Is "troll node" a thing?

[Hasta]

In a relatively small area underneath my base (~10x10 map grids) in the last 4-6 weeks I've managed to dig up:
- one lvl2 troll (bald)
- two lvl4 trolls (hairy and big-ears)
- two lvl6 trolls (bald and tail)
I don't have a cave hermit credo yet (didn't even had the Miner when I dug up first three).

So, the questions are:
- do trolls spawn in clusters, regionally, not unlike gem nodes or ore types?
- does the fact that my mines are littered with silver (can't make a straight 10-tiles tonnel withoug stumbling upon another tile of galena, literally) affect troll spawn chances in any way?
- is it me? does my character smell weird? why do you hate me jorb?

[Uriel]

Wiki says thats there constant change of diging out trolls for every tile mined.

Ps. Silver is everywhere, I think JLO gave it to much % of ore in mapgen

[Ardennesss]

Yes, it's been relatively proven that there are "nodes" underground, including gemstones and trolls.