Was everyone just sick all the time? How did they keep everyone from dying?
In: 12
Observation and evolution. The ones that observed unsanitary conditions made you sick and avoided those conditions survived and passed on their knowledge. The ones that didn’t notice died.
Doesn’t just apply to humans, lots of animals will have designated zones for their waste. That’s the evolution part, they probably don’t know why they are doing it, just that the ones that do survive.
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