Twitching as we fall asleep

Yes, this was an old post–but there it was, begging a response. The query in question was essentially – why do we sometimes twitch as we’re falling asleep? It was posted over 25 years ago, and I am not sure if anyone ever offered what I am about to offer as an explanation: First, we don’t always twitch as we “drop off” to sleep. But it happens from time to time. While it may be difficult to determine this, I believe it may happen if, at the moment we are about to hit the sleep waves, we move slightly. So why the twitch? Anthropologists I know offer the following explanation: For millennia, as our human ancestors developed and evolved in and around the plains of northeastern Africa, we were close to the bottom of the food chain, and there were many carnivorous dangers out there both day and night. It was for that reason that these forebears had to sleep in trees. My scientist pals say that the twitch referred to here was ingrained in us over those many thousand years as a true survival instinct–a quick response to movement while sleeping that may have resulted in falling out of the tree. In other words, the twitch is a primordial response meant to save us from plummeting to our deaths.

Quote: “It was posted over 25 years ago”
Not on this Board. What Board are you refering to?

Here is the column in question (I think.)

Correct me if I’m wrong, but I don’t believe early hominids were ever “near the bottom of the food chain”, and I’m pretty sure they didn’t sleep in trees.

You’re wrong: according to one theory

Emphasis Mine

Sleeping in trees, I don’t know.
However, evolving the behavior of twitching in one’s sleep does not seem to go with sleeping in trees. That is just opinion though.

I, too, may be wrong but I don’t believe that being prey to a few predators is the same thing as being “close to the bottom of the food chain” - it simply means you aren’t at the very top.

So, you’re implying that the food chain looks something like this?

You are obviously right, since being close to the bottom of the food chain would mean that humans were prey for plankton and the like.

Unfortunately, being fifth from the top is similar to coming in fifth in the race for the Democratic Presidential nomination. It may be that early humans simply weren’t at the very top of the food chain, but coming in at number two simply made them number two.

FWIW, I still don’t buy the idea that — as an evolutionary response to the need to sleep safely in trees — our ancestors developed the behavior of twitching like a bungee cord marionette when they fell asleep.

Absolutely no way Doc - it is something to do with nerve ends and may be a result of a high fibre diet or one low in potassium. Some people respond differently though and for some a twitch can positively make them jump out of bed and be kept unnecessarily awake for a further two hours just as they were dropping of to sleep either way it is an unfortunate condition but can be minimised if less drugs and alcohol are consumed.

Do you have any cites for these links between twiching and fibre, potassium, drugs and alchohol?