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Nuclear mitochondrial pseudogenes (numts) may hinder the reconstruction of mtDNA genomes and affect the reliability of mtDNA datasets for phylogenetic and population genetic comparisons. Here, we present the program Numt Parser, which allows for the identification of DNA sequences that likely originate from numt pseudogene DNA. Sequencing reads are classified as originating from either numt or true cytoplasmic mitochondrial (cymt) DNA by direct comparison against cymt and numt reference sequences. Classified reads can then be parsed into cymt or numt datasets. We tested this program using whole genome shotgun-sequenced data from two ancient Cape lions (Panthera leo), because mtDNA is often the marker of choice for ancient DNA studies and the genus Panthera is known to have numt pseudogenes. Numt Parser decreased sequence disagreements that were likely due to numt pseudogene contamination and equalized read coverage across the mitogenome by removing reads that likely originated from numts. We compared the efficacy of Numt Parser to two other bioinformatic approaches that can be used to account for numt contamination. We found that Numt Parser outperformed approaches that rely only on read alignment or Basic Local Alignment Search Tool (BLAST) properties, and was effective at identifying sequences that likely originated from numts while having minimal impacts on the recovery of cymt reads. Numt Parser therefore improves the reconstruction of true mitogenomes, allowing for more accurate and robust biological inferences.

The ethics of the scientific study of Ancestors has long been debated by archaeologists, bioanthropologists, and, more recently, ancient DNA (aDNA) researchers. This article responds to the article “Ethics of DNA research on human remains: five globally applicable guidelines” published in 2021 in Nature by a large group of aDNA researchers and collaborators. We argue that these guidelines do not sufficiently consider the interests of community stakeholders, including descendant communities and communities with potential, but yet unestablished, ties to Ancestors. We focus on three main areas of concern with the guidelines. First is the false separation of “scientific” and “community” concerns and the consistent privileging of researcher perspectives over those of community members. Second, the commitment of the guidelines’ authors to open data ignores the principles and practice of Indigenous Data Sovereignty. Further, the authors argue that involving community members in decisions about publication and data sharing is unethical. We argue that excluding community perspectives on “ethical” grounds is convenient for researchers, but it is not, in fact, ethical. Third, we stress the risks of not consulting communities that have established or potential ties to Ancestors, using two recent examples from the literature. Ancient DNA researchers cannot focus on the lowest common denominator of research practice, the bare minimum that is legally necessary. Instead, they should be leading multidisciplinary efforts to create processes to ensure communities from all regions of the globe are identified and engaged in research that affects them. This will often present challenges, but we see these challenges as part of the research, rather than a distraction from the scientific endeavor. If a research team does not have the capacity to meaningfully engage communities, questions must be asked about the value and benefit of their research.

Objectives Long‐tailed macaques (Macaca fascicularis) are widely distributed throughout the mainland and islands of Southeast Asia, making them a useful model for understanding the complex biogeographical history resulting from drastic changes in sea levels throughout the Pleistocene. Past studies based on mitochondrial genomes (mitogenomes) of long‐tailed macaque museum specimens have traced their colonization patterns throughout the archipelago, but mitogenomes trace only the maternal history. Here, our objectives were to trace phylogeographic patterns of long‐tailed macaques using low‐coverage nuclear DNA (nDNA) data from museum specimens. Methods We performed population genetic analyses and phylogenetic reconstruction on nuclear single nucleotide polymorphisms (SNPs) from shotgun sequencing of 75 long‐tailed macaque museum specimens from localities throughout Southeast Asia. Results We show that shotgun sequencing of museum specimens yields sufficient genome coverage (average ~1.7%) for reconstructing population relationships using SNP data. Contrary to expectations of divergent results between nuclear and mitochondrial genomes for a female philopatric species, phylogeographical patterns based on nuclear SNPs proved to be closely similar to those found using mitogenomes. In particular, population genetic analyses and phylogenetic reconstruction from the nDNA identify two major clades within M. fascicularis: Clade A includes all individuals from the mainland along with individuals from northern Sumatra, while Clade B consists of the remaining island‐living individuals, including those from southern Sumatra. Conclusions Overall, we demonstrate that low‐coverage sequencing of nDNA from museum specimens provides enough data for examining broad phylogeographic patterns, although greater genome coverage and sequencing depth would be needed to distinguish between very closely related populations, such as those throughout the Philippines.

