Data from: Toxicity and utilization of chemical weapons: does toxicity and venom utilization contribute to the formation of species communities?

Toxicity and the utilization of venom are essential features in the ecology of many animal species and have been hypothesized to be important factors contributing to the assembly of communities through competitive interactions. Ants of the genus Monomorium utilize a variety of venom compositions, which have been reported to give them a competitive advantage. Here, we investigate two pairs of Monomorium species, which differ in the structural compositions of their venom and their co-occurrence patterns with the invasive Argentine ant. We looked at the effects of Monomorium venom toxicity, venom utilization, and aggressive physical interactions on Monomorium and Argentine ant survival rates during arena trials. The venom toxicity of the two species co-occurring with the invasive Argentine ants was found to be significantly higher than the toxicity of the two species which do not. There was no correlation between venom toxicity and Monomorium survival; however, three of the four Monomorium species displayed significant variability in their venom usage which was associated with the number of Argentine ant workers encountered during trials. Average Monomorium mortality varied significantly between species, and in Monomorium smithii and Monomorium antipodum, aggressive interactions with Argentine ants had a significant negative effect on their mortality. Our study demonstrates that different factors and strategies can contribute to the ability of a species to withstand the pressure of a dominant invader at high abundance, and venom chemistry appears to be only one of several strategies utilized.毒液毒性（venom toxicity）与毒液利用（venom utilization）是诸多动物物种生态中的核心特征，学界曾推测其可通过种间竞争作用，在群落组装（community assembly）过程中发挥关键驱动作用。单家蚁属（Monomorium）蚂蚁可产生多种毒液组分，相关研究表明这类毒液能为其带来竞争优势。本研究选取两对单家蚁属物种作为研究对象，它们的毒液组分结构及其与入侵阿根廷蚁（Argentine ant）的共存模式均存在差异。我们通过竞技场试验（arena trials）考察了单家蚁属蚂蚁的毒液毒性、毒液利用策略以及物理攻击行为对单家蚁与阿根廷蚁存活率的影响。研究发现，与入侵阿根廷蚁共存的两个单家蚁属物种，其毒液毒性显著高于未与其共存的另外两个物种。毒液毒性与单家蚁属蚂蚁的存活率之间未呈现显著相关性；不过，在4个单家蚁属物种中，有3个物种的毒液使用模式存在显著差异，且该差异与试验中接触到的阿根廷蚁工蚁数量相关。不同单家蚁属物种的平均死亡率存在显著差异；其中，史密斯单家蚁（Monomorium smithii）与反足单家蚁（Monomorium antipodum）在与阿根廷蚁发生物理攻击互动后，死亡率会显著升高。本研究表明，诸多因素与策略可共同助力物种应对高丰度优势入侵物种的生存压力，而毒液化学组分仅为其中一种可用策略。