Griffiths David
Zoology Department, University of Dar es Salaam, Tanzania.
Oecologia. 1993 Apr;93(4):531-537. doi: 10.1007/BF00328962.
The number of larvae of the pit-digging ant-lion Macroleon quinquemaculatus at a food-poor site in Tanzania increased between May and October 1983 and then remained at high density until the following rainy season in March. Food availability was low and small larvae were most likely to suffer food shortage. Hunger level varied within and between instars: hunger was greatest after moults and only third-instar larvae weighing more than 100 mg were well fed. A simple model showed that exploitation competition was asymmetric and most likely to affect small larvae, by removing small prey. Exploitation was estimated to reduce food intake by 30-60%. Within-site differences in growth rate and size were associated with differences in larval density. Small larvae were much more likely to move than large larvae; the latter tended to occupy the periphery of the habitat. The reduction in food intake experienced by small larvae was a consequence of interference competition, which was the main factor operating at this site.
1983年5月至10月间，坦桑尼亚一个食物匮乏地点的穴蚁蛉幼虫数量增加，随后一直保持高密度，直至次年3月的雨季。食物供应不足，小幼虫最容易遭受食物短缺。饥饿程度在龄期内和龄期间有所不同：蜕皮后饥饿程度最高，只有体重超过100毫克的三龄幼虫营养充足。一个简单的模型表明，掠夺性竞争是不对称的，最有可能通过捕食小型猎物影响小幼虫。据估计，掠夺行为使食物摄入量减少了30%至60%。生长速率和体型的位点内差异与幼虫密度差异有关。小幼虫比大幼虫更易移动；大幼虫倾向于占据栖息地的边缘。小幼虫食物摄入量的减少是干扰性竞争的结果，干扰性竞争是该地点的主要作用因素。
