95% CI: 0.23–1.49, P=0.266). Participants with two or more deficiencies had higher risk to develop AFib compared to those without deficiencies (HR: 1.75, 95% CI: 1.00 to 3.06, p=0.050). Conclusion In a community-based cohort, selenium deficiency was associated with new-onset AFib in non-smoking participants. Interventional studies that investigate the effects of optimizing micronutrients status in a population at risk are needed to assess causality, especially in those with selenium deficiency. Funding Acknowledgement Type of funding sources: Other. Main funding source(s): ENW-KLEIN grantthe Junior Scientific Masterclass-MD/PhD program of the UMCG

Funding Acknowledgements Type of funding sources: Public grant(s) – National budget only. Main funding source(s): A grant of the Dutch Kidney Foundation (E0.13)Dutch Research Council (NWO) Open Competition ENW-M grant (OCENW.KLEIN.483) Background Recent studies suggest a link between nutritional status and new-onset atrial fibrillation (AF). Both selenium deficiency (SeD) and iron deficiency (ID) are known to impair mitochondrial function in human cardiomyocytes and both have been associated with worse prognosis in patients with cardiovascular disease. However, little is known about the role of these micronutrients in the development of AF. Purpose To elucidate the association of SeD and ID with new-onset AF in the general population. Methods Selenium and iron parameters were measured in a well-characterized Dutch prospective cohort study (N = 5591) with a mean follow-up of 6.2 years. SeD was defined as selenium concentrations < 70ug/L, and ID as ferritin concentrations Results In the PREVEND cohort, mean age was 53.5 (±12) years and 2917 subjects (52%) were females. SeD and ID were observed in 1212 (21%) and 891 (15%) subjects, respectively. Both deficiencies had similar associates, including sex, BMI, smoking status, cholesterol levels and anemia. Of the subjects who developed AF, 25% had SeD and 5% had ID. There was a significant interaction between SeD and smoking in association with the outcome (P= 0.084). After adjusting for the validated CHARGE-AF model in the addition of potential confounders, SeD was independently associated with new onset AF in nonsmokers (Hazard Ratio (HR): 1.72, 95% Confidence Interval (CI): 1.07 to 2.76, P = 0.024), but not in smokers (HR: 0.81, 95% CI: 0.32 to 2.05, P = 0.658). ID, however, was not associated with new-onset AF (HR: 0.62, 95% CI: 0.26 to 1.46, P = 0.272), regardless of sex stratification or smoking status. Conclusion In a general population cohort, SeD was independently associated with new-onset AF in nonsmokers. No association was found between ID and AF. Interventional studies that investigate the effects of selenium supplementation in a population at risk are needed.

Aims: Whereas the combination of anaemia and chronic kidney disease (CKD) has been extensively studied in patients with heart failure (HF), the contribution of iron deficiency (ID) to this dysfunctional interplay is unknown. We aimed to assess clinical associates and pathophysiological pathways related to ID in this multimorbid syndrome.Methods and results: We studied 2151 patients with HF from the BIOSTAT-CHF cohort. Patients were stratified based on ID (transferrin saturation 2). Patients were mainly men (73.3%), with a median age of 70.5 (interquartile range 61.4–78.1). ID was more prevalent than CKD and anaemia (63.3%, 47.2% and 35.6% respectively), with highest prevalence in those with concomitant CKD and anaemia (77.5% vs. 59.3%; p < 0.001). There was a considerable overlap in biomarkers and pathways between patients with isolated ID, anaemia or CKD, or in combination, with processes related to immunity, inflammation, cell survival and cancer amongst the common pathways. Key biomarkers shared between syndromes with ID included transferrin receptor, interleukin-6, fibroblast growth factor-23, and bone morphogenetic protein 6. Having ID, either alone or on top of anaemia and/or CKD, was associated with a lower overall summary Kansas City Cardiomyopathy Questionnaire score, an impaired 6-min walk test and increased incidence of hospitalizations and/or mortality in multivariable analyses (all p < 0.05).Conclusion: Iron deficiency, CKD and/or anaemia in patients with HF have great overlap in biomarker profiles, suggesting common pathways associated with these syndromes. ID either alone or on top of CKD and anaemia is associated with worse quality of life, exercise capacity and prognosis of patients with worsening HF.

Does resource extraction during experimental economic games reflect resource use and behavior in other contexts? This question about external validity is central to determining the inferences that can be drawn from experimental evidence to broader sets of circumstances. Building on previous studies of external validity, which often raise concerns about the generalizability of experimental economic games to other contexts, we instead highlight parallelism between behavior inside and outside of games and its implications for applied research. Here we present the results from a framed multiphase common-pool resource game played with fishermen from a fishing community in Baja California Sur to explore the associations between game play and both self-reported and observed behavioral measures. Participants played an experimental economic game that incorporated both fisheries-specific resource dynamics and the current policy context of local fisheries management. Game administration followed two years of interviews, participant observation, and household surveys in the community. In addition to providing an in-depth understanding of the broader social-ecological context, this allowed us to compare similar game, self-reported, and observed behaviors for the same individuals. Overall, we found little evidence for external validity in terms of parallelism. None of the tests for association between fishing behaviors in the game and survey met the study-wide significance threshold. Only one association—between game behavior and conservation values—was significant at the single-test level. Based on our results, we caution against relying solely on experimental economic games as proxies for behaviors regarding resource use when developing policies. Collecting multiple or iterative measures of behavior using mixed methods is a necessary precaution, especially if the goal is to make specific policy recommendations.

