"Progenitor" is the name given to the species of former humans that have undergone genetic recombination into a creature strikingly similar to the Elves of popular culture. The name originates from the nature of the transformation, being that it transforms humans into what genetically resembles natural-born Fae prior to the onset of their pre-birth nanomachine imbuement, and was apparently given out of a sense of ironic amusement. It has attained common use amongst humans, though other terms such as "Alien", "Prog", "Elf", "Fairy" and "Knife-Ear" are used with equal frequency.
Because the process of their creation involves the complete rewriting of the genetic code, Progenitors are certainly no longer human, and technically do not fall under laws for the preservation of human rights and safety, a loophole that has alarmingly yet to be addressed by any world nation or organization. Despite this, surprisingly little beyond what can be ascertained by cursory examination is known about the Progenitor's biology, at least publicly.
Externally, Progenitors possess largely all of the traits they once had while human. Common "defects" such as allegies, poor eyesight and other ailments will be cured during transformation, while features such as height, weight, skin and hair and eye color may sometimes change on their own accord (however, this is not the norm). The most telling difference between a human and a Progenitor lies with the ears, which are in most cases much longer than a human's. Because this makes owners of Armors easy to pick out, it is common for Progenitors to grow out their hair or wear hats and other headwear to hide their non-human nature. The length of the ears varies widley between individuals, but their increased length and range of motion generally gives a Progenitor a slightly better degree of hearing and balance than a human. In addition, Progenitors have also been shown to have somdwhat easier time seeing in the dark, and possibly a marginally faster rate of healing, implying a longer natural lifespan than a modern human can expect.
Below the surface, Progenitor anatomy seems surprisingly similar to a human's. In terms of internal organs, the only major differences noticed thus far are a lack of appendix and second kidney. Their skeletal structure has a slightly higher cartilage-to-bone ratio, giving them somewhat better flexibility.