The genetic prehistory of human populations in Central America is largely unexplored leaving an important gap in our knowledge of the global expansion of humans. We report genome-wide ancient DNA ...data for a transect of twenty individuals from two Belize rock-shelters dating between 9,600-3,700 calibrated radiocarbon years before present (cal. BP). The oldest individuals (9,600-7,300 cal. BP) descend from an Early Holocene Native American lineage with only distant relatedness to present-day Mesoamericans, including Mayan-speaking populations. After ~5,600 cal. BP a previously unknown human dispersal from the south made a major demographic impact on the region, contributing more than 50% of the ancestry of all later individuals. This new ancestry derived from a source related to present-day Chibchan speakers living from Costa Rica to Colombia. Its arrival corresponds to the first clear evidence for forest clearing and maize horticulture in what later became the Maya region.
We report genome-wide ancient DNA from 49 individuals forming four parallel time transects in Belize, Brazil, the Central Andes, and the Southern Cone, each dating to at least ∼9,000 years ago. The ...common ancestral population radiated rapidly from just one of the two early branches that contributed to Native Americans today. We document two previously unappreciated streams of gene flow between North and South America. One affected the Central Andes by ∼4,200 years ago, while the other explains an affinity between the oldest North American genome associated with the Clovis culture and the oldest Central and South Americans from Chile, Brazil, and Belize. However, this was not the primary source for later South Americans, as the other ancient individuals derive from lineages without specific affinity to the Clovis-associated genome, suggesting a population replacement that began at least 9,000 years ago and was followed by substantial population continuity in multiple regions.
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•Genome-wide analysis of 49 Central and South Americans up to ∼11,000 years old•Two previously unknown genetic exchanges between North and South America•Distinct link between a Clovis culture-associated genome and the oldest South Americans•Continent-wide replacement of Clovis-associated ancestry beginning at least 9,000 years ago
A large-scale analysis of ancient genomes from Central and South America yields insights into the peopling of the Americas, including four southward population spreads and notable population continuity in much of South America after arrival.
Maize is a cultigen of global economic importance, but when it first became a staple grain in the Americas, was unknown and contested. Here, we report direct isotopic dietary evidence from 52 ...radiocarbon-dated human skeletons from two remarkably well-preserved rock-shelter contexts in the Maya Mountains of Belize spanning the past 10,000 years. Individuals dating before ~4700 calendar years before present (cal B.P.) show no clear evidence for the consumption of maize. Evidence for substantial maize consumption (~30% of total diet) appears in some individuals between 4700 and 4000 cal B.P. Isotopic evidence after 4000 cal B.P. indicates that maize became a persistently used staple grain comparable in dietary significance to later maize agriculturalists in the region (>70% of total diet). These data provide the earliest definitive evidence for maize as a staple grain in the Americas.
Habitat loss and fragmentation present major challenges for wildlife conservation since connectivity between suitable habitat patches is needed for dispersal, allowing for genetic exchange between ...populations. These exchanges can be particularly important in marginal habitats as they ensure the persistence of populations that are often most vulnerable to natural occurrences or anthropogenic activities. Medium-sized mammals can be particularly susceptible to changes in the landscape and their absence can be an indicator of habitat degradation. In this study, 6 pacas (Cuniculus paca), medium-sized mammals that are an important prey of large felids and a popular game species for hunters in Belize, were radiotracked in the Central Belize Corridor. Home range estimates for these were larger than those documented for pacas inhabiting broadleaf forests of Panama and Costa Rica. When broadleaf habitats were inaccessible due to flooding, pacas selected a savannah habitat with dense vegetation over more open grass savannahs. Knowledge of how pacas and other wildlife use the landscape in the wildlife corridor will allow more effective management by guiding the development of adequate regulations for hunting and resource exploitation.
Gray foxes are successful habitat generalists within the temperate zone of their geographic range, exploiting a wide variety of habitats, including human-dominated landscapes. However, little is ...known of their use of tropical habitats or their ability to exploit landscapes with human activity. Here, we report the first study to explore the ecology and behavior of gray foxes within the tropics. Extensive camera-trap data (23,598 trap nights) across two different landscapes in Belize, combined with telemetry data on three collared individuals, showed a preference for more open and drier habitats over tropical moist broadleaf forest which is the dominant habitat type in the region. Although foxes did not use the interior of the broadleaf forests, they were detected at the edges and readily exploited areas that had been converted to support human activities (e.g., tourist centers). Home ranges of collared individuals were relatively large (3–7 km
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) compared to those of temperate gray foxes, suggesting that they occupy a less productive landscape than those studied further north. This study found that although tropical gray foxes readily exploited human-altered landscapes, just as they do in the temperate zone, they are not the habitat generalists as previously thought and seem unable to fully exploit tropical moist broadleaf forest, the regions’ most dominant and productive habitat type.
