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

Arabis alpina populations in Northern Spain show genetic divergence and adaptation to drought, driven by demographic history and climatic shifts since the last glacial maximum.

• Why it matters: Understanding how species adapt to changing environments is crucial for predicting responses to climate change, especially in Arctic-alpine plants facing increasing drought stress.
• What they did: Sequencing 426 genomes of A. alpina revealed demographic events starting 216 kya, with ancient divergence, population fragmentation, and signatures of selection at stress-response genes, including drought-related ones.
• The result: Findings indicate that ancestral genetic variation and positive selection on drought-response genes enable adaptation, informing how plants evolve traits to cope with climate change.