Mean (± SE) performance when the sample size was 5 licks at ∼1 μl/lick (left) and when the sample size was increased to 7 licks at ∼1.6 μl/lick (right) as a function of Polycose concentration for the T1R2 KO (top, ○), T1R2 WT (top, ●), T1R3 KO (bottom: ○), and T1R3 WT (bottom, ●) groups.