The Snake Detection Theory implicates constricting snakes in the origin of primates, and venomous snakes for differences between catarrhine and platyrrhine primate visual systems. Although many studies using different methods have found very rapid snake detection in catarrhines, including humans, to date no studies have examined how quickly platyrrhine primates can detect snakes. We therefore tested in captive coppery titi monkeys (Plecturocebus cupreus) the latency to detect a small portion of visible snake skin. Because titi monkeys are neophobic, we designed a crossover experiment to compare their latency to look and their duration of looking at a snake skin and synthetic feather of two lengths (2.5 cm and uncovered). To test our predictions that the latency to look would be shorter and the duration of looking would be longer for the snake skin, we used survival/event time models for latency to look and negative binomial mixed models for duration of looking. While titi monkeys looked more quickly and for longer at both the snake skin and feather compared to a control, they also looked more quickly and for longer at larger compared to smaller stimuli. This suggests titi monkeys’ neophobia may augment their visual abilities to help them avoid dangerous stimuli.

International audience; Five nearly identical fragments of specialized bone tools, interpreted as lissoirs (French for "smoothers"), have been found at two Middle Paleolithic sites in southwest France. The finds span three separate archaeological deposits, suggesting continuity in the behavior of late Neandertals. Using standard morphological assessments, we determined that the lissoirs were produced on ribs of medium-sized ungulates. However, since these bones are highly fragmented and anthropogenically modified, species determinations were challenging. Also, conservative curation policy recommends minimizing destructive sampling of rare, fragile, or small artifacts for molecular identification methods. To better understand raw material selection for these five lissoirs, we reassess their taxonomy using a non-destructive ZooMS methodology based on triboelectric capture of collagen. We sampled four storage containers and obtained identifiable MALDI-TOF MS collagen fingerprints, all indicative of the same taxonomic clade, which includes aurochs and bison (Bos sp. and Bison sp.). The fifth specimen, which was stored in a plastic bag, provided no useful MALDI-TOF MS spectra. We show that the choice of large bovid ribs in an archaeological layer dominated by reindeer (Rangifer tarandus) demonstrates strategic selection by these Neandertals. Furthermore, our results highlight the value of a promising technique for the non-destructive analysis of bone artifacts.

Selective logging in tropical rain forests may promote population growth of invasive plants. The ability of invaders to respond, specifically in reproductive traits, to increase in resource abundance may allow them to increase their presence in the seed rain of recipient communities. The invasive pioneer tree Bellucia pentamera (Melastomataceae) is currently spreading within Gunung Palung National Park in West Kalimantan, Indonesia. The park has also experienced periods of illegal, small‐scale, selective logging that seem to have facilitated population growth and spread of this invader. We first used fruiting frequency as a proxy for fruit output to make comparisons between B. pentamera and the native tree community of over 200 genera. We then constructed two Generalized Linear Autoregressive Moving Average (GLARMA) models using 13 months of phenology data to predict both fruiting frequency and crop size of B. pentamera under selective logging versus natural treefall disturbance regimes. Bellucia pentamera fruited at considerably higher frequency than all 200 native genera considered. This invader also responded positively to selective logging with both odds of being in fruit and crop sizes at least doubling in logged plots. Prolific seed output of B. pentamera is especially problematic within the lottery competition of tropical rain forest gap tree communities, in which prominence in the seed rain is particularly important. Furthermore, the reproductive response of B. pentamera to selective logging suggests that this harvesting practice may have a considerable role in facilitating this invasion in Southeast Asia.

Discussions of heat treatment in the southern African Middle Stone Age often focus on the importance of this innovation to the development of complex technologies and the evolution of modern human cognition. Debates regarding the context of silcrete heat treatment typically include the amount of time and resource investment needed, and when the earliest occurrences of heat treatment appear in the archaeological record. However, silcrete is a heterogeneous material and the potential effects of this heterogeneity on the thermal transformations that occur during heat treatment are not well established. We undertook a series of controlled experiments using direct transmission near-infrared spectroscopy on South African silcretes from multiple sources heated to a range of maximum temperatures to examine the degree of heterogeneity in starting structural content and the evolution of thermal transformations. We found that material source is an important determinant of starting concentrations of H2O, SiOH, and pore space in silcrete, as well as the thermal evolution of these variables. These results shed light on the degree and sources of variation in the structural content and thermal behavior of silcrete during heat treatment and allow for a better understanding of the heterogeneity of silcrete as a raw material and the implications of this for African Middle Stone Age pyrotechnology.

