Archaeobotanical evidence supports indigenous cucurbit long-term use in the Mesoamerican Neotropics.

The squash family (Cucurbitaceae) contains some of the most important crops cultivated worldwide and has played an important ecological, economic, and cultural role for millennia. In the American tropics, squashes were among the first cultivated crop species, but little is known about how their domestication unfolded. Here, we employ direct radiocarbon dating and morphological analyses of desiccated cucurbit seeds, rinds, and stems from El Gigante Rockshelter in Honduras to reconstruct human practices of selection and cultivation of Lagenaria siceraria, Cucurbita pepo, and Cucurbita moschata. Direct radiocarbon dating indicates that humans started using Lagenaria and wild Cucurbita starting ~ 10,950 calendar years before present (cal B.P.), primarily as watertight vessels and possibly as cooking and drinking containers. A rind directly dated to 11,150-10,765 cal B.P. represents the oldest known bottle gourd in the Americas. Domesticated C. moschata subsequently appeared ~ 4035 cal B.P., followed by domesticated C. pepo ~ 2190 cal B.P. associated with increasing evidence for their use as food crops. Multivariate statistical analysis of seed size and shape show that the archaeological C. pepo assemblage exhibits significant variability, representing at least three varieties: one similar to present-day zucchini, another like present-day vegetable marrow, and a native cultivar without modern analogs. Our archaeobotanical data supports the hypothesis that Indigenous cucurbit use started in the Early Holocene, and that agricultural complexity during the Late Holocene involved selective breeding that encouraged crop diversification.

Using human-centered design to develop a nurse-to-family telehealth intervention for pediatric transfers.

Objective: To develop a nurse-to-family telehealth intervention for pediatric inter-facility transfers using the human-centered design approach. Methods: We conducted the inspiration and ideation phases of a human-centered design process from July 2022 to December 2022. For the inspiration phase, we conducted a qualitative cross-sectional case study design over 3 months. We used thematic analysis with the framework approach of parent and provider interviews. Five team members individually coded transcripts and then met to discuss memos, update a construct summary sheet, and identify emerging themes. The team adapted themes into "How Might We" statements. For the ideation phase, multidisciplinary stakeholders brainstormed solutions to the "How Might We" statements in a design workshop. Workshop findings informed the design of a nurse-to-family telehealth intervention, which was iteratively revised over 2 months based on stakeholder feedback sessions. Results: We conducted interviews with nine parents, 11 nurses, and 13 physicians. Four themes emerged supporting the promise of a nurse-to-family telehealth intervention, the need to effectively communicate the intervention purpose, the value of a user-friendly workflow, and the essentiality of ensuring that diverse populations equitably benefit from the intervention. "How Might We" statements were discussed among 22 total workshop participants. Iterative adaptations were made to the intervention until feedback from workshop participants and 67 other stakeholders supported no further improvements were needed. Conclusion: Human-centered design phases facilitated stakeholder engagement in developing a nurse-to-family telehealth intervention. This intervention will be tested in an implementation phase as a feasibility and pilot trial.

Two teosintes made modern maize.

The origins of maize were the topic of vigorous debate for nearly a century, but neither the current genetic model nor earlier archaeological models account for the totality of available data, and recent work has highlighted the potential contribution of a wild relative, Zea mays ssp. mexicana. Our population genetic analysis reveals that the origin of modern maize can be traced to an admixture between ancient maize and Zea mays ssp. mexicana in the highlands of Mexico some 4000 years after domestication began. We show that variation in admixture is a key component of maize diversity, both at individual loci and for additive genetic variation underlying agronomic traits. Our results clarify the origin of modern maize and raise new questions about the anthropogenic mechanisms underlying dispersal throughout the Americas.

Genetic continuity and change among the Indigenous peoples of California.

Before the colonial period, California harboured more language variation than all of Europe, and linguistic and archaeological analyses have led to many hypotheses to explain this diversity1. We report genome-wide data from 79 ancient individuals from California and 40 ancient individuals from Northern Mexico dating to 7,400-200 years before present (BP). Our analyses document long-term genetic continuity between people living on the Northern Channel Islands of California and the adjacent Santa Barbara mainland coast from 7,400 years BP to modern Chumash groups represented by individuals who lived around 200 years BP. The distinctive genetic lineages that characterize present-day and ancient people from Northwest Mexico increased in frequency in Southern and Central California by 5,200 years BP, providing evidence for northward migrations that are candidates for spreading Uto-Aztecan languages before the dispersal of maize agriculture from Mexico2-4. Individuals from Baja California share more alleles with the earliest individual from Central California in the dataset than with later individuals from Central California, potentially reflecting an earlier linguistic substrate, whose impact on local ancestry was diluted by later migrations from inland regions1,5. After 1,600 years BP, ancient individuals from the Channel Islands lived in communities with effective sizes similar to those in pre-agricultural Caribbean and Patagonia, and smaller than those on the California mainland and in sampled regions of Mexico.

