Studying galaxy evolution through cosmic time via the {\mu}Jy radio
  population: early results from eMERGE
  The $e$MERLIN Galaxy Evolution Survey ($e$MERGE) is an ambitious,
multi-tiered extragalactic radio continuum survey being carried out with
$e$MERLIN and the VLA at 1.4GHz and 6GHz. Exploiting the unique combination of
high sensitivity and high angular resolution provided by radio interferometry,
these observations will provide a powerful, obscuration-independent tool for
tracing intense star-formation and AGN activity in galaxies out to $z\sim5$. In
our first data release (DR1) we present $e$MERGE Tier 1, a 15-arcmin pointing
centred on the GOODS-N field, imaged at 1.4GHz with the VLA and $e$MERLIN at
$\sim 0.28''$ resolution down to an rms sensitivity of $\sim 1.2\,\mu$Jy
beam$^{-1}$. This unique radio survey -- unrivaled at 1.4GHz in its combination
of depth, areal coverage and angular resolution in the pre-SKA era -- allows us
to localise and separate extended star-forming regions, nuclear starbursts and
compact AGN core/jet systems in galaxies over the past two-thirds of cosmic
history, a crucial step in tracing the apparently simultaneous growths of the
stellar populations and central black holes in massive galaxies. In these
proceedings we highlight some early science results from $e$MERGE DR1,
including some examples of the sub-arcsecond morphologies and cold dust
properties of 1.4GHz-selected galaxies. $e$MERGE Tier 1 will eventually reach
sub-$\mu$Jy beam$^{-1}$ sensitivity at $0.28''$ resolution over a 30-arcmin
field, providing crucial benchmarks for deep extragalactic surveys which will
be undertaken with SKA in the next decade.
