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Simple Summary: Understanding bone diagenesis, or alteration, in juvenile and fetal remains has important implications for forensic science. First, it can suggest information about the deposition of the remains and a possible postmortem interval (PMI). Second, it can assist in evaluating bone integrity and the potential for molecular testing of these remains for forensic purposes. This study investigates how early bone diagenesis is observed in fetal and juvenile mammalian remains as well as differences in degradation based on the deposition of the remains (e.g., blanket wrapping, shallow burial, etc.). We found that there were differences in the extent of bone diagenesis between depositions, with bagged remains exhibiting relatively less degradation over time than the other three depositions, while buried remains exhibited the greatest extent of degradation over time. However, all the remains showed bone diagenesis regardless of time of interment or deposition, with all remains exhibiting alteration as early as three months. This is consistent with adult remains, although the presentation of alteration differs and is likely related to developmental differences between subadult and adult bone. It is well understood that intrinsic factors of bone contribute to bone diagenesis, including bone porosity, crystallinity, and the ratio of organic to mineral components. However, histological analyses have largely been limited to adult bones, although with some exceptions. Considering that many of these properties are different between juvenile and adult bone, the purpose of this study is to investigate if these differences may result in increased degradation observed histologically in fetal and juvenile bone. Thirty-two fetal (n = 16) and juvenile (n = 16) Sus scrofa domesticus femora subject to different depositions over a period of two years were sectioned for histological observation. Degradation was scored using an adapted tunneling index. Results showed degradation related to microbial activity in both fetal and juvenile remains across depositions as early as three months. Buried juvenile remains consistently showed the greatest degradation over time, while the blanket fetal remains showed more minimal degradation. This is likely related to the buried remains' greater contact with surrounding soil and groundwater during deposition. Further, most of the degradation was seen in the subendosteal region, followed by the subperiosteal region, which may suggest the initial microbial attack is from endogenous sources. [ABSTRACT FROM AUTHOR]

Simple Summary: Studies of human fossils, and the DNA extracted from them, reveal a complex history of interbreeding between various human lineages over the last one hundred thousand years. Of particular interest is the nature of the population interactions between the Neandertals of Ice Age Europe and western Asia and the modern humans that eventually replaced them. Here, we used six measurements of the facial skeleton, in samples of Neandertal and early modern human fossils, in an exploratory study aimed at trying to identify geographic regions (from the Near East to western Europe) where interbreeding may have been prevalent enough to have left a signal in the facial morphology of the early modern humans of those regions. Although fossil sample sizes were in some cases very small, the results are consistent with the Near East having played an important role in the introduction of Neandertal genes into the genomes of living humans. Ancient DNA from, Neandertal and modern human fossils, and comparative morphological analyses of them, reveal a complex history of interbreeding between these lineages and the introgression of Neandertal genes into modern human genomes. Despite substantial increases in our knowledge of these events, the timing and geographic location of hybridization events remain unclear. Six measures of facial size and shape, from regional samples of Neandertals and early modern humans, were used in a multivariate exploratory analysis to try to identify regions in which early modern human facial morphology was more similar to that of Neandertals, which might thus represent regions of greater introgression of Neandertal genes. The results of canonical variates analysis and hierarchical cluster analysis suggest important affinities in facial morphology between both Middle and Upper Paleolithic early modern humans of the Near East with Neandertals, highlighting the importance of this region for interbreeding between the two lineages. [ABSTRACT FROM AUTHOR]

Ross and Williams [[4]] argue that there is a benefit to and necessity of embracing studies that employ population structure models to better understand human variation and the historical factors that have influenced it. This Special Issue, "Recent Advances in Forensic Anthropological Methods and Research", with thirteen articles covers a wide range of highly diverse topics within forensic anthropology. The third adult age estimation article by Navega, Costa, and Cunha [[3]] proposes a new method based on a multifactorial macroscopic analysis and deep random neural network models. [Extracted from the article]

Simple Summary: Human remains are often burned in an effort to conceal the identity of the victim and/or obscure traumatic injuries related to the death event. Thermal exposure can produce artifacts resembling trauma and disguise preexisting trauma. However, there is a paucity of experimental studies with varied results addressing the differentiation of thermally induced artifacts from traumatic signatures. To address this gap in the literature, we conducted a small-scale study using domestic pigs as correlates to test the impact of thermal alteration on blunt force trauma to the cranium. Two tools (e.g., hammer and crowbar) were utilized to manually inflict injuries on the human analogs before controlled burning in an outdoor environment. The results of this experiment demonstrated that the most diagnostic variable to differentiate thermally induced alternations from blunt force fractures was fracture pattern. In forensic scenarios involving homicide, human remains are often exposed to fire as a means of disposal and/or obscuring identity. Burning human remains can result in the concealment of traumatic injury, the creation of artifacts resembling injury, or the destruction of preexisting trauma. Since fire exposure can greatly influence trauma preservation, methods to differentiate trauma signatures from burning artifacts are necessary to conduct forensic analyses. Specifically, in the field of forensic anthropology, criteria to distinguish trauma from fire signatures on bone is inconsistent and sparse. This study aims to supplement current forensic anthropological literature by identifying criteria found to be the most diagnostic of fire damage or blunt force trauma. Using the skulls of 11 adult pigs (Sus scrofa), blunt force trauma was manually produced using a crowbar and flat-faced hammer. Three specimens received no impacts and were utilized as controls. All skulls were relocated to an outdoor, open-air fire where they were burned until a calcined state was achieved across all samples. Results from this experiment found that blunt force trauma signatures remained after burning and were identifiable in all samples where reassociation of fragments was possible. This study concludes that distinct patterns attributed to thermal fractures and blunt force fractures are identifiable, allowing for diagnostic criteria to be narrowed down for future analyses. [ABSTRACT FROM AUTHOR]

Simple Summary: Within the practice of forensic anthropology ancestry is oftentimes used as a proxy for social race. This concept and its implications were explored via a content analysis (2009–2019) of the Journal of Forensic Sciences. Our findings revealed antiquated views of race based on the trifecta of continental populations (Asia, Europe, and Africa) continue to be pervasive in the field despite scientific invalidation of the concept of race decades earlier. Moreover, our employment of modern geometric morphometric and spatial analysis methods on craniofacial coordinate anatomical landmarks from several Latin American samples produced results in which the groups were not patterned by ancestry trifecta. Based on our findings we propose replacing the assumption of continental ancestry with a population structure approach that combines microevolutionary and cultural factors with historical events in the examination of population affinity. One of the parameters forensic anthropologists have traditionally estimated is ancestry, which is used in the United States as a proxy for social race. Its use is controversial because the biological race concept was debunked by scientists decades ago. However, many forensic anthropologists contend, in part, that because social race categories used by law enforcement can be predicted by cranial variation, ancestry remains a necessary parameter for estimation. Here, we use content analysis of the Journal of Forensic Sciences for the period 2009–2019 to demonstrate the use of various nomenclature and resultant confusion in ancestry estimation studies, and as a mechanism to discuss how forensic anthropologists have eschewed a human variation approach to studying human morphological differences in favor of a simplistic and debunked typological one. Further, we employ modern geometric morphometric and spatial analysis methods on craniofacial coordinate anatomical landmarks from several Latin American samples to test the validity of applying the antiquated tri-continental approach to ancestry (i.e., African, Asian, European). Our results indicate groups are not patterned by the ancestry trifecta. These findings illustrate the benefit and necessity of embracing studies that employ population structure models to better understand human variation and the historical factors that have influenced it. [ABSTRACT FROM AUTHOR]