An excerpt from an essay published by Arak'Antos, professor of Humanology at a renowned university.
The sheer scope of humanity's variety necessitated the creation of an entirely new field of study. Never before in the history of galactic civilization has any one race been so uniquely bizarre that they could not be encompassed in standard xenobiology and xenopsychology courses. Even before the body modifications that they are so fond of, it can often be different to tell that two humans belong to the same race, as they can differ in every plausible physical and psychological way.
Their skins’ pigmentation ranges from a deep brown that approaches true black, to rare individuals that possess no pigments whatsoever, leaving them entirely white. They can have hair covering most of their body, or have none at all. They can range in height at adulthood from four feet tall to eight feet tall, with some notable exceptions on both ends of the spectrum.
The psychological differences are just as pronounced. Several humans have agreed to extended observation as part of my ongoing research into their nuances, and the findings have been striking. One volunteer shunned physical contact at nearly any cost, and avoided social interaction whenever plausible. He would sometimes sit as his computer in silence for long periods of time, once going nearly three days without moving, without even eating. I did not interrupt, as I wished the observation to be impartial, but once I felt I had collected enough data, I asked him about it. Was it difficult to go that long without nourishment or rest? His response:
"Not really? I guess I just lost track of time."
This has been observed in other humans as well, to lesser degrees, with them being able to "lose track of time" as they focus on a single task, be it something as trivial as assembling a model or reading a book, for hours. Inversely, I have also observed humans who would be, simultaneously, working on a report, listening to music, watching video, and participating in one or more conversations through voice communications or text programs. When denied one or more of these stimulants, they would become noticeably on-edge, and their productivity would, somehow, suffer.
There is no known correlation between mental and physical attributes, either. Every few months I see some naïve young researcher publish a paper that "proves" a link between human appearances and behavior patterns, only for humans to "come out of the woodwork" and present themselves as living evidence of the falsity of their claim.
In short, no matter how much we study humans, only the most basic of understandings can be applied to them as a species. To understand a given human, one must study that specific human.
