This idea isn't new, but I wonder what would happen if you created a country in a high-altitude area that implemented the following rules:
- The only people allowed inside will be those who've run a sub 17 5K (for men) or a sub 20 5K (for women). This is fast enough to weed out those with no talent, but slow enough to have some genetic diversity.
- People from that country can only breed with other people from that country. The faster their PRs are, the more kids they'll be allowed and encouraged to have.
- Any guy who can't run a sub 17 5K or girl who can't run a sub 20 5K by his/her 18th birthday will be kicked out.
- Over a few decades, the standards will be raised from a sub 17 5K to a sub 15 5K.
Without considering other factors such as wars, illegal immigration, and the need to develop a functioning economy, what would happen after a few generations? Would the country die out, or would you get a "super race" of guys who can run a sub 12?