We evaluated the effects of two morphs of the rotifer Keratella tropica (long-posterior spines, LS; short-posterior spines, SS) on life-table parameters and population dynamics of the rotiferan predator Asplanchna brightwelli. At the prey densities of 10 and 30 ind./mL, A. brightwelli showed significantly higher intrinsic rate of population increase, net reproductive rate and population growth rate when fed with SS than when fed with LS. At the prey densities of 10, 20 and 30 ind./mL, A. brightwelli showed higher population growth rate when fed with SS than those fed with LS. Overall, these results indicated that development of long spines could effectively defend against the predation of A. brightwelli on K. tropica.

中文翻译：

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两个影响龟甲tropica变种的捕食者的种群动态晶囊brightwelli

我们评估了轮虫两个变种的影响龟甲tropica ;在生命表参数和rotiferan捕食者的种群动态（长刺后，LS短刺后，SS）晶囊brightwelli。在10和30 ind./mL的猎物密度下，与SS喂养相比，A。Brightwelli的SS种群内在种群增长率，净繁殖率和种群增长率显着更高。在10、20和30 ind./mL的猎物密度下，饲喂SS的A. Brightwelli种群增长率高于饲喂LS的种群。总的来说，这些结果表明，长刺的发展能有效抵御捕食A. brightwelli上tropica。