Parasite‐Induced Fruit Mimicry in a Tropical Canopy Ant
Parasite‐Induced Fruit Mimicry in a Tropical Canopy Ant
复制标题
热带树冠蚂蚁中寄生虫诱导的水果拟态
作者：
S. Yanoviak;M. Kaspari;R. Dudley;G. Poinar
一些寄生虫修改中间宿主的特征以便于后续宿主消耗它们，但寄生虫介导的模仿的例子很少见。在这里，我们报道了寄生线虫的蚂蚁的外表和行为发生了戏剧性的变化，以至于它们类似于热带雨林树冠上的成熟果实。与完全黑色的健康蚂蚁不同，受感染的蚂蚁有鲜红色、浆果状的胃部，里面充满了寄生虫卵。当蚂蚁行走时，受感染的胃溃疡被保持在明显的高位，它们很容易与活着的蚂蚁分开，后者也表现出防御反应减弱。这种变化的组合可能使受感染的蚂蚁对食果鸟类具有吸引力，食果鸟类摄取红色胃肠并将寄生虫卵传递到粪便中。蚂蚁收集粪便，然后喂给发育中的幼虫，从而完成这个循环。这是第一次关于寄生虫在动物宿主中引起明显的水果拟态以完成它们的生命周期的文献。
Some parasites modify characteristics of intermediate hosts to facilitate their consumption by subsequent hosts, but examples of parasite‐mediated mimicry are rare. Here we report dramatic changes in the appearance and behavior of nematode‐parasitized ants such that they resemble ripe fruits in the tropical rain forest canopy. Unlike healthy ants, which are completely black, infected ants have bright red, berry‐like gasters full of parasite eggs. The infected gasters are held in a conspicuous elevated position as the ants are walking, and they are easily detached from living ants, which also exhibit reduced defensive responses. This combination of changes presumably makes the infected ants attractive to frugivorous birds, which ingest the red gasters and pass the parasite eggs in their feces. The feces are collected by ants and fed to the developing brood, thus completing the cycle. This is the first documentation of parasites causing apparent fruit mimicry in an animal host to complete their life cycle.