  Three-dimensional gauge theories coupled to fermions can develop interesting
nonperturbative dynamics. Here we study in detail the dynamics of $SU(N)$ gauge
theories coupled to a Dirac fermion in the rank-two symmetric and antisymmetric
representation. We argue that when the Chern-Simons level is sufficiently small
the theory develops a quantum phase with an emergent topological field theory.
When the Chern-Simons level vanishes, we further argue that a baryon condenses
and hence baryon symmetry is spontaneously broken. The infrared theory then
consists of a Nambu-Goldstone boson coupled to a topological field theory. Our
proposals also lead to new fermion-fermion dualities involving fermions in
two-index representations. We make contact between our proposals and some
recently discussed aspects of four-dimensional gauge theories. This leads us to
a proposal for the domain wall theories of non-supersymmetric gauge theories
with fermions in two-index representations. Finally, we discuss some aspects of
the time-reversal anomaly in theories with a one-form symmetry.
