Handshaking and hand-smelling: on the potential role of handshake greeting in human olfactory communication.

Citation

Roberts S, Singleton FP, Culpepper PD, Sorokowski P, Sorokowska A & Havlicek J (2023) Handshaking and hand-smelling: on the potential role of handshake greeting in human olfactory communication.. In: Schaal B, Rekow D, Keller M & Damon F (eds.) Chemical Signals in Vertebrates 15. Cham, Switzerland: Springer, pp. 257-269. https://doi.org/10.1007/978-3-031-35159-4_14

Abstract
In many species, meetings between individuals are characterised by olfactory investigation. This enables individual discrimination and shapes subsequent social decisions. A recent study claimed that human handshake greetings have a similar role, suggesting that people often smell their hands after a handshake. Here we describe two studies that aimed to further test this idea. We observed differences in face-touching frequency following a handshake, apparently influenced by social context. In a public situation, during a graduation ceremony, rates of face-touching were low compared to a more private setting following a social interaction. In both contexts, however, face-touching was more frequent with the non-shaking (left) hand than the shaking (right) hand. In the private setting, nose touching was more common with the left hand. These results do not lend strong support to the idea that hand-smelling is a common form of olfactory assessment following a handshake greeting. In addition, perceptual tests suggest that individual discrimination of hand odour may be less effective than for axillary odour. However, we found that individual differences in hand odours do overlap with those in axillary odours, suggesting the potential for hand odour to contribute to individual assessment on those occasions when hands are smelled.

Keywords
Odour/Odor; Smell; Sniffing; Social perception; Human behaviour