The Super Sensational Self Tying Knot - coming soon to a crag near you!

This knot tied itself. (see story below)

self tying knot
I was climbing with a guide at Devils Tower this summer. As we prepared to descend, he realized there were a lot of people on top and it was getting hot, fast. He suggest that the couple we met and had lunch with share our rappel setup to keep the traffic moving a bit faster. Long way of saying that 4 people used our double rope rappel setup. After 3 raps to the bottom, my guide pulled the line. As I watched it come down the only knot I saw was the flat OH bend joining the ropes. Immediately after the rope hit the ground the guide exclaimed "WTF" or some such profane incredulity, and held up this knot. He took this picture.

I’ve climbed for 15 of the last 25 years and have never seen such a thing. Has anyone else experienced this? Can anyone offer an explanation?

Not that nice, but managed to get a bight of rope to make a knot in rope bag.

The infinite monkey theorem states that a monkey hitting keys at random on a typewriter keyboard for an infinite amount of time will almost surely type a given text, such as the complete works of William Shakespeare.
Infinite Monkey Theorem

I've seen a rope tie itself in a slipknot before but never something that complex. That's freakin amazing. I almost want to try and recreate it to see what's going on. A good reminder that weird shit happen in the vertical environment

I had a rope clove hitch its end to an alder bush after rappelling an ice climb last winter...

I had a rope tie a over hand knot at the last shut..... hung the cord up big time! We pulled and pulled.... finally I had to re-lead the pitch... got to the shut... wished I had a camera.

Ropes do weird things

When a rope isn't saving your life, it's trying to kill you...

Pretty sure that's a Prince Knot

I had a rope once tie my girlfriend to the bed. Weirdest thing, but she seemed to like it.

Had a rope tie a figure eye in itself as we were pulling it down halfway down the rappel of royal arches. We are lucky to have seen it before it got to high up the wall or we would have been stuck.