| 1. |
- Ameen, Carly, et al.
(författare)
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Specialized sledge dogs accompanied Inuit dispersal across the North American Arctic
- 2019
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Ingår i: Proceedings of the Royal Society of London. Biological Sciences. - : The Royal Society. - 0962-8452 .- 1471-2954. ; 286:1916
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Tidskriftsartikel (refereegranskat)abstract
- Domestic dogs have been central to life in the North American Arctic for millennia. The ancestors of the Inuit were the first to introduce the widespread usage of dog sledge transportation technology to the Americas, but whether the Inuit adopted local Palaeo-Inuit dogs or introduced a new dog population to the region remains unknown. To test these hypotheses, we generated mitochondrial DNA and geometric morphometric data of skull and dental elements from a total of 922 North American Arctic dogs and wolves spanning over 4500 years. Our analyses revealed that dogs from Inuit sites dating from 2000 BP possess morphological and genetic signatures that distinguish them from earlier Palaeo-Inuit dogs, and identified a novel mitochondrial clade in eastern Siberia and Alaska. The genetic legacy of these Inuit dogs survives today in modern Arctic sledge dogs despite phenotypic differences between archaeological and modern Arctic dogs. Together, our data reveal that Inuit dogs derive from a secondary pre-contact migration of dogs distinct from Palaeo-Inuit dogs, and probably aided the Inuit expansion across the North American Arctic beginning around 1000 BP.
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| 2. |
- Frantz, Laurent A. F., et al.
(författare)
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Genomic and archaeological evidence suggests a dual origin of domestic dogs
- 2016
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Ingår i: Science. - : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 352:6290, s. 1228-1231
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Tidskriftsartikel (refereegranskat)abstract
- The geographic and temporal origins of dogs remain controversial. We generated genetic sequences from 59 ancient dogs and a complete (28x) genome of a late Neolithic dog (dated to similar to 4800 calendar years before the present) from Ireland. Our analyses revealed a deep split separating modern East Asian and Western Eurasian dogs. Surprisingly, the date of this divergence (similar to 14,000 to 6400 years ago) occurs commensurate with, or several millennia after, the first appearance of dogs in Europe and East Asia. Additional analyses of ancient and modern mitochondrial DNA revealed a sharp discontinuity in haplotype frequencies in Europe. Combined, these results suggest that dogs may have been domesticated independently in Eastern and Western Eurasia from distinct wolf populations. East Eurasian dogs were then possibly transported to Europe with people, where they partially replaced European Paleolithic dogs.
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| 3. |
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| 4. |
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| 5. |
- Ollivier, Morgane, et al.
(författare)
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Amy2B copy number variation reveals starch diet adaptations in ancient European dogs
- 2016
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Ingår i: Royal Society Open Science. - : The Royal Society. - 2054-5703. ; 3:11
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Tidskriftsartikel (refereegranskat)abstract
- Extant dog and wolf DNA indicates that dog domestication was accompanied by the selection of a series of duplications on the Amy2B gene coding for pancreatic amylase. In this study, we used a palaeogenetic approach to investigate the timing and expansion of the Amy2B gene in the ancient dog populations of Western and Eastern Europe and Southwest Asia. Quantitative polymerase chain reaction was used to estimate the copy numbers of this gene for 13 ancient dog samples, dated to between 15 000 and 4000 years before present (cal. BP). This evidenced an increase of Amy2B copies in ancient dogs from as early as the 7th millennium cal. BP in Southeastern Europe. We found that the gene expansion was not fixed across all dogs within this early farming context, with ancient dogs bearing between 2 and 20 diploid copies of the gene. The results also suggested that selection for the increased Amy2B copy number started 7000 years cal. BP, at the latest. This expansion reflects a local adaptation that allowed dogs to thrive on a starch rich diet, especially within early farming societies, and suggests a biocultural coevolution of dog genes and human culture.
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| 6. |
- Ollivier, Morgane, et al.
