I play a lot of reggae bass. Bob Marley is a great place to start if you want to learn the art of reggae bass. "Family Man" Barrett is a world class bass player.
The most important part of reggae bass is timing. No question. It isn't just the notes you play, but the space and time left between notes. I've heard passionate bass line that consisted of only a few notes per measure, but their timing was precise and impactful.
If you listen carefully to reggae you will notice that many times the bassist will not play a note on the first beat of each measure. This is what has come to be known as the "one drop".
A good example is the song "War" by Marley. This is tricky at first, and it takes some discipline to lay off that root note where it's normally played. To make things even trickier, the guitar is almost always playing on the upbeat. It's best to not think too hard, just try and let it flow.
Other than that, that other post is pretty accurate. Outline the chords a lot, and use a lot of minors.
DS5
