well i don't have 'scientific data' but i am pretty sure that 'toning' is more about how much your body fat percentage is, higher reps are for muscular endurance, and lower reps are for muscular strength. if there was one perfect method for hypertrophy, bodybuilding would be easy, but there isn't, as far as i know.

from what i've read and experienced, it is fairly effective to include higher and lower rep ranges in your routine. everything works, but nothing works forever.