GATA1 deletion in human pluripotent stem cells increases differentiation yield and maturity of neutrophils.

Human pluripotent stem cell (hPSC)-derived tissues can be used to model diseases in cell types that are challenging to harvest and study at-scale, such as neutrophils. Neutrophil dysregulation, specifically neutrophil extracellular trap (NET) formation, plays a critical role in the prognosis and progression of multiple diseases, including COVID-19. While hPSCs can generate limitless neutrophils (iNeutrophils) to study these processes, current differentiation protocols generate heterogeneous cultures of granulocytes and precursors. Here, we describe a method to improve iNeutrophil differentiations through the deletion of GATA1. GATA1 knockout (KO) iNeutrophils are nearly identical to primary neutrophils in form and function. Unlike wild-type iNeutrophils, GATA1 KO iNeutrophils generate NETs in response to the physiologic stimulant lipopolysaccharide, suggesting they are a more accurate model when performing NET inhibitor screens. Furthermore, through deletion of CYBB, we demonstrate that GATA1 KO iNeutrophils are a powerful tool in determining involvement of a given protein in NET formation.

Predatory behavior under monocular and binocular conditions in the semiterrestrial crab Neohelice granulata.

Introduction: Neohelice granulata crabs live in mudflats where they prey upon smaller crabs. Predatory behavior can be elicited in the laboratory by a dummy moving at ground level in an artificial arena. Previous research found that crabs do not use apparent dummy size nor its retinal speed as a criterion to initiate attacks, relying instead on actual size and distance to the target. To estimate the distance to an object on the ground, Neohelice could rely on angular declination below the horizon or, since they are broad-fronted with eye stalks far apart, on stereopsis. Unlike other animals, binocular vision does not widen the visual field of crabs since they already cover 360° monocularly. There exist nonetheless areas of the eye with increased resolution. Methods: We tested how predatory responses towards the dummy changed when animals' vision was monocular (one eye occluded by opaque black paint) compared to binocular. Results: Even though monocular crabs could still perform predatory behaviors, we found a steep reduction in the number of attacks. Predatory performance defined by the probability of completing the attacks and the success rate (the probability of making contact with the dummy once the attack was initiated) was impaired too. Monocular crabs tended to use frontal, ballistic jumps (lunge behavior) less, and the accuracy of those attacks was reduced. Monocular crabs used prey interception (moving toward the dummy while it approached the crab) more frequently, favoring attacks when the dummy was ipsilateral to the viewing eye. Instead, binocular crabs' responses were balanced in the right and left hemifields. Both groups mainly approached the dummy using the lateral field of view, securing speed of response. Conclusion: Although two eyes are not strictly necessary for eliciting predatory responses, binocularity is associated with more frequent and precise attacks.

Trans-Holocene Bayesian chronology for tree and field crop use from El Gigante rockshelter, Honduras.

El Gigante rockshelter in western Honduras provides a deeply stratified archaeological record of human-environment interaction spanning the entirety of the Holocene. Botanical materials are remarkably well preserved and include important tree (e.g., ciruela (Spondias), avocado (Persea americana)) and field (maize (Zea mays), beans (Phaseolus), and squash (Cucurbita)) crops. Here we provide a major update to the chronology of tree and field crop use evident in the sequence. We report 375 radiocarbon dates, a majority of which are for short-lived botanical macrofossils (e.g., maize cobs, avocado seeds, or rinds). Radiocarbon dates were used in combination with stratigraphic details to establish a Bayesian chronology for ~9,800 identified botanical samples spanning the last 11,000 years. We estimate that at least 16 discrete intervals of use occurred during this time, separated by gaps of ~100-2,000 years. The longest hiatus in rockshelter occupation was between ~6,400 and 4,400 years ago and the deposition of botanical remains peaked at ~2,000 calendar years before present (cal BP). Tree fruits and squash appeared early in the occupational sequence (~11,000 cal BP) with most other field crops appearing later in time (e.g., maize at ~4,400 cal BP; beans at ~2,200 cal BP). The early focus on tree fruits and squash is consistent with early coevolutionary partnering with humans as seed dispersers in the wake of megafaunal extinction in Mesoamerica. Tree crops predominated through much of the Holocene, and there was an overall shift to field crops after 4,000 cal BP that was largely driven by increased reliance on maize farming.

