The Human, or Homo Sapiens, are generally the most common race of space personnel you'll encounter. They're more or less the "jack of all trades" of the different races, as while they don't have any glaring advantages (aside from numbers and a superiority comples) they also don't have any glaring disadvantages as well. On Asimov A.I.s, they are the A.I.s precious special little babies who can do no wrong. On Crewsimov, they're the A.I.s precious special little babies but only if they're crewmembers.
In terms of how they act, again, they're a wild card. Some, well actually most, are xenophobic. Some are perfectly well-adjusted. Some are just assholes, and some are just wackadoodoo insane and it's a wonder NT hired them.