This question is relevant to the one enter link description here
As one answered in that question, different fermions species also follow anti-commutation.
But why in transverse Ising field, spins on differents sites commute while on the same site anti-commute? At first I thought it's because distinguishability.
But the answer in that question clearly hints distinguishability is not the reason for anti-commutation, because different fermion species are obviously distinguishable.
So could any one help to explain why in transverse Ising field, spins on differents sites commute while on the same site anti-commute?