This post should be equally combatable with Mothership and GLOG -- there's not much numerical content.
And also, a brief but important disclaimer about race/species in science fiction and fantasy. It's a touchy issue and rightly so. It's also an issue that's tightly wound up in actual play culture and the implied fiction of different games (e.g. whether your characters are presumed to be exceptional or drawn from a random cross section). This is not a post discussing any those things (but I'm always receptive to sensitivity concerns).
Each group of people in TTET gets a letter in the Phoenician alphabet as a name -- because they are distributed between more than a dozen planets and moons and thousands of habitats that have in many cases developed in cultural isolation for hundreds or thousands of years it's impossible to find a demonym everybody would agree on. This also isn't a post about culture -- there are too many cultures to describe.
𐤀 - ALEP
One of the most common groups of hominids and one that has for various reasons (mostly luck and geography) wielded outsized influence over the past millennium and into the present day. The polity that became the Monument Builder Empire was 𐤀 as are the Philosopher Kings and many of the Great Merchant Houses.
𐤁 - BET
Pale, webbed hands and feet, short but thick oily body hair suited for extended periods in the water, very strong lungs, strong preference for carnivory. Can hold breath for around 10 minutes and swim as long as you can walk.
𐤂 - GIML
Tall, long-limbed, and lightly built. Full range of hair and skin tones found in homo sapiens. Adapted to very low gravity. Constant bone density -- no adverse effects from extended time microgravity. Very good at climbing, leaping, and maneuvering in microgravity. Can't run for extended periods.
Origin traced to a single large de-spun rotating habitat but contact with the Monument Builders spread 𐤂 to many smaller habitats in the Low Belt. 𐤂 makes up a plurality of the peoples of the Great Merchant Houses. Behaviorally very similar to 𐤁 (and homo sapiens).
𐤃 - DALET
Heavyset and very large (100-150+kg), strong but not a great long-distance walker compared to homo sapiens. Full range of hair and skin tones found in homo sapiens. Strong preference for herbivory, many behavioral adaptations favoring larger group cooperation (for better and worse). Reroll strength and take highest. You will likely live to 100 with modern medicine. Can't run for extended periods.
𐤄 - HE
𐤅 - WAW