Saki monkeys (Pithecia spp.) live in pairs and small groups, sometimes with more than 1 same-sex adult. Previous studies have not been able to distinguish additional, unrelated adults from adult-sized offspring, but both can influence social relationships and mating strategies, albeit in different ways. In this study, we documented the immigration of an adult male equatorial saki (P. aequatorialis) into a group following the departure of the previous resident male. At immigration, the group contained an adult female, her 5-year-old (adult age) and 1.5-year-old daughters, and her 1-month-old infant. We used nearest neighbor, approach, grooming, playing, aggression, and copulation data to describe the social dynamics between the immigrant male and the 2 adult females. In the 12 months following his arrival, the immigrant male tended to be closer to and groom the adult daughter more than the mother, but he mated with both females. Both females interacted more with the immigrant male than with each other, and both females eventually reproduced. These observations provide evidence that in equatorial sakis, adult offspring may delay dispersal and reproduce within their natal group, thus transitioning from groups of reproductive pairs to groups with more than 1 reproductive adult of the same sex.

An arboreal lifestyle is thought to be central to primate origins, and most extant primate species still live in the trees. Nonetheless, terrestrial locomotion is a widespread adaptation that has arisen repeatedly within the primate lineage. The absence of terrestriality among the New World monkeys (Platyrrhini) is thus notable and raises questions about the ecological pressures that constrain the expansion of platyrrhines into terrestrial niches. Here, we report the results of a natural experiment, comparing patterns of terrestrial behavior in white-faced capuchin monkeys (Cebus capucinus imitator) living on two islands off the Pacific coast of Panama that lack mammalian predators (island sites) with the behavior of capuchins at three sites in central Panama with more intact predator communities (mainland sites). Surveys with camera traps revealed increased terrestriality in island vs. mainland sites. Capuchin detection rates were higher, the range of party sizes observed was larger, and individuals engaged in a wider range of terrestrial behaviors on the islands lacking mammalian predators. Furthermore, females carrying infants were frequently photographed on the ground at the island sites, but never at the mainland sites. These findings support the long-standing hypothesis that predators constrain the exploitation of terrestrial niches by primates. These results are also consistent with the hypothesis that arboreal locomotion imposes costs that primates will avoid by walking on the ground when predation risk is low. published

Groundwater quality is a concern in alluvial aquifers that underlie agricultural areas, such as in the San Joaquin Valley of California. Shallow domestic wells (less than 150 m deep) in agricultural areas are often contaminated by nitrate. Agricultural and rural nitrate sources include dairy manure, synthetic fertilizers, and septic waste. Knowledge of the relative proportion that each of these sources contributes to nitrate concentration in individual wells can aid future regulatory and land management decisions. We show that nitrogen and oxygen isotopes of nitrate, boron isotopes, and iodine concentrations are a useful, novel combination of groundwater tracers to differentiate between manure, fertilizers, septic waste, and natural sources of nitrate. Furthermore, in this work, we develop a new Bayesian mixing model in which these isotopic and elemental tracers were used to estimate the probability distribution of the fractional contributions of manure, fertilizers, septic waste, and natural sources to the nitrate concentration found in an individual well. The approach was applied to 56 nitrate-impacted private domestic wells located in the San Joaquin Valley. Model analysis found that some domestic wells were clearly dominated by the manure source and suggests evidence for majority contributions from either the septic or fertilizer source for other wells. But, predictions of fractional contributions for septic and fertilizer sources were often of similar magnitude, perhaps because modeled uncertainty about the fraction of each was large. For validation of the Bayesian model, fractional estimates were compared to surrounding land use and estimated source contributions were broadly consistent with nearby land use types.

The theoretical basis for understanding how human forager mobility should respond to environmental change rests on two models: patch choice and the marginal value theorem. Students of hunter–gatherers have traditionally understood the more widely favored marginal value theorem to predict that use of a given patch will be more intensive, i.e., that a greater fraction of its resources will be used, when overall (environmental) return rate decreases. We show this is true only if that patch is less affected by resource decrease than others in the environment, in the simplest case, where the number of patches available to a forager decreases without affecting the quality of the remaining patches. Then, foraging time within the patch, fraction of patch resources used, and travel time between patches will all increase. Conversely, if resources decrease across all patches uniformly, the fraction of patch resources extracted from any given patch remains constant. Within-patch foraging time may or may not decrease, but will not increase. In this case, foraging time varies independently of fraction of patch resources used and travel time. The extent to which these marginal value predictions account for hunter–gatherer mobility requires disentangling them from predictions independently generated by the patch choice model, in which as environmental quality declines, lower ranking patches are added to the foraging itinerary, decreasing travel time and either increasing or decreasing foraging time, depending on the nature of the lower ranking patches. A sample of 190 mobile hunter–gatherers suggests that a version of the patch choice model in which the patches added to the foraging itinerary are more difficult to search, and contain greater quantities of resources with higher handling times, best accounts for observed variation in foraging and travel time overall.

