A Sekkari Artificial Intelligence, or A.I., was programmed into each of the many seed carriers. Its purpose is to ensure the seed carrier finds a suitable world on which to restart the Sekkari species. By means of low levels of radiation, the A.I. was able to scan members of the Atlantis expedition and appear to them in forms that would help communicate to them the situation. Because of the unique nature of the A.I.'s method of interaction, the forms taken are considered hallucinations and can only be seen by a select few of the Atlantis personnel. (SGA: "Remnants")