Data from: Evolutionarily accelerated invasions: the rate of dispersal evolves upwards during the range advance of cane toads

Human activities are changing habitats and climates, and causing species' ranges to shift. Range expansion brings into play a set of powerful evolutionary forces at the expanding range edge that act to increase dispersal rates. One likely consequence of these forces is accelerating rates of range advance due to evolved increases in dispersal on the range edge. In northern Australia, cane toads have increased their rate of spread five-fold in the last 70 years. Our breeding trials with toads from populations spanning the species' invasion history in Australia suggest a genetic basis to dispersal rates, and interpopulation genetic variation in such rates. Toads whose parents were from the expanding range front dispersed faster than toads whose parents were from the core of the range. This difference reflects patterns found in their field-collected mothers and fathers, and points to heritable variance in the traits that have accelerated the toads' rate of invasion across tropical Australia over recent decades. Taken together with demonstrated spatial assortment by dispersal ability occurring on the expanding front, these results point firmly to ongoing evolution as a driving force in the accelerated expansion of toads across northern Australia.人类活动正改变着生境与气候，致使物种种群分布范围发生位移。分布范围的扩张会在扩张前沿激活一系列强大的进化动力，这些动力可提升物种的扩散速率。这类进化动力的一个潜在结果，便是因分布前沿扩散能力的演化提升，而导致种群扩张速度加快。在澳大利亚北部，甘蔗蟾蜍（cane toads）的扩散速率在过去70年间提升了5倍。我们针对取自澳大利亚境内不同入侵阶段蟾蜍种群的繁育实验表明，扩散速率存在遗传基础，且不同种群间的扩散速率存在遗传差异。亲本来自分布扩张前沿的蟾蜍，其扩散速度快于亲本来自分布范围核心区域的蟾蜍。该差异与野外采集的蟾蜍亲本所呈现的模式一致，表明近几十年来驱动澳大利亚热带地区蟾蜍入侵速率加快的相关性状，存在可遗传的变异。结合此前已证实的、在扩张前沿发生的基于扩散能力的空间分选现象，本研究结果明确指出，持续发生的演化是推动澳大利亚北部甘蔗蟾蜍种群快速扩张的核心动力。