I'm not really proposing a standard. I'm just wondering if we've ever actually caught evolution in the act in humans. If we haven't, that doesn't mean it's wrong. You know, the old "lack of evidence" vs. "evidence of lack" thing.
Whether we've seen evolution in humans is a different matter from detecting a new mutation. Evolution is the variation over time of allele frequencies in a population of organisms. I don't know whether any real studies of allele frequencies in humans have ever been done or not, but now that we can sequence genomes, it should be easier to detect a shift in allele frequencies. Previous to the ability to do genetic sequencing, only phenotypes, not genotypes would have been determinable, so I'm not sure if it would be possible to conclusively observe evolution in a human population, although I would guess that a study of the relative frequency of certain phenotypes would enable scientist to say something about genotype frequencies.
Skin color is evidence of evolution. It filters the sunlight to affect vitamin D concentrations, especially important in pregnant women for infant mortality.
Going from highest sunlight environment to lowest, Africa to Scandanavia you go from darkest skin to lightest in a gradient.
Allele frequency change in populations over time=EVOLUTION.