Addressing Indigenous rights and interests in genetic resources has become increasingly challenging in an open science environment that promotes unrestricted access to genomic data. Although Indigenous experiences with genetic research have been shaped by a series of negative interactions, there is increasing recognition that equitable benefits can only be realized through greater participation of Indigenous communities. Issues of trust, accountability and equity underpin Indigenous critiques of genetic research and the sharing of genomic data. This Perspectives article highlights identified issues for Indigenous communities around the sharing of genomic data and suggests principles and actions that genomic researchers can adopt to recognize community rights and interests in data.

Significance California supports a high cultural and linguistic diversity of Indigenous peoples. In a partnership of researchers with the Muwekma Ohlone tribe, we studied genomes of eight present-day tribal members and 12 ancient individuals from two archaeological sites in the San Francisco Bay Area, spanning ∼2,000 y. We find that compared to genomes of Indigenous individuals from throughout the Americas, the 12 ancient individuals are most genetically similar to ancient individuals from Southern California, and that despite spanning a large time period, they share distinctive ancestry. This ancestry is also shared with present-day tribal members, providing evidence of genetic continuity between past and present Indigenous individuals in the region, in contrast to some popular reconstructions based on archaeological and linguistic information.

Modern humans carry Neanderthal and Denisovan (archaic) genome elements which may have been adaptive. These effects may be particularly evident in pharmacogenes - genes responsible for the processing of exogenous substances such as food, pollutants, and medications. However, the health implications and contribution of archaic ancestry in pharmacogenes of modern humans remains understudied. We characterize eleven key cytochrome P450 (CYP450) genes involved in drug metabolizing reactions in three Neanderthal and one Denisovan individuals and examine archaic introgression in modern human populations. We infer the metabolizing efficiency of these eleven genes in archaic individuals and show important genetic differences relative to modern human variants. We identify archaic-specific SNVs in each CYP450 gene, including some that are potentially damaging, which may result in altered metabolism in modern human people carrying these variants. We highlight four genes which display interesting patterns of archaic variation: CYP2B6 - we find a large number of unique variants in the Vindija Neanderthal, some of which are shared with a small subset of African modern humans; CYP2C9 - containing multiple variants that are shared between Europeans and Neanderthals; CYP2A6*12 - a variant defined by a hybridization event that was found in humans and Neanderthals, suggesting the recombination event predates both species; and CYP2J2 - in which we hypothesize a Neanderthal variant was re-introduced in non-African populations by archaic admixture. The genetic variation identified in archaic individuals suggests that selective pressures from the environment may be involved in the evolution of CYP450 genes.

The ‘social microbiome’ can fundamentally shape the costs and benefits of group-living, but understanding social transmission of microbes in free-living animals is challenging due to confounding effects of kinship and shared environments (e.g. highly associated individuals often share the same spaces, food and water). Here, we report evidence for convergence towards a social microbiome among introduced common vampire bats,Desmodus rotundus, a highly social species in which adults feed only on blood, and engage in both mouth-to-body allogrooming and mouth-to-mouth regurgitated food sharing. Shotgun sequencing of samples from six zoos in the USA, 15 wild-caught bats from a colony in Belize and 31 bats from three colonies in Panama showed that faecal microbiomes were more similar within colonies than between colonies. To assess microbial transmission, we created an experimentally merged group of the Panama bats from the three distant sites by housing these bats together for four months. In this merged colony, we found evidence that dyadic gut microbiome similarity increased with both clustering and oral contact, leading to microbiome convergence among introduced bats. Our findings demonstrate that social interactions shape microbiome similarity even when controlling for past social history, kinship, environment and diet.

Archaeologists often struggle with the challenge of linking historic-period artifact assemblages with specific communities. In particular, small home sites discovered on historic plantations are often difficult to identify as an African American or white tenant house since the material culture appears similar. The discipline also struggles with how to identify the expression of specific West African cultures in their archaeological assemblages. Here, we discuss how DNA was successfully extracted and analyzed from a clay tobacco pipe stem collected from an African American slave quarter in Maryland, USA, and what this information can and cannot reveal about the people present at the site. We successfully identified DNA from a woman, and genome-wide analyses revealed she was closely related to Mende living in present-day Sierra Leone, West Africa. The ability to recover genetic data from personal artifacts now provides archaeologists a viable tool to address questions about communities and ancestral origins. Furthermore, these findings hold the potential to connect living descendants with their ancestors’ homes.

