My college girlfriend and I were both in ROTC to pay for college, though she grew to hate the fact that she had to do it. Part of ROTC is drill (learning to march in a coordinated fashion, mostly as a matter of discipline and for parades rather than for a direct military purpose).

Anyway, when we were walking around casually as civilians, I would sometimes synchronize our steps as we would do during drill. Drove her crazy when she realized what I was doing. :)

The military purpose of marching in formation goes back at least to the phalanx. Success required the phalanx to move as one. A breach in the phalanx was to be exploited by the enemy.

Gunpowder put an end to the battlefield utility of formations, but it's still useful to get the troops to operate as a unit.

> Gunpowder put an end to the battlefield utility of formations, [...]

Well, not immediately. That took close to a thousand years.

Soldiers break step when marching across a bridge, to counter sympathetic frequency induced bridge collapses.

Shouldn't most mammals, or even vertebrates do this? I would go one step further and say that probably most animals or living beings do this (the social ones anyways) after a while, and the one thing I'm remembering is the syncing clocks experiment. I would assume physically it's easier for a being to 'sync up' with it's environment (in this case other peers), since that would probably give the feeling of more control, stability & familiarity.

Sand people will march in single file, to hide their numbers. I wonder if it's similar.

Shouldn’t it be the other way around?

Humans do x just like monkeys?

That depends on the reference point.

From the human PoV We notice chimps ape us.

If Chimps were to study humans, they may also notice humans ape them and come to the conclusion that humans synchronize steps like chimpanzees do.

Us being human, then we notice they synchronize like we do.

Humans have been evolving for exactly as long as chimpanzees. To the second.

I love that statement and I'm stealing it.

The thought occurred that time dilation would result in the descendants of ISS crew members (and of their gut flora, for that matter) falling behind, but it would take a looong time in orbit to add up to a second.

Few have reproduced after being there. Have any?

I don't know, but their gut flora certainly have.

I guess failing to reproduce after would count, too.

Though chimpanzees are apes, this was my first thought as well.

what difference does it make?

At this point? -HRC

I wonder if it's to increase the chance of hearing an unexpected/out of sync footstep or other noise.

I used to do this when sneaking up on people, as a kid.

You can get as close as six inches behind somebody walking, this way, without them noticing. People don't like it.

Sounds interesting. Any sources on that?

Authors don't cite personal experiences.

[Original research]

Time to teach the chimps how to cha-cha.