South American Sites Research Articles

From modern-day parasitology to paleoparasitology: the elusive past record and evolution of Cryptosporidium.

Recent efforts have been made to review the state of the art on a variety of questions and targets in paleoparasitology, including protozoan taxa. Meanwhile, these efforts seemed to let aside Cryptosporidium, and we then intended to review its paleoparasitological record to assess its past distribution and favored detection methods, and eventually highlight needed research trajectories. This review shows that contrary to other parasites, most of the positive results came from South-American sites and coprolites rather than sediment samples, highlighting the need to test this kind of material, notably in Europe where many negative results were reported in the published literature from sediment samples. Moreover, aDNA-based detections are nearly absent from the paleoparasitological record of this parasite, though punctually shown successful. With their potential to address the evolutionary history of Cryptosporidium species, notably through their 18S rRNA tree, aDNA-based approaches should be encouraged in the future. In sum, and though the limits of currently used methods and materials remain unclear, this review highlights the potential role of coprolites and aDNA for the study of Cryptosporidium species in the past and how this history shaped their current diversity and distribution, notably among human populations but also farm animals.

Accuracy of five ground heat flux empirical simulation methods in the surface-energy-balance-based remote-sensing evapotranspiration models

Abstract. Based on the assessment from 230 flux site observations, intra-day and daytime ground heat flux (G) accounted for 19.2 % and 28.8 % of the corresponding net radiation, respectively. This indicates that G plays an important role in remote-sensing (RS) energy-balance-based evapotranspiration (ET) models. The G empirical estimation methods have been evaluated at many individual sites, while there have been relatively few multi-site evaluation studies. The accuracy of the five empirical G simulation methods in the surface-energy-balance-based RS–ET models was evaluated using half-hourly observations. The linear coefficient (LC) method and the two methods embedded with the normalized difference vegetation index (NDVI) were able to accurately simulate a half-hourly G series at most sites. The mean and median Nash–Sutcliffe efficiency (NSE) values of all sites were generally higher than 0.50 in each half-hour period. The accuracy of each method varied significantly at different sites and at half-hour intervals. The highest accuracy was exhibited during 06:00–07:00 LST (all times hereafter are LST), followed by the period of 17:00–18:00. There were 92 % (211/230) sites with an NSE of the LC method greater than 0.50 at 06:30. It showed a slightly higher accuracy during nighttime periods than during daytime periods. The lowest accuracy was observed during the period of 10:00–15:30. The sites with an NSE exceeding 0.50 only accounted for 51 % (118/230) and 43 % (100/230) at 10:30 and 13:30, respectively. The accuracy of the model was generally higher in Northern Hemisphere sites than in Southern Hemisphere sites. In general, the highest and lowest accuracies were observed at the high- and low-latitude sites, respectively. The performance of the LC method and the methods embedded with NDVI were generally satisfactory at the Eurasian and North American sites, with the NSE values of most sites exceeding 0.70. Conversely, it exhibited relatively poor performance at the African, South American, and Oceanian sites, especially the African sites. Both the temporal and spatial distributions of the accuracy of the G simulation were positively correlated with the correlation between G and the net radiation. Although the G simulation methods accurately simulated the G series at most sites and time periods, their performance was poor at some sites and time periods. The application of RS ET datasets covering these sites requires caution. Further improvement of G simulations at these sites and time periods is recommended for the RS ET modelers. In addition, variable parameters are recommended in empirical methods of G simulation to improve accuracy. Instead of the Rn, finding another variable that has a physical connection and strong correlation with G might be a more efficient solution for the improvement, since the weak correlation between G and Rn is the main reason for the poor performance at these regions.

Human Milk Oligosaccharide Compositions Illustrate Global Variations in Early Nutrition

