The Ancients originally existed in another realm, one that is vastly different from our own. This plane of existence was bridged to ours by wormholes. When they became aware of the various species in our realm, and many of those species' aggressive tendencies, they modified several members of their own species, allowing them to live and exist in our universe. These individuals became the Ancients and they were tasked to catalogue, report, and influence the activities of the species in our universe.
After many years in our realm, however, the planet where the Ancients lived began to die. They began a search for a suitable location whose dominant species would welcome them and where the Ancients' hive could live and replenish. The Ancients only had enough power to transport their entire race one last time and because of their unique nature, they could only live on a small number of worlds. Discovering that Earth was one of these worlds, the Ancients create an elaborate simulation using the memories of the human John Crichton.
Creating what appears to be a wormhole leading to Earth, the Ancients lure John into this simulation. There, Crichton's memories and expectations play out a scenario that allows the Ancients to see how humans would respond to alien contact. Shortly after Crichton realizes that there is something very wrong about the Earth to which he's returned, an Ancient in the guise of John's father Jack Crichton explains the situation and the reason for the simulation. Having learned that humanity would not welcome an alien species on its planet, they continue their search for a new home. Unknown to Crichton at the time, "Jack" gives him subconscious knowledge of wormhole navigation. His intention is to provide Crichton with a potential way home if he proves to be worthy by unlocking that information himself. The Ancients eventually go on to discover a planet that is suitable for their needs.
Anatomy and appearanceEdit
In their true form, the Ancients are thin and bipedal with brown skin and a bug-like appearance. They have four arms; two shorter upper arms, and two longer arms that are lower on their torso. The upper arms end in lobster-like claws while the lower arms appear to have three-fingered hands. They also have several shorter tentacle-like appendages both around and on their facial area.
Little else is known, but they do have the ability to shift their appearance, seemingly able to change from their true form to that of a human being at will. This disguise does appear to be rather fragile, however, as Crichton is able to tear off "Jack"'s chest accidentally. How the Ancients appear in their home realm is unknown.
Culture and societyEdit
The Ancients have technology and knowledge that greatly exceeds anything seen in our galaxy. They have the ability to understand and use wormhole travel and navigation. Their wormhole-based technology includes at least two wormhole weapons. In their own realm, time is subject to an Ancient's will. In our own realm, they also have the ability to create extremely realistic simulations based on a subjects' memories. These are not virtual reality, but actual duplications down to identical-seeming people and materials. These simulations are limited to only what is in the subject's memory, so when Crichton realized that everyone in "Australia" was someone he had also known in his own past in America, the Ancients' duplicity was revealed.