Hillman Stanley S, Drewes Robert C, Hedrick Michael S, Hancock Thomas V
Department of Biology, Portland State University, Portland, OR 97201, USA
Department of Herpetology, California Academy of Sciences, San Francisco, CA 94118, USA.
J Exp Biol. 2014 Sep 15;217(Pt 18):3356-64. doi: 10.1242/jeb.105908. Epub 2014 Jul 10.
Vagility is the inherent power of movement by individuals. Vagility and the available duration of movement determine the dispersal distance individuals can move to interbreed, which affects the fine-scale genetic structure of vertebrate populations. Vagility and variation in population genetic structure are normally explained by geographic variation and not by the inherent power of movement by individuals. We present a new, quantitative definition for physiological vagility that incorporates aerobic capacity, body size, body temperature and the metabolic cost of transport, variables that are independent of the physical environment. Physiological vagility is the speed at which an animal can move sustainably based on these parameters. This meta-analysis tests whether this definition of physiological vagility correlates with empirical data for maximal dispersal distances and measured microsatellite genetic differentiation with distance {[F(ST)/[1-F(ST))]/ln distance} for amphibians, reptiles, birds and mammals utilizing three locomotor modes (running, flying, swimming). Maximal dispersal distance and physiological vagility increased with body mass for amphibians, reptiles and mammals utilizing terrestrial movement. The relative slopes of these relationships indicate that larger individuals require longer movement durations to achieve maximal dispersal distances. Both physiological vagility and maximal dispersal distance were independent of body mass for flying vertebrates. Genetic differentiation with distance was greatest for terrestrial locomotion, with amphibians showing the greatest mean and variance in differentiation. Flying birds, flying mammals and swimming marine mammals showed the least differentiation. Mean physiological vagility of different groups (class and locomotor mode) accounted for 98% of the mean variation in genetic differentiation with distance in each group. Genetic differentiation with distance was not related to body mass. The physiological capacity for movement (physiological vagility) quantitatively predicts genetic isolation by distance in the vertebrates examined.
迁移能力是个体固有的运动能力。迁移能力和可利用的运动持续时间决定了个体为进行杂交而能够移动的扩散距离，这会影响脊椎动物种群的精细尺度遗传结构。迁移能力和种群遗传结构的变化通常用地理差异来解释，而非个体固有的运动能力。我们提出了一个新的、关于生理迁移能力的定量定义，该定义纳入了有氧能力、体型、体温和运输代谢成本等与物理环境无关的变量。生理迁移能力是动物基于这些参数能够持续移动的速度。这项荟萃分析检验了生理迁移能力的这一定义是否与两栖动物、爬行动物、鸟类和哺乳动物利用三种运动模式（奔跑、飞行、游泳）的最大扩散距离的实证数据以及测量的微卫星遗传分化与距离{[F(ST)/[1 - F(ST))]/ln距离}相关。对于利用陆地运动的两栖动物、爬行动物和哺乳动物，最大扩散距离和生理迁移能力随体重增加而增加。这些关系的相对斜率表明，体型较大的个体需要更长的运动持续时间才能达到最大扩散距离。对于飞行脊椎动物，生理迁移能力和最大扩散距离均与体重无关。陆地运动的遗传分化随距离变化最大，两栖动物的分化均值和方差最大。飞行鸟类、飞行哺乳动物和海洋游泳哺乳动物的分化最小。不同组（纲和运动模式）的平均生理迁移能力占每组遗传分化随距离变化均值的98%。遗传分化随距离变化与体重无关。在所研究的脊椎动物中，运动的生理能力（生理迁移能力）定量预测了距离导致的遗传隔离。
