Re: Why no comment on the number of human species?
I've begun to look at humans as being a fairly common species in the Star Trek Universe, with Terrans being a race of humans that originated from Earth.
You can perhaps call Romulans and Mintakans as "Vulcanian" races perhaps. There are likely quite a few other races that might resemble Vulcans in appearance, but not in demeanor or fashion sense (no bowl haircuts).
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