Myth of the Egg song

Here's a topic I am sure appeals to almost nobody at all: but I am totally into it!
What's with the long-held misconceptions and beliefs surrounding a hen's laying song?!

I am speaking about the sound (known to country chicken types) as the "egg song"--a crazy squawking noise made by a hen caught up in the moment of her own egg laying.
When I first heard my own chickens producing said "song" I thought--well that's the sound of childbirth !!....But it's more rhythmic than that... akin to a poultry call of the wild (sounds like: squawk, squawk, squawk, squuuaaakkk!) The song is repeated quite a few times and freakishly loud--especially for a quiet neighborhood, that may or may not allow the harboring of poultry ;)
My trusty online chicken forums often discuss the "egg song" --usually in the context of someone's chicken getting ready to lay an egg...But my problem with this is--that the purpose of the song seems lost on folks. If you attempt to google "why the egg song" the most common answer is: "the chicken is proud of her egg, thus announces it". Now what kind of ass backwards Darwinism is that???
What animal "announces" their precious little baby-to-be to the predators of the world--especially an animal who's only means of defense seems to be "panic and run"..???

So I continued to cruise the internet for more info. I gathered the history of the chicken  begins in the jungle (which makes sense--their noises are tropical sounding!) My own theory was that the "jungle chickens" try to locate their mate with said song (the chicken doesn't really know if her egg is fertilized or not, and may need his assistance as she begins her long brooding process). And sure enough, anecdotal stories point exactly to that--if you have a rooster at home, he will respond to the egg song! I even read accounts of the rooster arriving with cabbage in his beak to feed the laying hen after the "song" !! Now, if only this more reasonable reason for the egg song would  become public knowledge!!!...I wouldn't need to hear about the "silly proud chickens" anymore!!