Movie Bios! (Xenomorph, Alien)
"I admire its purity."
The Xenomorph (Latin, Internecivus raptus, “murderous, deadly” and “seized”), better known as the Alien, are an extraterrestrial, endoparasitoid species with multiple life cycles, possibly originating from the planet Proteus (also known as Xenomorph Prime). One of the most deadly of all known alien species, these creatures need a host organism in order to reproduce. The appearance of the Xenomorph varies depending on its host. The human phenotype is generally around 7–8 feet, and roughly 136.0 to 181.4 kilograms with a long, muscular tail and large, curved, oblong head. The Queen of the species is generally twice as large and possesses superior speed, strength and intelligence. The term Xenomorph is derived from the Greek words xeno (“stranger”, “alien”, and “foreigner”) and morphe (“form”, “shape”).
There are no solid facts as to the origins of the Xenomorph species; instead, there are many assumptions which can not be confirmed. Based on the limited information we have, the most commonly accepted hypothesis is that they are an artificially created species, although another hypothesis says that they evolved naturally on a planet much different than our own.
The Xenomorph could be the result of genetic manipulation by Mala’kak (also known as the “Engineers” or “Space Jockeys”) as a terraforming mechanism about ten million years ago, but apparently it went horribly wrong. This theory has been twisted slightly by Prometheus, as they created an artificial subspecies, the “Deacon” or proto-alien.
Another theory is that they were actually the oldest and most technologically advanced of all races, but a sort of plague wiped out all the adults, leaving the offspring to devolve into a bestial state. The Mala’kak (Space Jockeys) may have been a close ally, possibly explaining why Xenomorph eggs were on their ships to LV-223 and LV-426.
Other ideas include that they were created by another race, perhaps the Yautja, as an “ultimate prey”. Xenomorphs are specifically said to not be indigenous to LV-426, a relatively small and unknown planet, where a large body of their eggs were found in the hold of a derelict Mala’kak/Space Jockey ship. No one knows if they were using the eggs for research or as a bio-weapon. Some say that billions of years ago, the advanced race (probably the “Space Jockeys”) controlled much of the universe with the Xenomorphs, but were wiped out by them.
Another theory touched on in the expanded universe is they were the alpha predator of their own ecosystem on a nightmarish and harsh planet, but were spread throughout the universe as a food source and a delicacy to a species with a natural immunity to their acidic blood. Without their native ecosystem to keep them in check they have since run rampant.
One idea though, is that they were created by the Mala’kak as biological weapons against an unknown threat or a weapon to wipe out humanity, and the eggs at the derelict ship found at LV-426 was in fact a biological weapon that turned against the crew. Ridley Scott states during the Director’s Commentary on the Alien Special Edition DVD that the eggs are the cargo of the Space Jockey’s ship with the ship being a sort-of war ship designed to carry these biological weapons, or perhaps a science vessel carrying the eggs as cargo for scientific study.
The Xenomorph physical form varies wildly depending on its life stage, hive caste, age and host, with numerous genetic varieties existing whose origins are completely unknown, as well as varieties which have been genetically engineered by other species. The typical Xenomorph starts life as an egg-like creature which, when detecting the presence of a potential host, opens up to release the second stage: a small quasi-arachnoid life form which launches itself onto the host’s face and impregnates it with an endoparasitoid larvae, which later consumes the host from within and exits the body as a vaguely worm-like organism, which then grows very quickly, developing into the adult Xenomorph.
Although several varieties exist, the adult Xenomorphs all tend to share some common traits: a vertebrate-like body, a protective exoskeleton, a long flexible tail, an elongated eyeless head, and a toothed maw which hides a retractable inner mouth. Little is known about their biology, but it is known that they eat with their “tongue mouths”, not their outer mouths. This mouth is somewhat similar to the pharyngeal jaw of a moray eel. They also bleed extremely acidic fluid which is yellowish green in color and often referred to as “blood”, although whether it’s used to transport nutrients through the body and/or serves other functions is not clear.
While the extremely acidic fluids and tremendous resilience displayed by the creature might suggest an alternative kind of biochemistry; the fact that the Xenomorph not only feeds on Humans but actually develops inside them strongly suggests that its biology is carbon-based. The ability to inherit traits from its hosts also suggests that it incorporates genetic material from them, implying that the Xenomorph either has DNA, or is able to read and convert DNA into whatever means it uses to store genetic information.