... what are the three human minor races depicted on the cover of the GURPS Traveller Humaniti book?
I don't think you should read much at all into the cover art of
GT:Humaniti. Or any of the interior art for that matter.
I don't know the entire story, perhaps only LKW and Steve Jackson know the entire story, but I was active at the SJG and JTAS fora during the period and do remember what little we were told about
GT:Humaniti.
It seems the artist originally contracted to provide art for the book was unable, for whatever reason, to fulfill that obligation. The time between when SJG learned about this and when the book was supposed to go to the printer was very short. If the book were held back in order for the art contract to be let again, the publication date would be pushed back even further.
SJG, like any good company, is quite sensitive to promised release dates, so sensitive that SJG normally avoids announcing any release dates until a product is actually in their hands.
GT;Humaniti, however, had been on the production schedule for some time, rumors were constantly circulating regarding it, and there were growing expectations/fears within the pool of potential purchasers. It was decided that
any art would be preferable to pushing the release date back further.
Another artist was contracted and, with the little time left, they produced the sketches you see in the book. There was no time for the usual "give & take" between artist and editor, there was no time for the artist to polish their work, there was no time for anything other than the admittedly rough sketches you see in the book.
Art rarely has the same "level" of canonicity text enjoys. H.G. Wells, for example, loathed the art used in the first few printings of
War of the Worlds. In the case of
GT:Humaniti and thanks to how it was produced, little if any of the art in the book should be thought of as canon.
So, answering your original question, the three figures on the cover of
GT:Humaniti don't really represent any human minor races at all.
)
