Are these two musical skills separate disciplines or are they regarded as interchangeable? By percussion, I mean instruments like congas and cowbells rather than marimbas, vibes and so on. Whilst I imagine they are taught as distinct subjects in music schools, in the real world I'd venture the distinction can be blurred somewhat. Ray Cooper is a good example; he is often seen with a set of congas, tambourine and gong but I've also seen him play a full drum kit.
Thankyou.