The resonances of an acoustic guitar of course remain coupled to the string vibration picked up by any pickup. The harmonics in the sound of the acoustic guitar are directly coincident with the harmonics in the strings and thus are also picked up by the pickups.

Now it of course depends on position and characteristics of the pickup whether the fine details aren't completely blotted out by whatever harmonics the pickup itself adds: for magnetic pickups, additional harmonics are significant and may well mask most effect's of the instrument's acoustics. For pickups that are basically microphones and deliver a mostly linear response, any harmonics in the result are also present in the string vibration.

The resonances of an acoustic guitar of course remain coupled to the string vibration picked up by any pickup. The harmonics in the sound of the acoustic guitar are directly coincident with the harmonics in the strings and thus are also picked up by the pickups.

Now it of course depends on position and characteristics of the pickup whether the fine details aren't completely blotted out by whatever harmonics the pickup itself adds: for magnetic pickups, additional harmonics are significant and may well mask most effects of the instrument's acoustics. For pickups that are basically microphones and deliver a mostly linear response, any harmonics in the result are also present in the string vibration.