In the director's commentary for Aliens, James Cameron noted that the Xenomorphs in Aliens had been alive far longer than the Xenomorph in the original, and therefore had more time to learn how to manipulate basic-level machinery. Although they do not demonstrate Human and Yautja-level intelligence as a species (such as abstract reasoning, introspection and technological advancement), their queen appears to possess considerable acumen in its social behavior and manipulation of human technology, such as cutting the power of the LV-426 colony and operating an elevator. Xenomorphs appear to possess a roughly similar intelligence to that of a typical primate, but have shown to learn relatively quickly, utilizing the situation around their environment. 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. While the extremely corrosive fluids and tremendous resilience displayed by the creature might suggest an alternative kind of biochemistry, the fact that the Xenomorph not only feed on Humans, but actually develop inside them, strongly suggests that its biology is carbon-based. It is dull yellow in color and often referred to as "blood", although whether it's used to transport nutrients through the body and/or just serves simply as a defensive mechanism is not clear. They also bleed an unknown and extremely corrosive Fluoroantimonic acid type of fluid. This mouth is somewhat similar to the pharyngeal jaw of a moray eel. Little is known about their biology, but it is known that they eat with their inner or secondary mouths, not their outer mouths. This parasite then consumes the host from within and exits the body as a vaguely worm-like organism, before growing very quickly and developing into an adult Xenomorph.Īlthough numerous varieties exist, adult Xenomorphs all tend to share some common traits: a vertebrate-like body, a protective exoskeleton, a long flexible tail, an elongated domed head, with nearly invisible eyes near the mouth, and a toothed maw hiding a proboscis-like inner mouth. The typical Xenomorph start its life cycle 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 (Facehugger) which launches itself onto the hosts face and impregnates it with an endoparasitoid larva. The physical form of a Xenomorph can vary depending on its life stage, hive, caste, age, and host, as well as varieties which have been genetically engineered by host species or genetically grown. The Queen of this species is generally twice as large (although some Queens have shown to grow even larger, some surpassing 100 feet tall if given time) and possess superior speed, strength and intelligence than their offspring. The human phenotype is generally around 7–8 feet and roughly 136.0 to 181.4 kilograms in weight, with a long, muscular tail and large, curved, oblong head.
The appearance of the Xenomorph can vary depending on the host in which the Facehugger implants. One of the deadliest of all known alien species, these creatures require a host organism in order to reproduce.
The Xenomorph XX121, better known just as Xenomorph (which literally translates to "strange form" from Greek ξενος, xenos=strange and morphe=form) or the "Alien", is an extraterrestrial endoparasitoid species with multiple life cycles, possibly originating from the planet Proteus. Its structural perfection is matched only by its hostility." Xenomorph "You still don't understand what you're dealing with, do you? The perfect organism.