International audience; "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." (source éditeur)

Acoustic signals serve important functions in mate choice, resource defense, and species recognition. Quantifying patterns and sources of variation in acoustic signals can advance understanding of the evolutionary processes that shape behavioral diversity more broadly. Animal vocalization datasets are inherently multivariate and hierarchical, wherein multiple features are estimated from calls of many individuals across different recording locations. Patterns of variation within different hierarchical levels-notwithstanding the challenges they present for modeling and inference-can provide insight into processes shaping vocal variation. The current work presents a multivariate, variance components model to investigate three levels of variance (within-female, between-female, and between-site) in Bornean gibbon calls. For six of the eight features estimated from call spectrograms, between-female variance was the most important contributor to total variance. For one feature, trill rate, there were site-level differences, which may be related to geographic isolation of certain gibbon populations. There was also a negative relationship between trill rate and duration of the introduction, suggesting trade-offs in the production of gibbon calls. Given substantial inter-individual variation in gibbon calls, it seems likely that there has been selection to confer information regarding caller identity, but mechanisms leading to site-level variation in trill rate remain to be determined.

While the vast majority of genome size variation in plants is due to differences in repetitive sequence, we know little about how selection acts on repeat content in natural populations. Here we investigate parallel changes in intraspecific genome size and repeat content of domesticated maize (Zea mays) landraces and their wild relative teosinte across altitudinal gradients in Mesoamerica and South America. We combine genotyping, low coverage whole-genome sequence data, and flow cytometry to test for evidence of selection on genome size and individual repeat abundance. We find that population structure alone cannot explain the observed variation, implying that clinal patterns of genome size are maintained by natural selection. Our modeling additionally provides evidence of selection on individual heterochromatic knob repeats, likely due to their large individual contribution to genome size. To better understand the phenotypes driving selection on genome size, we conducted a growth chamber experiment using a population of highland teosinte exhibiting extensive variation in genome size. We find weak support for a positive correlation between genome size and cell size, but stronger support for a negative correlation between genome size and the rate of cell production. Reanalyzing published data of cell counts in maize shoot apical meristems, we then identify a negative correlation between cell production rate and flowering time. Together, our data suggest a model in which variation in genome size is driven by natural selection on flowering time across altitudinal clines, connecting intraspecific variation in repetitive sequence to important differences in adaptive phenotypes., Author summary Genome size in plants can vary by orders of magnitude, but this variation has long been considered to be of little functional consequence. Studying three independent adaptations to high altitude in Zea mays, we find that genome size experiences parallel pressures from natural selection, causing a reduction in genome size with increasing altitude. Though reductions in overall repetitive content are responsible for the genome size change, we find that only those individual loci contributing most to the variation in genome size are individually targeted by selection. To identify the phenotype influenced by genome size, we study how variation in genome size within a single wild population impacts leaf growth and cell division. We find that genome size variation correlates negatively with the rate of cell division, suggesting that individuals with larger genomes require longer to complete a mitotic cycle. Finally, we reanalyze data from maize inbreds to show that faster cell division is correlated with earlier flowering, connecting observed variation in genome size to an important adaptive phenotype.

We introduce a hybrid integration platform based on the combination of passive and electro-optic polymers. We analyze the optical and physical compatibility of these materials and describe the advantages that our hybrid platform is expected to have for the development of transmitters in terms of operation flexibility and speed. We combine our platform with InP electronics and develop a transmitter with 22-nm tunability in the C-band and potential for serial non-return-to-zero on-off-keying operation directly at 100 Gb/s. We investigate its transmission performance at 80 and 100 Gb/s using dispersion uncompensated standard single-mode fiber and demonstrate bit-error rate (BER) lower than 10(-10) at 80 Gb/s after 1625 m, lower than 10(-10) at 100 Gb/s after 500 m, lower than 10(-9) at 100 Gb/s after 1000 m, and BER 10(-7) at the same rate after 1625 m. We also employ the transmitter inside an experimental setup, which aims to emulate an optical circuit switched (OCS) domain of an intradata center network, and demonstrate at 100 Gb/s the way, in which its wavelength tunability can resolve contentions and improve the flexibility and the efficiency of the network. Finally, we outline our next plans, including the development of flexible and ultra-fast transmitters for coherent systems using the same polymer-to-polymer integration platform.