Advances in the isolation and sequencing of ancient DNA have begun to reveal the population histories of both people and dogs. Over the last 10,000 y, the genetic signatures of ancient dog remains have been linked with known human dispersals in regions such as the Arctic and the remote Pacific. It is suspected, however, that this relationship has a much deeper antiquity, and that the tandem movement of people and dogs may have begun soon after the domestication of the dog from a gray wolf ancestor in the late Pleistocene. Here, by comparing population genetic results of humans and dogs from Siberia, Beringia, and North America, we show that there is a close correlation in the movement and divergences of their respective lineages. This evidence places constraints on when and where dog domestication took place. Most significantly, it suggests that dogs were domesticated in Siberia by ∼23,000 y ago, possibly while both people and wolves were isolated during the harsh climate of the Last Glacial Maximum. Dogs then accompanied the first people into the Americas and traveled with them as humans rapidly dispersed into the continent beginning ∼15,000 y ago.

Summary The recently enriched genomic history of Indigenous groups in the Americas is still meager concerning continental Central America. Here, we report ten pre-Hispanic (plus two early colonial) genomes and 84 genome-wide profiles from seven groups presently living in Panama. Our analyses reveal that pre-Hispanic demographic events contributed to the extensive genetic structure currently seen in the area, which is also characterized by a distinctive Isthmo-Colombian Indigenous component. This component drives these populations on a specific variability axis and derives from the local admixture of different ancestries of northern North American origin(s). Two of these ancestries were differentially associated to Pleistocene Indigenous groups that also moved into South America, leaving heterogenous genetic footprints. An additional Pleistocene ancestry was brought by a still unsampled population of the Isthmus (UPopI) that remained restricted to the Isthmian area, expanded locally during the early Holocene, and left genomic traces up to the present day., Graphical abstract, Highlights • Ancient Isthmian genomes address anthropological questions on pre-contact burials • The comparison with modern Panamanians highlights genomic structure on the Isthmus • A genomic component drives the Isthmian groups on a distinctive variability axis • A previously unknown Pleistocene ancestry identified in the Isthmo-Colombian area, Pre-contact and modern genomes from Panama highlight the distinctiveness of the Isthmo-Colombian area; detail number, source, and impact of Indigenous American genomic ancestries at the continental level; and explain complex pre-Hispanic burials.

Summary The oldest known shipwreck in southern Africa was found in Namibia in 2008. 1 , 2 , 3 , 4 Forty tons of cargo, including gold and silver coins, helped identify the ship as the Bom Jesus, a Portuguese nau (trading vessel) lost in 1533 while headed to India. 4 , 5 , 6 The cargo included >100 elephant tusks, 7 which we examined using paleogenomic and stable isotope analyses. Nuclear DNA identified the ivory source as African forest (Loxodonta cyclotis) rather than savanna (Loxodonta africana) elephants. Mitochondrial sequences traced them to West and not Central Africa and from ≥17 herds with distinct haplotypes. Four of the haplotypes are known from modern populations; others were potentially lost to subsequent hunting of elephants for ivory. Stable isotope analyses (δ13C and δ15N) indicated that the elephants were not from deep rainforests but from savanna and mixed habitats. Such habitats surround the Guinean forest block of West Africa 8 and accord with the locations of major historic Portuguese trading ports. 9 , 10 West African forest elephants currently range into savanna habitats; 11 , 12 , 13 our findings suggest that this was not consequent to regional decimation of savanna elephants for their ivory in the 19th and 20th centuries. During the time of the Bom Jesus, ivory was a central driver in the formation of maritime trading systems connecting Europe, Africa, and Asia. Our integration of paleogenomic, archeological, and historical methods to analyze the Bom Jesus ivory provides a framework for examining vast collections of archaeological ivories around the world, in shipwrecks and other contexts.

