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What is the minimum number of working individuals that would be necessary for the survival of a settlement on Mars?
Hillary Shaw
Newport, Shropshire, UK
The 50/500 rule you would need 500 people to prevent genetic drift, although 50 might be sufficient to prevent inbreeding. Genetic drift is an insidious process within small populations that can cause certain variations to be lost. For example, just 2 per cent of the world’s population have green eyes, so this variant could be lost over time in a small population if the few green-eyed people have less offspring. Then we tend…
