G Model NSR-3839; No. of Pages 9
ARTICLE IN PRESS Neuroscience Research xxx (2015) xxx–xxx
Contents lists available at ScienceDirect
Neuroscience Research journal homepage: www.elsevier.com/locate/neures
Spider monkeys (Ateles geoffroyi) are less sensitive to the odor of aliphatic ketones than to the odor of other classes of aliphatic compounds Moa Eliasson a , Laura Teresa Hernandez Salazar b , Matthias Laska a,∗ a b
IFM Biology, Linköping University, 581 83 Linköping, Sweden Instituto de Neuro-Etologia, Universidad Veracruzana, Xalapa, Veracruz, Mexico
a r t i c l e
i n f o
Article history: Received 19 February 2015 Received in revised form 10 May 2015 Accepted 29 May 2015 Available online xxx Keywords: Olfactory detection thresholds Aliphatic ketones Odor structure–activity relationships Spider monkeys Ateles geoffroyi
a b s t r a c t Aliphatic ketones are widely present in body-borne and food odors of primates. Therefore, we used an operant conditioning paradigm and determined olfactory detection thresholds in four spider monkeys for a homologous series of aliphatic 2-ketones (2-butanone to 2-nonanone) and two of their isomers (3- and 4-heptanone). We found that, with the exception of the two shortest-chained ketones, all animals detected concentrations 0.05). In contrast, the spider monkeys were significantly less sensitive for 2-ketones compared to human subjects (Mann–Whitney U-test, z = −3.22, P < 0.01) and mice (Mann–Whitney U-test, z = −5.87, P < 0.001). In the latter case the ranges of threshold values for the 2-ketones did not even overlap between the two species with any of the six odorants.
Fig. 7 compares the olfactory detection thresholds of the spider monkeys for the three heptanones tested here with threshold data obtained in earlier studies with the same odorants in other species of mammals (squirrel monkeys and pigtail macaques: Laska et al., 2005b; mice: Laska, 2014; human subjects: van Gemert, 2011). The spider monkeys were significantly more sensitive for the heptanones compared to squirrel monkeys (Mann–Whitney U-test, z = −2.60, P < 0.01) and did not differ significantly in their olfactory sensitivity with these odorants compared to pigtail macaques (Mann–Whitney U-test, z = −0.44, P > 0.05). In contrast, the spider monkeys were significantly less sensitive for the heptanones compared to human subjects (Mann–Whitney U-test, z = -3.71,
Please cite this article in press as: Eliasson, M., et al., Spider monkeys (Ateles geoffroyi) are less sensitive to the odor of aliphatic ketones than to the odor of other classes of aliphatic compounds. Neurosci. Res. (2015), http://dx.doi.org/10.1016/j.neures.2015.05.008
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Fig. 3. Olfactory detection thresholds of spider monkeys as a function of carbon chain length of the aliphatic 2-ketones tested. Each symbol represents the threshold value of an individual animal. The solid line indicates the regression with the best goodness-of-fit according to second order polynomial regression analysis.
P < 0.001) and mice (Mann–Whitney U-test, z = −3.63, P < 0.001). Here, too, the ranges of threshold values for the heptanones did not even overlap between spider monkeys and mice with any of the three odorants.
Fig. 5. Comparison of the olfactory detection threshold values of the spider monkeys for aliphatic 2-ketones and those for aliphatic 1-alcohols, n-aldehydes, n-acetic esters, and n-carboxylic acids sharing the same carbon chain length. Data points of all five chemical classes represent the highest and the lowest threshold values of individual animals reported in the literature (1-alcohols and n-aldehydes: Laska et al., 2006b; n-acetic esters: Hernandez Salazar et al., 2003; n-carboxylic acids: Laska et al., 2004) and, for 2-ketones, in the present study.
