Now, let's listen to the following track.
Bass: Joe Ayoub.
There are not a lot of other instruments playing; therefore, it's, kind of easy, to start talking/learning about the Bass player's job/role in the band.
A bass player - like a COMPOSER - creates a TEMPLATE of the bass-line for this/that track and its sections(!).
There are a lot of requirements (even for a simple pop song) what the bass line must accomplish for this/that song/track.
When a bass player writes a TEMPLATE, that TEMPLATE must have all the MELODY requirements - dynamics, articulation, note length, etc...
And that template must be DEVELOPED - like any COMPOSERS do, etc...
It's such a LONG TOPIC, with so many NUANCES - it's a VERY LONG STUDY!
My biggest pet peeve about some bass players.
First measures - the bass line is "Breathing," but (let's say, in Verse 2 and further) the bass player is already BORED, the drum player or rhythm guitar player starts "exercising."
In short, every MEASURE requires the bass player to MAKE/to weave that "carpet."