yeah I follow what you mean, I thought you meant something else. Its like stretching silly putty.

It's a cranial deformation process which they start at infancy while the skull is soft. The process lasts for a few years actually stretching the cranium until they get the desired result.

Do you have any other links about the generational differences or timelines? It's been a few years however I recall watching or reading something on many of these elongated skulls and how some more recent ones were linked to more modern day tribes that still use headwrapping starting at infancy. It was said the belief is that this somehow adds brain capacity in reflection of the gods. Meaning not all of these skulls that were examined are the same which was at that time thought to have been a different species.

Funnily enough looking into the giants bit, the second link you posted. There is a lot of information on skeletal giant remains that have been found all over the world. IIRC most recent finds were handed over to the Smithsonian which have since been locked away.