Population history and genetic structure of a circumpolar species: the arctic fox

Abstract

The circumpolar arctic fox Alopex lagopus thrives in cold climates and has a high migration rate involving long‐distance movements. Thus, it differs from many temperate taxa that were subjected to cyclical restriction in glacial refugia during the Ice Ages. We investigated population history and genetic structure through mitochondrial control region variation in 191 arctic foxes from throughout the arctic. Several haplotypes had a Holarctic distribution and no phylogeographical structure was found. Furthermore, there was no difference in haplotype diversity between populations inhabiting previously glaciated and unglaciated regions. This suggests current gene flow among the studied populations, with the exception of those in Iceland, which is surrounded by year‐round open water. Arctic foxes have often been separated into two ecotypes: ‘lemming’ and ‘coastal’. An analysis of molecular variance suggested particularly high gene flow among populations of the ‘lemming’ ecotype. This could be explained by their higher migration rate and reduced fitness in migrants between ecotypes. A mismatch analysis indicated a sudden expansion in population size around 118 000 BP, which coincides with the last interglacial. We propose that glacial cycles affected the arctic fox in a way opposite to their effect on temperate species, with interglacials leading to short‐term isolation in northern refugia. © 2005 The Linnean Society of London, Biological Journal of the Linnean Society, 2005, 84, 79–89.

Glacial survival of trophically linked boreal species in northern Europe

“…However, contrary to what has been suggested for other cold-adapted species (e.g. [55]), the range of G. intermedia was probably not larger during glacial episodes. In fact, SDM analyses suggested an overall reduced range for this species at the LGM, with northern Europe and the Carpathians populations experiencing contraction.…”

Rabies in the Arctic Fox Population, Svalbard, Norway

“…Arctic foxes are able to migrate extremely long distances (Tarroux et al, 2010). Genetic studies show that a high gene flow, due to frequent long-distance foraging movements, has resulted in a panmitic circumpolar population of arctic foxes (Dalé n et al, 2005;Charmichael et al, 2007;Geffen et al, 2007) and that the occurrence of sea ice is likely the most important factor in explaining the genetic variation of Arctic fox populations in high Arctic islands (Geffen et al, 2007). The archipelago of Svalbard may be a closed entity for the arctic fox during summer but, during winter, these islands are normally surrounded by pack ice, enabling foxes to migrate between Svalbard and, for example, Novaja Semlja, Russia (Fuglei and Øritsland, 2003) or other Arctic tundra areas in Russia (Noré n et al, 2011).…”

Genetic structuring in three closely related circumpolar plant species: AFLP versus microsatellite markers and high-arctic versus arctic–alpine distributions

“…High dispersal potential and recent bottlenecks have been suggested as an explanation for the low levels of genetic structuring in high-arctic animal species (Paetkau et al, 1999;Dalén et al, 2005;Marthinsen et al, 2008). In arctic plants, much higher levels of long-distance dispersal than traditionally thought have recently been demonstrated for several species, probably facilitated by wind over frozen sea ice, by driftwood or by birds (Alsos et al, 2007).…”