  Neutrino masses and the number of light neutrino species can be tested in a
variety of laboratory experiments and also can be constrained by particle
astrophysics and precision cosmology. A conflict between these various results
could be an indication of new physics in the neutrino sector. In this paper we
explore the possibility for reconciliation of otherwise discrepant results in a
simple model containing a light scalar field which produces Mass Varying
Neutrinos (MaVaNs). We extend previous work on MaVaNs to consider issues of
neutrino clumping, the effects of additional contributions to neutrino mass,
and reconciliation of eV mass sterile neutrinos with cosmology.
