Yes! You finally got it! The key word here is "generation."<quoted text>
Each generation goes through a survival filter. Encountering new organisms, diseases, chemical and other environmental conditions will require an innate ability to deal with them on an individual basis. Some will, some won't.
Woohoo, hero cookie for you!
Yes, Dave, you're dead on.In the last less than 100 years human civilization has created a totally new environment if you believe we have been linear in development. Chemical, nuclear radiation, EM signatures, and new organisms we have to deal with that have arisen in a very short period of time. Very radical changes. They will not fade away.
How will your gene pool of the past deal with those? They are all over the planet. What will those that survive pass on down the line?
Here's a test of your evo knowledge: where is the greatest selection pressure in humans in this contemporary world you have described?