Simplistic . . .
H.G. did the dual-species bit for "The Time Machine." He dumbed it way down for the limited sci-fi audience.
In his 2-volume "History of Man," he comes up with the possibilities for several sub-species, or none at all, depending upon the sociality of future generations. What he did predict was a strong possibility for a mingling of all races, and thus forming a primary race of beautifully tanned humans.
It also appears that Oliver Curry may be a bit dim-witted.