Significance Based on “subfossil” skeletal remains it is known that multiple now-extinct giant lemur (primate) species with estimated body masses of up to ∼160 kg survived on Madagascar into the past millennium. In this study, we used ancient DNA methods to sequence the nuclear genome of one of these megafaunal lemurs, Megaladapis edwardsi (∼85 kg). With the power of the nuclear genome, we robustly resolved the phylogenetic relationship between Megaladapis and other lemurs, which had been a lingering uncertainty. We also identified multiple signatures of past positive natural selection across the M. edwardsi genome that support reconstructions of this taxon as a large-bodied, specialized folivore., No endemic Madagascar animal with body mass >10 kg survived a relatively recent wave of extinction on the island. From morphological and isotopic analyses of skeletal “subfossil” remains we can reconstruct some of the biology and behavioral ecology of giant lemurs (primates; up to ∼160 kg) and other extraordinary Malagasy megafauna that survived into the past millennium. Yet, much about the evolutionary biology of these now-extinct species remains unknown, along with persistent phylogenetic uncertainty in some cases. Thankfully, despite the challenges of DNA preservation in tropical and subtropical environments, technical advances have enabled the recovery of ancient DNA from some Malagasy subfossil specimens. Here, we present a nuclear genome sequence (∼2× coverage) for one of the largest extinct lemurs, the koala lemur Megaladapis edwardsi (∼85 kg). To support the testing of key phylogenetic and evolutionary hypotheses, we also generated high-coverage nuclear genomes for two extant lemurs, Eulemur rufifrons and Lepilemur mustelinus, and we aligned these sequences with previously published genomes for three other extant lemurs and 47 nonlemur vertebrates. Our phylogenetic results confirm that Megaladapis is most closely related to the extant Lemuridae (typified in our analysis by E. rufifrons) to the exclusion of L. mustelinus, which contradicts morphology-based phylogenies. Our evolutionary analyses identified significant convergent evolution between M. edwardsi and an extant folivore (a colobine monkey) and an herbivore (horse) in genes encoding proteins that function in plant toxin biodegradation and nutrient absorption. These results suggest that koala lemurs were highly adapted to a leaf-based diet, which may also explain their convergent craniodental morphology with the small-bodied folivore Lepilemur.

Sex estimation of skeletons is fundamental to many archaeological studies. Currently, three approaches are available to estimate sex–osteology, genomics, or proteomics, but little is known about the relative reliability of these methods in applied settings. We present matching osteological, shotgun-genomic, and proteomic data to estimate the sex of 55 individuals, each with an independent radiocarbon date between 2,440 and 100 cal BP, from two ancestral Ohlone sites in Central California. Sex estimation was possible in 100% of this burial sample using proteomics, in 91% using genomics, and in 51% using osteology. Agreement between the methods was high, however conflicts did occur. Genomic sex estimates were 100% consistent with proteomic and osteological estimates when DNA reads were above 100,000 total sequences. However, more than half the samples had DNA read numbers below this threshold, producing high rates of conflict with osteological and proteomic data where nine out of twenty conditional DNA sex estimates conflicted with proteomics. While the DNA signal decreased by an order of magnitude in the older burial samples, there was no decrease in proteomic signal. We conclude that proteomics provides an important complement to osteological and shotgun-genomic sex estimation.

Addressing Indigenous rights and interests in genetic resources has become increasingly challenging in an open science environment that promotes unrestricted access to genomic data. Although Indigenous experiences with genetic research have been shaped by a series of negative interactions, there is increasing recognition that equitable benefits can only be realized through greater participation of Indigenous communities. Issues of trust, accountability and equity underpin Indigenous critiques of genetic research and the sharing of genomic data. This Perspectives article highlights identified issues for Indigenous communities around the sharing of genomic data and suggests principles and actions that genomic researchers can adopt to recognize community rights and interests in data.

