The changing frequencies of alleles over periods of time. That is what’s considered “controversial” here in the U.S. This is the very definition which inflicts fear, hate, and ignorance in religious circles – so much so they completely deny its very existence as a natural law of biology. I am, of course, talking about evolution.
For some, they accept micro-evolution, but not macro-evolution. They say they can’t imagine how an ape-like ancestor could evolve into us over millions of years, but a slight change among species in a course of a few years is acceptable. Hmmm….so if a species of animal can develop subspecies, with a clear difference in phenotype, in only a few years, I wonder what that species of animal would look like in a million years!? Oh, that’s right, they’ll look absolutely nothing alike! The only means of determining their relation will be through their DNA and bone structure!
News flash, creationists: you can’t have micro-evolution without macro-evolution, just as you can’t have macro-evolution without micro-evolution. You can’t have one without the other! Either you accept the science of evolution or you remain hidden in the shadows of ignorance passed onto you.
P.S. Evolution isn’t just a theory…as if you actually knew what that meant.