Objectives We expand upon a multivariate mixed model from quantitative genetics in order to estimate the magnitude of climate effects in a global sample of recent human crania. In humans, genetic distances are correlated with distances based on cranial form, suggesting that population structure influences both genetic and quantitative trait variation. Studies controlling for this structure have demonstrated significant underlying associations of cranial distances with ecological distances derived from climate variables. However, to assess the biological importance of an ecological predictor, estimates of effect size and uncertainty in the original units of measurement are clearly preferable to significance claims based on units of distance. Unfortunately, the magnitudes of ecological effects are difficult to obtain with distance-based methods, while models that produce estimates of effect size generally do not scale to high-dimensional data like cranial shape and form. Methods Using recent innovations that extend quantitative genetics mixed models to highly multivariate observations, we estimate morphological effects associated with a climate predictor for a subset of the Howells craniometric dataset. Results Several measurements, particularly those associated with cranial vault breadth, show a substantial linear association with climate, and the multivariate model incorporating a climate predictor is preferred in model comparison. Conclusions Previous studies demonstrated the existence of a relationship between climate and cranial form. The mixed model quantifies this relationship concretely. Evolutionary questions that require population structure and phylogeny to be disentangled from potential drivers of selection may be particularly well addressed by mixed models. Am J Phys Anthropol, 2015. © 2015 Wiley Periodicals, Inc.

Uncertainty about fitness-enhancing traits in a potential mate, as well as variability in social and ecological environments, favors the use of multiple cues in selecting a partner. Though how individuals respond with adaptive mating preferences is an open question. Here we investigate mate choice decision making among the Makushi of Guyana and compare two competing approaches: 1) a prioritized trait approach, in which preferences are determined by the independent evaluation of relevant partner traits; and 2) an integrative approach, in which preferences are determined by reducing multiple, interrelated traits to a few latent dimensions. Within these two approaches we measure the effects of several key factors — sex, adult sex ratio, and community-to-community variability — thought to pattern preferences. We find support for cue integration and contextual variability in preferences. Sex and adult sex ratio are weak predictors of preferences in the Makushi: preferences are best explained by unstructured community effects. These findings highlight two key issues in mate choice studies: 1) simple biologically-based models do not seem adequate to explain variation in preferences, either within or among populations; and 2) while context, generally speaking, matters in determining preferences, we lack theoretically-informed predictions about relevant contextual factors. The importance of cues, as well as what they signal in a potential partner, is likely to vary with location-specific factors that are yet unexplored.

Author(s): Salerno, J; Borgerhoff Mulder, M; Grote, MN; Ghiselli, M; Packer, C | Abstract: 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.

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.

Female mammals often begin to reproduce before achieving somatic maturity and therefore face tradeoffs between allocating energy to reproduction or their own continued development. Constraints on primiparous females are associated with greater reproductive failure, and first-born infants often have slower growth and greater mortality and morbidity than infants born to multiparous females. Effects of early life investment may persist even after weaning when juveniles are no longer dependent on maternal care and mother's milk. We investigated the long-term consequences of birth order in a large sample of rhesus macaques, Macaca mulatta, assigned to the outdoor breeding colony at the California National Primate Research Center (n = 2,724). A joint model for growth and mortality over the first three years of life allowed us to explicitly connect growth rates to survival. As expected, males are born heavier and grow faster relative to females. However, contrary to expectations, later-born males face substantially lower survival probability during their first three years, whereas first-born males survive at greater rates similar to both first-born and later-born females. Primiparous mothers are less likely to conceive during the subsequent breeding season, suggesting that their reproductive costs are greater than those of multiparous mothers. We speculate that compensatory tactics, both behavioral and physiological, of first-born offspring and their mothers, as well as the novel ecology of the captive environment, underlie these findings. The results presented here provide new insights into how maternal and infant life history tradeoffs may influence developmental trajectories even after the period of maternal dependence. Am. J. Primatol. 77:963-973, 2015. © 2015 Wiley Periodicals, Inc.

Saki monkeys live in socially monogamous groups and in groups containing more than one same-sex adult. As part of a 10-year study of equatorial sakis (Pithecia aequatorialis) in Ecuador, we documented the immigration of a second adult male into a group containing a resident male-female pair that had associated with one another for seven years and the resident female's two daughters. In the first month after immigration, the resident male spent more time closer to and grooming his putative adult daughter than the resident female, and the two males were seen performing a cooperative territorial display. After two months, the resident male interacted more with the resident female than with his putative adult daughter, while that daughter interacted more with the immigrant male and copulated with him. After three months, the males left the group together and associated with an unfamiliar female, leaving the resident females and a neonate behind. The resident male then paired with a new female, while the immigrant male joined another group, again as a second male. Compared to other socially monogamous primates, sakis appear to have a more variable social system whereby additional males can join established groups and form relationships with putatively unrelated males.

Acoustic signals serve important functions in mate choice, resource defense, and species recognition. Quantifying patterns and sources of variation in acoustic signals can advance understanding of the evolutionary processes that shape behavioral diversity more broadly. Animal vocalization datasets are inherently multivariate and hierarchical, wherein multiple features are estimated from calls of many individuals across different recording locations. Patterns of variation within different hierarchical levels-notwithstanding the challenges they present for modeling and inference-can provide insight into processes shaping vocal variation. The current work presents a multivariate, variance components model to investigate three levels of variance (within-female, between-female, and between-site) in Bornean gibbon calls. For six of the eight features estimated from call spectrograms, between-female variance was the most important contributor to total variance. For one feature, trill rate, there were site-level differences, which may be related to geographic isolation of certain gibbon populations. There was also a negative relationship between trill rate and duration of the introduction, suggesting trade-offs in the production of gibbon calls. Given substantial inter-individual variation in gibbon calls, it seems likely that there has been selection to confer information regarding caller identity, but mechanisms leading to site-level variation in trill rate remain to be determined. published

We have achieved monolithic integration of photodetectors, DFB- and DBR lasers, SOAs, spot-size converters, polarization-rotators and splitters, EAMs, and passive-waveguide devices on InP technology. This generic foundry process provides endless possibilities for PIC designers.

