Data from: Differentiation of movement behavior in an adaptively diverging salamander population

Dispersal is considered to be a species-specific trait, but intraspecific variation can be high. However, when and how this complex trait starts to differentiate during the divergence of species/lineages is unknown. Here, we studied the differentiation of movement behavior in a large salamander (Salamandra salamandra) population, in which individual adaptations to different habitat conditions drive the genetic divergence of this population into two subpopulations. In this system, salamanders have adapted to the deposition and development of their larvae in ephemeral ponds versus small first order streams. In general, the pond habitat is characterized as a spatially and temporally highly unpredictable habitat, while streams provide more stable and predictable conditions for the development of larvae. We analyzed the fine scale genetic distribution of larvae, and explored whether the adaptation to different larval habitat conditions has in turn also affected dispersal strategies and home range size of adult salamanders. Based on the genetic assignment of adult individuals to their respective larval habitat type, we show that pond-adapted salamanders occupied larger home ranges, displayed long distance dispersal and had a higher variability of movement types than the stream-adapted individuals. We argue that the differentiation of phenotypically plastic traits such as dispersal and movement characteristics can be a crucial component in the course of adaptation to new habitat conditions, thereby promoting the genetic divergence of populations.

扩散被视为物种的特异性性状，但种内变异程度往往较高。然而，这一复杂性状在物种/系统发育支系分化过程中何时开始分化，目前尚未明晰。本研究以大型火蝾螈（Salamandra salamandra）种群为研究对象，探讨其运动行为的分化机制；该种群中，个体对不同生境条件的适应，正推动该种群遗传分化为两个亚种群。在此研究系统中，该火蝾螈已适应将幼体安置在临时池塘或小型一级溪流中并完成发育。总体而言，池塘生境在空间与时间上均具有高度不可预测性，而溪流则为幼体发育提供更为稳定且可预测的环境条件。本研究分析了幼体的精细尺度遗传分布，并探讨了针对不同幼体生境的适应，是否反过来影响了成体火蝾螈的扩散策略与家域大小。基于成体个体的幼体生境类型遗传归属分析，本研究发现，相较于适应溪流生境的个体，适应池塘生境的火蝾螈拥有更大的家域范围，表现出更长距离的扩散行为，且运动类型的变异度更高。本研究认为，诸如扩散与运动特征这类表型可塑性性状（phenotypically plastic traits）的分化，是种群适应新生境过程中的关键组成部分，进而可推动种群的遗传分化。