  In the Gray-Scott reaction-diffusion system one reactant is constantly fed in
the system, another reactant is reproduced by consuming the supplied reactant
and also converted to an inert product. The rate of feeding one reactant in the
system and the rate of removing another reactant from the system determine
configurations of concentration profiles: stripes, spots, waves. We calculate
the generative complexity --- a morphological complexity of concentration
profiles grown from a point-wise perturbation of the medium --- of the
Gray-Scott system for a range of the feeding and removal rates. The
morphological complexity is evaluated using Shannon entropy, Simpson diversity,
approximation of Lempel-Ziv complexity, and expressivity (Shannon entropy
divided by space-filling). We analyse behaviour of the systems with highest
values of the generative morphological complexity and show that the Gray-Scott
systems expressing highest levels of the complexity are composed of the
wave-fragments (similar to wave-fragments in sub-excitable media) and
travelling localisations (similar to quasi-dissipative solitons and gliders in
Conway's Game of Life).
