On the contrary, the theory of evolution is irrelevant to serious scientific study. Variations within species do NOT prove this nutty theory. The theory of evolution is dependent on the belief that entirely new species are created by natural selectivity over time. That just can't happen, scientifically. Hence, the laughably expansive leap of faith as so-called scientists put their eggs in the evolution basket.
The species is an artificial category created by humans. Putting any significance on it as a limit on evolution betrays a fundamental misunderstanding of descriptive biology.
Q. for creationists: are Bullock's Orioles and Baltimore Orioles the same species?