[quote=@Frettzo]
Nobody really taught humanity how to build castles either. We explained it a while ago by Humanity evolving on its own.
[/quote]

This would make sense if humanity had existed with agriculture for more than the 20-30 years that they have, but as is I doubt they realistically would have invented anything on their own. There has hardly been any time and the population is small and spread apart.

I suppose I'll chalk it up to knowledge spreading from Zerabil.