Nurse-to-family telehealth for pediatric transfers: protocol for a feasibility and pilot cluster randomized controlled trial.

BACKGROUND: Children presenting to emergency departments of community hospitals may require transfer to a children's hospital for more definitive care, but the transfer process can be distressing and burdensome to patients, families, and the healthcare system. Using telehealth to bring the children's hospital nurse virtually to the bedside of the child in the emergency department has the potential to promote family-centered care and minimize triage issues and other transfer-associated burdens. To explore the feasibility of the nurse-to-family telehealth intervention, we are conducting a pilot study. METHODS: This parallel cluster randomized controlled feasibility and pilot trial will randomize six community emergency departments to use either nurse-to-family telehealth (intervention) or usual care (control) for pediatric inter-facility transfers. All eligible children presenting to a participating site during the study period who require inter-facility transfer will be included. Eligibility requires that there be an English-speaking adult parent or guardian at the emergency department bedside. We will examine feasibility objectives that assess protocol assignment adherence, fidelity, and survey response rates. We will measure subject-level exploratory outcome data to test feasibility of data collection and to obtain effect size estimates; exploratory outcomes include family-centered care, family experience, parent acute stress, parent distress, and change in level of care. Additionally, we will conduct a mixed methods implementation evaluation using the RE-AIM (Reach, Effectiveness, Adoption, Implementation, Maintenance) framework. DISCUSSION: The findings from this trial will increase our understanding about nurse-to-family telehealth during pediatric transfers. The mixed methods implementation evaluation will provide relevant insight about the contextual factors that influence the implementation and rigorous evaluation of our intervention. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT05593900. First Posted: October 26, 2022. Last Update Posted: December 5, 2022.

Clinical, microbiological, and genomic characteristics of clade-III Candida auris colonization and infection in southern California, 2019-2022.

BACKGROUND: Candida auris is an emerging fungal pathogen causing outbreaks in healthcare facilities. Five distinctive genomic clades exhibit clade-unique characteristics, highlighting the importance of real-time genomic surveillance and incorporating genotypic information to inform infection prevention practices and treatment algorithms. METHODS: Both active and passive surveillance were used to screen hospitalized patients. C. auris polymerase chain reaction (PCR) assay on inguinal-axillary swabs was performed on high-risk patients upon admission. All clinical yeast isolates were identified to the species level. C. auris isolates were characterized by both phenotypic antifungal susceptibility tests and whole-genome sequencing. RESULTS: From late 2019 to early 2022, we identified 45 patients with C. auris. Most had a tracheostomy or were from a facility with a known outbreak. Moreover, 7 patients (15%) were only identified through passive surveillance. Also, 8 (18%) of the patients had a history of severe COVID-19. The overall mortality was 18%. Invasive C. auris infections were identified in 13 patients (29%), 9 (69%) of whom had bloodstream infections. Patients with invasive infection were more likely to have a central line. All C. auris isolates were resistant to fluconazole but susceptible to echinocandins. Genomic analysis showed that 1 dominant clade-III lineage is circulating in Los Angeles, with very limited intrahost and interhost genetic diversity. CONCLUSIONS: We have demonstrated that a robust C. auris surveillance program can be established using both active and passive surveillance, with multidisciplinary efforts involving the microbiology laboratory and the hospital epidemiology team. In Los Angeles County, C. auris strains are highly related and echinocandins should be used for empiric therapy.

Drought-Induced Civil Conflict Among the Ancient Maya.

The influence of climate change on civil conflict and societal instability in the premodern world is a subject of much debate, in part because of the limited temporal or disciplinary scope of case studies. We present a transdisciplinary case study that combines archeological, historical, and paleoclimate datasets to explore the dynamic, shifting relationships among climate change, civil conflict, and political collapse at Mayapan, the largest Postclassic Maya capital of the Yucatán Peninsula in the thirteenth and fourteenth centuries CE. Multiple data sources indicate that civil conflict increased significantly and generalized linear modeling correlates strife in the city with drought conditions between 1400 and 1450 cal. CE. We argue that prolonged drought escalated rival factional tensions, but subsequent adaptations reveal regional-scale resiliency, ensuring that Maya political and economic structures endured until European contact in the early sixteenth century CE.

Genomes from Verteba cave suggest diversity within the Trypillians in Ukraine.

