Evolution under changing climates: climatic niche stasis despite rapid evolution in a non-native plant.

Area of Science:

• Evolutionary biology
• Ecology
• Climate change adaptation

Background:

• Understanding the genetic capacity of populations to adapt to rapid climate change is crucial.
• Evolution of life-history events, such as flowering phenology, is a key adaptive response.
• Experimental studies on rapid adaptation are challenging.

Purpose of the Study:

• To investigate the genetic adaptation of non-native Lactuca serriola to changing climates.
• To determine if invasive populations can evolve to fill climatic niches.
• To explore the evolution of flowering phenology in response to climate gradients.

Main Methods:

• Utilized molecular markers to trace the origin and admixture of invasive populations.
• Employed a common garden experiment to assess phenotypic plasticity and evolution.
• Applied climatic niche modeling to compare native and introduced ranges.

Main Results:

• Non-native Lactuca serriola primarily originated from a European climatic subset of its native range.
• Invasive populations rapidly refilled their climatic niche, evolving flowering phenology along climate gradients.
• Some populations evolved to tolerate more extreme climates than their European origin, but not outside the species' broader native range.

Conclusions:

• Plant populations can adapt rapidly to climatic conditions already present within the species' broader native range.
• Evolutionary adaptation to conditions outside the species' established niche space is more challenging.
• These findings explain niche conservatism in many non-native species and highlight the limits of rapid adaptation.