BackgroundHuman milk oligosaccharides (HMOs) are an abundant class of compounds found in human milk and have been linked to the development of the infant, and specifically the brain, immune system, and gut microbiome. ObjectivesAdvanced analytical methods were used to obtain relative quantitation of many structures in approximately 2000 samples from over 1000 mothers in urban, semirural, and rural sites across geographically diverse countries. MethodsLC-MS−based analytical methods were used to profile the compounds with broad structural coverage and quantitative information. The profiles revealed their structural heterogeneity and their potential biological roles. Comparisons of HMO compositions were made between mothers of different age groups, lactation periods, infant sexes, and residing geographical locations. ResultsA common behavior found among all sites was a decrease in HMO abundances during lactation until approximately postnatal month 6, where they remained relatively constant. The greatest variations in structural abundances were associated with the presence of α(1,2)-fucosylated species. Genomic analyses of the mothers were not performed; instead, milk was phenotyped according to the abundances of α(1,2)-fucosylated structures. Mothers from the South American sites tended to have higher proportions of phenotypic secretors [mothers with relatively high concentrations of α(1,2)-fucosylated structures] in their populations compared to the rest of the globe, with Bolivia at ∼100% secretors, Peru at ∼97%, Brazil at ∼90%, and Argentina at ∼85%. Conversely, the cohort sampled in Africa manifested the lowest proportion of secretors (South Africa ∼ 63%, the Gambia ∼ 64%, and Malawi ∼ 75%). Furthermore, we compared total abundances of HMOs in secretors compared with nonsecretors and found that nonsecretors have lower abundances of HMOs compared to secretors, regardless of geographical location. We also observed compositional differences of the 50+ most abundant HMOs between milk types and geographical locations. ConclusionsThis study represents the largest structural HMO study to date and reveals the general behavior of HMOs during lactation among different populations.

The Ruditayoj-Tunasniyoj fossil area (Chuquisaca, Bolivia): a Triassic chirotheriid megatracksite and reinterpretation of purported thyreophoran tracks

ABSTRACT The South American tetrapod track record is highly diverse and well known mainly from Argentina, Brazil, Bolivia, Chile and Peru. To date, many tracksites are known from Bolivia, most studied during the past century. From the Jurassic-Cretaceous La Puerta Formation of the Tunasniyoj locality (Incapampa-Icla syncline) thyreophoran trackways have previously been described. New geological studies related with the Central Atlantic Magmatic Province in Bolivia recognised the track-bearing unit as the Ipaguazú Formation, dated as Late Triassic in age. In this significantly new context, we present here a new track-bearing locality: Ruditayoj, neighbour to Tunasniyoj, near Icla, Chuquisaca, Bolivia. A detailed study of the trackways from this new site allowed new interpretations consistent with the geological context. Hundreds of Brachychirotherium trackways are present at the site with a wide diversity of preservational types. Behavioural issues such as gregariousness and grouping around ponds are suggested. Trackway parameters, track size and shape support large ‘rauisuchid’ or aetosaur pseudosuchian producers. Previous assignations to thyreophoran producers are discussed. This is the first record of Brachychirotherium from Bolivia, filling the lack of information about suchian fossils, well known in other South American sites.

The organization of production for Inka Polychrome pottery from Pachacamac, Peru

This study investigates the organization of production for Inka Polychrome pottery used at the Temple of the Sun, Pachacamac. Inka Polychrome pottery was critical to imperial strategies for managing state power in the provinces. It was highly standardized in appearance yet is known to have been produced at many locations throughout the empire by Inka and subject potters. Pachacamac was an important political and ideological location on the central coast that was transformed by the Inka after C.E. 1470 into a major imperial center. To evaluate the production and source of pottery at Pachacamac, a sample of 149 ceramics in local, Inka Polychrome, and Regional Inka styles were evaluated using neutron activation analysis to identify compositional groups. Attributes related to the production and decoration of these ceramic artifacts were recorded and statistically compared between groups. Compositional data from this analysis was also compared to compositional data from ceramics excavated from other South American sites and analyzed at the Lawrence Berkeley National Laboratory. Results found that multiple groups of potters at multiple places (some of which are local) produced this pottery, and small amounts of pottery are being imported.

A Review of Ethnographic Use of Wooden Spears and Implications for Pleistocene Hominin Hunting

