| 1. |
- Rasmussen, Simon, et al.
(författare)
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Early Divergent Strains of Yersinia pestis in Eurasia 5,000 Years Ago
- 2015
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Ingår i: Cell. - : Elsevier. - 0092-8674. ; 163:3, s. 571-582
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Tidskriftsartikel (refereegranskat)abstract
- The bacteria Yersinia pestis is the etiological agent of plague and has caused human pandemics with millions of deaths in historic times. How and when it originated remains contentious. Here, we report the oldest direct evidence of Yersinia pestis identified by ancient DNA in human teeth from Asia and Europe dating from 2,800 to 5,000 years ago. By sequencing the genomes, we find that these ancient plague strains are basal to all known Yersinia pestis. We find the origins of the Yersinia pestis lineage to be at least two times older than previous estimates. We also identify a temporal sequence ofgenetic changes that lead to increased virulenceand the emergence of the bubonic plague. Our results show that plague infection was endemic in the human populations of Eurasia at least 3,000 years before any historical recordings of pandemics.
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| 2. |
- Saag, Lehti, et al.
(författare)
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The Arrival of Siberian Ancestry Connecting the Eastern Baltic to Uralic Speakers further East
- 2019
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Ingår i: Current Biology. - : Elsevier BV. - 0960-9822 .- 1879-0445. ; 29:10, s. 1701-
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Tidskriftsartikel (refereegranskat)abstract
- In this study, we compare the genetic ancestry of individuals from two as yet genetically unstudied cultural traditions in Estonia in the context of available modern and ancient datasets: 15 from the Late Bronze Age stone-cist graves (1200-400 BC) (EstBA) and 6 from the Pre-Roman Iron Age tarand cemeteries (800/500 BC-50 AD) (EstIA). We also included 5 Pre-Roman to Roman Iron Age Ingrian (500 BC450 AD) (IngIA) and 7 Middle Age Estonian (1200-1600 AD) (EstMA) individuals to build a dataset for studying the demographic history of the northern parts of the Eastern Baltic from the earliest layer of Mesolithic to modern times. Our findings are consistent with EstBA receiving gene flow from regions with strong Western hunter-gatherer (WHG) affinities and EstIA from populations related to modern Siberians. The latter inference is in accordance with Y chromosome (chrY) distributions in present day populations of the Eastern Baltic, as well as patterns of autosomal variation in the majority of the westernmost Uralic speakers [1-5]. This ancestry reached the coasts of the Baltic Sea no later than the mid-first millennium BC; i.e., in the same time window as the diversification of west Uralic (Finnic) languages [6]. Furthermore, phenotypic traits often associated with modern Northern Europeans, like light eyes, hair, and skin, as well as lactose tolerance, can be traced back to the Bronze Age in the Eastern Baltic.
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| 3. |
- Wärmländer, Sebastian K. T. S., et al.
(författare)
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Estimating the Temperature of Heat-exposed Bone via Machine Learning Analysis of SCI Color Values : A Pilot Study
- 2019
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Ingår i: Journal of Forensic Sciences. - : Wiley. - 0022-1198 .- 1556-4029. ; 64:1, s. 190-195
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Tidskriftsartikel (refereegranskat)abstract
- Determining maximum heating temperatures of burnt bones is a long-standing problem in forensic science and archaeology. In this pilot study, controlled experiments were used to heat 14 fleshed and defleshed pig vertebrae (wet bones) and archaeological human vertebrae (dry bones) to temperatures of 400, 600, 800, and 1000 degrees C. Specular component included (SCI) color values were recorded from the bone surfaces with a Konica-Minolta cm-2600d spectrophotometer. These color values were regressed onto heating temperature, using both a traditional linear model and the k-nearest neighbor (k-NN) machine-learning algorithm. Mean absolute errors (MAE) were computed for 1000 rounds of temperature prediction. With the k-NN approach, the median MAE prediction errors were 41.6 degrees C for the entire sample, and 20.9 degrees C for the subsample of wet bones. These results indicate that spectrophotometric color measurements combined with machine learning methods can be a viable tool for estimating bone heating temperature.
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