Cannibalism‐mediated life history plasticity to combined time and food stress
Cannibalism‐mediated life history plasticity to combined time and food stress
复制标题
同类相食介导的生活史可塑性对时间和食物压力的影响
DOI：
10.1111/j.0030-1299.2004.12974.x
复制
发表时间：
2004
期刊：
影响因子：
--
通讯作者：
R. Stoks
中科院分区：
文献类型：
--
作者：
M. Block;R. Stoks
人们越来越意识到，生物压力和时间压力的组合在塑造生活史可塑性方面相互作用。尽管食人现象广泛而丰富，但在将这两种类型的限制与生活史可塑性联系起来的过程中，食人现象的作用在很大程度上被忽视了。此外，没有研究区分食人族的直接(由于额外进食)和间接(由于竞争对手被淘汰)的生活史影响，也很少知道它们对这些限制的不同依赖。我们研究了在时间胁迫(通过控制生长季节可获得的感知时间)和食物胁迫的组合下，同类相食对绿色豆蛾生活史的影响。我们每两个杯子饲养一只幼虫，通过防止一半的杯子吃人和控制吃人后的人均食物增加，消除了吃人的直接和间接影响。在时间压力和食物压力下，食人行为更加频繁，我们的结果表明，这可能有助于食人者弥补这些限制对生活史施加的负面影响。吃人的直接和间接好处(发育和生长速度加快，出现时质量较大)都取决于吃人的时机，吃人的时间更明显，或者只有在吃人的早期才会出现。此外，我们还发现，生态约束(时间压力和食物压力)也不同地影响了一些直接和间接的影响。鉴于直接和间接影响的不同背景依赖性，以及直接和间接生活史影响可能在塑造生活史方面都很重要的事实，理清这些影响对于机械地理解在哪些条件下吃人预计是适应的或不适应的至关重要。
There is increasing awareness that combinations of biotic and time stress interact in shaping life history plasticity. Despite being widespread and abundant, the role of cannibalism in linking both types of constraints to life history plasticity has been largely neglected. Moreover, no studies disentangled direct (due to the extra meal) and indirect (due to the elimination of the competitor) life history effects of cannibalism, and little is known about their differential dependency on these constraints. We studied effects of cannibalism on the life history of the damselfly Lestes viridis under combinations of time stress (by manipulating the perceived time available in the growth season) and food stress. We reared larvae per two and disentangled direct and indirect effects of cannibalism by preventing cannibalism in half of the cups and by manipulating the per capita food increase after cannibalism. Cannibalism was more frequent under both time stress and food stress and our results show it may help cannibals to compensate for the negative effects of these constraints imposed on life history. Both direct and indirect benefits of cannibalism (increased development and growth rates, larger mass at emergence) were dependent on the timing of cannibalism, being more pronounced or only present when cannibalism occurred early. Moreover, we found that the ecological constraints (time stress and food stress) also differentially shaped some of the direct and indirect effects. Given the differential context-dependency of direct and indirect effects and the fact that direct and indirect life history effects may be both important in shaping life history, disentangling these effects is critical to mechanistically understand under which conditions cannibalism is expected to be adaptive or not.