This special issue includes 19 papers on InP integrated photonics capturing some of the most important recent advances, and providing a reference point for current state of the art.

We demonstrate PDM-PAM4 generation for the first time from an integrated EAM-based chip with 0.5 mm2 footprint. The device is used in 112 Gbit/s transmission over 80 km of SSMF.

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.

While the vast majority of genome size variation in plants is due to differences in repetitive sequence, we know little about how selection acts on repeat content in natural populations. Here we investigate parallel changes in intraspecific genome size and repeat content of domesticated maize (Zea mays) landraces and their wild relative teosinte across altitudinal gradients in Mesoamerica and South America. We combine genotyping, low coverage whole-genome sequence data, and flow cytometry to test for evidence of selection on genome size and individual repeat abundance. We find that population structure alone cannot explain the observed variation, implying that clinal patterns of genome size are maintained by natural selection. Our modeling additionally provides evidence of selection on individual heterochromatic knob repeats, likely due to their large individual contribution to genome size. To better understand the phenotypes driving selection on genome size, we conducted a growth chamber experiment using a population of highland teosinte exhibiting extensive variation in genome size. We find weak support for a positive correlation between genome size and cell size, but stronger support for a negative correlation between genome size and the rate of cell production. Reanalyzing published data of cell counts in maize shoot apical meristems, we then identify a negative correlation between cell production rate and flowering time. Together, our data suggest a model in which variation in genome size is driven by natural selection on flowering time across altitudinal clines, connecting intraspecific variation in repetitive sequence to important differences in adaptive phenotypes.Author summaryGenome size in plants can vary by orders of magnitude, but this variation has long been considered to be of little to no functional consequence. Studying three independent adaptations to high altitude inZea mays, we find that genome size experiences parallel pressures from natural selection, causing a linear reduction in genome size with increasing altitude. Though reductions in repetitive content are responsible for the genome size change, we find that only those individual loci contributing most to the variation in genome size are individually targeted by selection. To identify the phenotype influenced by genome size, we study how variation in genome size within a single teosinte population impacts leaf growth and cell division. We find that genome size variation correlates negatively with the rate of cell division, suggesting that individuals with larger genomes require longer to complete a mitotic cycle. Finally, we reanalyze data from maize inbreds to show that faster cell division is correlated with earlier flowering, connecting observed variation in genome size to an important adaptive phenotype.

© 2014, The New York Botanical Garden. 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.

We demonstrate an integrated transmitter that can generate two 100-Gb/s optical channels with simple nonreturn-to-zero-ON-OFF keying format. The transmitter is based on the combination of an ultrafast electro-optic polymer platform for the photonic integration and the optical modulation with ultrafast InP-double heterojunction bipolar transistor electronics for the multiplexing and the amplification of the 100-Gb/s driving signals. Through error-free transmission of 2 × 80-Gb/s signals over 1 km of SMF and transmission of 2 × 100-Gb/s signals over 500 m of single-mode fiber with error performance way below the forward error correction limit, we reveal the potential of the approach for parallel 100-GbE optical interfaces in small footprint transceivers for intradata center networks.

A series of tunable filters based on silicon nitride waveguide Bragg gratings buried in polymer are studied, fabricated and analyzed. The gratings are etched completely through the waveguides to improve the peak reflectivity at short grating lengths. Reflectivity from 1% to 70% can be reached when the third-order grating length varies from 16 µm to 160 µm. The experimental results are in good agreement with numerical simulations. Due to its compact size and the thermal advantages of polymer, the filter can be tuned very efficiently by a micro heater buried beneath. A tuning range of 34.5 nm is demonstrated at a heat power of only 22 mW.

The primary predators of primates are all ambush hunters, and yet felids, raptors, and snakes differ in aspects of their ecology that affect the evasive strategies of their primate prey. Felids and raptors can traverse long distances quickly, thus the urgency of threat they present increases as they come closer in proximity to primates. In contrast, snakes do not move rapidly over long distances, and so primates may be reasonably safe even at close distances provided snakes can be detected and monitored. We investigated the ability of captive rhesus macaques (Macaca mulatta) to detect snakes at distances ranging from 15 to 1.5 m. We also examined variation in intensity of perceived threat by applying a Hidden Markov Model to infer changes in underlying state from observable behaviors, that is, increased attention and mobbing. We found that the macaques often failed to detect snake models but that closer proximity improved snake detection, which is necessary before threat can be perceived. We also found that having only one individual in fairly close proximity (≤7.5 m) was sufficient to alert the rest of the group and so the chances of detection did not increase with increasing group size. Finally, we found that when the snakes were perceived, they did not elicit greater intensity of response with closer proximity. These results provide evidence that the threat from snakes is greatest when they are in proximity to primates but are unseen. When snakes are seen, however, distance appears not to affect primates' perceived risk, in contrast to their perceived risk from raptors and felids. Am. J. Primatol. 76:135–145, 2014. © 2013 Wiley Periodicals, Inc.

