The Preservationists was a vigilante group of Humans that developed after the threat of the Atavus emerged on Earth. They vehemently believed in mankinds superiority and that human DNA was sacred. Furthermore, they opposed the governments plans at developing a cure for the Hybrid threat - instead, they sought to apprehend these individuals whereupon they were placed on trial and ultimately executed. They were noted for having sympathizers everywhere ranging from government positions to even the military.
FBI under Director Hubble Urick attempted to track down the group but failed. They were responsible for the abduction of former Acting Director of the FBI Ryan Patrichio from a maximum security prison where they put him on trial for his involvement with the Atavus. He was found guilty and executed with the entire event being broadcast on television. Following that act, intelligence determined that they were targeting Renee Palmer as well. (Episode: Subversion)