Adaptation to seasonal drought in Arabis alpina is linked to the demographic history and climatic changes since the last glacial maximum

Description

Bastiaan Tjeng and colleagues sequenced genomes from hundreds of alpine plants in 2026 to trace how one species adapted to dry summers. The perennial herb grows across cold mountain regions, yet populations in northern Spain face warm, dry summers unlike the usual habitat. The team read genomes from plants across Europe and rebuilt the species' past movements and population sizes, then searched for genes under selection linked to stress and growth.

Their history points to a spread from near the Alps into Spain long before the last ice age, with large populations during glacial times. In the warmer period since, populations split apart and lost diversity. Selected genes tied to drought response and growth control stood out in Spanish plants. An old variant affecting flowering also seemed to help with dry conditions. The authors credit a mix of old variation and new mutations for the adaptation.

Catalog record

Source: https://europepmc.org/articles/PMC13551622