Chappell Mark, Odell Jason
Biology Department, University of California, Riverside, CA 92521, USA.
Physiol Biochem Zool. 2004 Jan-Feb;77(1):27-38. doi: 10.1086/378920.
We measured maximal oxygen consumption (VO(2max)) and burst speed in populations of Trinidadian guppies (Poecilia reticulata) from contrasting high- and low-predation habitats but reared in "common garden" conditions. We tested two hypothesis: first, that predation, which causes rapid life-history evolution in guppies, also impacts locomotor physiology, and second, that trade-offs would occur between burst and aerobic performance. VO(2max) was higher than predicted from allometry, and resting VO(2) was lower than predicted. There were small interdrainage differences in male VO(2max), but predation did not affect VO(2max) in either sex. Maximum burst speed was correlated with size; absolute burst speed was higher in females, but size-adjusted speed was greater in males. For both sexes, burst speed conformed to allometric predictions. There were differences in burst speed between drainages in females, but predation regime did not affect burst speed in either sex. We did not find a significant correlation between burst speed and VO(2max), suggesting no trade-off between these traits. These results indicate that predation-mediated evolution of guppy life history does not produce concomitant evolution in aerobic capacity and maximum burst speed. However, other aspects of swimming performance (response latencies or acceleration) might show adaptive divergence in contrasting predation regimes.
我们测量了来自特立尼达孔雀鱼（Poecilia reticulata）不同高捕食和低捕食栖息地种群的最大耗氧量（VO₂max）和爆发速度，这些孔雀鱼是在“共同花园”条件下饲养的。我们测试了两个假设：第一，捕食会导致孔雀鱼快速的生活史进化，同时也会影响运动生理学；第二，爆发性能和有氧性能之间会出现权衡。VO₂max高于根据异速生长预测的值，而静息VO₂低于预测值。雄性VO₂max存在小的流域间差异，但捕食对两性的VO₂max均无影响。最大爆发速度与体型相关；雌性的绝对爆发速度更高，但体型调整后的速度雄性更快。对于两性来说，爆发速度均符合异速生长预测。雌性在不同流域间爆发速度存在差异，但捕食方式对两性的爆发速度均无影响。我们没有发现爆发速度和VO₂max之间存在显著相关性，这表明这些性状之间不存在权衡。这些结果表明，捕食介导的孔雀鱼生活史进化不会导致有氧能力和最大爆发速度的同步进化。然而，游泳性能的其他方面（反应潜伏期或加速度）在不同的捕食方式下可能会表现出适应性差异。