Wooden spears are amongst the earliest weapons known from the archaeological record, with broken and complete examples known from Middle and Late Pleistocene Eurasian, Australian and South American sites. They were manufactured and used by multiple species of <em>Homo</em>, including <em>H. sapiens</em>. This paper comprises the first systematic review of ethnographic data on the recent use of wooden spears for hunting and human violence. It confronts the historical racism underpinning the abuse of ethnographic data on wooden spears, including associations between the technology and the development of cognitive abilities in human evolution. The review demonstrates that wooden spears were used as thrusting and throwing weapons by recent societies in North America, South America, Africa, and Oceania, and continue to be used today by children as training tools in hunter-gatherer societies. Their use is recorded in a wide range of climates and environments, using a variety of different hunting strategies to target terrestrial and aquatic prey. Whilst acknowledging limitations of ethnographic datasets, Middle and early Late Pleistocene hominin hunting is reconsidered, briefly overviewing wooden spears in relation to the variety of climate and ecological settings in which Pleistocene hominins hunted, targeted prey, and the potential for delivery methods and hunting strategies. The results underscore the importance of systematic reviews when utilising ethnography in interpreting archaeological evidence: selective references in relation to the use of wooden spears have overlooked additional examples that point to a richness and variability of technology and behaviour that is invisible in the Pleistocene archaeological record.

Mechanisms of Convergent Egg Provisioning in Poison Frogs.

Parental provisioning of offspring with physiological products (nursing) occurs in many animals, yet little is known about the neuroendocrine basis of nursing in non-mammalian species. Within amphibians, maternal provisioning has evolved multiple times, with mothers of some species feeding unfertilized eggs to their developing offspring until tadpoles complete metamorphosis [1-3]. We conducted field studies in Ecuador and Madagascar to ask whether convergence at the behavioral level provides similar benefits to offspring and relies on shared neural mechanisms in dendrobatid and mantellid poison frogs. At an ecological level, we found that nursing allows poison frogs to provide chemical defenses to their tadpoles in both species. At the neural level, nursing was associated with increased activity in the lateral septum and preoptic area, demonstrating recruitment of shared brain regions in the convergent evolution of nursing within frogs and across vertebrates [4]. In contrast, only mantellids showed increased oxytocin neuron activity akin to that in nursing mammals [5], suggesting evolutionary versatility in molecular mechanisms. Our findings demonstrate that maternal provisioning provides similar potential benefits to offspring and relies on similar brain regions in poison frog species with convergently evolved toxicity and maternal care. VIDEO ABSTRACT.

Efficacy of Therapies Following Venetoclax Discontinuation in CLL: Focus on B-Cell Receptor Signal Transduction Inhibitors and Cellular Therapies

Efficacy of Therapies Following Venetoclax Discontinuation in CLL: Focus on B-Cell Receptor Signal Transduction Inhibitors and Cellular Therapies

High-Density Mapping of Triple Rust Resistance in Barley Using DArT-Seq Markers.

The recent availability of an assembled and annotated genome reference sequence for the diploid crop barley (Hordeum vulgare L.) provides new opportunities to study the genetic basis of agronomically important traits such as resistance to stripe [Puccinia striiformis f. sp. hordei (Psh)], leaf [P. hordei (Ph)], and stem [P. graminis f. sp. tritici (Pgt)] rust diseases. The European barley cultivar Pompadour is known to possess high levels of resistance to leaf rust, predominantly due to adult plant resistance (APR) gene Rph20. We developed a barley recombinant inbred line (RIL) population from a cross between Pompadour and the leaf rust and stripe rust susceptible selection Biosaline-19 (B-19), and genotyped this population using DArT-Seq genotyping by sequencing (GBS) markers. In the current study, we produced a high-density linkage map comprising 8,610 (SNP and in silico) markers spanning 5957.6 cM, with the aim of mapping loci for resistance to leaf rust, stem rust, and stripe rust. The RIL population was phenotyped in the field with Psh (Mexico and Ecuador) and Ph (Australia) and in the greenhouse at the seedling stage with Australian Ph and Pgt races, and at Wageningen University with a European variant of Psh race 24 (PshWUR). For Psh, we identified a consistent field QTL on chromosome 2H across all South American field sites and years. Two complementary resistance genes were mapped to chromosomes 1H and 4H at the seedling stage in response to PshWUR, likely to be the loci rpsEm1 and rpsEm2 previously reported from the cultivar Emir from which Pompadour was bred. For leaf rust, we determined that Rph20 in addition to two minor-effect QTL on 1H and 3H were effective at the seedling stage, whilst seedling resistance to stem rust was due to QTL on chromosomes 3H and 7H conferred by Pompadour and B-19, respectively.

