Recent work has shown how to understand the Page curve of an evaporating
black hole from replica wormholes. However, more detailed information
about the structure of its quantum state is needed to fully understand
the dynamics of black hole evaporation. Here we study entanglement
negativity, an important measure of quantum entanglement in mixed
states, in a couple of toy models of evaporating black holes. We find
four phases dominated by different types of geometries: the
disconnected, cyclically connected, anti-cyclically connected, and
pairwise connected geometries. The last of these geometries are new
replica wormholes that break the replica symmetry spontaneously. We also
analyzed the transitions between these four phases by summing more
generic replica geometries using a Schwinger-Dyson equation. In
particular, we find enhanced corrections to various negativity measures
near the transition between the cyclic and pairwise phase.