  We generalize the mean field magnetic dynamo to include local evolution of
the mean vorticity in addition to the mean magnetic field. The coupled
equations exhibit a general mean field dynamo instability that enables the
transfer of turbulent energy to the magnetic field and vorticity on larger
scales. The growth of the vorticity and magnetic field both require helical
turbulence which can be supplied by an underlying global rotation. The dynamo
coefficients are derived including the backreaction from the mean magnetic
field to lowest order. We find that a mean vorticity field can actually seed
exponential growth of mean magnetic field from only a small scale seed magnetic
field, without the need for a seed mean magnetic field. The equations decouple
when the fluctuating velocity and magnetic field cross-correlations vanish,
resulting in the separate mean field magnetic and mean field vorticity dynamo
equations.
