Suppose someone has asked "How could I do this thing in my fiction world?" or "If such a thing happened in my fiction world, what would be the consequences?" As such, the question is completely on-topic for this site.
However, it has happened here rather often that the answer to the question turns out to be, "It exists, right here, right now, in this non-fiction world. Here's a link to the Wikipedia article about it."
Suddenly, in a bit of an ex post faco sense, the question is no longer about World Building per se, but rather physics, astronomy, biology, history, or some other perfectly good neighboring SE site.
Here are six examples I found with just a cursory glance around a few minutes ago (granted I have participated in five of these either as answerer or commenter).
- what kind of poison a octopus can carry to kill a person via skin contact with poison?
- How can zombies be explained without using magic?
- Can asteroid fields exist in local systems?
- Would it be possible to skip an asteroid off of a planet's atmosphere?
- What happens to an empty, modern city?
- What earth conditions would make a permanent bronze-colored sky?
My thinking is let it be, as it does add to this site. The OP probably had no idea such a thing could be, and learned from it. I mean, how often does the zombie ant fungus come up in every day conversation? But you know about it now!
I am curious what others have to say.