Terrans (or Earthers, Shìrén, etc.) are the humans who originated on Earth/Sol Three, one of three known human homeworlds. Like the Inukari and Zhdez, they were surprised to encounter other humans already among the stars, and even more surprised to learn that humanity did not organically evolve on any of the homeworlds. Unlike the other two species, they generally deny the evidence of this.

Modern Terrans have the most sexual dimorphism of any of the known species. Adult males can be considerably larger than their Inukari or Zhdez counterparts. This extends to social roles, as well: Terrans, particularly in the Terran Alliance proper, have somewhat rigid gender roles, though there has been a continuous battle against it on the part of women throughout their modern history.

Terrans have approximately the same level of physical diversity among ethnicities as the other two human species, but as with gender they have engaged in a system subjugation of certain ethnicities, with power primarily held in the hands of ethnicities deemed "white." This has ebbed and flowed, with the current Terran Union being strongly based in racism and colorism.

Terrans are the most competitive and even aggressive, both personally and as a society, of the three human species, trailing only the Gvazda. Like the Gvazda, this competitiveness led to a fairly late but steep climb in technological ability; unlike the chronically overpopulated Gvazda this tech acquisition has been focused more on weaponry than on food production. Like the Inukari, technology took a steep ecological toll on their homeworld, and this was a primary impetus for spaceflight and then starflight.

Terrans have psionic abilities at approximately the same rate as Inukari, as far as can be estimated - Terrans, even outside the Union proper, have a cultural taboo against telepathy in particular.