  We discuss the relation between fermion entanglement and bipartite
entanglement. We first show that an exact correspondence between them arises
when the states are constrained to have a definite local number parity.
Moreover, for arbitrary states in a four dimensional single-particle Hilbert
space, the fermion entanglement is shown to measure the entanglement between
two distinguishable qubits defined by a suitable partition of this space. Such
entanglement can be used as a resource for tasks like quantum teleportation. On
the other hand, this fermionic entanglement provides a lower bound to the
entanglement of an arbitrary bipartition although in this case the local states
involved will generally have different number parities. Finally the fermionic
implementation of the teleportation and superdense coding protocols based on
qubits with odd and even number parity is discussed, together with the role of
the previous types of entanglement.
