I could be wrong here, but it seems to me that a common aspect amongst all languages is the tendency to raise the pitch of your voice slightly when asking a question. Especially at the end of a question sentence.
If I’m wrong about this raised pitch being common amongst all languages, at the very least do all languages change their tone slightly to indicate that a question is being asked?
I guess there needs to be some way to indicate what is and isn’t a question. Perhaps a higher pitched voice reflects uncertainty. Is this something deep rooted in humans, or just an arbitrary choice when language developed?
The general pattern seems cross-linguistically consistent.
It’s not even consistent in English.
Yeah - I noticed it after reading your other comment. Fair point.
Coupling it with info from the Mandarin article that I’ve linked, it seems to apply to declarative (yes-no) questions only.