  The goal of this paper is to apply the universal gerbe of \cite{CMi1} and
\cite{CMi2} to give an alternative, simple and more unified view of the
relationship between index theory and gerbes. We discuss determinant bundle
gerbes \cite{CMMi1} and the index gerbe of \cite{L} for the case of families of
Dirac operators on odd dimensional closed manifolds. The method also works for
a family of Dirac operators on odd dimensional manifolds with boundary, for a
pair of Melrose-Piazza's $Cl(1)$-spectral sections for a family of Dirac
operators on even dimensional closed manifolds with vanishing index in
$K$-theory and, in a simple case, for manifolds with corners. The common
feature of these bundle gerbes is that there exists a canonical bundle gerbe
connection whose curving is given by the degree 2 part of the even eta-form (up
to a locally defined exact form) arising from the local family index theorem.
