Rapid adaptive evolution in restored populations of a perennial plant

Restored populations of Galium wirtgenii flowered earlier than semi-natural donor populations, with the difference persisting across three years in a common-garden test.

• Why it matters: Restoration sites differ from natural habitats, so success may depend on whether restored plant populations can adapt quickly to novel conditions. Rapid adaptive evolution during restoration is still rarely documented.
• What they did: Seeds from 571 mother plants from 48 restored and 18 semi-natural sites were grown in a common garden for three years, with a clipping treatment during full blossom to test regeneration after mowing.
• The result: Earlier flowering in restored sites persisted across all three years, consistent with a heritable response to earlier mowing, while early-life slower growth disappeared later, suggesting maternal effects rather than genetic differentiation. No regeneration differences after clipping were detected, implying limited fitness advantage.