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- Niemi, Marianna, et al.
(author)
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Temporal Fluctuation in North East Baltic Sea Region Cattle Population Revealed by Mitochondrial and Y-Chromosomal DNA Analyses
- 2015
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In: PLOS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 10:5
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Journal article (peer-reviewed)abstract
- Background Ancient DNA analysis offers a way to detect changes in populations over time. To date, most studies of ancient cattle have focused on their domestication in prehistory, while only a limited number of studies have analysed later periods. Conversely, the genetic structure of modern cattle populations is well known given the undertaking of several molecular and population genetic studies. Results Bones and teeth from ancient cattle populations from the North-East Baltic Sea region dated to the Prehistoric (Late Bronze and Iron Age, 5 samples), Medieval (14), and Post-Medieval (26) periods were investigated by sequencing 667 base pairs (bp) from the mitochondrial DNA (mtDNA) and 155 bp of intron 19 in the Y-chromosomal UTY gene. Comparison of maternal (mtDNA haplotypes) genetic diversity in ancient cattle (45 samples) with modern cattle populations in Europe and Asia (2094 samples) revealed 30 ancient mtDNA haplotypes, 24 of which were shared with modern breeds, while 6 were unique to the ancient samples. Of seven Y-chromosomal sequences determined from ancient samples, six were Y2 and one Y1 haplotype. Combined data including Swedish samples from the same periods (64 samples) was compared with the occurrence of Y-chromosomal haplotypes in modern cattle (1614 samples). Conclusions The diversity of haplogroups was highest in the Prehistoric samples, where many haplotypes were unique. The Medieval and Post-Medieval samples also show a high diversity with new haplotypes. Some of these haplotypes have become frequent in modern breeds in the Nordic Countries and North-Western Russia while other haplotypes have remained in only a few local breeds or seem to have been lost. A temporal shift in Y-chromosomal haplotypes from Y2 to Y1 was detected that corresponds with the appearance of new mtDNA haplotypes in the Medieval and Post-Medieval period. This suggests a replacement of the Prehistoric mtDNA and Y- chromosomal haplotypes by new types of cattle.
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| 2. |
- Palkopoulou, Eleftheria, et al.
(author)
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Holarctic genetic structure and range dynamics in the woolly mammoth
- 2013
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In: Proceedings of the Royal Society of London. Biological Sciences. - : The Royal Society. - 0962-8452 .- 1471-2954. ; 280:1770, s. 20131910-
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Journal article (peer-reviewed)abstract
- Ancient DNA analyses have provided enhanced resolution of population histories in many Pleistocene taxa. However, most studies are spatially restricted, making inference of species-level biogeographic histories difficult. Here, we analyse mitochondrial DNA (mtDNA) variation in the woolly mammoth from across its Holarctic range to reconstruct its history over the last 200 thousand years (kyr). We identify a previously undocumented major mtDNA lineage in Europe, which was replaced by another major mtDNA lineage 32-34 kyr before present (BP). Coalescent simulations provide support for demographic expansions at approximately 121 kyr BP, suggesting that the previous interglacial was an important driver for demography and intraspecific genetic divergence. Furthermore, our results suggest an expansion into Eurasia from America around 66 kyr BP, coinciding with the first exposure of the Bering Land Bridge during the Late Pleistocene. Bayesian inference indicates Late Pleistocene demographic stability until 20-15 kyr BP, when a severe population size decline occurred.
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| 3. |
- Tison, Jean-Luc, 1985-, et al.
(author)
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Signature of post-glacial expansion and genetic structure at the northern range limit of the speckled wood butterfly
- 2014
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In: Biological Journal of the Linnean Society. - : Oxford University Press. - 0024-4066 .- 1095-8312. ; 113:1, s. 136-148
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Journal article (peer-reviewed)abstract
- The post-glacial recolonisation of northern Europe has left distinct signatures in the genomes of many organisms, both due to random demographic processes and divergent natural selection. However, information on differences in genetic variation in conjunction with patterns of local adaptations along latitudinal gradients is often lacking. In this study, we examine genetic diversity and population structure in the speckled wood butterfly Pararge aegeria in northern Europe to investigate the species post-glacial recolonisation history and discuss how this may have affected its life-history evolution. We collected 209 samples and analysed genetic variation in nine microsatellite loci. The results demonstrated a more pronounced population structure in northern Europe compared with populations further south, as well as an overall decrease in genetic diversity with latitude, likely due to founder effects during the recolonisation process. Coalescent simulations coupled with approximate Bayesian computation suggested that central Scandinavia was colonised from the south, rather than from the east. In contrast to further south, populations at the northern range margin are univoltine expressing only one generation per year. This suggests either that univoltinism evolved independently on each side of the Baltic Sea, or that bivoltinism evolved in the south after northern Europe was recolonised.
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