| 1. |
- Frantz, Laurent A. F., et al.
(författare)
-
Ancient pigs reveal a near-complete genomic turnover following their introduction to Europe
- 2019
-
Ingår i: Proceedings of the National Academy of Sciences of the United States of America. - : Proceedings of the National Academy of Sciences. - 0027-8424 .- 1091-6490. ; 116:35, s. 17231-17238
-
Tidskriftsartikel (refereegranskat)abstract
- Archaeological evidence indicates that pig domestication had begun by similar to 10,500 y before the present ( BP) in the Near East, and mitochondrial DNA ( mtDNA) suggests that pigs arrived in Europe alongside farmers similar to 8,500 y BP. A few thousand years after the introduction of Near Eastern pigs into Europe, however, their characteristic mtDNA signature disappeared and was replaced by haplotypes associated with European wild boars. This turnover could be accounted for by substantial gene flow from local European wild boars, although it is also possible that European wild boars were domesticated independently without any genetic contribution from the Near East. To test these hypotheses, we obtained mtDNA sequences from 2,099 modern and ancient pig samples and 63 nuclear ancient genomes from Near Eastern and European pigs. Our analyses revealed that European domestic pigs dating from 7,100 to 6,000 y BP possessed both Near Eastern and European nuclear ancestry, while later pigs possessed no more than 4% Near Eastern ancestry, indicating that gene flow from European wild boars resulted in a near-complete disappearance of Near East ancestry. In addition, we demonstrate that a variant at a locus encoding black coat color likely originated in the Near East and persisted in European pigs. Altogether, our results indicate that while pigs were not independently domesticated in Europe, the vast majority of human-mediated selection over the past 5,000 y focused on the genomic fraction derived from the European wild boars, and not on the fraction that was selected by early Neolithic farmers over the first 2,500 y of the domestication process.
|
|
| 2. |
- Gron, Kurt J., et al.
(författare)
-
Archaeological cereals as an isotope record of long-term soil health and anthropogenic amendment in southern Scandinavia
- 2021
-
Ingår i: Quaternary Science Reviews. - : Elsevier BV. - 0277-3791. ; 253
-
Tidskriftsartikel (refereegranskat)abstract
- Maintaining soil health is integral to agricultural production, and the archaeological record contains multiple lines of palaeoclimatic and palaeoenvironmental proxy evidence that can contribute to the understanding and analysis of long-term trajectories of change that are key for contextualizing 21st century global environmental challenges. Soil is a capital resource and its nutrient balance is modified by agricultural activities, making it necessary to ensure soil productivity is maintained and managed through human choices and actions. Since prehistory this has always been the case; soil is a non-renewable resource within a human lifetime. Here, we present and interpret carbon and nitrogen isotope analysis of charred cereals from southern Scandinavia. Anthropogenic effects on soils are evident from the initiation of farming 6000 years ago, as is amendment to counteract its effects. The earliest cereals were planted on pristine soils, and by the late Neolithic, agriculture extensified. By the Iron Age it was necessary to significantly amend depleted soils to maintain crop yields. We propose that these data provide a record of soil water retention, net precipitation and amendment. From the start of the Neolithic there is a concurrent decrease in both Δ13C and δ15N, mitigated only by the replacement of soil organic content in the form of manure in the Iron Age. The cereal isotopes provide a record of trajectories of agricultural sustainability and anthropogenic adaptation for nearly the entire history of farming in the region.
|
|
| 3. |
- Gron, Kurt J., et al.
(författare)
-
Nitrogen isotope evidence for manuring of early Neolithic Funnel Beaker Culture cereals from Stensborg, Sweden
- 2017
-
Ingår i: Journal of Archaeological Science: Reports. - : Elsevier BV. - 2352-409X. ; 14, s. 575-579
-
Tidskriftsartikel (refereegranskat)abstract
- Little is known about arable agriculture in the Early Neolithic (4000–3300 cal BC, Funnel Beaker Culture) of Southern Scandinavia. Archaeobotanical material is rare and few archaeological sites have yielded more than a small number of charred cereal grains. In this short communication, we present single-entity carbon and nitrogen isotope analyses of charred cereals from Stensborg, an early Funnel Beaker Culture site near Stockholm, Sweden. This cereal assemblage is important as it is large, well-preserved and consists of multiple crop species. Our isotopic results indicate that many of the Stensborg cereal crops had been manured and that there is intra- and inter-species variation in manuring. We interpret these data as evidence of an integrated regime of stock-keeping and small-scale agriculture in the early Funnel Beaker Culture near its northernmost limit.
|
|
| 4. |
- Mellows, Andrew, et al.
(författare)
-
The impact of past climate change on genetic variation and population connectivity in the Icelandic arctic fox
- 2012
-
Ingår i: Proceedings of the Royal Society of London. Biological Sciences. - : The Royal Society. - 0962-8452 .- 1471-2954. ; 279:1747, s. 4568-4573
-
Tidskriftsartikel (refereegranskat)abstract
- Previous studies have suggested that the presence of sea ice is an important factor in facilitating migration and determining the degree of genetic isolation among contemporary arctic fox populations. Because the extent of sea ice is dependent upon global temperatures, periods of significant cooling would have had a major impact on fox population connectivity and genetic variation. We tested this hypothesis by extracting and sequencing mitochondrial control region sequences from 17 arctic foxes excavated from two late-ninth-century to twelfth-century AD archaeological sites in northeast Iceland, both of which predate the Little Ice Age (approx. sixteenth to nineteenth century). Despite the fact that five haplotypes have been observed in modern Icelandic foxes, a single haplotype was shared among all of the ancient individuals. Results from simulations within an approximate Bayesian computation framework suggest that the rapid increase in Icelandic arctic fox haplotype diversity can only be explained by sea-ice-mediated fox immigration facilitated by the Little Ice Age.
|
|
