Chemical warfare among invaders: a detoxification interaction facilitates an ant invasion

As tawny crazy ants (Nylanderia fulva) invade the southern USA, they often displace imported fire ants (Solenopsis invicta). Following exposure to S. invicta venom, N. fulva applies abdominal exocrine gland secretions to its cuticle. Bioassays reveal that these secretions detoxify S. invicta venom. Further, formic acid, from N. fulva venom, is the detoxifying agent. N. fulva exhibits this detoxification behavior after conflict with a variety of ant species; however, it expresses it most intensely after interactions with S. invicta. This behavior may have evolved in their shared South American native range. The unique capacity to detoxify a major competitor’s venom likely contributes substantially to its ability to displace S. invicta populations, making this behavior a causative agent in the ecological transformation of regional arthropod assemblages.随着黄疯蚁（Nylanderia fulva）入侵美国南部区域，它们通常会取代入侵红火蚁（Solenopsis invicta）的种群。当黄疯蚁接触到入侵红火蚁的毒液后，会将自身腹部外分泌腺的分泌物涂抹于体表角质层。生物测定实验证实，这类分泌物可对入侵红火蚁的毒液发挥解毒作用。进一步研究发现，黄疯蚁自身毒液中的甲酸正是该解毒活性成分。黄疯蚁在与多种蚁类物种发生冲突后，均会表现出此类解毒行为，但在与入侵红火蚁交互后，该行为的表达强度最高。这类解毒行为或许起源于二者共享的南美原生分布范围。黄疯蚁具备解毒主要竞争者毒液的独特能力，这极大概率极大地推动了其取代入侵红火蚁种群的进程，使得该行为成为驱动区域节肢动物群落生态重塑的关键成因。