how people found out the cooking time of food that need large cooking times

Question

There´s reocurring joke that 6 guys died trying to find when to eat a venomous fish that needs 7 days to cook, In Brazil ppl eat mandioca leaves, also 7 days, how the hell folk back then decided they needed to eat that and how they came to the number of DAYS needed to cook that thing clearly unfit for human consumption?

In: 5

Answer 1

ELICaveMan:

Ugg put meat on fire. Ugg wait short bit. Ugg eat meat. Ugg die!

Ugg brother Ogg put more meat on fire. Ogg wait longer bit. Ogg eat meat. Ogg finds meat tasty! Ogg lives!

Now all Ogg Tribe wait longer bit before eat meat!