Data from: Rapid adaptation to climate facilitates range expansion of an invasive plant

Adaptation to climate, evolving over contemporary time scales, could facilitate rapid range expansion across environmental gradients. Here, we examine local adaptation along a climatic gradient in the North American invasive plant Lythrum salicaria. We show that the evolution of earlier flowering is adaptive at the northern invasion front where it increases fitness as much as, or more than, the effects of enemy release and the evolution of increased competitive ability. However, early flowering decreases investment in vegetative growth, which reduces fitness by a factor of 3 in southern environments where the North American invasion commenced. Our results demonstrate that local adaptation can evolve quickly during range expansion, overcoming environmental constraints on propagule production.

在当代时间尺度上演化的气候适应性，可助力物种快速跨越环境梯度实现分布范围扩张。本研究以北美入侵植物千屈菜（Lythrum salicaria）为研究对象，探究其沿气候梯度的本地适应性演化。研究发现，开花时间提前的演化在入侵北部前沿具有适应性意义：其对适合度的提升幅度，至少不低于天敌逃逸效应与竞争能力提升演化的作用效果。但开花提前会降低营养生长的资源投入，在北美入侵起源的南部生境中，这会使适合度下降至原来的1/3。本研究结果表明，在分布范围扩张过程中，本地适应性可快速演化，从而突破繁殖体生产所受的环境限制。