Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Genetic structure in the North- population connectivity and social organization in the Arctic fox
Stockholm University, Faculty of Science, Department of Zoology.ORCID iD: 0000-0002-9707-5206
2010 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

Genetic variation is distributed on different spatial and temporal scales, reflecting the ecological and geographical complexity in the habitat. In this thesis, the primary objective was to obtain a comprehensive understanding of the genetic structuring in the Arctic fox (Vulpes lagopus) and to identify the underlying factors forming these structures. Using microsatellites, presence of sea ice was identified as the main factor determining the large-scale genetic structure in the Arctic fox. Genetic distinctiveness was demonstrated for populations surrounded by year-round open water (i.e. Iceland and Scandinavia) and among areas connected by sea ice, genetic differentiation was mainly determined by the geographic distance (PAPER I). Movement across the sea ice was influenced by fluctuations in resource abundance caused by the lemming cycle. As a consequence of low lemming abundance, long-distance movement from inland habitats into coastal habitats influenced the genetic structure on a temporal scale (PAPER II). Although the global connectivity was determined by few underlying factors, local population structures were influenced by population-specific historical, demographic and ecological factors (PAPER II, III, IV). Geographical barriers determined genetic structure within the isolated population on Iceland (PAPER III), whereas immigration influenced the local genetic structure in both Svalbard (PAPER II) and Scandinavia (PAPER IV). When population size is low, few immigration events cause rapid changes in genetic composition (PAPER IV), while immigration had a less pronounced effect in larger populations (PAPER II). On the social scale, high flexibility regarding the composition of social groups was recorded as a likely response to local habitat conditions (PAPER V). Complex social groups were more common in habitats with high resource availability and presence of predators than in habitats without predation. This thesis illustrates the importance of ecology and demography forming genetic structure at different scales, and highlights the Arctic fox vulnerability to the ongoing climate change.

Place, publisher, year, edition, pages
Stockholm: Department of Zoology, Stockholm University , 2010. , 19 p.
National Category
Biological Sciences
Research subject
Animal Ecology
Identifiers
URN: urn:nbn:se:su:diva-43529ISBN: 978-91-7447-155-7 (print)OAI: oai:DiVA.org:su-43529DiVA: diva2:357599
Public defence
2010-11-26, Magnélisalen, Kemiska övningslaboratoriet, Svante Arrhenius väg 16 B, Stockholm, 10:00 (English)
Opponent
Supervisors
Note
At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 1: In press. Paper 2: Manuscript. Paper 5: Manuscript. Available from: 2010-11-03 Created: 2010-10-19 Last updated: 2014-10-13Bibliographically approved
List of papers
1. Arctic fox Vulpes lagopus population structure: circumpolar patterns and processes
Open this publication in new window or tab >>Arctic fox Vulpes lagopus population structure: circumpolar patterns and processes
Show others...
2011 (English)In: Oikos, ISSN 0030-1299, E-ISSN 1600-0706, Vol. 120, no 6, 873-885 p.Article in journal (Refereed) Published
Abstract [en]

Movement is a prominent process shaping genetic population structure. In many northern mammal species, population structure is formed by geographic distance, geographical barriers and various ecological factors that influence movement over the landscape. The Arctic fox Vulpes lagopus is a highly mobile, opportunistic carnivore of the Arctic that occurs in two main ecotypes with different ecological adaptations. We assembled microsatellite data in 7 loci for 1834 Arctic foxes sampled across their entire distribution to describe the circumpolar population structure and test the impact of (1) geographic distance, (2) geographical barriers and (3) ecotype designation on the population structure. Both Structure and Geneland demonstrated distinctiveness of Iceland and Scandinavia whereas low differentiation was observed between North America-northern Greenland, Svalbard and Siberia. Genetic differentiation was significantly correlated to presence of sea ice on a global scale, but not to geographical distance or ecotype designation. However, among areas connected by sea ice, we recorded a pattern of isolation by distance. The maximum likelihood approach in Migrate suggested that connectivity across North America-northern Greenland and Svalbard was particularly high. Our results demonstrate the importance of sea ice for maintaining connectivity between Arctic fox populations and we therefore predict that climate change will increase genetic divergence among populations in the future.

National Category
Biological Sciences
Research subject
Animal Ecology
Identifiers
urn:nbn:se:su:diva-43525 (URN)10.1111/j.1600-0706.2010.18766.x (DOI)000290871400009 ()
Available from: 2010-10-19 Created: 2010-10-19 Last updated: 2017-12-12
2. Pulses of movement cause temporal genetic shifts in the High Arctic
Open this publication in new window or tab >>Pulses of movement cause temporal genetic shifts in the High Arctic
Show others...
(English)Manuscript (preprint) (Other academic)
National Category
Biological Sciences
Research subject
Animal Ecology
Identifiers
urn:nbn:se:su:diva-43526 (URN)
Available from: 2010-10-19 Created: 2010-10-19 Last updated: 2017-02-25
3. Population structure in an isolated Arctic fox, Vulpes lagopus, population: the impact of geographical barriers
Open this publication in new window or tab >>Population structure in an isolated Arctic fox, Vulpes lagopus, population: the impact of geographical barriers
2009 (English)In: Biological Journal of the Linnean Society, ISSN 0024-4066, E-ISSN 1095-8312, Vol. 97, no 1, 18-26 p.Article in journal (Refereed) Published
Abstract [en]

