''By the way did you know that people who live in snow countries don't sleep?''
''Huh why not?''
''Well if they fall asleep, they will die.''
''That's ridiculous! Everybody has to sleep!''
''It's true. I heard it a long time ago from someone''
''Did Usopp tell you that?''
''Nope. I heard it in a village tavern.''
--- Chapter 134
Luffy possibly heard it from Shanks (long time ago / village tavern). It's also interesting that Blackbeard chose to go Drum island for some reason that we don't know, mostly for plunder perhaps, but it's still interesting.
And now we know Aokiji (the person who has the power of cold) is joining forces with someone from the snow country.
And Blackbeard's natural enemies are ; Fire DF users (Ace, Sabo) / the marines (magma user Akainu is the fleet admiral) / monster trio; (Red hawk, Diable Jambe) Luffy, Sanji, and Zoro once said he wanted a fire sword.
Cold vs. Heat kind of thing, it can't be a coincidence.