Advanced simple template and natural armor

[Koja of Khazari]

The advanced simple template states that (among other things) you increase the base creature's natural armor by +2. My question is, for a creature without natural armor, what happens? The way I see it, there are two options:

1. A creature without natural armor has no natural armor bonus to increase, so there is nothing to add the +2 bonus to.

2. A creature without natural armor has a natural armor bonus of +0, so the template increases the creatures natural armor bonus to +2.

In my head, #1 makes more sense in the game world. Just because a creature is bigger and tougher doesn't mean its skin turns into leather or chitin or something. But the barkskin spell states that "a creature without natural armor has an effective natural armor bonus of +0", which would support #2. This would seem to answer the question already, but I'm not sure whether that line from barkskin is meant to pertain only to the spell itself. That is, is the line I quoted from barkskin the rule on natural armor, or an exception to the rule on natural armor?

[Deadmanwalking]

#2 is correct. Everyone has a Natural Armor bonus, humans just have one of +0.

[Koja of Khazari]

Deadmanwalking wrote:

#2 is correct. Everyone has a Natural Armor bonus, humans just have one of +0.

I was kind of leaning that way myself. It does lead to some strange situations with the advanced simple template, but it does make more sense overall from a rules perspective. I just wish this was made clear in the rules somewhere other than at the end of the description paragraph of one of the spells in the core rulebook. I suppose this comes from the fact that the only way players have to improve natural armor is through barkskin (or an amulet of natural armor), so that's the only place in the book where that information would be relevant.