  In the context of thermodynamics we discuss the way inevitable emerge an
interaction between dark components, and in this way, provide a mechanism to
understand the limits of the LCDM model and the class of interaction models
between dark components. Using observational data we have tested two models of
explicit interaction between dark components and reconstructed the evolution of
temperatures for both components. We found that observations suggest the
interaction exist with energy flowing from dark energy to dark matter. The best
fit also suggest a phantom equation of state parameter for dark energy. We
discuss the results having in mind the constraints imposed by thermodynamics.
