The Hutterites, apparently. This from Eli Berman’s “Radical, Religious and Violent” and by the way the Hutterites qualify for only two of the three:
Over the next seventy years [starting 1877] the Hutterites set the world record for natural population increase, growing from 443 members to 8,542, a 4.1 per cent annual rate of increase! That remarkable population growth rate implies twice as many members every 17 years. In their honor, demographers have dubbed their population growth rate the Hutterite standard– the effective maximum growth rate of a population benefiting from modern standards of nutrition and healthcare. Hutterites were socially isolated enough from the rest of the American population that most of their population increase was due to high fertility, not to recruitment of oustiders to the fold.
You learn something every day.
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