Why are fermions and bosons still referred to as fundamental particles, rather than strings (or branes, since strings are merely 1-branes)?
And before people simply say that it's called string THEORY for a reason, I'd rebut that quarks too have not been directly observed (although we do at least understand that it's due to the colour force), so I'd argue there is almost as much evidence for strings and branes as there is for other compound subatomic particles (particularly following the observed negative correlation between discrepancy between theoretical and experimental results and accuracy of mathematical constants a few weeks ago in proton-proton collisions at CERN's LHC).