Although the paca is the most frequently hunted game species throughout the Neotropics, its behavioral and ecological requirements remain poorly understood. Here, we describe ranging behavior, ...spatio-temporal intraspecific interactions, and cavity use within a mosaic landscape in Central Belize, based on radio-tracking of four males and two females. This study is the first to investigate social interactions and spatial structure within a paca population in unprotected marginal habitat. We detected extensive home range overlap between males and between sexes. Male-male overlap was less extensive within core areas, while female core ranges were almost entirely occupied by one or more males. On average, pacas used at least six cavities within their home range. The majority of cavities were in the core areas and we did not detect simultaneous co-habitation of the same location. On average, females occupied cavities that were closer together, and closer to water bodies, than those of males. Overall, our study suggests a general tolerance during nocturnal foraging activities, but exclusive use of core areas and associated cavities. The larger ranges of males than females and the extensive overlap between conspecifics suggest a polygamous or promiscuous mating system in this landscape.
Marking behaviors of jaguars (Panthera onca) and pumas (Puma concolor) were investigated by linking sign from transect surveys to species, sex, and individual detected by camera traps along trails in ...the Cockscomb Basin Wildlife Sanctuary, Belize. The most commonly encountered big-cat signs were scrape marks. These were produced by cats raking the ground with their feet. Scrapes were associated more strongly with presence of male pumas than with female pumas or jaguars of either sex. Scats found in scrapes were genotyped to species level and indicated that jaguars produced larger scrapes than pumas and that pumas were more likely to scrape with their hind feet than with front feet. Scrapes were spatially clustered along trails, indicating that individuals scrape in response to other scrapes in the same area. High scraping frequencies were not associated with the presence of specific individuals, suggesting that scrape-marking behavior does not signal dominance in this area.
OBJECTIVE:The International Patterns of Opioid Prescribing study compares postoperative opioid prescribing patterns in the United States (US) versus the rest of the world.
SUMMARY OF BACKGROUND ...DATA:The US is in the middle of an unprecedented opioid epidemic. Diversion of unused opioids contributes to the opioid epidemic.
METHODS:Patients ≥16 years old undergoing appendectomy, cholecystectomy, or inguinal hernia repair in 14 hospitals from 8 countries during a 6-month period were included. Medical records were systematically reviewed to identify(1) preoperative, intraoperative, and postoperative characteristics, (2) opioid intake within 3 months preoperatively, (3) opioid prescription upon discharge, and (4) opioid refills within 3 months postoperatively. The median/range and mean/standard deviation of number of pills and OME were compared between the US and non-US patients.
RESULTS:A total of 4690 patients were included. The mean age was 49 years, 47% were female, and 4% had opioid use history. Ninety-one percent of US patients were prescribed opioids, compared to 5% of non-US patients (P < 0.001). The median number of opioid pills and OME prescribed were 20 (0–135) and 150 (0–1680) mg for US versus 0 (0–50) and 0 (0–600) mg for non-US patients, respectively (both P < 0.001). The mean number of opioid pills and OME prescribed were 23.1 ± 13.9 in US and 183.5 ± 133.7 mg versus 0.8 ± 3.9 and 4.6 ± 27.7 mg in non-US patients, respectively (both P < 0.001). Opioid refill rates were 4.7% for US and 1.0% non-US patients (P < 0.001).
CONCLUSIONS:US physicians prescribe alarmingly high amounts of opioid medications postoperatively. Further efforts should focus on limiting opioid prescribing and emphasize non-opioid alternatives in the US.
The use of local Mediterranean food plants is at the brink of disappearance. Even though there is relatively abundant information on inventories of wild edible taxa, there is also a crucial need to ...understand how these plants are consumed and when and how these consumption phenomena change over time and place around the Mediterranean. Additionally, it is important to study such knowledge systems and find innovative ways of infusing them to the future Mediterranean generations. During the years 2003-2006 a circum-Mediterranean ethnobotanical field survey for wild food plants was conducted in selected study sites in seven Mediterranean areas (European Union-funded RUBIA Project). Structured and semi-structured questionnaires have been administered to indigenous people and 294 wild food plant taxa were documented in the survey. A comparative analysis of the data was undertaken showing that the quantity and quality of traditional knowledge varies among the several study areas and is closely related to the traditions, environment and cultural heritage of each country. More similarities of wild edible popular use were revealed between the Eastern Mediterranean and the Western Mediterranean.
A customized app in Open Data Kit (ODK) was used for data collection. Besides sociodemographic and clinical data, the app allows recording the geographic coordinates of the household and scanning the ...barcodes and entering screening results for each individual. Additional approval for publication was obtained from the Institutional Review Board (IRB) of the Institute of Tropical Medicine (ITM), Antwerp (Approval number: 1541/21). ...30 new leprosy cases were identified among the self-presenting neighborhood contacts as well as 6 additional new cases among their household contacts (Fig 1). In such high prevalence zones, even repeated (e.g., annual or biannual) door-to-door screening could be considered until clear signs of decline are demonstrated (e.g., until no more children are found among newly diagnosed leprosy cases). Since household contacts clearly are at extremely high risk, postexposure prophylaxis is strongly recommended 9.
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