Combining palaeodistribution modelling and phylogeographical approaches for identifying glacial refugia in Alpine Primula

Abstract

Aim We investigated the late Quaternary history of two closely related and partly sympatric species of Primula from the south‐western European Alps, P. marginata Curtis and P. latifolia Lapeyr., by combining phylogeographical and palaeodistribution modelling approaches. In particular, we were interested in whether the two approaches were congruent and identified the same glacial refugia. Location South‐western European Alps. Methods For the phylogeographical analysis we included 352 individuals from 28 populations of P. marginata and 172 individuals from 15 populations of P. latifolia and used amplified fragment length polymorphisms (AFLPs). For palaeodistribution modelling, species distribution models (SDMs) were based on extant species occurrences and then projected to climate models (CCSM, MIROC) of the Last Glacial Maximum (LGM), c. 21 ka. Results The locations of the modelled LGM refugia were supported by various indices of genetic variation. The refugia of the two species were largely geographically isolated, overlapping only 6–11% of the species' total LGM distribution. This overlap decreased when the position of the glacial ice sheet and the differential elevational and edaphic distributions of the two species were considered. Main conclusions The combination of phylogeography and palaeodistribution modelling proved useful in locating putative glacial refugia of the two alpine species of Primula. The phylogeographical data allowed us to identify those parts of the modelled LGM refugial area that were likely source areas for recolonization. The use of SDMs predicted LGM refugial areas substantially larger and geographically more divergent than could have been predicted by phylogeographical data alone.

Glacial refugia, recolonization patterns and diversification forces in Alpine‐endemic Megabunus harvestmen

“…Populations in putative refugia have a higher diversity than in recolonized areas (Schorr et al . ), as observed here in the southern populations (Fig. S13, Supporting information).…”

Phylogeography of the land snail genus Orcula(Orculidae, Stylommatophora) with emphasis on the Eastern Alpine taxa: speciation, hybridization and morphological variation

“…Moreover, the current distributions of all Alpine endemic Orcula species include areas not covered by ice during the LGM (Figure 9). The existence of Eastern Alpine refuges is also supported by several recent molecular genetic studies dealing with mountain plants [8,37,38] and invertebrates [9,10,39]. Besides, the Eastern Alpine margins harbor several endemic species with low active dispersal capabilities, among those blind troglobiotic beetles [40] and endemic land snail species restricted to high altitudes [41].…”

Genetic consequences of Quaternary climatic oscillations in the Himalayas: Primula tibetica as a case study based on restriction site‐associated DNA sequencing

“…It has recently been proposed that mountain uplift can also result in divergence and speciation in the face of gene flow across a continuous altitudinal gradient (Filatov et al ., ). In this context, climatic oscillations during the Quaternary could have reinforced allopatric divergence and driven intraspecific divergence as well as local adaptation (Davis & Shaw, ; Hewitt, ; Li et al ., ; Liu et al ., ; Schorr et al ., ), as populations experienced repeated cycles of retreat to refugia and postglacial expansions (Abbott et al ., ; Avise, ; Petit et al ., ). The demographic changes involved in these range shifts affected the spatial patterns of genetic variation within and among populations (Hewitt, ).…”