Rasgos diagnósticos en elementos postcraneales de dos especies de otáridos para su identificación en el registro zooarqueológico

Arctocephalus australis and Otaria flavescens are the two species of otariids that frequently appear in the zooarchaeological record of South American coastal sites. The similarity between their postcranial bone elements has limited taxonomic identification, resulting in one of the greatest difficulties encountered to carry out detailed zooarchaeological analysis of these animals. The aim of this study is to present a clear descriptive criterion that can be used to identify these two species when recovered from the zooarchaeological record. The use of diagnostic traits along with other approaches (e.g., osteometric studies, bone fusion schedule), will allow investigating particular aspects of the fossil record of these animals. From a sample of 24 modern adult individuals, earlier proposed criteria were reviewed, and as a result, a new list of 36 diagnostic traits for postcranial skeleton bones is presented.

Effect of geographical latitude and sun exposure on Rufous Hornero (Furnarius rufus) nest orientation

Bird nest orientation is affected by environmental variables determined by their geographical position as well as microclimatic conditions. In closed-cup-nesting species, nests may be oriented to avoid adverse environmental extremes such as sun exposure, wind, and rainfall, although vegetal cover may provide extra protection generating random orientation patterns. Here, we assess nest entrance orientation in Rufous Hornero (Furnarius rufus) at 11 South American sites by comparing nests well covered by vegetation (> 75% covered) from those with less or non-external vegetal protection (< 25%). We estimated and compared mean entrance orientation between northern and southern locations and levels of vegetation cover using circular statistics (n = 1291). Additionally, the influence of geographical latitude and vegetation cover on nest orientation was evaluated using linear mixed models across sites with non-random nest-orientation patterns. Results showed differences in mean orientation values between covered and uncovered nests at most locations and directed entrance orientation for uncovered nests. On the other hand, the models indicate that nest entrance orientation is not affected by the joint effect of latitude and vegetation cover and high variability between locations. Local microclimatic conditions provided by the vegetation above nests are important determinants for nest orientation in the species, although additional information about local rainfall, wind, temperature, and nesting site availability may help to determine the factors affecting orientation in the species on a local level.

Global Validation of MODIS C6 and C6.1 Merged Aerosol Products over Diverse Vegetated Surfaces

In this study, the MODerate resolution Imaging Spectroradiometer (MODIS) Collections 6 and 6.1 merged Dark Target (DT) and Deep Blue (DB) aerosol products (DTBC6 and DTBC6.1) at 0.55 µm were validated from 2004–2014 against Aerosol Robotic Network (AERONET) Version 2 Level 2.0 AOD obtained from 68 global sites located over diverse vegetated surfaces. These surfaces were categorized by static values of monthly Normalized Difference Vegetation Index (NDVI) observations obtained for the same time period from the MODIS level-3 monthly NDVI product (MOD13A3), i.e., partially/non–vegetated (NDVIP ≤ 0.3), moderately–vegetated (0.3 &lt; NDVIM ≤ 0.5) and densely–vegetated (NDVID &gt; 0.5) surfaces. The DTBC6 and DTBC6.1 AOD products are accomplished by the NDVI criteria: (i) use the DT AOD retrievals for NDVI &gt; 0.3, (ii) use the DB AOD retrievals for NDVI &lt; 0.2, and (iii) use an average of the DT and DB AOD retrievals or the available one with highest quality assurance flag (DT: QAF = 3; DB: QAF ≥ 2) for 0.2 ≤ NDVI ≤ 0.3. For comparison purpose, the DTBSMS AOD retrievals were included which were accomplished using the Simplified Merge Scheme, i.e., use an average of the DTC6.1 and DBC6.1 AOD retrievals or the available one for all the NDVI values. For NDVIP surfaces, results showed that the DTBC6 and DTBC6.1 AOD retrievals performed poorly over North and South America in terms of the agreement with AERONET AOD, and over Asian region in terms of retrievals quality as the small percentage of AOD retrievals were within the expected error (EE = ± (0.05 + 0.15 × AOD). For NDVIM surfaces, retrieval errors and poor quality in DTBC6 and DTBC6.1 were observed for Asian, North American and South American sites, whereas good performance, was observed for European and African sites. For NDVID surfaces, DTBC6 does not perform well over the Asian and North American sites, although it contains retrievals only from the DT algorithm which was developed for dark surfaces. Overall, the performance of the DTBC6.1 AOD retrievals was significantly improved compared to the DTBC6, but still more improvements are required over NDVIP, NDVIM and NDVID surfaces of Asia, NDVIM and NDVID surfaces of North America, and NDVIM surfaces of South America. The performance of the DTBSMS retrievals was better than the DTBC6 and DTBC6.1 retrievals with 11–13% (31%) greater number of coincident observations, 6–9% (14–22%) greater percentage of retrievals within the EE, and 30–100% (46–100%) smaller relative mean bias compared to the DTBC6.1 (DTBC6) at a global scale.

