It seems like when writing about non-human races, it's common to capitalize the species name. For example, the Romulan ship, the Vulcan engineer, etc. However, when you're talking about a human, it seems odd to write the Human engineer. But it also seems weird to write about the Vulcan engineer, and then the human engineer right afterward, using a different capitalization pattern.
Nationalities/Race: Capitalize the proper names of nationalities, races, tribes, etc.: French, Caucasian, Mataponi, Zulu. However, lowercase black, white.
So, if you talk about someone like, "He's a French propagandist.", you're stating the person's nationality. It takes a capital letter.
In the case of humans, it depends on what you're talking about. "This is a human flaw." and "This Human has flaws." So in short, if you're generalizing, "This is a human flaw.", no capital letter is needed. If you're specifying/pointing at someone in particular, it should take a capital letter.
The golden rule here is consistency.
That's how I use capitalization as I understand it.
I see what you guys are saying. I understand the grammar rules, and now that you point it out, it seems obvious. I guess it's more of an odd context thing since the word human is usually used in cases where it wouldn't be capitalized. Actually, except when dealing with other species, it seems like it almost never would be used in that way.