When adult males are temporarily away from the household,observational evidence suggests cross-culturaland intra-cultural variation in the effects of their absence on the labor ofother householdmembers.Insubsistence-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.

This chapter is devoted to photonic integrated circuits (PIC) on InP semiconductor basis. This materials platform is capable of monolithically integrating not only passive optical waveguide and receiver (Rx) devices but also transmitter (Tx) type structures, in particular optical amplifiers and lasers. In the first part the principal integration approaches of these diverse device structures will be addressed: vertical integration schemes relying on evanescent optical coupling between vertically stacked device levels; and lateral integration schemes exploiting in-plane optical coupling of the optical devices. In the latter case, butt-joint coupling, selective-area-growth, and quantum-well intermixing are being used, all of them geared to accomplish lateral band gap engineering. In the following section, recent examples of PICs based on proprietary technology solutions will be given. The second part of this chapter discusses generic photonic integration copying the foundry model successfully established in the electronics world. In this model, using defined building blocks, PIC design and manufacturing are strictly separated, thereby facilitating open access to this technology. As an example of such a generic platform, the TxRx technology developed by Fraunhofer HHI will be outlined. Selected building blocks will be described, and representative PICs made on multi-project wafer runs will be shown highlighting the viability of the foundry approach. In addition, the supply chain required for successful adoption of the foundry model will be briefly covered, including the design software environment, testing and wafer validation capabilities, and also generic packaging.

In this work, we report on experimental results of a fully integrated polarization converter made in InP. The device relies on slanted side wall waveguides. Using a novel design, we are able to demonstrate 15 dB of polarization extinction ratio (PER) for a fabrication tolerance of > 250 nm with respect to the critical waveguide width. The design of the device was derived using a new fully analytical model. No active tuning is required.

Selective area growth (SAG) technology has been added to an established InP monolithic integration platform to fabricate arrays of multi-wavelength distributed feedback (DFB) lasers. The local epitaxy growth rate is controlled by the SiO 2 mask width, and different quantum well (QW) thicknesses can be obtained in one run. The laser wavelengths span from 1447 nm to 1602 nm. The DFB lasers may include amplifying sections at the front and/or rear side. Output power up to 18 mW is achieved. This technology opens up possibilities to integrate various passive and active components such as lasers, modulators, detectors with different operating wavelengths monolithically on one wafer with less regrowth steps and reduced fabrication complexity.

Downloaded from http://rspb.royalsocietypublishing.org/ on March 16, 2016 rspb.royalsocietypublishing.org Comment Cite this article: Towner MC, Grote MN, Borgerhoff Mulder M. 2016 Problems modelling behavioural variation across Western North American Indian societies. Proc. R. Soc. B http://dx.doi.org/10.1098/rspb.2015.2184 Received: 10 September 2015 Accepted: 8 December 2015 Author for correspondence: Mary C. Towner e-mail: mary.towner@okstate.edu The accompanying reply can be viewed at http://dx.doi.org/10.1098/rspb.2016.0177. Problems modelling behavioural variation across Western North American Indian societies Mary C. Towner 1 , Mark N. Grote 2 and Monique Borgerhoff Mulder 2 Department of Integrative Biology, Oklahoma State University, Stillwater, OK 74078, USA Department of Anthropology, University of California, Davis, CA 95616, USA MCT, 0000-0002-0784-1860 Mathew & Perreault [1] analyse cross-cultural data from the Western North Amer- ican Indian (WNAI) dataset [2] in order to compare ‘the relative effect of environment and cultural history’ on behavioural variation across 172 societies. This endeavour is inspired by many other evolutionary studies of human cultural variation [3–7]. Mathew and Perreault conclude that ‘social learning operating over multiple generations [is] the main mode by which humans acquire their behaviour’ (p. 5). Our own investigation of cultural macroevolution in the WNAI [8] motivated us to attempt to reconstruct their analyses. we found their paper to be undermined by questionable analytical choices, and computational and data-handling pro- blems. We draw this conclusion having used the information in the Methods and electronic supplementary material S1, S3, S4 and S6 in [1] to recreate those parts of their study that we were able to. In this commentary, we present the results of our examination and detail the serious methodological flaws that lead us to con- clude that a complete re-analysis is required by Mathew and Perreault. We also comment briefly on their conceptual schema, which, in trying to find ‘the main mode of human adaptation’ [1], appears to set cultural transmission (i.e. social learning) in opposition to environmental adaptation. Mathew and Perreault use logistic regression to model 457 present/absent be- havioural traits as a function of three dimensions—E (local ecological conditions), P ( phylogenetic or linguistic distance to other societies) and S (spatial or geo- graphical distance to other societies). To judge the relative importance of the E, P and S classes of predictors, Mathew and Perreault compare sums of absolute values of regression coefficients across classes, for the best model of each behav- ioural trait. The ‘summed absolute values’ metric is used for various purposes in model and feature selection [9,10]. The metric is problematic here, however, because it compounds statistical signal with different sizes of the E, P and S classes. To demonstrate, consider a null case in which none of the predictors in E, P or S are related to a trait and the regression coefficients resemble stochastic noise. The analyst must understand how a statistical metric would behave in such a case and choose an inference procedure that reliably distinguishes null from non-null cases. For concreteness, assume that the coefficients share a common Gaussian distribution with mean zero and variance s 2 . The absolute value of a coefficient b then has expectation ð2 s 2 = p Þ 1=2 , and for a class containing M predictors the summed absolute values have expectation P E½ M . The null expectation therefore scales linearly with i¼1 j b i j ¼ Mð2 s = p Þ class size M, and larger classes of predictors will appear to have greater relative importance based on representation alone. Although model selection criteria such as AIC (discussed below) include a penalty for the number of predictors in a model, this does not mitigate the confounding effects of class size [11]. To see how summed absolute values depend on the number of predictors contributing to the sum, consider fig. 3 of [1], which appears to show a time- depth effect of language. The numbers of predictors in phylogenetic classes, from the Level 8 class down to the Level 3 class, follow a descending sequence: M ¼ 8, 8, 6, 4, 4, 3 (see electronic supplementary material S7 in [1]). This sequence is mirrored by the stair-step feature of the overall effect of phylogeny and is & 2016 The Author(s) Published by the Royal Society. All rights reserved.

