[mnehring]

That's why I mentioned also some sort of binding ritual as well. Just a guess, but it may have been a less severe case but it triggered people of the time to think it was 'special' and they used bindings to exaggerate. Head binding (Artificial cranial deformation) was popular in ancient South and Central American cultures.

http://ancientstandard.com/2010/12/20/why-some-ancient-south-american-skulls-have-such-strange-shapes/

Unfortunately so many people really want to have some sort of alien or demonic (or some combination there of) answer, they completely dismiss the simplest and most logical answers.

Some example of cranial deformation bindings on skulls found in South America.

Here is a painting from the mid-1800s by an explorer (Paul Kane) who witnessed this still in practice.

[Cvengr]

Then again, such a ritual probably had a reason behind it. Perhaps such beings existed and the ritual was performed to emulate the experience others had with them. Might have even been a spiritual experience, but memorable nonetheless.

[Chode]

the question begs as to why they did the binding... what were they trying to imitate???

[BreezyDog]

Well then... you have proved to me that the skull in question is nothing special. Thanks!