The term that can be used to describe evolution by natural selection is SCIENTIFIC THEORY.
Theory means "the best explanation so far."
Scientific theory is a work in progress. It is a well-substantiated explanation of some aspect of the natural world that is acquired through the scientific method, and repeatedly confirmed through observation and experimentation.
Cardiac Muscle, reason its called Cardiac attack when you have that sort of " Heart Attack "
I think that it would be classified in the prokaryotic domain.
