Department of Psychology, Neuroscience and Behaviour, McMaster University , Hamilton, Ontario , Canada L8S 4L8.
Biol Lett. 2019 Jun 28;15(6):20190266. doi: 10.1098/rsbl.2019.0266. Epub 2019 Jun 5.
Generalist populations are often composed of individuals each specialized on only a subset of the resources exploited by the entire population. However, the traits underlying such niche variation remain underexplored. Classically, ecologists have focused on understanding why populations vary in their degree of intraspecific niche variation, with less attention paid to how individual-level traits lead to intraspecific differences in niches. We investigated how differences in behaviour, morphology and microhabitat affect niche variation between and within individuals in two species of spider Anelosimus studiosus and Theridion murarium. Our results convey that behaviour (i.e. individual aggressiveness) was a key driver of intraspecific trophic variation in both species. More aggressive individuals capture more prey, but particularly more Coleoptera, Hymenoptera and Diptera. These findings suggest that behavioural traits play a critical role in determining individuals' diet and that behaviour can be a powerful force in driving intraspecific niche variation.
一般来说，种群通常由专门针对整个种群所利用的资源子集的个体组成。然而，支持这种生态位变异的特征仍然没有得到充分的探索。传统上，生态学家一直致力于理解为什么种群在种内生态位变异程度上存在差异，而较少关注个体水平的特征如何导致种内生态位的差异。我们研究了行为、形态和微生境的差异如何影响两种蜘蛛 Anelosimus studiosus 和 Theridion murarium 个体间和个体内的生态位变异。我们的结果表明，行为（即个体攻击性）是这两个物种种内营养变异的关键驱动因素。更具攻击性的个体捕获更多的猎物，但特别多的鞘翅目、膜翅目和双翅目。这些发现表明，行为特征在决定个体饮食方面起着关键作用，并且行为可能是推动种内生态位变异的强大力量。
