Why men in uniform march in unison

In what could shed light on why soldiers march in step, researchers have found that men who walk in unison judge potential threats as less formidable than men who walk alone.

The act of marching itself makes the soldiers see potential enemies as less frightening, the study suggested.

"Humans find synchronous behaviour very rewarding, whether people are performing religious rituals or performing the wave during football games," said Daniel Fessler, an evolutionary anthropologist at University of California, Los Angeles.

For the study, the researchers recruited 96 men and asked them to walk 244 metres alongside another man, who was actually an employee working with the researchers.

In half of the cases, the men were told to walk normally while the rest were asked to walk in unison with the other man.

After walking, the men were shown an image of an angry male face. The researchers then asked them to estimate the man's height, his overall body size and his muscularity.

The men who had synchronised their walk rated the angry man as shorter and smaller than the men who had walked naturally, Live Science reported.

The study appeared in the journal Biology Letters.