4. Discussion The results of the present study demonstrate that spider monkeys have a well-developed olfactory sensitivity for aliphatic ketones and, with only few exceptions, are able to detect members of this chemical class at concentrations
ARTICLE IN PRESS Neuroscience Research xxx (2015) xxx–xxx
Contents lists available at ScienceDirect
Neuroscience Research journal homepage: www.elsevier.com/locate/neures
Spider monkeys (Ateles geoffroyi) are less sensitive to the odor of aliphatic ketones than to the odor of other classes of aliphatic compounds Moa Eliasson a , Laura Teresa Hernandez Salazar b , Matthias Laska a,∗ a b
IFM Biology, Linköping University, 581 83 Linköping, Sweden Instituto de Neuro-Etologia, Universidad Veracruzana, Xalapa, Veracruz, Mexico
a r t i c l e
i n f o
Article history: Received 19 February 2015 Received in revised form 10 May 2015 Accepted 29 May 2015 Available online xxx Keywords: Olfactory detection thresholds Aliphatic ketones Odor structure–activity relationships Spider monkeys Ateles geoffroyi
a b s t r a c t Aliphatic ketones are widely present in body-borne and food odors of primates. Therefore, we used an operant conditioning paradigm and determined olfactory detection thresholds in four spider monkeys for a homologous series of aliphatic 2-ketones (2-butanone to 2-nonanone) and two of their isomers (3- and 4-heptanone). We found that, with the exception of the two shortest-chained ketones, all animals detected concentrations 0.05). In contrast, the spider monkeys were significantly less sensitive for 2-ketones compared to human subjects (Mann–Whitney U-test, z = −3.22, P < 0.01) and mice (Mann–Whitney U-test, z = −5.87, P < 0.001). In the latter case the ranges of threshold values for the 2-ketones did not even overlap between the two species with any of the six odorants.
Fig. 7 compares the olfactory detection thresholds of the spider monkeys for the three heptanones tested here with threshold data obtained in earlier studies with the same odorants in other species of mammals (squirrel monkeys and pigtail macaques: Laska et al., 2005b; mice: Laska, 2014; human subjects: van Gemert, 2011). The spider monkeys were significantly more sensitive for the heptanones compared to squirrel monkeys (Mann–Whitney U-test, z = −2.60, P < 0.01) and did not differ significantly in their olfactory sensitivity with these odorants compared to pigtail macaques (Mann–Whitney U-test, z = −0.44, P > 0.05). In contrast, the spider monkeys were significantly less sensitive for the heptanones compared to human subjects (Mann–Whitney U-test, z = -3.71,
Please cite this article in press as: Eliasson, M., et al., Spider monkeys (Ateles geoffroyi) are less sensitive to the odor of aliphatic ketones than to the odor of other classes of aliphatic compounds. Neurosci. Res. (2015), http://dx.doi.org/10.1016/j.neures.2015.05.008
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ARTICLE IN PRESS M. Eliasson et al. / Neuroscience Research xxx (2015) xxx–xxx
Fig. 3. Olfactory detection thresholds of spider monkeys as a function of carbon chain length of the aliphatic 2-ketones tested. Each symbol represents the threshold value of an individual animal. The solid line indicates the regression with the best goodness-of-fit according to second order polynomial regression analysis.
P < 0.001) and mice (Mann–Whitney U-test, z = −3.63, P < 0.001). Here, too, the ranges of threshold values for the heptanones did not even overlap between spider monkeys and mice with any of the three odorants.
Fig. 5. Comparison of the olfactory detection threshold values of the spider monkeys for aliphatic 2-ketones and those for aliphatic 1-alcohols, n-aldehydes, n-acetic esters, and n-carboxylic acids sharing the same carbon chain length. Data points of all five chemical classes represent the highest and the lowest threshold values of individual animals reported in the literature (1-alcohols and n-aldehydes: Laska et al., 2006b; n-acetic esters: Hernandez Salazar et al., 2003; n-carboxylic acids: Laska et al., 2004) and, for 2-ketones, in the present study.
4. Discussion The results of the present study demonstrate that spider monkeys have a well-developed olfactory sensitivity for aliphatic ketones and, with only few exceptions, are able to detect members of this chemical class at concentrations
