Physical limits on self-replication processes

Using few very general axioms which should be satisfied by any reasonable theory consistent with the Second Law of Thermodynamics we argue that: a) "no-cloning theorem" is meaningful for a very general theoretical scheme including both quantum and classical models, b) in order to describe self-replication, Wigner's "cloning" process should be replaced by a more general "broadcasting", c) "separation of species" is possible only in a non-homogeneous environment, d) "parent" and "offspring" must be strongly correlated. Motivated by the existing results on broadcasting which show that only classical information can self-replicate perfectly we discuss briefly a classical toy model with "quantum features" - overlapping pure states and "entangled states" for composite systems.