If you haven't read Standing In The Shadows of Mototown, definitely worth reading - lots of great Jamerson information. While I agree with those who hold that you can't name just one, Jamerson delivered groove and funk at a level that others only caught up with 10 to 20 years later - and he did most of it under tremendous time pressure, making many of the lines up on the spot in the studio, rarely straight, and playing a beat up Precision with the action set high like an upright bass, never cleaning the strings or fretboard, and picking with only his right index finger. The latest versions of Standing in the Shadows come with two CDs of modern bassists interpreting Jamerson's bass lines - everyone from Entwhistle to Miller - and they are fresh, impressive and phenomenal today.
We are all fortunate to have so many superb players to emulate and the world's best instruments to practice with (no excuses )
Happy Holidays to All!
JFT