Question, is it theoretically possible for a creature, insect or otherwise, to breathe fire or mimic the action? I ask because fire breathing giant ants from fallout and I want to know how to explain that in my fallout PNP game.

thexenobiologist:

bogleech:

I don’t know my chemistry but there have to be some compounds an organism could manufacture and mix together that ignite on contact with the air.

There’s already bombardier beetles whose chemical spray reaches boiling temperatures in a split second.

The issue with fire-breathing isn’t so much actually doing it, but rather evolving the ability to do so. Transitional forms are always something that need to be considered; there are plenty of things that, despite being biologically possible, could never really evolve naturally. When it comes to fire breathing, there are three things you need to evolve simultaneously: a fuel, an ignition system, and protection. If you’re missing one of those, then the other two are either useless or actively harmful.
In the case of bombardier beetles, the chemicals they use are derived from those used by other beetles to produce a smelly goop; some even use a less extreme reaction to help spray it out! But with fire, this sort of gradual change isn’t really an option; you either have ignition or you don’t.

Of course, all this only applies to naturally-evolved organisms. Genetically modified ones don’t have those sort of restrictions, since they didn’t evolve over time. If you want fire-breathing ants, then you could either a) have them be genetically modified, or b) have their “fire” be caustic chemicals rather than actual flame (plenty of real ants use these sorts of chemicals already).