  Cosmological gamma-ray bursts (GRBs) and their afterglows seem to result from
dissipation of bulk energy in relativistic outflows, but their engine has not
been unambiguously identified. The engine could be a young pulsar formed from
accretion induced collapse with a dynamo amplified field. Elsewhere, we suggest
that such a ``Usov type'' strong field pulsar may help explain the bimodal
distribution in GRB durations. Here we discuss possible roles of a pulsar for
the afterglow. We derive the expected bolometric luminosity decay. The
extracted rotational energy could dissipate by shocks or by large amplitude
electromagnetic waves (LAEMW). The simplest LAEMW approach predicts a slower
decay in observed afterglow peak frequency and faster decay in flux than the
simplest blast-wave model, though more complicated models of both can provide
different dependences. LAEMW do not require the rapid magnetic field
amplification demanded of the blast-wave approach because the emission
originates from a nearly fixed radius. Different time dependent behavior of GRB
and post-GRB emission is also predicted. Observational evidence for a pulsar in
a GRB would make some GRB engine models, such as neutron star mergers and black
holes unlikely. Therefore, the question of whether a pulsar is present is an
important one even if it could drive a canonical fireball.
