Downstep in the vast majority of cases can be traced to the influence of a low tone [Hyman 1979].This paper discusses the case of Supyire, a three tone language with downstep unrelated to low tone.Sequences of high tones are automatically bunny spa headband downstepped.Confusion with mid tone is in most cases avoided by a rule which raises mid to high tone; the two rules together creating a "flip-flop" effect.
Supyire also has automatic downdrift of mid and high tones following a low tone.It thus presents an flexcon reverse osmosis water storage tank unusual combination of downstep and downdrift in the same language, but unrelated to each other.