Why Do People Shake Hands?

Most of us follow customs and manners without stopping to think why we do them. For example, why do people shake hands? Luckily, the question occurred to some researchers at Weizmann Institute of Science. The researchers observed 153 volunteers and discovered that people tend to sniff their own hands after shaking hands with another person, similar to the way dogs test each other’s scents. The study indicates that humans may be using social chemosignalling far more than we assume.The researchers wanted to better understand how humans transmit and use chemosensory signals. They looked at one of the most common ways in which humans touch one another– handshakes. Simple observation showed that after a handshake, people generally touched their face with the same hand. However, researchers needed to confirm whether there was actual smelling taking place. So they attached instruments to the volunteers in order to measure airflow to the nose. The study showed that after shaking hands, volunteers smelled their hand, similar to the way that dogs and rats use scent for signalling.

More about handshaking:

Handshaking is believed to date back to 5th Century Greece.
Handshakes transfer the chemicals squalene and hexadecanoic acid.
Handshake etiquette varies from country to country. Some countries prefer a firm handshake, while others a weak one.