The genomic histories of Indigenous groups in the Americas have been recently enriched by modern and ancient data, but the dataset on continental Central America is still meagre. Here, we report ten ancient pre-Hispanic (plus two early colonial) genomes and 84 genome-wide profiles from seven groups presently living in Panama, on the Isthmian land-bridge connecting North and South America. Our analysis reveals extensive sub-structure in the geographic area with pre-colonial Panamanians clustering separately. On a continental scale, the Isthmian populations are distinguished by a previously unknown Indigenous component in the Americas. This component derives from the admixture of different early Indigenous groups that originated from the same northern North American source in the late Pleistocene. The earlier population(s) moved further south, leaving differential footprints in South America, while another group remained restricted to the Isthmo-Colombian area, expanded locally during the early Holocene and left genomic traces up to now.

Lineage losses for man's best friend Dogs have been present in North America for at least 9000 years. To better understand how present-day breeds and populations reflect their introduction to the New World, Ní Leathlobhair et al. sequenced the mitochondrial and nuclear genomes of ancient dogs (see the Perspective by Goodman and Karlsson). The earliest New World dogs were not domesticated from North American wolves but likely originated from a Siberian ancestor. Furthermore, these lineages date back to a common ancestor that coincides with the first human migrations across Beringia. This lineage appears to have been mostly replaced by dogs introduced by Europeans, with the primary extant lineage remaining as a canine transmissible venereal tumor. Science , this issue p. 81 ; see also p. 27

The Sumatran rhinoceros (Dicerorhinus sumatrensis), once widespread across Southeast Asia, now consists of as few as 30 individuals within Sumatra and Borneo. To aid in conservation planning, we sequenced 218 bp of control region mitochondrial (mt) DNA, identifying 17 distinct mitochondrial haplotypes across modern (N = 13) and museum (N = 26) samples. Museum specimens from Laos and Myanmar had divergent mtDNA, consistent with the placement of western mainland rhinos into the distinct subspecies D. s. lasiotis (presumed extinct). Haplotypes from Bornean rhinos were highly diverse, but dissimilar from those of other regions, supporting the distinctiveness of the subspecies D. s. harrissoni. Rhinos from Sumatra and Peninsular Malaysia shared mtDNA haplotypes, consistent with their traditional placement into a single subspecies D. s sumatrensis. Modern samples of D. s. sumatrensis were genotyped at 18 microsatellite loci. Rhinos within Sumatra formed 2 sub-populations, likely separated by the Barisan Mountains, though with only modest genetic differentiation between them. There are so few remaining Sumatran rhinoceros that separate management strategies for subspecies or subpopulations may not be viable, while each surviving rhino pedigree is likely to retain alleles found in no other individuals. Given the low population size and low reproductive potential of Sumatran rhinos, rapid genetic erosion is inevitable, though an under-appreciated concern is the potential for fixation of harmful genetic variants. Both concerns underscore 2 overriding priorities for the species: 1) translocation of wild rhinos to ex situ facilities, and 2) collection and storage of gametes and cell lines from every surviving captive and wild individual.

Biological Anthropology studies the variation and evolution of living humans, non-human primates, and extinct ancestors and for this reason the field should be in an ideal position to attract scientists from a variety of backgrounds who have different views and experiences. However, the origin and history of the discipline, anecdotal observations, self-reports, and recent surveys suggest the field has significant barriers to attracting scholars of color. For a variety of reasons, including quantitative research that demonstrates that diverse groups do better science, the discipline should strive to achieve a more diverse composition. Here we discuss the background and underpinnings of the current and historical dearth of diversity in Biological Anthropology in the U.S. specifically as it relates to representation of minority and underrepresented minority (URM) (or racialized minority) scholars. We trace this lack of diversity to underlying issues of recruitment and retention in the STEM sciences generally, to the history of Anthropology particularly around questions of race-science, and to the absence of Anthropology at many minority-serving institutions, especially HBCUs, a situation that forestalls pathways to the discipline for many minority students. The AAPA Committee on Diversity (COD) was conceived as a means of assessing and improving diversity within the discipline, and we detail the history of the COD since its inception in 2006. Prior to the COD there were no systematic AAPA efforts to consider ethnoracial diversity in our ranks and no programming around questions of diversity and inclusion. Departmental survey data collected by the COD indicate that undergraduate majors in Biological Anthropology are remarkably diverse, but that the discipline loses these scholars between undergraduate and graduate school and systematically up rank. Our analysis of recent membership demographic survey data (2014 and 2017) shows Biological Anthropology to have less ethnoracial diversity than even the affiliated STEM disciplines of Biology and Anatomy; nearly 87% of AAPA members in the United States identify as white and just 7% as URM scholars. These data also suggest that the intersection of race and gender significantly influence scholarly representation. In response to these data, we describe a substantial body of programs that have been developed by the COD to improve diversity in our ranks. Through these programs we identify principal concerns that contribute to the loss of scholars of color from the discipline at different stages in their careers, propose other directions that programming for recruitment should take, and discuss the beginnings of how to develop a more inclusive discipline at all career stages.

