A social chemosignaling function for human handshaking.
Social chemosignaling is a part of human behavior, but how chemosignals transfer from one individual to another is unknown. In turn, humans greet each other with handshakes, but the functional antecedents of this behavior remain unclear. To ask whether handshakes are used to sample conspecific social chemosignals, we covertly filmed 271 subjects within a structured greeting event either with or without a handshake. We found that humans often sniff their own hands, and selectively increase this behavior after handshake. After handshakes within gender, subjects increased sniffing of their own right shaking hand by more than 100%. In contrast, after handshakes across gender, subjects increased sniffing of their own left non-shaking hand by more than 100%. Tainting participants with unnoticed odors significantly altered the effects, thus verifying their olfactory nature. Thus, handshaking may functionally serve active yet subliminal social chemosignaling, which likely plays a large role in ongoing human behavior.
Department of Neurobiology, Weizmann Institute of Science, Rehovot, Israel.
Idan
I
Frumin
Department of Neurobiology, Weizmann Institute of Science, Rehovot, Israel.
Ofer
O
Perl
Department of Neurobiology, Weizmann Institute of Science, Rehovot, Israel.
Yaara
Y
Endevelt-Shapira
Department of Neurobiology, Weizmann Institute of Science, Rehovot, Israel.
Ami
A
Eisen
Department of Neurobiology, Weizmann Institute of Science, Rehovot, Israel.
Neetai
N
Eshel
Department of Neurobiology, Weizmann Institute of Science, Rehovot, Israel.
Iris
I
Heller
Department of Neurobiology, Weizmann Institute of Science, Rehovot, Israel.
Maya
M
Shemesh
Department of Neurobiology, Weizmann Institute of Science, Rehovot, Israel.
Aharon
A
Ravia
Department of Neurobiology, Weizmann Institute of Science, Rehovot, Israel.
Lee
L
Sela
Department of Neurobiology, Weizmann Institute of Science, Rehovot, Israel.
Anat
A
Arzi
Department of Neurobiology, Weizmann Institute of Science, Rehovot, Israel.
Noam
N
Sobel
D000328:Adult; D005260:Female; D006225:Hand; D006801:Humans; D008297:Male; D009812:Odorants; D015398:Signal Transduction; D012903:Smell; D012919:Social Behavior
handshaking; human; neuroscience; pheromones; sniffing; social chemosignaling