Humans are very clever. Sometimes I feel very clever because I have learned so many cool facts and skills with the internet, and then I think about all the knowledge I hold that people of the past managed to figure out from scratch, and it blows my mind
If you think about it then boiling is not that easy.
There is almost no way to boil something until you discover pottery and ceramic, and this is quite advanced tech for many early civilizations.
The Haida on the west coast of Canada put red hot rocks in their canoes to render fish. You underestimate humans ingenuity.
Humans are very clever. Sometimes I feel very clever because I have learned so many cool facts and skills with the internet, and then I think about all the knowledge I hold that people of the past managed to figure out from scratch, and it blows my mind