Is the strange reproductive process in The Twelve Kingdoms based on a myth or legend?


In The Twelve Kingdoms, babies are born from Ranka, or giant eggs that grow on
trees. Is this based on an myth or legend? Or is it just a way the author
invented to explore what happens to a society where the women do not have to
give birth? The idea of babies growing in eggs on trees seems like something
I've heard of before somewhere else, but I can't recall where.

![Ranka Tree](https://i.stack.imgur.com/XHI4I.png)




I touch on this in [my answer](https://anime.stackexchange.com/a/3478/247) to
your other question. Eastern and Buddhist myths often use the [cosmic
egg](http://en.wikipedia.org/wiki/World_egg) to explain creation. In Chinese
mythology, it is [Pangu](http://en.wikipedia.org/wiki/Pangu) who hatches from
the egg. In Hindu mythology, it is
[Brahma](http://en.wikipedia.org/wiki/Brahma#Origin). In Buddhism, Buddha
himself is depicted as hatching from the egg as seen below.

![enter image description here](https://i.stack.imgur.com/rC2En.jpg)

The myth of the [World Tree](http://en.wikipedia.org/wiki/World_tree) is
another that pervades religion.




I touch on this in [my answer](https://anime.stackexchange.com/a/3478/247) to
your other question. Eastern and Buddhist myths often use the [cosmic
egg](http://en.wikipedia.org/wiki/World_egg) to explain creation. In Chinese
mythology, it is [Pangu](http://en.wikipedia.org/wiki/Pangu) who hatches from
the egg. In Hindu mythology, it is
[Brahma](http://en.wikipedia.org/wiki/Brahma#Origin). In Buddhism, Buddha
himself is depicted as hatching from the egg as seen below.

![enter image description here](https://i.stack.imgur.com/rC2En.jpg)

The myth of the [World Tree](http://en.wikipedia.org/wiki/World_tree) is
another that pervades religion.