The Hyalella (Crustacea: Amphipoda) species cloud of the ancient Lake Titicaca originated from multiple colonizations

Ancient lakes are renowned for their exceptional diversity of endemic species. As model systems for the study of sympatric speciation, it is necessary to understand whether a given hypothesized species flock is of monophyletic or polyphyletic origin. Here, we present the first molecular characterization of the Hyalella (Crustacea: Amphipoda) species complex of Lake Titicaca, using COI and 28S DNA sequences, including samples from the connected Small and Large Lakes that comprise Lake Titicaca as well as from a broader survey of southern South American sites. At least five evolutionarily distant lineages are present within Lake Titicaca, which were estimated to have diverged from one another 12–20 MYA. These major lineages are dispersed throughout the broader South American Hyalella phylogeny, with each lineage representing at least one independent colonization of the lake. Moreover, complex genetic relationships are revealed between Lake Titicaca individuals and those from surrounding water bodies, which may be explained by repeated dispersal into and out of the lake, combined with parallel intralacustrine diversification within two separate clades. Although further work in deeper waters will be required to determine the number of species present and modes of diversification, our results strongly indicate that this amphipod species cloud is polyphyletic with a complex geographic history.

Application of non-destructive XRF method to the study of the provenance for archaeological obsidians from Italian, Central European and South American sites

This paper presents the results of the attribution of approximately 1700 artifacts, from Italian, Central European and South American sites to the geological obsidian sources. The provenance was determined using the non-destructive X-ray Fluorescence (XRF) analytical method, based on the secondary X-ray intensity proposed by Crisci et al. (1994) and optimized by De Francesco et al. (2008).In the first phase of the research, to test the non-destructive XRF method, the analysis on entire obsidian fragments (similar to archaeological waste) was initially carried out on 60 samples representative of all the geological outcrops in the Mediterranean region. The secondary X-ray intensities obtained by non-destructive XRF on whole pieces were compared with the results using the XRF method on powders, carried out on the same samples (major elements, and selected trace elements, such as Nb, Y, Zr, Rb and Sr) as exhaustively described in De Francesco et al. (2008). These five trace elements were sufficient to characterize (by both methods) the different places of obsidian origin, because they are particularly indicative of the genetic processes that produced obsidian.The provenance of the obsidian artifacts was determined by comparing the X-rays intensity ratios of the selected elements with those obtained on the entire fragments of the obsidian sources in the Mediterranean.The purpose of this paper is to show the results obtained in almost two decades of the application of the non-destructive XRF method. About 1700 archaeological obsidian fragments, from numerous Italian, Corsican, central European (Romanian) and South American (Central-western Argentina and Central Chile) archaeological sites, have been analyzed by non-destructive XRF, and assigned to obsidian sources. The provenance of 97% of the obsidian artifacts was successfully determined.The results demonstrate that the non-destructive XRF method - thanks to its sensitivity, low cost, and high speed - is an extremely valuable tool for the attribution of the provenance of archaeological obsidian in the areas under consideration.

Modelling tree ring cellulose &amp;lt;i&amp;gt;δ&amp;lt;/i&amp;gt;&amp;lt;sup&amp;gt;18&amp;lt;/sup&amp;gt;O variations in two temperature-sensitive tree species from North and South America

