ttc,
Regina Jacobs
Cathal Lombard
Ayhan
Jerome Young
Tim Montgomery
Mickey Grimes
All convicted dopers who got beat by someone else. It's not magic.
You have a population who, for thousands of years (since the dawn of man), have lived at altitude. This (it is postulated) accounts for their unique adaptation to low O2 environments -- different than in those adaptations observed anywhere else on the planet.
They have also relied on their own two feet for running to and fro as well as farming and grazing. Thus, those who were naturally adept to running around better, were more likely to be successful, etc.
So this population with a unique adaptation to low O2 environments and thousands of years of selection for those better at running, and many of them run long distances every day from early on in youth in addition to chasing goats after school and going long distances to fetch water.
Then you take one of them, who has been running 20km daily, in addition to all the farming, and when he grows up you put him on a good program, with consistent training and steady mileage.
You get the most talented runners in the world on the best program possible, all training under the same system, with set goals: world/olympic titles and WRs. Money comes second, glory for Ethiopia first. That's why they are so much better.