The Indo-European languages are among the most widely spoken in the world, yet their early diversification remains contentious. It is widely accepted that the spread of this language family across Europe from the 5th millennium BP correlates with the expansion and diversification of steppe-related genetic ancestry from the onset of the Bronze Age. However, multiple steppe-derived populations co-existed in Europe during this period, and it remains unclear how these populations diverged and which provided the demographic channels for the ancestral forms of the Italic, Celtic, Greek, and Armenian languages.
View Article and Find Full Text PDFOver the last forty years an indeterminate number of persons, ranging from thousands to tens of thousands, have died along the US-Mexico border during migration, fleeing poverty, armed conflict, situations of violence, and disasters. An accurate accounting of migrant deaths along the southern US border is the first step toward an understanding of the extent and the contributing factors of these deaths. In this article, we describe a key aspect of our collaborative work aimed at developing a more representative account of migrant mortality along the southwestern US border: the determination of criteria for inclusion of specific forensic cases as "migrant.
View Article and Find Full Text PDFObjectives: The study of growth in the past is a critical component of bioarcheological analyses. However, our understanding of growth in the past is subject to a number of methodological challenges. This study aims to model the skeletal growth of past populations by considering the challenges associated with the data collection process and the challenges associated with the age estimation procedures.
View Article and Find Full Text PDFA variety of mechanisms including transcriptional silencing, gene copy loss, and increased susceptibility to cellular stress have been associated with a sudden or gradual loss of monoclonal antibody (mAb) production in Chinese hamster ovary (CHO) cell lines. In this study, we utilized single-cell RNA-seq (scRNA-seq) to study a clonally derived CHO cell line that underwent production instability leading to a dramatic reduction of the levels of mAb produced. From the scRNA-seq data, we identified subclusters associated with variations in the mAb transgenes and observed that heavy chain gene expression was significantly lower than that of the light chain across the population.
View Article and Find Full Text PDFEcological release, originally conceived as niche expansion following a reduction in interspecific competition, may prompt invasion success, morphological evolution, speciation, and other ecological and evolutionary outcomes. However, the concept has not been recently reviewed. Here, we trace the study of 'ecological release' from its inception through the present day and find that current definitions are broad and highly varied.
View Article and Find Full Text PDFNegative interactions between species can generate divergent selection that causes character displacement. However, other processes cause similar divergence. We use spatial and temporal replication across island populations of Anolis lizards to assess the importance of negative interactions in driving trait shifts.
View Article and Find Full Text PDFSpecies can compete both directly via aggressive encounters (interference) and indirectly through their shared use of a limited resource (exploitation). Depending on the circumstances interference, exploitation, and their interplay can either lead to competitive exclusion or drive niche partitioning to maintain species coexistence. Thus, understanding species coexistence in nature requires accurately identifying the mechanisms that contribute to competition among the species in question.
View Article and Find Full Text PDFIn 2012, Texas surpassed Arizona in migrant deaths. The majority of deaths occurred in the Rio Grande Valley, specifically in Brooks County, Texas. Brooks County is one of the poorest in the state and was overwhelmed with deaths, without appropriate resources to follow the state laws pertaining to the investigation of unidentified human remains.
View Article and Find Full Text PDFObjectives: The current study seeks to determine if a sample of foragers, farmers, and pastoralists are distinguishable based on their dental microwear texture signatures.
Materials And Methods: The study included a sample of 719 individuals from 51 archeological sites (450 farmers, 192 foragers, 77 pastoralists). All were over age 12 and sexes were pooled.
Dental development is one of the most widely utilized and accurate methods available for estimating age in subadult skeletal remains. The timing of tooth growth and development is regulated by genetics and less affected by external factors, allowing reliable estimates of chronological age. Traditional methodology focuses on comparing tooth developmental scores to corresponding age charts.
View Article and Find Full Text PDFIsoscape refinement is an essential component for accurately predicting region-of-origin in forensic investigations involving isotope analysis of unidentified human remains. Stable oxygen (δ O) and hydrogen (δ H) isotopes were measured from 57 tap water samples collected across Mississippi to model refined isoscapes for the state. A tap water conversion equation, δ O =1.
View Article and Find Full Text PDFThis research presents a new software, "Fragmento", for accurate analyses of fragmentary human skeletal remains and facilitation of three-dimensional (3D) fragmentary matching and full bone reconstruction. The framework utilizes the power of statistical bone atlases to create 3D templates for bone matching and to interpolate missing anatomy for full bone reconstruction. Developed tool has enhanced features allowing the user to visualize, review and scale all scanned skeletal remains within a 3D statistical template, merging accepted registered elements to provide a fully reconstructed bone.
View Article and Find Full Text PDFUnderstanding ecosystem resilience to human impacts is critical for conservation and restoration. The large-scale die-off of New England salt marshes was triggered by overfishing and resulted from decades of runaway crab grazing. In 2009, however, cordgrass began to recover, decreasing die-off -40% by 2010.
View Article and Find Full Text PDFOverexploitation of predators has been linked to the collapse of a growing number of shallow-water marine ecosystems. However, salt-marsh ecosystems are often viewed and managed as systems controlled by physical processes, despite recent evidence for herbivore-driven die-off of marsh vegetation. Here we use field observations, experiments, and historical records at 14 sites to examine whether the recently reported die-off of northwestern Atlantic salt marshes is associated with the cascading effects of predator dynamics and intensive recreational fishing activity.
View Article and Find Full Text PDFTrotter and Gleser's (1-3) stature equations, conventionally used to estimate stature, are not appropriate to use in the modern forensic context. In this study, stature is assessed with a modern (birth years after 1944) American sample (N = 242) derived from the National Institute of Justice Database for Forensic Anthropology in the United States and the Forensic Anthropology Databank. New stature formulae have been calculated using forensic stature (FSTAT) and a combined dataset of forensic, cadaver, and measured statures referred to as Any Stature (ASTAT).
View Article and Find Full Text PDFEstimation of living stature has obvious utility in the identification process. Typically, anthropologists estimate stature from the measurement of long bone length. This type of analysis is traditionally conducted on skeletonized or badly decomposed remains, so collection of the necessary bone measurements is relatively simple.
View Article and Find Full Text PDFA great deal has previously been written about the use of skeletal morphological changes in estimating ages-at-death. This article looks in particular at the pubic symphysis, as it was historically one of the first regions to be described in the literature on age estimation. Despite the lengthy history, the value of the pubic symphysis in estimating ages and in providing evidence for putative identifications remains unclear.
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