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Sawafuji, R.

Publications and source records attributed to Sawafuji, R..

5 recordsLinked to original sources

Denisovan leg bones from Taiwan reveal large body size

Denisovans are an extinct archaic Homo group whose lineage diverged from the Neanderthal lineage approximately 550,000 years ago and were widely distributed across eastern Asia until [~]45,000 years ago1-7. Their morphological features are known directly from the existing cranio- dental and phalangeal remains1,2,8-12. However, the body size and postcranial morphology of the Denisovans remain largely unknown. We here report that hominin femoral and tibial fossils recovered from the Penghu Channel, Taiwan, are Denisovans in their proteomic profiles. Morphologically, these specimens are among the largest leg bones known in Pleistocene Homo. They exhibit generally archaic features, but also show some modern human-like morphology, including a strong femoral pilaster. Our findings demonstrate that the Denisovan population at the northern circle had larger body size than earlier Homo erectus as well as Late Pleistocene Homo sapiens in eastern Asia. This challenges the generally held expectation that Pleistocene Homo followed Bergmanns rule that anticipates latitudinal decline of body size, and suggests that the large Denisovan brain resulted from their large body size at least partly. The strong pilaster developed in the Penghu femur suggests some behavioral similarities between the Denisovans and the Upper Palaeolithic modern humans and/or gene flow from the latter to the former.

paleontology↗

From bones to sediments: ancient human DNA from open-air archaeological sites

Ancient human bones degrade and sometimes disappear, especially in regions with acidic soils, making it difficult to obtain genetic information from past populations. To explore alternative sources, we analyzed ancient DNA from sediment samples collected from a burial site and a settlement site in Japan, both dating to around 1000 years ago. We found that ancient human mitochondrial DNA was obtained from sediments surrounding bones, particularly close to rib bones, while human DNA was rarely detected in the settlement site sediments. Furthermore, the mitochondrial haplogroups identified in the sediments were identical to those from human bones, confirming the reliability of this approach. Our findings suggest that genetic information about past human populations can be directly obtained from archaeological sediments in open-air sites. This method also provides a non-destructive alternative to bones and teeth, expanding possibilities for ancient DNA research in regions where skeletal remains are poorly preserved.

molecular biology↗

Early Pastoralism in Central European Forests: Insights from Ancient Environmental Genomics

Central European forests have been shaped by complex human interactions throughout the Holocene, with significant changes following the introduction of domesticated animals in the Neolithic ([~]7.5 - 6.0 kyr BP). However, understanding early pastoral practices and their impact on forests is limited by methods for detecting animal movement across past landscapes. Here we examine ancient sedimentary DNA (sedaDNA) preserved at the Velky Mamu[t]ak rock shelter, in northern Bohemia (Czech Republic), which has been a forested enclave since the early Holocene. We find that domesticated animals, their associated microbiomes, and plants potentially gathered for fodder, have clear representation by the Late Neolithic, around 6.0 kyr BP, and persist throughout the Bronze Age into recent times. We identify a change in dominant grazing species from sheep to pigs in the Bronze Age ([~]4.1 - 3.0 kyr BP) and interpret the impact this had in the mid-Holocene retrogressions that still define the structure of Central European forests today. This study highlights the ability of ancient metagenomics to bridge archaeological and paleoecological methods and provide an enhanced perspective on the roots of the Anthropocene.

genomics↗

Palaeoproteomic investigation of an ancient human skeleton with abnormal deposition of dental calculus

Detailed investigation of extremely severe pathological conditions in ancient human skeletons is important as it could shed light on the breadth of potential interactions between humans and disease etiologies in the past. Here, we applied palaeoproteomics to investigate an ancient human skeletal individual with severe oral pathology, focusing our research on bacterial pathogenic factors and host defense response. This female skeleton, from the Okhotsk period (i.e., 5th-13th century) of Northern Japan, poses relevant amounts of abnormal dental calculus deposition and exhibits oral dysfunction due to severe periodontal disease. A shotgun mass-spectrometry analysis identified 81 human proteins and 15 bacterial proteins from the calculus of the subject. We identified two pathogenic or bioinvasive proteins originating from two of the three "red complex" bacteria, the core species associated with severe periodontal disease in modern humans, as well as two additional bioinvasive proteins of periodontal-associated bacteria. Moreover, we discovered defense response system-associated human proteins, although their proportion was mostly similar to those reported in ancient and modern human individuals with lower calculus deposition. These results suggest that the bacterial etiology was similar and the host defense response was not necessarily more intense in ancient individuals with significant amounts of abnormal dental calculus deposition.

evolutionary biology↗

Ancient DNA analysis of food remains in human dental calculus from the Edo period, Japan

Objectives: Although there are many methods for reconstructing diets of the past, detailed taxon identification is still challenging, and most plants hardly remain at a site. In this study, we applied DNA metabarcoding to dental calculus of Edo people for the taxonomic identification of food species.\n\nMaterials and Methods: DNA was extracted from 13 human dental calculi from the Unko-in site (18th-19th century) of the Edo period, Japan. Polymerase chain reaction (PCR) and sequencing were performed using a primer set specific to the genus Oryza, because rice (Oryza sativa) was a staple food and this was the only member of this genus present in Japan at that time. DNA metabarcoding targeting plants, animals (meat and fish), and fungi was also carried out to investigate dietary diversity.\n\nResults: We detected amplified products of the genus Oryza from more than half of the samples using PCR and Sanger sequencing. DNA metabarcoding enabled us to identify taxa of plants and fungi, although taxa of animals were not detected, except human.\n\nDiscussion: Most of the plant taxonomic groups are present in Japan and include species consumed as food at that time, as confirmed by historical literature. The other groups featured in the lifestyle of Edo people, such as for medicinal purposes and tobacco. The results indicate that plant DNA analysis from calculus provides information about food diversity and lifestyle habits from the past and can complement other analytical methods such as starch analysis and stable isotope analysis.

molecular biology↗