Doblas-Miranda Enrique, Reyes-López Joaquín
Departamento de Biología Animal, Facultad de Ciencias, Universidad de Granada, 18071 Granada, Spain.
Environ Entomol. 2008 Aug;37(4):857-61. doi: 10.1603/0046-225x(2008)37[857:fsqrtt]2.0.co;2.
Animals principally forage to try to maximize energy intake per unit of feeding time, developing different foraging strategies. Temperature effects on foraging have been observed in diverse ant species; these effects are limited to the duration of foraging or the number of foragers involved. The harvester ant Messor barbarus L. 1767 has a specialized foraging strategy that consists in the formation of worker trails. Because of the high permeability of their body integument, we presume that the length, shape, and type of foraging trails of M. barbarus must be affected by temperature conditions. From mid-June to mid-August 1999, we tested the effect on these trail characteristics in a Mediterranean forest. We found that thermal stress force ants to use a foraging pattern based on the variation of the workers trail structure. Ants exploit earlier well-known sources using long physical trails, but as temperatures increases throughout the morning, foragers reduce the length of the foraging column gradually, looking for alternative food sources in nonphysical trails. This study shows that animal forage can be highly adaptable and versatile in environments with high daily variations.
动物主要通过觅食来尽量提高单位觅食时间内的能量摄入，从而形成不同的觅食策略。在多种蚂蚁物种中都观察到了温度对觅食的影响；这些影响仅限于觅食的持续时间或参与觅食的蚂蚁数量。收获蚁Messor barbarus L. 1767具有一种特殊的觅食策略，即形成工蚁路径。由于其体表的高渗透性，我们推测野蛮收获蚁觅食路径的长度、形状和类型必定会受到温度条件的影响。1999年6月中旬至8月中旬，我们在地中海森林中测试了温度对这些路径特征的影响。我们发现热应激迫使蚂蚁采用基于工蚁路径结构变化的觅食模式。蚂蚁利用较长的实体路径开发早期已知的食物源，但随着上午温度升高，觅食者会逐渐缩短觅食队伍的长度，转而在非实体路径中寻找替代食物源。这项研究表明，在每日变化较大的环境中，动物觅食具有高度的适应性和灵活性。
