  A large number of observed exoplanets are part of multiple planet systems.
Most of these systems are sufficiently close-in to be tidally evolving. In such
systems, there is a competition between the excitation caused by planet-planet
interactions and tidal damping. Using as an example two multiple planet
systems, which host planets in the surface liquid water habitable zone (HZ):
Kepler-62 and Kepler-186, we show the importance and effect of both planetary
and stellar tides on the dynamical evolution of planets and on the climate of
the HZ planets.