The transition to agriculture occurred relatively late in Eastern Europe, leading researchers to debate whether it was a gradual, interactive process or a colonisation event. In the forest and forest-steppe regions of Ukraine, farming appeared during the fifth millennium BCE, associated with the Cucuteni-Trypillia cultural complex (CTCC, ~ 5000-3000 BCE). Across Europe, the Neolithisation process was highly variable across space and over time. Here, we investigate the population dynamics of early agriculturalists from the eastern forest-steppe region based on the analyses of 20 ancient genomes from the site of Verteba Cave (3935-825 cal BCE). Results reveal that the CTCC individuals' ancestry is related to both western hunter-gatherers and Near Eastern farmers, has no local ancestry associated with Ukrainian Neolithic hunter-gatherers and has steppe ancestry. An Early Bronze Age individual has an ancestry profile related to the Yamnaya expansions but with 20% of ancestry related to the other Trypillian individuals, which suggests admixture between the Trypillians and the incoming populations carrying steppe-related ancestry. A Late Bronze Age individual dated to 980-825 cal BCE has a genetic profile indicating affinity to Beaker-related populations, detected close to 1000 years after the end of the Bell Beaker phenomenon during the third millennium BCE.

South-to-north migration preceded the advent of intensive farming in the Maya region.

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.

Shoulder Synovitis Does not Affect Pain After Arthroscopic Rotator Cuff Repair.

Background: The goal of this study was to determine if there is an association between glenohumeral synovitis and early post-operative pain after arthroscopic rotator cuff repair. Methods: Fifty patients with symptomatic rotator cuff tears were prospectively enrolled prior to RCR. Baseline ASES score, VAS Pain score, forward elevation, and external rotation were recorded. Intra-operatively, synovitis was graded on a scale of zero to six as based on a previously validated scoring system. VAS Pain scores were obtained from patients post-operatively on days one through 14, week 6, and 3 months. Results: Average intra-operative synovitis score was 2.4 ± 1.6. No significant correlation was found between synovitis score and pre-operative forward elevation (P=0.171), external rotation (P=0.126), VAS Pain (P=0.623), or ASES (P=0.187) scores. No significant correlation was found between synovitis score and post-operative VAS Pain level at any time point. There was a moderate correlation between both pre-operative VAS Pain and ASES scores and post-operative VAS Pain in the first post-operative week. Workers' compensation patients had worse pain at 3 months post-operatively compared to non-workers compensation patients (P=0.038). Conclusion: This study reveals that macroscopically assessed glenohumeral synovitis does not have any significant correlation with pre-operative or post-operative pain in patients undergoing arthroscopic rotator cuff repair; although higher pre-operative pain levels, worse pre-operative ASES scores, and workers compensation status do influence post-operative pain levels in arthroscopic rotator cuff repair.

Outcomes of chronic distal biceps reconstruction with tendon grafting: a matched comparison with primary repair.

BACKGROUND: The purpose of this analysis was to analyze outcomes of distal biceps reconstruction with soft tissue allograft in the setting of chronic, irreparable distal biceps ruptures. The outcomes of these cases were then compared with a matched cohort of distal biceps ruptures that were able to be repaired primarily. METHODS: Retrospective review of an institutional elbow surgery database was conducted. All cases of distal biceps repairs were identified by Common Procedural Terminology, ICD-9, and ICD-10 codes from January 2009 to March 2018. A direct review of operative reports was then conducted to identify which cases required allograft reconstruction. After identification of this population, a 2:1 manually matched cohort of patients who underwent primary repair was generated using age, gender, body mass index, and age-adjusted Charlson Comorbidity Index. Finally, the allograft reconstruction and matched primary repair cohorts were compared for reoperation, range of motion, and patient-reported outcomes scores. RESULTS: There were 46 male patients who underwent distal biceps reconstruction with allograft (14 Achilles tendon, 32 semitendinosus) and they were matched to 92 male patients that underwent primary distal biceps repair. Mean patient age (46.9 ± 10.3 vs. 47.0 ± 9.8 years, P = .95), BMI (31.3 ± 5.3 vs. 31.3 ± 4.8 kg/m2, P = .60), and Charlson Comorbidity Index (1.2 ± 1.1 vs. 1.3 ± 0.9, P = .64) were similar between allograft reconstruction and primary repair groups. Disability of the Arm, Shoulder and Hand score (7.4 ± 18.0 vs. 1.6 ± 4.1, P = .23), Mayo Elbow Performance Score (92.1 ± 19.7 vs. 97.3 ± 6.4, P = .36), and Oxford Elbow Score (43.4 ± 11.0 vs. 46.8 ± 3.2, P = .25) were not significantly different between groups at mean 5.1 years (range, 1.5-10.9 years) after surgery. There were 1 of 42 (2.2%) allograft patients who require revision compared with 3 of 92 (3.3%, P = .719) in the primary repair group. In addition, one primary repair required reoperation for scar tissue excision and lateral antebrachial cutaneous neurolysis. Final range of motion data (twelve-week follow-up) for the allograft reconstruction group was similar to primary repair group in flexion (136.1° ± 5.3° vs. 135.9° ± 2.7°, P = .81), extension (0.8° ± 2.9° vs. 0.4° ± 1.7°, P = .53), pronation (78.0° ± 9.0° vs. 76.4° ± 15.4°, P = .50), supination (77.4° ± 10.7° vs. 77.5° ± 11.9°, P = .96). CONCLUSION: Patients who underwent distal biceps reconstruction with a graft had similar failure rates, reoperation rates, final range of motion, and patient-reported outcomes scores as those treated without a graft. Patients can be consulted that direct repair in the acute setting is preferred; however, even in the setting of a distal biceps reconstruction with graft augmentation, they can expect low complications and good functional results.

