Department of Physics, Chemistry and Biology (IFM)

A traditional view suggest that primates are “visual” animals with a poorly developed sense of smell. However, recent studies suggest that the olfactory sense may be of high behavioural importance for primates. The present study used a two-choice paradigm to assess the olfactory  sensitivity for the L- and D form of the amino acids methionine, cysteine and proline for black-handed spider monkeys (Ateles geoffroyi). All animals could discriminate concentrations below 1 ppm for all amino acids, with single animals reaching even better results. For all amino acids with the exception of L-proline, individuals could reach results below 2 ppb. The chiralities did not seem to have a systematic impact on the results, although the molecular structure of a substance seemed to have an impact on threshold detection since the spider monkeys detected higher thresholds with proline, which is a substance that differ in the sense that the α-amino group is secondary, compared to methionine and cysteine. The results were compared to data collected from mice and humans and showed that the olfactory thresholds were similar for all three species. The study showed that spider monkeys have a well developed sense of smell for amino acids.

Keywords

Amino acids, olfactory detection thresholds, spider monkeys