Abstract. Oxygen isotopes in tree rings (δ18OTR) are widely used to reconstruct past climates. However, the complexity of climatic and biological processes controlling isotopic fractionation is not yet fully understood. Here, we use the MAIDENiso model to decipher the variability in δ18OTR of two temperature-sensitive species of relevant palaeoclimatological interest (Picea mariana and Nothofagus pumilio) and growing at cold high latitudes in North and South America. In this first modelling study on δ18OTR values in both northeastern Canada (53.86° N) and western Argentina (41.10° S), we specifically aim at (1) evaluating the predictive skill of MAIDENiso to simulate δ18OTR values, (2) identifying the physical processes controlling δ18OTR by mechanistic modelling and (3) defining the origin of the temperature signal recorded in the two species. Although the linear regression models used here to predict daily δ18O of precipitation (δ18OP) may need to be improved in the future, the resulting daily δ18OP values adequately reproduce observed (from weather stations) and simulated (by global circulation model) δ18OP series. The δ18OTR values of the two species are correctly simulated using the δ18OP estimation as MAIDENiso input, although some offset in mean δ18OTR levels is observed for the South American site. For both species, the variability in δ18OTR series is primarily linked to the effect of temperature on isotopic enrichment of the leaf water. We show that MAIDENiso is a powerful tool for investigating isotopic fractionation processes but that the lack of a denser isotope-enabled monitoring network recording oxygen fractionation in the soil–vegetation–atmosphere compartments limits our capacity to decipher the processes at play. This study proves that the eco-physiological modelling of δ18OTR values is necessary to interpret the recorded climate signal more reliably.

New customized methods for improvement of the MODIS C6 Dark Target and Deep Blue merged aerosol product

The Moderate resolution and Imaging Spectroradiometer (MODIS) level 2 operational aerosol products (MOD04/MYD04), based on the Dark Target (DT) and the enhanced Deep Blue (DB) algorithms, have been providing daily global aerosol information. The MOD04/MYD04 has different data coverage for the DT and the DB algorithms due to differences in their retrieval methods. Recently in the collection 6 (C6), a DT and DB merged (DTBC6) AOD product has been introduced based on different thresholds of the Normalized Difference Vegetation Index (NDVI) to improve the data coverage. The main objective of this study is to increase the data coverage and reduce the error in the merged DTBC6 AOD product by introducing three new customized methods (DTBMX): (i) DTBM1: “use an average of the DT and DB AOD retrievals or the available one for all the NDVI values ”, as it is independent of the NDVI values, (ii) DTBM2: “use an average of the DT and DB AOD retrievals or the available one for NDVI≥0.2, and use the DB retrievals for NDVI<0.2”, and (iii) DTBM3: “use AOD retrievals from the DB algorithm for NDVI>0.3, and use an average of the DT and DB retrievals or the available one for NDVI≤0.3”. Validation of the DTBMX is conducted at a global scale from 2004 to 2014 using AERONET AOD measurements from 68 sites located in Asia (9), Europe (22), Southern Africa (8), and North (23) and South America (8), and for comparison purpose, the DTBC6 is evaluated for the same period. Results showed that the number of coincident observations of the DTBMX methods compared to the DTBC6 is increased by 31%, 41% 30%, and 108% for Asian, European, Southern African, and North and South American sites, respectively. At global scale, the number of coincident observations are increased for the DTBM1, DTBM2, and DTBM3 from 29,088 for DTBC6, to 45,937, 45,028, 37,393 which are 58%, 57%, and 29%, respectively more than the for DTBC6 observations. For an equal number of coincident observations, the percentage of retrievals within the EE is increased by between 17% to 20% and the RMSE is decreased by up to 15% for the DTBMX methods, but R is the same as for the DTBC6. The percentage above the EE is also decreased by between 43% to 55% due to greater contribution of the DB retrievals. Overall, the performance of all the DTBMX methods is much better than the DTBC6, but the DTBM1 is the most robust as it is independent of NDVI values, and significantly increases the data coverage. Therefore, it can be used operationally for global merged AOD retrievals.

Genetic differentiation associated with host plants and geography among six widespread species of South American Blepharoneura fruit flies (Tephritidae).

Tropical herbivorous insects are astonishingly diverse, and many are highly host-specific. Much evidence suggests that herbivorous insect diversity is a function of host plant diversity; yet, the diversity of some lineages exceeds the diversity of plants. Although most species of herbivorous fruit flies in the Neotropical genus Blepharoneura are strongly host-specific (they deposit their eggs in a single host plant species and flower sex), some species are collected from multiple hosts or flowers and these may represent examples of lineages that are diversifying via changes in host use. Here, we investigate patterns of diversification within six geographically widespread Blepharoneura species that have been collected and reared from at least two host plant species or host plant parts. We use microsatellites to (1) test for evidence of local genetic differentiation associated with different sympatric hosts (different plant species or flower sexes) and (2) examine geographic patterns of genetic differentiation across multiple South American collection sites. In four of the six fly species, we find evidence of local genetic differences between flies collected from different hosts. All six species show evidence of geographic structure, with consistent differences between flies collected in the Guiana Shield and flies collected in Amazonia. Continent-wide analyses reveal - in all but one instance - that genetically differentiated flies collected in sympatry from different host species or different sex flowers are not one another's closest relatives, indicating that genetic differences often arise in allopatry before, or at least coincident with, the evolution of novel host use.

