I’ve never experienced a flash mob, but I thoroughly enjoy watching videos of this "what??" phenomenon.
Usually in a public space and apparently spontaneous (though probably well-rehearsed,) one or a few individuals begin playing instruments or singing or performing an attention-grabbing dance routine.
Others join them, arriving from all directions, and then more and more performers, and consequently, more and more on-lookers.
And then, they all just fade away.
This reminds me of crows.
Now and then, seemly spontaneously, one or two crows appear and start circling and singing (OK, I use that term loosely — cawing. Cawing raucously.
Almost immediately, out of nowhere, other crows start flying in from all directions, joining in the gyrating group and cawing stridently. Then, more crows… and even more.
Actually, it’s not spontaneous.
One crow has probably located a raven, or an owl, or maybe a hawk — the enemies!
Unlike a human flash mob, the crows are not trying to draw a happy crowd, but instead encouraging the hapless intruder to move along so the crows will need not compete for food or nest sites, or risk predation.
Some speculate that by locating and harassing a potential predator, the crows are teaching their young to recognize the enemy.
Or, maybe the behavior is just an instinct-driven response known by ornithologists as interspecific aggression.
The behavior has a name. It’s called mobbing, and the group of brash dancing crows is called a mob.
