Ancient mitochondrial DNA and the genetic history of Eurasian beaver (Castor fiber) in Europe

Abstract

After centuries of human hunting, the Eurasian beaver Castor fiber had disappeared from most of its original range by the end of the 19th century. The surviving relict populations are characterized by both low genetic diversity and strong phylogeographical structure. However, it remains unclear whether these attributes are the result of a human-induced, late Holocene bottleneck or already existed prior to this reduction in range. To investigate genetic diversity in Eurasian beaver populations during the Holocene, we obtained mitochondrial control region DNA sequences from 48 ancient beaver samples and added 152 modern sequences from GenBank. Phylogeographical analyses of the data indicate a differentiation of European beaver populations into three mitochondrial clades. The two main clades occur in western and eastern Europe, respectively, with an early Holocene contact zone in eastern Europe near a present-day contact zone. A divergent and previously unknown clade of beavers from the Danube Basin survived until at least 6000 years ago, but went extinct during the transition to modern times. Finally, we identify a recent decline in effective population size of Eurasian beavers, with a stronger bottleneck signal in the western than in the eastern clade. Our results suggest that the low genetic diversity and the strong phylogeographical structure in recent beavers are artefacts of human hunting-associated population reductions. While beaver populations have been growing rapidly since the late 19th century, genetic diversity within modern beaver populations remains considerably reduced compared to what was present prior to the period of human hunting and habitat reduction.

Nuclear and mitochondrial genetic structure in the Eurasian beaver (Castor fiber) – implications for future reintroductions

“…A recent study of ancient mtDNA by Horn et al. () has indeed demonstrated that strong apparent phylogeographic structuring in Eurasian beaver has arisen as a result of the population bottlenecks, although they suggest that eastern and western ESUs are maintained. This analysis both examines the original samples of Durka et al.…”

“…; Horn et al. ). Most recent common ancestor for the two clades has been estimated to be 210 000 (110 000–340 000) years old (Horn et al.…”

Allometry of the skull in one autochthonous and two reintroduced populations of Eurasian beavers (Castor fiber, Castoridae, Rodentia)

“…All three of the surveyed populations were genetically closely related (Horn et al, 2014). Such taxonomy is also supported by single nucleotide polymorphisms (SNPs) recently studied for autochthonous and reintroduced populations of C. fiber by Senn et al (2014).…”

“…All studied populations are genetically close and belonging to the Eastern mitochondrial haplotypes clade (Horn et al, 2014;Senn et al, 2014).…”

Hair, Bone Plates and Coprolites: Ancient DNA Research on Rare Archaeological Materials

“…The focus of the research has been several wild mammal, bird, reptile and fish species (e.g. Sommer et al 2009;Fraser et al 2012;Bray et al 2013;Herman et al 2014;Horn et al 2014;Nikulina, Schmölcke 2015a, 2015b, as well as domestic cattle, pigs and dogs (Nikulina, Schmölcke 2008Scheu et al 2008;Krause-Kyora et al 2013;Zhilin et al 2014;Niemi et al 2015). In particular, the genetic analysis of well-preserved teeth and bones to identify the species, the so-called DNA bar-coding, is reasonably priced and can be undertaken, for instance, in cooperation with the Centre for Baltic and Scandinavian Archaeology (ZBSA) in Schleswig, Germany, with its specialised laboratory for ancient animal DNA (Nikulina, Schmölcke 2010).…”