Just some lore on the humans in this universe.

Long ago, long before making contact with other intelligent life, humans, like most, had a bit of a violent strek. They had a few noteworthy wars, WWI, WWII and WWIII, each war more violent then the last.
It was a miracle anyone on the planet survived the nuclear fallout of WWIII, but they did and now human kind has more than quadrupled their number but this doesn't mean that the consiquenses don't still linger.

Human genes are severely volatile, changing under stress. It is not uncommon for things such as puberty completely changing one eye and hair color. In accidents few have completely change their genetic makeup, though this is extremely rare and the once that this has happened to often die..

Colors that were previously only were achieved through cosmetic interference is now completely naturally produced by their body. Unnatural phenomena such as glowing under uv light and seeing colors unknown is now only rare. Disabilities new and old now affects 40% of the population and growing.

There are only a few "pure" humans left, descendants of the once that managed to escape the war before it started, though their numbers are dwindling.