Are Ability Scores biological or sociocultural? Both?

I suppose you could also I add Ability Minimums/Maximums as well. This is just some idle chitchat that's been joggin' in my noggin specifically around Intelligence.

Take Half-Orcs for example: +2 Strength, -2 Intelligence, -2 Charisma in D&D 3.5. How much of that -2 Intelligence is a natural lack of mental capacity and how much the lack of education from being a monstrous, ostracized, and probably unwanted child? The same can be asked for Strength (natural Orcish muscles or a life of hard, possibly forced labor?) and Charisma (natural gruffness or underdeveloped social skills?). Then you cases that are unambiguous: A Mind Flayer's Intelligence really does mean it's smarter than you; an 8-foot tall Half-Ogre's Strength really is just plain stronger.

But if ability scores can be sociocultural as well as biological then that opens interesting design space. How about priest-caste human with -1 Str and Con but +2 Wis? What about peasant humans with +1 Str and Con but -2 Int? Or a city-dweller human with +1 Int and Cha but -2 Wis? Do members of a culture that emphasize hard work and self-control get +1 Int and -1 Cha? Do members of a culture that pushes freedom of speech get +1 Cha but -1 Wis?

And going off this idea you can tailor a bunch of different sociocultural backgrounds that can change abilities even further. For example;

Dwarf Caste	Ability Bonus	Ability Penalty
Artisan	+1 Int, +1 Cha	-2 Wis
Miner/Laborer	+1 Con	-1 Cha
Priest	+1 Int, +1 Wis	-2 Str
Warrior	+1 Str, +1 Con	-2 Dex

Using AD&D Dwarves as a base, a dwarf of the miner caste would get +2 Con, -2 Cha (which are 3.5's ability adjustments for dwarves) while a dwarf of the soldier caste would get +1 Str, +2 Con, -2 Dex, and -1 Cha.

What do you think?