Molecular evidence for glacial refugia of mountain plants in the European Alps

TLDR

Many mountain ranges have been strongly glaciated during the Quaternary ice ages, and the locations of glacial refugia of mountain plants have been debated for a long time. A series of detailed molecular studies investigating intraspecific genetic variation of mountain plants in the European Alps now allows for a first synopsis. The authors examined intraspecific genetic variation across multiple alpine species to infer phylogeographic patterns. Phylogeographic patterns, compared with geological and palaeoenvironmental data, reveal glacial refugia along the southwestern, southern, eastern, and northern borders of the Alps, with additional refugia in central alpine areas where high‑elevation plants survived on ice‑free mountain tops, and these patterns align with known centres of Alpine species diversity and endemism, indicating that climatic fluctuations similarly shape gene and species diversity.

Abstract

Abstract Many mountain ranges have been strongly glaciated during the Quaternary ice ages, and the locations of glacial refugia of mountain plants have been debated for a long time. A series of detailed molecular studies, investigating intraspecific genetic variation of mountain plants in the European Alps, now allows for a first synopsis. A comparison of the phylogeographic patterns with geological and palaeoenvironmental data demonstrates that glacial refugia were located along the southwestern, southern, eastern and northern border of the Alps. Additional glacial refugia were present in central Alpine areas, where high‐elevation plants survived the last glaciation on ice‐free mountain tops. The observed intraspecific phylogeographies suggest general patterns of glacial survival, which conform to well‐known centres of Alpine species diversity and endemism. This implies that evolutionary or biogeographic processes induced by climatic fluctuations act on gene and species diversity in a similar way.