Effect of perioperative acetaminophen on pain management in patients undergoing rotator cuff repair: a prospective randomized study.

BACKGROUND: Limiting opioid use in perioperative pain management is currently an important focus in orthopedic surgery. The ability of acetaminophen to reduce postoperative opioid consumption while providing acceptable pain management has not been thoroughly investigated in patients undergoing rotator cuff repair (RCR). METHODS: Patients undergoing primary arthroscopic RCR were prospectively randomized to 1 of 3 treatment groups: Group 1 (control) received both 5 mg of oxycodone every 6 hours as needed and 1000 mg of acetaminophen orally every 6 hours as needed after surgery and had the option to take either medication or both. Group 2 (control) received only 5 mg of oxycodone every 6 hours as needed without any additional acetaminophen after surgery. Group 3 received 1000 mg of acetaminophen orally every 6 hours for 1 day prior to and after surgery, which was subsequently decreased to administration every 8 hours during postoperative days 2-5. Group 3 patients were also allowed to take 5 mg of oxycodone every 6 hours as needed after surgery. All patients received interscalene blocks with liposomal bupivacaine (Exparel). Opioid use, pain scores, side effects, and overall satisfaction were assessed daily for the first week after surgery. RESULTS: A total of 57 patients (mean age, 57.8 ± 9.55 years) were included in this study. Baseline demographic characteristics including age, sex, and body mass index were similar between the groups (P > .05). Patients in group 3 took significantly fewer narcotics overall (P = .017) and took significantly fewer pills each day compared with group 2. Group 3 also reported significantly better overall pain control compared with the other groups (P = .040). There were no significant differences in overall patient satisfaction between the groups (P > .05). Additionally, there were no significant differences between groups regarding postoperative medication-associated side effects (P > .05). CONCLUSION: Perioperative acetaminophen represents an important component of multimodal analgesia in appropriately selected patients undergoing shoulder surgery. In this study, the use of perioperative acetaminophen significantly decreased opioid consumption and improved overall pain control after primary arthroscopic RCR.

Early postoperative complications after Latarjet procedure: a single-institution experience over 10 years.

