Originally Posted by xepherys

Interesting. First of all, most of my observations are not based on internet readings, but classes and book knowledge I've collected over the years. While I'm the first to admit I am not a geneticist, I do have a fundamental knowledge, on a larger scale, of how the human body operates and how evolution takes it's grip over time.

Yes, darker skin is better regarding exposure to sunlight, and most current data shows that humans BEGAN their existance as darker skinned people in northern Africa and the Mesopotamian areas. Lighter skin developed primarily in people who migrated north and began having seasons that kept them out of the sun year-round. This, already, signifies that our sun exposure is taken into consideration in our genetic makeup.

Your primary points regarding the dimers are absolutely correct. That does not, however, mean that our genetic makeup has not greatly improved our sunshine survivability over the course of thousands of years. As a scientist, I'm sure you understand that there is a difference between corresponding and causal factors when making such a statement. The same could be said for many things that are part of our daily lives. Please do not use a large vocabulary and a shield of science to bring about a facade of perfected knowledge. Since there are legitimate scientists on both ends of the spectrum regarding sunscreen and sun exposure, one would logically conclude that nobody knows with 100% certainty what the compound effect is. There are pros and cons, good and bad to just about everything in life. It's the overall compound nature of those effects, all added up (hence compound), that determine our views and knowledge.