PDF(Pubmed)
Abstract：
Understanding how environmental factors affect the performance of predators can provide profound insights into predator-prey interactions from evolutionary and ecological perspectives and the global distributional patterns of each taxon. Almost all venomous predators are ectotherms, with muscle contraction properties depending on temperature. For predators having venom transportation systems driven by muscle contraction, temperature may have quite large effects on envenomation performance for prey subjugation. Here, we used videography and enzyme-linked immunosorbent assay to examine thermal effects on envenomation kinematics and venom expenditure in predatory strikes of a venomous snake, the Mamushi Gloydius blomhoffii, to its main rodent prey at various body temperatures under both field and laboratory experimental conditions. Unexpectedly, we found that the thermal effects on envenomation performance are limited over nearly the entire ecologically relevant range of temperature (from 13.2°C to 26.2°C). Although temperature statistically significantly affected the mass of venom injected under field conditions, temperature explained only a minor proportion of the variation in venom expenditure. These findings suggest that the Mamushi is able to maintain prey subjugation performance across a wide range of temperatures, which is highly advantageous for ectothermic predators. Further studies should examine the underlying mechanisms of the limited thermal effects and their ubiquity across venomous predators.
摘要：
了解环境因素如何影响捕食者的表现，可以从进化和生态角度以及每个分类单元的全球分布模式为捕食者与猎物的相互作用提供深刻的见解。几乎所有有毒的捕食者都是异温动物，肌肉收缩特性取决于温度。对于具有由肌肉收缩驱动的毒液运输系统的捕食者，温度可能对猎物捕食的捕毒性能有相当大的影响。这里,我们使用摄像和酶联免疫吸附试验来检查毒蛇的捕食性对毒液运动学和毒液消耗的热效应，MamushiGloyydiusblomhofii,在野外和实验室实验条件下，在不同的体温下，它的主要啮齿动物猎物。出乎意料的是,我们发现，在几乎整个生态相关的温度范围内（从13.2°C到26.2°C），对麻醉性能的热效应都受到限制。尽管温度在统计上显着影响野外条件下注射的毒液的质量，温度仅解释了毒液支出变化的一小部分。这些发现表明，Mamushi能够在很宽的温度范围内保持猎物的征服性能，这对放热捕食者非常有利。进一步的研究应该检查有限的热效应的潜在机制及其在有毒捕食者中的普遍性。
