Genetic structure of fragmented populations of red squirrel (Sciurus vulgaris) in the UK

Abstract

The relationships among 207 squirrels from 12 locations in the UK and three in mainland Europe were examined using mitochondrial DNA (mtDNA) control region sequence. Twenty-six haplotypes were detected, many of which were population specific. Eighty per cent of the populations analysed contained two or more haplotypes. Hierarchical analysis of molecular variance showed the majority of genetic variation to be partitioned among populations. Genetic diversity varied considerably within the UK, and conformed to no obvious geographical trend. The populations in Argyll and Spadeadam Forest showed the highest levels of variation in the UK. However, the greatest genetic diversity was seen in Bavaria, southern Germany where six unique alleles were detected in a sample of 10 individuals. Phylogenetic analysis revealed no evolutionary divergence between UK and mainland European haplotypes. We conclude that, within the UK, the genetic patterns observed are most likely to be explained by the effects of genetic drift which has occurred since the isolation of populations during the past few hundred years, hence we cannot detect any underlying phylogeographic pattern. Therefore, the use of larger, geographically distinct populations within the UK for augmentation of small isolated populations is unlikely to pose problems of genetic incompatibility. Further, the role that demographic factors may have in complicating the application of current genetically based management unit criteria is likely to need further attention.

Phylogeography of Barbary macaques ( Macaca sylvanus ) and the origin of the Gibraltar colony

“…These patterns are reinforced by the marked philopatric nature of female macaques, causing sharp geographical clustering of mtDNA haplotypes (3). Low levels of control region diversity have been seen not only in species with pronounced female philopatry, but also in species known to have undergone population bottlenecks in the recent past (39)(40)(41). It has also been argued that reduced genetic variability in M. sylvanus compared with other macaques might be the result of successive bottlenecks during withdrawal from a wider Pleistocene expansion to contemporary areas of dispersal (42).…”

Molecular Systematics of the Western Rattlesnake, Crotalus viridis (Viperidae), with Comments on the Utility of the D-Loop in Phylogenetic Studies of Snakes

“…Studies of other vertebrates have often used the D-loop region because of its extreme variability (e.g., Barratt et al, 1999;Doukakis et al, 1999;Nesbo et al, 1999;Steinfartz et al, 2000;Terry et al, 2000;Vila et al, 1997). This study is one of the first to use the D-loop region to construct phylogenetic relationships for snakes.…”

Origin of, and conservation units in, the Irish red squirrel (Sciurus vulgaris) population

“…However, phylogenetic analysis of the red squirrel population in Britain found no clear differentiation between British and mainland European populations (Barratt et al 1999;Hale et al 2004), and there is increasing evidence that British lineages are being rapidly replaced by lineages from recent translocations from mainland Europe (Hale et al 2004). This would suggest that the British population would not be useful in tracking postglacial colonisation routes of Britain.…”