Fear of falling and its association with life-space mobility of older adults: a cross-sectional analysis using data from five international sites.

fear of falling (FOF) is a major health concern among community-dwelling older adults that could restrict mobility. to examine the association of FOF with life-space mobility (i.e. the spatial area a person moves through in daily life) of community-dwelling older adults from five diverse sites. in total, 1,841 older adults (65-74 years) were recruited from Kingston, Canada; Saint-Hyacinthe, Canada; Tirana, Albania; Manizales, Colombia and Natal, Brazil. FOF was assessed using the Fall Efficacy Scale-International (FES-I total score), and the life space was quantified using the Life-Space Assessment (LSA), a scale that runs from 0 (minimum life space) to 120 (maximum life space). the overall average LSA total score was 68.7 (SD: 21.2). Multiple-linear regression analysis demonstrated a significant relationship of FOF with life-space mobility, even after adjusting for functional, clinical and sociodemographic confounders (B = -0.15, 95% confidence interval (CI) -0.26 to -0.04). The FOF × site interaction term was significant with a stronger linear relationship found in the Canadian sites and Tirana compared with the South American sites. After adjusting for all confounders, the association between FOF with LSA remained significant at Kingston (B = -0.32, 95% CI -0.62 to -0.01), Saint-Hyacinthe (B = -0.81, 95% CI -1.31 to -0.32) and Tirana (B = -0.57, 95% CI -0.89 to -0.24). FOF is an important psychological factor that is associated with reduction in life space of older adults in different social and cultural contexts, and the strength of this association is site specific. Addressing FOF among older adults would help improve their mobility in local communities, which in turn would improve social participation and health-related quality of life.

Morphometry of a Pre‐Hispanic Dog from Northwestern Argentina (AD 800–1200)

AbstractA detailed morphometric description of a dog skull from the pre‐Hispanic archaeological site La Isla de Tilcara (northwestern Argentina, ca AD 800–1200) is presented. The resulting data were compared with those of dog skulls from other South American archaeological sites to establish dog morphotype. The examined skull belonged to a small, long‐snouted dog, similar to the smallest morphotypes from the central Andes. Copyright © 2016 John Wiley &amp; Sons, Ltd.

Investigation of biodegradation in three different sediment cores from a shellmound (sambaqui) of Brazil, using Ascaris lumbricoides eggs as a model

For more than 30years, paleoparasitologists attempted to recover parasite remains from burial sediments and archaeological layers in Brazilian shellmounds. These sites are located along the shoreline of the country especially at the South and Southeastern regions, and for that reason they are exposed to frequent rainfall. Most of the shellmounds were built in coastal plains, associated with waterbodies, under the influence of high tides and/or inundation. Biodegradation is a factor that affects parasite preservation, especially in open archaeological sites. However, this hypothesis has never been tested in sediments from shellmounds. This study aimed to experimentally evaluate the biodegradation of Ascaris lumbricoides eggs and DNA from three intact cores collected from a shellmound. The cores and control sediments were collected from archaeological profiles composed of different materials. Each core received about 1,000,000 recent eggs, and water was poured over twice a week during 45days, simulating the main climate condition of the environment. The water was collected at the end of each core to observe the egg movement through the archaeological layers of the cores. Soil was sampled in different levels: 31 soil samples from the cores and 12 control samples were analyzed by the spontaneous sedimentation technique and 23 soil samples from the cores and all the control samples were analyzed for the DNA of the parasite. Parasitological evidence was only found in the superficial layers and very few eggs were recovered. Bioactivity caused destruction of most of the eggs and DNA. This research also supports the previous hypothesis that taphonomic factors probably are responsible for fewer findings of A. lumbricoides eggs in South American archaeological sites, especially in open environment sites.