Fair enough. Exponential growth can be pretty amazing. But think of it this way. Let's say the total population of Europe was 20,000,000 at some point in the m

Fair enough. Exponential growth can be pretty amazing. But think of it this way. Let's say the total population of Europe was 20,000,000 at some point in the middle ages in the countries from where the Ashkenazi Jews originated (corresponding to the time that there were 330 Jews). [1] This is a very crude estimate, as the population certainly varied a lot. So you're telling me that those 330 Jews out-competed 20,000,000 gentiles to such an extent that, before the Nazis and WWII, there were (perhaps) 10,000,000 Jews in Europe? That growth seems very high. My guess would be 20,000,000 people overall in the middle ages means at least 20,000 Jews (0.1% of total). But if there really were only 330 (really only 165 couples?) then they certainly had a knack of "getting it done"! This implies that Jews were much more adept than the general population at "survival", reproducing in each generation regardless of all the droughts, wars and plagues. One other explanation would be that the 330 starting number is accurate but corresponds to an earlier period of time, maybe 2,000 years ago, not 600 to 800 years ago as the article claims. [1] http://en.wikipedia.org/wiki/Medieval_demography http://en.wikipedia.org/wiki/Medieval_demography