Taste responsiveness of chimpanzees (Pan troglodytes) and black-handed spider monkeys (Ateles geoffroyi) to eight substances tasting sweet to humans.

Using a two-bottle choice test of short duration, we determined taste preference thresholds for eight substances tasting sweet to humans in three chimpanzees (<i>Pan troglodytes) </i> and four black-handed spider monkeys (<i>Ateles geoffroyi)</i>. We found that the chimpanzees significantly preferred concentrations as low as 100-500 mM galactose, 250 mM sorbitol, 0.5-2 mM acesulfame K, 0.5-2.5 mM alitame, 0.5 mM aspartame, 0.2-2 mM sodium saccharin, 0.001-0.2 mM thaumatin, and 0.0025-0.005 mM monellin over tap water. The spider monkeys displayed lower taste preference threshold values, and thus a higher sensitivity than the chimpanzees, with five of the eight substances (2-20 mM galactose, 20-50 mM sorbitol, 0.2-1 mM acesulfame K, 0.002-0.005 mM alitame, and 0.002-0.5 mM sodium saccharin), but were generally unable to perceive the sweetness of the remaining three substances (aspartame, thaumatin, and monellin). The ranking order of sweetening potency of the eight taste substances used here correlates significantly between...