The selective advantages to primates of trichromatic color vision, allowing discrimination among the colors green, yellow, orange, and red, remain poorly understood. We test the hypothesis that, for primates, an advantage of trichromacy over dichromacy, in which such colors are apt to be confused, lies in the detection of yellow, orange, or red (YOR) food patches at a distance, while controlling for the potentially confounding influences of reproductive status and memory of food patch locations. We employ socially monogamous titi monkeys (Callicebus brunneus) which, like most platyrrhine primates, have polymorphic color vision resulting in populations containing both dichromatic and trichromatic individuals. Wild Callicebus brunneus spent most foraging time in YOR food patches, the locations of most of which were likely to have been memorable for the subjects. Overall, both dichromatic and trichromatic females had significantly higher encounter rates than their dichromatic male pair mates for low-yield ephemeral YOR food patches whose locations were less likely to have been remembered. We detected no difference in the encounter rates of dichromatic and trichromatic females for such patches. However, the data suggest that such a difference may be detectable with a larger sample of groups of Callicebus brunneus, a larger sample of foraging observations per group, or both. We propose that a trichromatic advantage for foraging primates may be realized only when individuals’ energy requirements warrant searching for nonmemorable YOR food patches, a context for selection considerably more limited than is often assumed in explanations of the evolution of primate color vision.

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 analysis supports key IFD predictions. A Bayesian model fitted with the Gibbs sampler allows us to reconstruct 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 behavioral ecology interpretation of settlement history, human population expansion, and economic intensification in this region. They also demonstrate Bayesian analytical methods capable of making full use of the information available in archaeological datasets.

The direct involvement of the human leukocyte antigen class II DR-DQ genes in type 1 diabetes (T1D) is well established, and these genes display a complex hierarchy of risk effects at the genotype and haplotype levels. We investigated, using data from 38 studies, whether the DR-DQ haplotypes and genotypes show the same relative predispositional effects across populations and ethnic groups. Significant differences in risk within a population were considered, as well as comparisons across populations using the patient/control (P/C) ratio. Within a population, the ratio of the P/C ratios for two different genotypes or haplotypes is a function only of the absolute penetrance values, allowing ranking of risk effects. Categories of consistent predisposing, intermediate ('neutral'), and protective haplotypes were identified and found to correlate with disease prevalence and the marked ethnic differences in DRB1-DQB1 frequencies. Specific effects were identified, for example for predisposing haplotypes, there was a statistically significant and consistent hierarchy for DR4 DQB1*0302s: DRB1*0405 =*0401 =*0402 > *0404 > *0403, with DRB1*0301 DQB1*0200 (DR3) being significantly less predisposing than DRB1*0402 and more than DRB1*0404. The predisposing DRB1*0401 DQB1*0302 haplotype was relatively increased compared with the protective haplotype DRB1*0401 DQB1*0301 in heterozygotes with DR3 compared with heterozygotes with DRB1*0101 DQB1*0501 (DR1). Our results show that meta-analyses and use of the P/C ratio and rankings thereof can be valuable in determining T1D risk factors at the haplotype and amino acid residue levels.