Glacial allopatry vs. postglacial parapatry and peripatry: the case of hedgehogs

Abstract

Although hedgehogs are well-known examples of postglacial recolonisation, the specific processes that shape their population structures have not been examined by detailed sampling and fast-evolving genetic markers in combination with model based clustering methods. This study aims to analyse the impacts of isolation within glacial refugia and of postglacial expansion on the population structure of the Northern White-breasted hedgehog (Erinaceus roumanicus). It also discusses the role of the processes at edges of species distribution in its evolutionary history. The maternally inherited mitochondrial control region and the bi-parentally inherited nuclear microsatellites were used to examine samples within the Central Europe, Balkan Peninsula and adjacent islands. Bayesian coalescent inference and neutrality tests proposed a recent increase in the population size. The most pronounced pattern of population structure involved differentiation of the insular populations in the Mediterranean Sea and the population within the contact zone with E. europaeus in Central Europe. An interspecies hybrid was detected for the first time in Central Europe. A low genetic diversity was observed in Crete, while the highest genetic distances among individuals were found in Romania. The recent population in the post-refugial area related to the Balkan Peninsula shows a complex pattern with pronounced subpopulations located mainly in the Pannonian Basin and at the Adriatic and Pontic coasts. Detailed analyses indicate that parapatry and peripatry may not be the only factors that limit range expansion, but also strong microevolutionary forces that may change the genetic structure of the species. Here we present evidence showing that population differentiation may occur not only during the glacial restriction of the range into the refugia, but also during the interglacial range expansion. Population differentiation at the Balkan Peninsula and adjacent regions could be ascribed to diversification in steppe/forest biomes and complicated geomorphology, including pronounced geographic barriers as Carpathians.

Application of a SSR‐GBS marker system on investigation of European Hedgehog species and their hybrid zone dynamics

“…Regardless, hedgehogs are species that are potentially impacted by fragmentation of their habitat by human infrastructures, roadways potentially being the most significant barriers for gene flow and migration (Huijser & Bergers, 2000;Orlowski & Nowak, 2004). These hedgehog species have a moderate genetic structure, and on a larger scale, they show an isolation by distance pattern that is likely a consequence of recolonization after the last glaciation period (Bolfíková et al, 2017;Seddon et al, 2001). However, it has been verified that on small spatial scales the isolation by distance pattern can be disturbed due to habitat fragmentation and anthropogenic barriers to gene flow (Becher and Griffiths 1998), hence the importance of studying the genetic variation of these species in restricted geographical scales (Braaker, Kormann, Bontadina, & Obrist, 2017).…”

3D Geometric Morphometrics Reveals Convergent Character Displacement in the Central European Contact Zone between Two Species of Hedgehogs (Genus Erinaceus)

“…Considering the low frequency of interspecific hybridisation (one backcrossed individual out of 210 tested in Czechia and Slovakia) [ 3 , 4 ], species determination based on phenotypes has been confirmed by sequencing the mitochondrial control region in the samples originating from the zone of sympatry (N = 27). The tissue was collected in the course of skull preparation, and fixed in 96% ethanol, prior to storage at −20 °C.…”

“…There has been little gene flow between E. europaeus and E. roumanicus [ 3 , 4 , 5 ]. Alongside genetic differentiation, there is a divergence of phenotypic traits in the closely related species which is an important source of information about adaptive processes, i.a.…”

High Genetic Diversity among Breeding Red-Backed Shrikes Lanius collurio in the Western Palearctic

“…These severe glacial episodes forced biota to retreat to southern refugia [6,7], which implied admixing of populations. Subsequently, after the retreat of the ice cap, populations expanded and recolonized the northern latitudes [8,9]. This complex process of post-glacial population expansion northward from the southern refugia occurred at least 30 times during the Pleistocene [3] and was in strong interdependence with the vegetation availability [10].…”