The genetic composition of a population reflects several aspects of the organism and its environment. The Icelandic Arctic fox population exceeds 8000 individuals and is comprised of both coastal and inland foxes. Several factors may affect within-population movement and subsequent genetic population structure. A narrow isthmus and sheep-proof fences may prevent movement between the north-western and central part and glacial rivers may reduce movement between the eastern and central part of Iceland. Moreover, population density and habitat characteristics can influence movement behaviour further. Here, we investigate the genetic structure in the Icelandic Arctic fox population (n = 108) using 10 microsatellite loci. Despite large glacial rivers, we found low divergence between the central and eastern part, suggesting extensive movement between these areas. However, both model- and frequency-based analyses suggest that the north-western part is genetically differentiated from the rest of Iceland (F-ST = 0.04, D-S = 0.094), corresponding to 100-200 generations of complete isolation. This suggests that the fences cannot be the sole cause of divergence. Rather, the isthmus causes limited movement between the regions, implying that protection in the Hornstrandir Nature Reserve has a minimal impact on Arctic fox population size in the rest of Iceland. (C) 2009 The Linnean Society of London, Biological Journal of the Linnean Society, 2009, 97, 18-26.

Keyword
coastel, dispersal, divergence, genetic variation, Iceland, inland, isthmus, microsatellites, substructure
National Category
Biological Sciences
Research subject
Animal Ecology
Identifiers
urn:nbn:se:su:diva-29704 (URN)10.1111/j.1095-8312.2009.01172.x (DOI)000265406800002 ()0024-4066 (ISBN)
Available from: 2009-09-10 Created: 2009-09-10 Last updated: 2017-12-13
4. Farmed arctic foxes on the Fennoscandian mountain tundra: implications for conservation
Open this publication in new window or tab >>Farmed arctic foxes on the Fennoscandian mountain tundra: implications for conservation
Show others...
2009 (English)In: Animal Conservation, ISSN 1367-9430, E-ISSN 1469-1795, Vol. 12, no 5, 434-444 p.Article in journal (Refereed) Published
Abstract [en]

Hybridization between wild and captive-bred individuals is a serious conservation issue that requires measures to prevent negative effects. Such measures are, however, often considered controversial by the public, especially when concerning charismatic species. One of the threats to the critically endangered Fennoscandian arctic fox Alopex lagopus is hybridization with escaped farm foxes, conveying a risk of outbreeding depression through loss of local adaptations to the lemming cycle. In this study, we investigate the existence of escaped farm foxes among wild arctic foxes and whether hybridization has occurred in the wild. We analysed mitochondrial control region sequences and 10 microsatellite loci in samples from free-ranging foxes and compared them with reference samples of known farm foxes and true Fennoscandian arctic foxes. We identified the farm fox specific mitochondrial haplotype H9 in 25 out of 182 samples, 21 of which had been collected within or nearby the wild subpopulation on Hardangervidda in south-western Norway. Genetic analyses of museum specimens collected on Hardangervidda (1897–1975) suggested that farm fox genotypes have recently been introduced to the area. Principal component analysis as well as both model- and frequency-based analyses of microsatellite data imply that the free-ranging H9s were farm foxes rather than wild arctic foxes and that the entire Hardangervidda population consisted of farm foxes or putative hybrids. We strongly recommend removal of farm foxes and hybrids in the wild to prevent genetic pollution of the remaining wild subpopulations of threatened arctic foxes.

Keyword
hybridization, genetic pollution, outbreeding depression, Alopex lagopus, captive
National Category
Biological Sciences
Research subject
Animal Ecology
Identifiers
urn:nbn:se:su:diva-29064 (URN)10.1111/j.1469-1795.2009.00269.x (DOI)000270140600008 ()
Available from: 2009-08-10 Created: 2009-08-10 Last updated: 2017-12-13
5. From monogamy to complexity: Arctic fox social organization
Open this publication in new window or tab >>From monogamy to complexity: Arctic fox social organization
Show others...
(English)Manuscript (preprint) (Other academic)
National Category
Biological Sciences
Research subject
Animal Ecology
Identifiers
urn:nbn:se:su:diva-43527 (URN)
Available from: 2010-10-19 Created: 2010-10-19 Last updated: 2017-02-25

Open Access in DiVA

No full text

Search in DiVA

By author/editor
Norén, Karin
By organisation
Department of Zoology
Biological Sciences

Search outside of DiVA

GoogleGoogle Scholar

isbn
urn-nbn

Altmetric score

isbn
urn-nbn
Total: 444 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf