Recently, while re-reading the original Dune series for the umpteenth time, something caught my attention. In the first book green is the color of mourning among the Fremen:
"Chani came down the lane opened there, her elfin face set in lines of grief. She had removed her stillsuit and wore a graceful blue wraparound that exposed her thin arms. Near the shoulder on her left arm, a green kerchief had been tied. Green for mourning, Paul thought. It was one of the customs the two sons of Jamis had explained to him by indirection, telling him they wore no green because they accepted him as guardian-father."
This is still the case in the second book, Dune Messiah:
"Colors played upon the unprotected psyche: Paul's green throne had been cut from a single Hagar emerald. It suggested growing things and, out of the Fremen mythos, reflected the mourning color. It whispered that here sat he who could make you mourn -- life and death in one symbol, a clever stress of opposites."
In the third book, Children of Dune, this has changed:
"Alia still wore the yellow for mourning, the color of the sterile sun."
There are multiple other references to the yellow of mourning in the same book but no explanation for the change. At first I thought that it was because green was the color of House Atreides, but the passage from Dune Messiah shows that Paul preferred to play on that. Could it have been Alia who changed the traditional mourning color after Paul's disappearance into the desert? Alia with her preborn awareness understood the power of symbols every bit as well as Paul; it seems that she would have made no change to the traditional symbology in that regard.
The only other thing I can think of is the cultural shift among the Fremen after Paul's jihad and the acceleration of Liet-Kynes' program to change Arrakis into a green planet. Perhaps seeing their dreams begin to take shape and green plants growing openly caused the Fremen psyche to see green as a color of life. The yellow of the hot sun does make sense as color of mourning for a desert people. However, the more green there is on the planet, the more Fremen seem to lose their traditions, disciplines, and values. So again, green for mourning is still in a way appropriate.
Has anyone else any thoughts about this?