Behavioral study in the gray mouse lemur (Microcebus murinus) using compounds considered sweet by humans

Area of Science:

• Primate sensory perception
• Comparative taste physiology
• Chemosensation research

Background:

• The gray mouse lemur (Microcebus murinus) is a small primate native to Madagascar.
• Understanding taste perception in non-human primates provides insights into evolutionary biology and sensory systems.
• Previous studies have investigated taste-nerve responses in M. murinus, but comprehensive preference data for sweet compounds were lacking.

Purpose of the Study:

• To determine the sweet taste preferences of the gray mouse lemur (Microcebus murinus).
• To compare the sweet taste perception of M. murinus with human perception.
• To explore the phylogenetic implications of taste receptor evolution in primates.

Main Methods:

• Two-bottle preference (TBP) tests were conducted using 18 different compounds perceived as sweet by humans.
• The study involved adult gray mouse lemurs (Microcebus murinus).
• Preference data were analyzed to identify compounds that were preferred, rejected, or showed no preference.

Main Results:

• M. murinus preferred only six of the 18 tested compounds: D-tryptophan, dulcin, fructose, sucrose, SC45647, and xylitol.
• The lemurs showed no preference or rejection for acesulfame-K, alitame, aspartame, N-4-cyanophenyl-N'-cyanoguanidineacetate (CCGA), cyanosuosan, cyclamate, monellin, saccharin, suosan, super-aspartame, N-trifluoroacetyl-L-glutamyl-4-aminophenylcarbonitrile (TGC), and thaumatin.
• These findings, combined with prior taste-nerve data, suggest that some compounds may not taste sweet or may have an aversive taste component for M. murinus.

Conclusions:

• Gray mouse lemurs exhibit a specific sweet taste profile that differs significantly from humans.
• The results highlight the variability in sweet taste perception across primate species.
• The study contributes to understanding the evolution of taste systems and chemosensation in primates.