Adam
Adam was a member of the human race created by the First Civilization.
Adam and another human named Eve rebelled against the First Civilization. They stole one of their "Apples of Eden" and tried to escape Eden, before they were stopped by something unknown.
Some may think that Adam's DNA line continued through the Assassins Altaïr Ibn-La'Ahad, Ezio Auditore da Firenze and Desmond Miles, for some may think he was immune to the Pieces of Eden, although this is not certain, since the sense of knowledge (and the immunity to the artifacts) was only passed to mankind after the catastrophe (and so, after the war and long after Adam and Eve escape), as said by Juno, "After, when the world became undone, we tried to pass it (the sixth sense) through the blood. Tried to join you with us", meaning that there is no certain way to establish such immunity/connection. Nevertheless the First Civilization's attempts did indeed succeed in Desmond allowing him his sixth sense (Eagle Vision), and the response he has with the Apple in the end of Assassin's Creed: Brotherhood.
Lineage
The only definite descendants of Adam are Desmond Miles, Clay Kaczmarek (Subject 16) and William Miles in the Assassin's Creed Universe. The is so because:
- Ezio is the common ancestor of Desmond and Clay (Subject 16)[1] (seen where Lucy finds the match at Abstergo in the beginning of Assassin's Creed II)
- Adam is related to Clay as he can access Adam's memories and shows them to Desmond in The Truth video
- Therefore Desmond is related to Clay
- As Desmond's father William Miles must be related to Clay
Source