  We show that the computational model based on local Fermionic modes in place
of qubits does not satisfy local tomography and monogamy of entanglement, and
has mixed states with maximal entanglement of formation. These features
directly follow from the parity conservation corresponding to the parity
superselection rule. We generalize quantum superselection rules to general
probabilistic theories as sets of linear constraints on the convex set of
states. We then provide a link between the cardinality of the superselection
rule and the degree of holism of the resulting theory.
