Funk was made for bass. To bass players, it seems strange when members of the public don't quite know what you do (this happens depressingly often...). With funk; they know. The late 60s onwards heralded a golden age for bass players with players like Bootsy Collins and Bernard Edwards placing the bass up front.
If you want to play funk bass you need a great groove that's for sure. In terms of note selection, it's crazy how many basslines use the four notes taught in this lesson:
Funk Bass Intervals
Intervals are what we're talking about here and it's the root, fifth, minor seventh and octave: the currency of funk bass.