BACKGROUND: The Latarjet procedure is an effective procedure for the treatment of anterior glenohumeral joint instability; however, the complications are concerning. The purpose of this study was to review a single institution's experience with the Latarjet procedure for recurrent anterior glenohumeral instability specifically focusing on early complications. METHODS: This was a retrospective review of all Latarjet procedures performed at a single institution from August 2008 to July 2018. The 90-day complication rate and associated risk factors for all complications and graft failure were recorded. Postoperative radiographs were reviewed for coracoid graft position and screw divergence. RESULTS: During the study period, 190 Latarjet procedures were performed with 90-day follow-up. The average age was 28.7 ± 11.3 years, male patients comprised 84.2% of the population, and 62.6% of patients had undergone a prior stabilization procedure. We observed 15 complications, for a 90-day complication rate of 9.0%; of the patients, 8 (4.2%) underwent reoperations. Graft or hardware failure occurred in 9 patients (4.7%) with loosened or broken screws, and 6 required reoperations (revision Latarjet procedure in 4, distal tibia allograft in 1, and iliac crest autograft in 1). Fixation with only 1 screw (P < .001) and an increased screw divergence angle (37° ± 8° vs. 24° ± 11°, P = .0257) were statistically associated with graft failure, whereas the use of cannulated screws (P = .487) was not. There were 6 nerve injuries (3.2%), including 2 combined axillary and suprascapular nerve injuries, 1 musculocutaneous nerve injury, 1 brachial plexopathy, 1 peripheral sensory nerve deficit (likely axillary), and 1 sensory plexopathy. Suprascapular nerve injury at the spinoglenoid notch was associated with a longer superior screw (41.0 ± 1.4 mm vs. 33.5 ± 3.5 mm, P = .035) and increased screw divergence angle (40° ± 6° vs. 24° ± 11°, P = .0197). The coracoid graft was correctly positioned in the axial plane in 71% of cases and in the coronal plane in 73% of cases. CONCLUSION: The Latarjet procedure is a procedure that can reliably restore shoulder stability; however, graft- and nerve-related complications are relatively common. Two-thirds of the graft failures required reoperations, and half of the nerve injuries in this study led to residual symptoms. Fixation with only 1 screw and an increased screw divergence angle were significant predictors of graft failure. Suprascapular nerve injury at the spinoglenoid notch was associated with an increased screw divergence angle and longer superior screw.

Archaeological Central American maize genomes suggest ancient gene flow from South America.

Maize (Zea mays ssp. mays) domestication began in southwestern Mexico ∼9,000 calendar years before present (cal. BP) and humans dispersed this important grain to South America by at least 7,000 cal. BP as a partial domesticate. South America served as a secondary improvement center where the domestication syndrome became fixed and new lineages emerged in parallel with similar processes in Mesoamerica. Later, Indigenous cultivators carried a second major wave of maize southward from Mesoamerica, but it has been unclear until now whether the deeply divergent maize lineages underwent any subsequent gene flow between these regions. Here we report ancient maize genomes (2,300-1,900 cal. BP) from El Gigante rock shelter, Honduras, that are closely related to ancient and modern maize from South America. Our findings suggest that the second wave of maize brought into South America hybridized with long-established landraces from the first wave, and that some of the resulting newly admixed lineages were then reintroduced to Central America. Direct radiocarbon dates and cob morphological data from the rock shelter suggest that more productive maize varieties developed between 4,300 and 2,500 cal. BP. We hypothesize that the influx of maize from South America into Central America may have been an important source of genetic diversity as maize was becoming a staple grain in Central and Mesoamerica.

Ancient genomes in South Patagonia reveal population movements associated with technological shifts and geography.

Archaeological research documents major technological shifts among people who have lived in the southern tip of South America (South Patagonia) during the last thirteen millennia, including the development of marine-based economies and changes in tools and raw materials. It has been proposed that movements of people spreading culture and technology propelled some of these shifts, but these hypotheses have not been tested with ancient DNA. Here we report genome-wide data from 20 ancient individuals, and co-analyze it with previously reported data. We reveal that immigration does not explain the appearance of marine adaptations in South Patagonia. We describe partial genetic continuity since ~6600 BP and two later gene flows correlated with technological changes: one between 4700-2000 BP that affected primarily marine-based groups, and a later one impacting all <2000 BP groups. From ~2200-1200 BP, mixture among neighbors resulted in a cline correlated to geographic ordering along the coast.

Integration of ancient DNA with transdisciplinary dataset finds strong support for Inca resettlement in the south Peruvian coast.

Ancient DNA (aDNA) analysis provides a powerful means of investigating human migration, social organization, and a plethora of other crucial questions about humanity's past. Recently, specialists have suggested that the ideal research design involving aDNA would include multiple independent lines of evidence. In this paper, we adopt a transdisciplinary approach integrating aDNA with archaeological, biogeochemical, and historical data to investigate six individuals found in two cemeteries that date to the Late Horizon (1400 to 1532 CE) and Colonial (1532 to 1825 CE) periods in the Chincha Valley of southern Peru. Genomic analyses indicate that these individuals are genetically most similar to ancient and present-day populations from the north Peruvian coast located several hundred kilometers away. These genomic data are consistent with 16th century written records as well as ceramic, textile, and isotopic data. These results provide some of the strongest evidence yet of state-sponsored resettlement in the pre-Colonial Andes. This study highlights the power of transdisciplinary research designs when using aDNA data and sets a methodological standard for investigating ancient mobility in complex societies.

Early isotopic evidence for maize as a staple grain in the Americas.

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.