At some point, they were not phonemically distinct and then became so -- and I am not sure when, or even if it's known exactly when. What I do know is that the breath marks did not exist when the poems were written nor when the oldest manuscripts of this collection were written, meaning that they have been added by modern editors. I am familiar enough with the classical language that I can supply many of them myself, when confronted with the original spelling, but I still prefer the edited version.

---L.