The primordial Goa'uld of P3X-888 were predators that evolved for millions of years in the prehistoric oceans. Snake-like vertebrates with blue blood, this early species had wing-like appendages, allowing them to leap over distances, and naquadah did not become a part of their physical makeup until later in their evolution. Eventually, they learned to take the indigenous aboriginal Unas as hosts whom they could control. Those who took hosts learned to use the stargate and left the planet, becoming a parasitic race of conquerors.
Goa'uld larvae are produced by queens, such as Hathor, who use the DNA from the intended host species to ensure compatibility. Symbiote queens produce large egg sacs and are able to fertilize their own eggs, thus reproduction is essentially an asexual process. Goa'uld offspring are born evil, with the genetic memory and the intellect and collective knowledge of their lineage which is passed on voluntarily by the queen who bore them.
New larvae depend upon a natural water environment, and they mature as snake-like symbiotes in the pouch of a Jaffa for 7 to 8 years until they are ready to take a host. Prior to the process of incubating Goa'uld symbiotes within the Jaffa, the blending of a Goa'uld and its host had only a 50% chance of success. The Jaffa were created for the very purpose of improving the ability of the symbiote to take human hosts. Symbiotes do not have a gender, but take on the gender of the host.
The Unas, and other ancient species, were taken as the first hosts, but humans have since become the preferred host species. A symbiote is only fully capable of communicating the knowledge with which it was born once it takes a host, which is its primal instinctual behavior. The mature symbiote usually enters a host through the back of the neck, since it does not wish to remember the horror on the host's face each time it looks in a mirror. The symbiote wraps itself around the victim's spine, and attaches to the brain stem, taking control of the body and intermingling its mind with that of the host. The melding, or blending, of the symbiote and host may take some time, depending on certain conditions such as the maturity of the symbiote.
Once in control, a symbiote is capable of selectively remaining dormant or active, thus in some cases a host may be unaware of the symbiote within him. The symbiote also retains the ability to exhibit or conceal its personality and characteristic glowing eyes and deep voice as it chooses. However, while a mature symbiote can take control of the host body at will, the reverse is not true, and the host remains suppressed, only able to emerge if the symbiote permits. The symbiote has access to all the knowledge of the host, and something of the host does survive, often aware of the symbiote's actions beyond his control, but in a few cases retaining the ability to exert a subtle influence over the Goa'uld's actions. It is possible for a symbiote to change from one host to another, however a symbiote cannot survive outside a host for long. A symbiote introduces naquadah into the host's system, which can be detected by other Goa'uld. It also grants remarkable healing and regenerative powers, immunity from a host of diseases, disabilities, poisons, and biological agents, and an extended life span up to 400 years in each new host, or thousands of years with the use of a sarcophagus. Goa'uld hosts do not mate, since the human child of two Goa'uld hosts, known as Harsesis, would contain all the knowledge of the Goa'uld, and is forbidden.
A symbiote will die if its injuries are too severe to heal. When a symbiote dies, it releases toxins which in most cases will kill the host. It is possible to forcibly remove a symbiote by instantly killing it before the toxins are released, however this is a delicate procedure that is often unsuccessful. A symbiote can choose to prevent the host from dying, however it requires a certain amount of energy and a conscious effort to prevent the release of toxins, a selfless act which is more typical of a Tok'ra than of a Goa'uld. If a host survives the death of its symbiote, the symbiote will decay and be absorbed by the host body, leaving behind a unique protein marker which identifies the individual as having been a host. Many of the genetic memories of the Goa'uld may also remain in the host after the symbiote has been removed, however these are often suppressed and difficult to access.
The Goa'uld are violent, arrogant, and parasitic, and have stolen all their technology from other races. They are ruthless in battle, and will annihilate that which they cannot enslave or control. Their society is feudal, with thousands of Goa'uld in general, but only dozens at the rank of System Lord. They continuously compete for power, and have been known to engage in sacred ritual cannibalism, thus keeping in check the size of the population and the competition for dominance. Historically, their greatest weaknesses have been the feudal nature of their society, and their arrogance.
Once, Goa'uld numbers were very few. According to ancient legend, Ra's race was dying. He survived by taking over the body of a human host, a young Egyptian boy, and he played the role of the sun god, using the religion of the ancient Egyptians to enslave them and the people of Abydos. They believed he was the last of his kind, but as other Goa'uld took human hosts, their numbers grew. They ruled by force, and eventually controlled many hundreds of worlds.
See Also: Goa'uld Pantheon
Cross Reference: Amaterasu, Amaunet, Anubis, Apophis, Ashrak, Athena, Ba'al, Bastet, Bynarr, Camulus, Adrian Conrad, Cronus, Kianna Cyr, Dakara, Etins, Goa'uld Language, Harsesis, Hathor, Heru'ur, Imhotep, Isis, Jaffa, Junior, Kali, Klorel, Kull Warrior, Linvris, Marduk, Moloc, Morrigan, Mot, Naquadah, Nefertem, Nerus, Nightwalkers, Nirrti, Olokun, Osiris, P3X-888, Pelops, Qetesh, Ra, Ramius, Sarcophagus, Sekhmet, Selkhet, Seth, Shak'ran, Sokar, Svarog, Symbiote Poison, System Lords, Tanith, Telchak, Terok, Thoth, Tilgath, Tok'ra, Trust, Unas, Yu, Zipacna
Children of the Gods
Significant Episode Reference: The Enemy Within, In the Line of Duty, Secrets, The Tok'ra, Forever in a Day, Crossroads, The First Ones, Summit, Last Stand, Cure, Threads, Memento Mori, Dominion