Seven fish vertebrae were chosen for analysis from the 49-KEN-147 archaeological site in the Kenai Peninsula, Alaska. Mitochondrial DNA analysis of the ancient fish bones revealed that they were from sockeye and coho salmon. Here, we report the ancient mitochondrial genomes for three sockeye salmon and one coho salmon fish bone.

Automated, high-throughput technologies are becoming increasingly common in microbiome studies to decrease costs and increase efficiency. However, in microbiome studies, small differences in methodology – including storage conditions, wet lab methods, sequencing platforms and data analysis – can influence the reproducibility and comparability of data across studies. There has been limited testing of the effects of high-throughput methods, including microfluidic PCR technologies. In this paper, we compare two extraction methods (the QIAamp DNA Stool Mini Kit and the MoBio PowerSoil DNA Isolation kit), two taq polymerase enzymes (MyTaq HS Red Mix and Accustart II PCR ToughMix), two primer sets (V3–V4 and V4–V5) and two amplification methods (a common two-step PCR protocol and amplicon library preparation on the Fluidigm Access Array system that allows automated multiplexing of primers). Gut microbial community profiles were significantly affected by all variables. While there were no significant differences in alpha diversity measured between the two extraction methods, there was an effect of extraction method on community composition measured by unweighted UniFrac distances. Both amplification method and primers had a significant effect on both alpha diversity and community composition. The relative abundance of Actinobacteria was significantly lower when using the MoBio kit or Fluidigm amplification method, and the relative abundance of Firmicutes was lower when using the Qiagen kit. Microbial community profiles based on Fluidigm-generated amplicon libraries were not comparable to those generated with more commonly used methods. Researchers should carefully consider the limitations and biases that different extraction and amplification methods can introduce into their results. Additionally, more thorough benchmarking of automated and multiplexing methods is necessary to determine the magnitude of the potential trade-off between the quality and the quantity of data.

Northeastern Siberia has been inhabited by humans for more than 40,000 years but its deep population history remains poorly understood. Here we investigate the late Pleistocene population history of northeastern Siberia through analyses of 34 newly recovered ancient genomes that date to between 31,000 and 600 years ago. We document complex population dynamics during this period, including at least three major migration events: an initial peopling by a previously unknown Palaeolithic population of ‘Ancient North Siberians’ who are distantly related to early West Eurasian hunter-gatherers; the arrival of East Asian-related peoples, which gave rise to ‘Ancient Palaeo-Siberians’ who are closely related to contemporary communities from far-northeastern Siberia (such as the Koryaks), as well as Native Americans; and a Holocene migration of other East Asian-related peoples, who we name ‘Neo-Siberians’, and from whom many contemporary Siberians are descended. Each of these population expansions largely replaced the earlier inhabitants, and ultimately generated the mosaic genetic make-up of contemporary peoples who inhabit a vast area across northern Eurasia and the Americas. Analyses of 34 ancient genomes from northeastern Siberia, dating to between 31,000 and 600 years ago, reveal at least three major migration events in the late Pleistocene population history of the region.

