首都废土的火蚁來自一个名为莱斯科博士的倒霉科学家在意外中创造了这种生物。他的本意是通过一系列的基因操作，将巨蚁的体型转化至变异前的水平。在他的设想中，这种基因上的改变将使巨蚁产下的后代体型缩小一些，这样一代一代下来，巨蚁终究会回归到以前的体型。不幸的是，基因转变这种高难度的实验在操作上与理论产生了一点小小的偏差，而基因上一点点的不同足以使整个物种产生难以预料的变异。更糟糕的是，莱斯科博士在意识到这个偏差之前，感觉原先设想中一代一代缩小体型实在是太费事了，于是想用大名鼎鼎的FEV强制进化病毒来加快这个进程，那一点点的偏差又被放大，结果就导致巨蚁拥有了喷火的能力。根据莱斯科博士的研究，火蚁的体内有能够产生和储存可燃气体的器官，将这些气体喷出的同时通过下颚的摩擦点火，He calls this process "pyrosis."<section begin="Background" />
It is not known how fire ants came to be in the Mojave Wasteland, but theories are that their ability to breathe fire has been developed in the same way as the similar ability of fire geckos.<section end="Background" />
Fire ant nest guardian编辑
Fire ant nest guardians are much harder to kill than any other type of fire ant. There are five of this kind of ant protecting the queen. Doctor Lesko refers to these ants as "The Queen's Quintet."
Fire ant soldiers are the second lowest ranked ant in the fire ant colony. Their job is to protect their area from intruders. They are very aggressive and will attack humans, as well as other creatures on sight.
Fire ant warrior编辑
Warrior fire ants are the predominant variety of ant you will encounter in the Marigold Metro tunnels in the Capital Wasteland.
Fire ant workers are the backbone for the ant community's infrastructure. As the name implies, they dig tunnels and care for the eggs. However, they will attack intruders if they are threatened.
Despite the fact that the rest of the colony has gained the ability to spit fire, the queen lacks this trait, it uses a ranged acid spitting attack instead.
- Since they breathe fire, they will ignite gas leaks that may be present in the area.