Aliens on the TV show Earth Final Conflict. A throw back to before the Taelons and Jaridians diveraged as seperate species. They are humanoid looking but have laser claws that protrude out of their fingers which they stab into people's chests to suck the life force out of them. Atavus' are very evil and highly sexual creatures.
When Taelons are seperated from the commonality they devolve into Atavus.