We have previously hypothesized that relatively small and isolated rural communities may experience founder effects, defined as the genetic ramifications of small population sizes at the time of a community's establishment. To explore this, we used an Illumina Infinium Omni2.5Exome-8 chip to collect data from 157 individuals from four Illinois communities, three rural and one urban. Genetic diversity estimates of 999,259 autosomal markers suggested that the reduction in heterozygosity due to shared ancestry was approximately 0, indicating a randomly mating population. An eigenanalysis, which is similar to a principal component analysis but run on a genetic coancestry matrix, conducted in the SNPRelate R package revealed that most of these individuals formed one cluster, with a few putative outliers obscuring population variation. An additional eigenanalysis on the same markers in a combined data set including the 2,504 individuals in the 1000 Genomes database found that most of the 157 Illinois individuals clustered into one group in close proximity to individuals of European descent. A final eigenanalysis of the Illinois individuals with the 503 individuals of European descent (within the 1000 Genomes Project) revealed two clusters of individuals and likely two source populations; one British and one consisting of multiple European subpopulations. We therefore demonstrate the feasibility of examining genetic relatedness across Illinois populations and assessing the number of source populations using publicly available databases. When assessed, population structure information can contribute to the understanding of genetic history in rural populations.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Racial disparities in the US criminal justice system (CJS) have been extensively documented in scholarly work. Critical race scholars have suggested that color-blind racial attitudes inform the set of beliefs that CJS practitioners use in decision making. If this is the case, factors that are related to color-blind racial attitude trends in CJS practitioners must be better understood. We focus on a single CJS practitioner—the police—to assess their color-blind racial beliefs and compare these to the broader US public. Using the Color-Blind Racial Attitudes Scale (CoBRAS), we identified sociodemographic variables associated with high CoBRAS scores in a multiracial lay sample (N = 1401; males and females, mean age = 33.4 years). Police (N = 112) and police recruits (N = 52) CoBRAS scores were compared to CoBRAS scores of lay participants with similar sociodemographics as the police and recruit samples, (respectively, N = 451; N = 291). Police scored significantly higher on the CoBRAS than laypersons even when controlling for sociodemographic variables. Police recruits also have higher CoBRAS scores than laypersons, again controlling for sociodemographic variables. These findings suggest that police work attracts people who endorse color-blind racial beliefs. These findings make understanding the relationship between color-blind racial beliefs and discriminatory behavior of CJS practitioners imperative.

Current genetic and archeological evidence allows for inland, coastal, or multiple pathways to peopling of the Americas., Some recent academic and popular literature implies that the problem of the colonization of the Americas has been largely resolved in favor of one specific model: a Pacific coastal migration, dependent on high marine productivity, from the Bering Strait to South America, thousands of years before Clovis, the earliest widespread cultural manifestation south of the glacial ice. Speculations on maritime adaptations and typological links (stemmed points) across thousands of kilometers have also been advanced. A review of the current genetic, archeological, and paleoecological evidence indicates that ancestral Native American population expansion occurred after 16,000 years ago, consistent with the archeological record, particularly with the earliest securely dated sites after ~15,000 years ago. These data are largely consistent with either an inland (ice-free corridor) or Pacific coastal routes (or both), but neither can be rejected at present. Systematic archeological and paleoecological investigations, informed by geomorphology, are required to test each hypothesis.

Genetic testing is becoming more prevalent in detecting risk and guiding cancer treatment in our increasingly personalized medicine model. However, few studies have examined underserved populations’ perceptions of genetic testing, especially those of rural dwelling populations. We asked residents of three rural communities to complete a self-administered survey gauging their knowledge, attitudes, and perceived barriers for genetic testing. 64.8% of participants of the overall study completed the survey. Most participants were aware of genetic testing for cancer screening (69.0%) and would likely share results with their family (88.5% if it indicated low risk, 85.9% for high risk). Some barriers were noted, including genetic testing not offered in a clinic nearby (46.9%), insurance company knowing the results (54.0%), cost (49.1%), and no accessible genetic counselors with whom to discuss results (45.6%). Our rural participants were generally knowledgeable about genetic testing, but this may not be reflective of all rural populations. Opportunities exist to mitigate use barriers, expand the utilization of telehealth services and regulatory agency-approved assays, and increase knowledge regarding privacy and protections offered by statute, such as the Genetic Information Nondiscrimination Act (US) and General Data Protection Regulation (Europe).

