Levi Bryant has some more reflections on the ontology of culture and ecology.
I find Peter Sloterdijk interesting on these questions. He generally cites Heiner Mühlmann's The Nature of Cultures when he wants to talk about cultures as entities. Sloterdijk's mixing of this kind of socio-biology and grand, sweeping Spenglerian history makes me a little uneasy but it is interesting. Understanding cultures as tensegretic structures (i.e. as holding together in relations of tension) makes a lot of sense.
Although, of course, the temptation is to understand culture as cultivation, as care, as enriching and enlivening. In this sense culture could be understood as a kind of surplus that arrives when beings achieve more complex modes of existence than simple Darwinian selection (Elizabeth Grosz makes more or less this argument). A kind of froth of irreducibility that rises up from natural selection without ever leaving it (but that's the limitation of this metaphor: it suggests epiphenomenality).
Culture is 'what makes life worth living' for beings self-sensitive enough to need a 'life worth living.' (Here 'culture' is very close to Sloterdijk's 'sphere.') It is not what transcends life but what mediates the deadly contradiction of consciousness—at first, anyway; and then it has 'a life of its own.'
It is not a spiritual supplement but, on the contrary, a profoundly down-to-earth necessity. A history of its invention, or rather of its innovations, would require the consideration of far more than cave paintings and string quartets. It would be a nonsensical overreach to say that 'the heart cultivates the blood' or somesuch but do the evolving aesthetics of sexuality cultivate the becoming-reproduced of the sexualised organism? That isn't nonsensical to say.
And so 'nature,' whatever that may be, should have no quarrel with culture; nor should this pair be in need of any 'mediation' of the dialectical sort. If culture is what itself mediates the emergent problems of highly self-sensitive vitality then culture certainly cannot be confused with bio-nature but nor should it be seen as something laid on top of it, an embellishment. Stones and stars might have no need of it but it is easily understood as woven into the biological fabric of living beings of all sorts.
