Olfactory Discrimination Ability of Asian Elephants (Elephas maximus) forStructurally Related Odorants
2013 (English)In: Chemical Senses, ISSN 0379-864X, E-ISSN 1464-3553, Vol. 38, no 2, 107-118 p.Article in journal (Refereed) Published
Using a food-rewarded two-choice instrumental conditioning paradigm, we assessed the ability of Asian elephants, Elephasmaximus, to discriminate between 2 sets of structurally related odorants. We found that the animals successfully discriminatedbetween all 12 odor pairs involving members of homologous series of aliphatic 1-alcohols, n-aldehydes, 2-ketones,and n-carboxylic acids even when the stimuli differed from each other by only 1 carbon. With all 4 chemical classes, the elephantsdisplayed a positive correlation between discrimination performance and structural similarity of odorants in terms ofdifferences in carbon chain length. The animals also successfully discriminated between all 12 enantiomeric odor pairs tested.An analysis of odor structure–activity relationships suggests that a combination of molecular structural properties rather thana single molecular feature may be responsible for the discriminability of enantiomers. Compared with other species testedpreviously on the same sets of odor pairs (or on subsets thereof), the Asian elephants performed at least as well as miceand clearly better than human subjects, squirrel monkeys, pigtail macaques, South African fur seals, and honeybees. Furthercomparisons suggest that neither the relative nor the absolute size of the olfactory bulbs appear to be reliable predictors ofbetween-species differences in olfactory discrimination capabilities. In contrast, we found a positive correlation between thenumber of functional olfactory receptor genes and the proportion of discriminable enantiomeric odor pairs. Taken together,the results of the present study support the notion that the sense of smell may play an important role in regulating thebehavior of Asian elephants.
Place, publisher, year, edition, pages
Oxford: Oxford University Press, 2013. Vol. 38, no 2, 107-118 p.
aliphatic odorants, Asian elephants, Elephas maximus, enantiomers, olfactory discrimination
IdentifiersURN: urn:nbn:se:liu:diva-86975DOI: 10.1093/chemse/bjs097ISI: 000313128400001OAI: oai:DiVA.org:liu-86975DiVA: diva2:583967