Founder effects in modern populations The genomes of ancient humans can reveal patterns of early human migration (see the Perspective by Achilli et al. ). Iceland has a genetically distinct population, despite relatively recent settlement (∼1100 years ago). Ebenesersdóttir et al. examined the genomes of ancient Icelandic people, dating to near the colonization of Iceland, and compared them with modernday Icelandic populations. The ancient DNA revealed that the founders had Gaelic and Norse origins. Genetic drift since the initial settlement has left modern Icelanders with allele frequencies that are distinctive, although still skewed toward those of their Norse founders. Scheib et al. sequenced ancient genomes from the Channel Islands of California, USA, and Ontario, Canada. The ancient Ontario population was similar to other ancient North Americans, as well as to modern Algonquian-speaking Native Americans. In contrast, the California individuals were more like groups that now live in Mexico and South America. It appears that a genetic split and population isolation likely occurred during the Ice Age, but the peoples remixed at a later date. Science , this issue p. 1028 , p. 1024 ; see also p. 964

Analysis of a mass burial of seven males at CA-ALA-554, a prehistoric site in the Amador Valley, CA, was undertaken to determine if the individuals were "locals" or "non-locals," and how they were genetically related to one another.The study includes osteological, genetic (mtDNA), and stable (C, N, O, S) and radiogenic (Sr) isotope analyses of bone and tooth (first and third molars) samples.Isotopes in first molars, third molars, and bone show they spent the majority of their lives living together. They are not locals to the Amador Valley, but were recently living to the east in the San Joaquin Valley, suggesting intergroup warfare as the cause of death. The men were not maternally related, but represent at least four different matrilines. The men also changed residence as a group between age 16 and adult years.Isotope data suggest intergroup warfare accounts for the mass burial. Genetic data suggest the raiding party included sets of unrelated men, perhaps from different households. Generalizing from this case and others like it, we hypothesize that competition over territory was a major factor behind ancient warfare in Central California. We present a testable model of demographic expansion, wherein villages in high-population-density areas frequently fissioned, with groups of individuals moving to lower-population-density areas to establish new villages. This model is consistent with previous models of linguistic expansion.

Humans first arrived on Madagascar only a few thousand years ago. Subsequent habitat destruction and hunting activities have had significant impacts on the island's biodiversity, including the extinction of megafauna. For example, we know of 17 recently extinct ‘subfossil’ lemur species, all of which were substantially larger (body mass ∼11–160 kg) than any living population of the ∼100 extant lemur species (largest body mass ∼6.8 kg). We used ancient DNA and genomic methods to study subfossil lemur extinction biology and update our understanding of extant lemur conservation risk factors by i) reconstructing a comprehensive phylogeny of extinct and extant lemurs, and ii) testing whether low genetic diversity is associated with body size and extinction risk. We recovered complete or near-complete mitochondrial genomes from five subfossil lemur taxa, and generated sequence data from population samples of two extinct and eight extant lemur species. Phylogenetic comparisons resolved prior taxonomic uncertainties and confirmed that the extinct subfossil species did not comprise a single clade. Genetic diversity estimates for the two sampled extinct species were relatively low, suggesting small historical population sizes. Low genetic diversity and small population sizes are both risk factors that would have rendered giant lemurs especially susceptible to extinction. Surprisingly, among the extant lemurs, we did not observe a relationship between body size and genetic diversity. The decoupling of these variables suggests that risk factors other than body size may have as much or more meaning for establishing future lemur conservation priorities.

As dogs have traveled with humans to every continent, they can potentially serve as an excellent proxy when studying human migration history. Past genetic studies into the origins of Native American dogs have used portions of the hypervariable region (HVR) of mitochondrial DNA (mtDNA) to indicate that prior to European contact the dogs of Native Americans originated in Eurasia. In this study, we summarize past DNA studies of both humans and dogs to discuss their population histories in the Americas. We then sequenced a portion of the mtDNA HVR of 42 pre-Columbian dogs from three sites located in Illinois, coastal British Columbia, and Colorado, and identify four novel dog mtDNA haplotypes. Next, we analyzed a dataset comprised of all available ancient dog sequences from the Americas to infer the pre-Columbian population history of dogs in the Americas. Interestingly, we found low levels of genetic diversity for some populations consistent with the possibility of deliberate breeding practices. Furthermore, we identified multiple putative founding haplotypes in addition to dog haplotypes that closely resemble those of wolves, suggesting admixture with North American wolves or perhaps a second domestication of canids in the Americas. Notably, initial effective population size estimates suggest at least 1000 female dogs likely existed in the Americas at the time of the first known canid burial, and that population size increased gradually over time before stabilizing roughly 1200 years before present.