(författare)
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Dogs accompanied humans during the Neolithic expansion into Europe
- 2018
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Ingår i: Biology Letters. - : The Royal Society. - 1744-9561 .- 1744-957X. ; 14:10
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Tidskriftsartikel (refereegranskat)abstract
- Near Eastern Neolithic farmers introduced several species of domestic plants and animals as they dispersed into Europe. Dogs were the only domestic species present in both Europe and the Near East prior to the Neolithic. Here, we assessed whether early Near Eastern dogs possessed a unique mitochondrial lineage that differentiated them from Mesolithic European populations. We then analysed mitochondrial DNA sequences from 99 ancient European and Near Eastern dogs spanning the Upper Palaeolithic to the Bronze Age to assess if incoming farmers brought Near Eastern dogs with them, or instead primarily adopted indigenous European dogs after they arrived. Our results show that European pre-Neolithic dogs all possessed the mitochondrial haplogroup C, and that the Neolithic and Post-Neolithic dogs associated with farmers from Southeastern Europe mainly possessed haplogroup D. Thus, the appearance of haplogroup D most probably resulted from the dissemination of dogs from the Near East into Europe. In Western and Northern Europe, the turnover is incomplete and haplogroup C persists well into the Chalcolithic at least. These results suggest that dogs were an integral component of the Neolithic farming package and a mitochondrial lineage associated with the Near East was introduced into Europe alongside pigs, cows, sheep and goats. It got diluted into the native dog population when reaching the Western and Northern margins of Europe.
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| 7. |
- Palkopoulou, Eleftheria, et al.
(författare)
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Synchronous genetic turnovers across Western Eurasia in Late Pleistocene collared lemmings
- 2016
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Ingår i: Global Change Biology. - : Wiley. - 1354-1013 .- 1365-2486. ; 22:5, s. 1710-1721
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Tidskriftsartikel (refereegranskat)abstract
- Recent palaeogenetic studies indicate a highly dynamic history in collared lemmings (Dicrostonyx spp.), with several demographical changes linked to climatic fluctuations that took place during the last glaciation. At the western range margin of D.torquatus, these changes were characterized by a series of local extinctions and recolonizations. However, it is unclear whether this pattern represents a local phenomenon, possibly driven by ecological edge effects, or a global phenomenon that took place across large geographical scales. To address this, we explored the palaeogenetic history of the collared lemming using a next-generation sequencing approach for pooled mitochondrial DNA amplicons. Sequences were obtained from over 300 fossil remains sampled across Eurasia and two sites in North America. We identified five mitochondrial lineages of D.torquatus that succeeded each other through time across Europe and western Russia, indicating a history of repeated population extinctions and recolonizations, most likely from eastern Russia, during the last 50000years. The observation of repeated extinctions across such a vast geographical range indicates large-scale changes in the steppe-tundra environment in western Eurasia during the last glaciation. AllHolocene samples, from across the species' entire range, belonged to only one of the five mitochondrial lineages. Thus, extant D.torquatus populations only harbour a small fraction of the total genetic diversity that existed across different stages of the Late Pleistocene. In North American samples, haplotypes belonging to both D.groenlandicus and D.richardsoni were recovered from a Late Pleistocene site in south-western Canada. This suggests that D.groenlandicus had a more southern and D.richardsoni a more northern glacial distribution than previously thought. This study provides significant insights into the population dynamics of a small mammal at a large geographical scale and reveals a rather complex demographical history, which could have had bottom-up effects in the Late Pleistocene steppe-tundra ecosystem.
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| 9. |
- Smith, Steve, et al.
(författare)
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Nonreceding hare lines : genetic continuity since the Late Pleistocene in European mountain hares (Lepus timidus)
- 2017
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Ingår i: Biological Journal of the Linnean Society. - : Oxford University Press (OUP). - 0024-4066 .- 1095-8312. ; 120:4, s. 891-908
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Tidskriftsartikel (refereegranskat)abstract
- Throughout time, climate changes have caused substantial rearrangements of habitats which have alternately promoted and disfavoured different types of taxa. At first glance, the mountain hare (Lepus timidus) shows the typical hallmarks of a cold-adapted species that has retreated to refugia since the onset of the current Holocene interglacial. In contrary to expectations, however, the species has a high contemporary genetic diversity with no clear differentiation between geographically isolated populations. In order to clarify the phylogeographic history of European mountain hares, we here analysed ancient DNA from the glacial populations that inhabited the previous midlatitude European tundra region. Our results reveal that the Ice Age hares had similar levels of genetic variation and lack of geographic structure as observed today, and the ancient samples were intermingled with modern individuals throughout the reconstructed evolutionary tree. This suggests a temporal genetic continuity in Europe, where the mountain hares were able to keep pace with the rapid changes at the last glacial/ interglacial transition and successfully track their shifting habitat to northern and alpine regions. Further, the temporal demographic analyses showed that the species' population size in Europe appears to have been tightly linked with palaeoclimatic fluctuations, with increases and declines occurring during periods of global cooling and warming, respectively. Taken together, our results suggest that neither habitat shifts nor demographic fluctuations have had any substantial impact on the genetic diversity of European mountain hares. This remarkable resilience, which contrasts to a majority of previously investigated cold-adapted species, is likely due to its generalist nature that makes it less vulnerable to environmental changes.
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