Lastein Stine, Höglund Erik, Mayer Ian, Overli Oyvind, Døving Kjell B
Department of Molecular Biosciences, Faculty of Mathematics and Natural Sciences, University of Oslo, P.O. Box. 1041, Blindern, 0316 Oslo, Norway.
J Chem Ecol. 2008 Nov;34(11):1487-91. doi: 10.1007/s10886-008-9553-9. Epub 2008 Oct 21.
In predator-prey interactions, the prey often have to compromise fitness-related behaviors such as feeding, courting, and territorial defense in order to avoid predators. In these trade-off situations, some behaviors have priority over others. These priorities are not rigid, and may be context-dependent; for instance, many animals show increased risk-taking during courtship behavior by paying less attention to potential predators. We investigated whether the fright reaction, a stereotypical avoidance response to olfactory cues from injured conspecifics, may be affected by reproductive status in a teleost fish, the crucian carp. We demonstrate that among individuals not responding to alarm substances with a fright reaction, the majority were ovulated or spermiated. In females, mean plasma concentrations of 17beta-estradiol and testosterone, gonadal steroids known to decrease during the later stages of sexual maturation, were lower in the individuals not responding with a fright reaction compared to those responding. In males, there were no differences between responsive and non-responsive individuals in mean plasma levels of androgens (testosterone and 11-ketotestosterone) involved in spermatogenesis and male sexual behavior. As the fright reaction in crucian carp consists of behavior incompatible with spawning behavior, we hypothesize that this short-term suppression of the alarm response has evolved so that spawning can occur uninterrupted.
在捕食者与猎物的相互作用中，猎物常常不得不牺牲与适应性相关的行为，如觅食、求偶和领地防御，以躲避捕食者。在这些权衡情况下，某些行为比其他行为更具优先级。这些优先级并非一成不变，可能取决于具体情境；例如，许多动物在求偶行为中会通过减少对潜在捕食者的关注来增加冒险行为。我们研究了惊吓反应（一种对来自受伤同种个体的嗅觉线索的典型回避反应）是否会受到硬骨鱼鲫鱼繁殖状态的影响。我们证明，在对警报物质没有产生惊吓反应的个体中，大多数已经排卵或排精。在雌性中，与有惊吓反应的个体相比，对警报物质没有产生惊吓反应的个体中，已知在性成熟后期会降低的性腺类固醇17β - 雌二醇和睾酮的平均血浆浓度较低。在雄性中，参与精子发生和雄性性行为的雄激素（睾酮和11 - 酮睾酮）的平均血浆水平在有反应和无反应的个体之间没有差异。由于鲫鱼的惊吓反应包括与产卵行为不相容的行为，我们推测这种警报反应的短期抑制是为了使产卵能够不受干扰地进行而进化而来的。
