Paleoecology meets genetics: deciphering past vegetational dynamics

Genetic analysis adds a novel dimension to paleoecology that is becoming increasingly important for elucidating vegetational dynamics in relation to climate change. Because past vegetational changes have often left distinct genetic imprints on current plant populations, genetic analysis can add detail to fossil-based reconstructions. Recent surveys of DNA polymorphisms yield new insights into past vegetational changes and address long-standing paleoecological questions. These studies reveal that small tree populations survived in mid-to high-latitude refugia throughout the Quaternary glacial episodes. They further reveal migration pathways and demographic processes during postglacial range expansion. These results challenge previous notions regarding tree species responses to climate change and help to identify genetic conservation targets. Here, we review these recent advances and outline research prospects at the interface between paleoecology and genetics.