If the biological state is "very well defined" then please point us to the definition. Is it based solely on skin hue and reflectance, or are there other factors? Do some people in South Asia with very dark skin meet that definition or are they excluded?

I'm not just trying to be argumentative here. If scientists want to produce high quality, reproducible research then they must precisely define their terms. They can't just assume that everyone has the same understanding and knows what they mean.