I'm wanting to know how the timeline works in the Alien/Predator universe, specifically in relation to the Xenomorph's evolution.

As far as I know the Xenomorph starts its evolution from the end of Prometheus, as an early version of what looks like the Xenomorph appears out of the dead engineer. I assume it then evolves from this into what we see in the original Alien 30 years later.

What I want to know is how this ties in with Alien Vs Predator? As far as I remember, and based on the timeline I've found, the Predators are hunting Xenomorphs on Earth as early as 2896 BC. Alien Vs Predator also seems to be set in 2004 AD. While Prometheus is set in the late 21st century.

What I want to know is if I've got it wrong. I thought it seemed like the Xenomorph was in its first evolution at the end of Prometheus, but is that an alternate species and the Xenomorph was already created 5000+ years before that?

Are there any books/comics/games/movies that help explain this?

If that is the case, and the Xenomorphs have been around thousands of years, it seems strange to me that the Xenomorph in Prometheus looks so similar to the Xenomorphs of the Alien movies (given how quickly they evolve).

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    My personal explanation is that the Aliens Vs. Predator movie is not canon.
    – CamelBlues
    Jul 30, 2012 at 1:35
  • @CamelBlues personally Id much rather think that Prometheus and its sequel wasnt canon…
    – Moo
    Nov 21, 2021 at 1:56

13 Answers 13


No timeline could properly chart the Xenomorph's changes because we have never seen the original creature in its native environment! Even changes in the creature over the course of the series only reflect the creature as it has taken on new genetic materials wherever it is.

We know the Predators have been bringing them to Earth since before recorded history. Building pyramids at the South pole is a good clue of how long ago this had to have been. We know that the Engineers have had them for at least 2,000 years. But we have no idea of the relationships between the sources of the two creatures and how much evolution has occurred between their different source Xenomorphs.

I don't see the Xenomorph's rapid genetic changes as evolution. I see this as a form of rapid genetic mutation/manipulation where the creature is adapting/mutating depending on the wildlife from which they swap genes with in order to spawn in the local environment.

With such a mutable genetic structure, it would be difficult to determine purely from an appearance point of view, what creature started off as the parent species, or if we have ever seen a genetically pure one.

It would require a genetic scan from a creature that has never left its first home environment to differentiate which form was the original and which features were from the native planet. As I have stated in previous StackExchange conversations on the Xenomorph:

The most damning evidence as a sign of their engineered heritage is their uncanny ability to gestate from a variety of host organisms and the speed of their growth. They do not need to take more than a day or two to reach full adulthood. They are born knowing how to hunt, track and prepare their prey for implantation. We know for certain that they can develop in humans and the Predator species. We have also seen them gestate in dogs, creating functional if not attractive xenomorphs. Taking human and Predator DNA into account, that is three completely different species who are genetically compatible enough to produce viable offspring. In genetic terms, this would be highly unlikely, on the order of nearly impossible without an advanced technology making it possible. --Scifi.StackExchange > What purpose is acidic blood to a Xenomorph?

I believe in their native environment, wherever that is, they are all very similar or have a default genetic structure they attempt to return to if the conditions allow it. As a variety of aliens come to their world and use them in other environments, the new spawn may resemble less of their original genetic heritage but the potential for the original genes may always be there. Indeed, the creatures may possess the ability to reset their genetic structure as they adapt to a new environment and return to their previous physical shape, keeping the genes necessary for survival and only the external changes necessary for the environment.

Since we have also seen the Xenomorph take the characteristics of the creatures it hosts within (taking on the Predator characteristics for example in AVP and AVP: Requium) this implies an intelligence behind the design of the creature to build an organism able to gestate in a variety of organisms of different genetic structures, from different planets and to produce viable offspring of sufficient strength, speed, coordination, and intelligence to work cooperatively, telepathically (assuming a queen is available), or using a very fast other means of interacting that seems like telepathy and be able to quickly take over an area as effectively as these creatures do.

Dark Horse gives us a look at the creatures on a planet where there are two warring factions of the Xenomorphs, Aliens: Genocide, 1997, but one faction is red, the other classic black. We are not told if this is the homeworld or just another world long conquered by the species. All we can be sure of is they are not good at sharing a planet. Both groups tend to resemble what is considered the classic form of the creatures, as we have come to know them.

Aliens: Genocide, Dark Horse Comics, 1997

Aliens: Genocide, Dark Horse Comics, 1997

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    1. Recognise after first sentence this is a Thaddeus answer, 2. Upvote accordingly, 3. Finish reading high quality answer.
    – AncientSwordRage
    Jul 1, 2013 at 7:25

Given that in Prometheus, there is a carving/relief of a xenomorph-like creature on the wall (shown below), the two thousand year old AvP backstory is more viable than not. The relief means that the xenomorph had existed far before the events in Prometheus, and that means there is the possibility that the Predators acquired the genetic ooze, or a reproductive host. In fact, in AvP, the Predators detained and used a Queen (the kind seen in Aliens) to lay eggs and reproduce in the pyramid maze. How the Predators acquired the Queen can be left to speculation, but the point of the matter is, the AvP backstory is viable. xenomorph carving/relief on Engineer ship's inner wall


Prometheus was meant to erase AVP from Alien Canon, also the Engineers were on earth before the Predators arrived. The Deacon was probably reusing the same essence that created the original xenomorphs millions of years ago. So there's no predator-space jockey war, no Charles Bishop Weyland, no Antarctica expedition, and no predators building pyramids on earth because the engineers were on the planet thousands of years before then.

Weyland Corporation was founded by Peter Weyland not Charles Bishop Weyland because you can't establish/found the same corporation twice and their dates on both timelines are off.

Info on the Alien Timeline


There are a few things to consider:

  1. REDUNDANT ARGUMENT theory: The AvP world isn't considered Alien 'canon' in which case the writers/director totally didn't care about any inconsistency in timeline. The following is an excerpt from Wikipedia referencing R. Scott -

    Conversely, Ridley Scott had no interest in the Alien vs. Predator films. When asked in May 2012 if he had watched them, Scott laughed, "No. I couldn't do that. I couldn't quite take that step." ref: Ridley Scott Interview -- Prometheus (youtube)

  2. ENGINEERS theory: For arguments sake though, lets suppose it IS cannon, then the alternative could be that, as mentioned by other posters here, that the ENGINEERS created the gene code but at a much earlier timeline, the Predators got hold of it and planted the Xenomorphs on earth as per the events of AvP. If any theory is going to bridge the apparent inconsistency, then this is a strong runner.

  3. PREDATORS theory: this is an unlikely theory but it could be that the PREDATORS have created the xenomorphs and the Engineers merely grabbed the gene templates and were recreating them for warfare themselves. This is a possibility but is unlikely because nothing in their own cannon so far indicates that the PREDATORS the gene dabbling type. They seem more tribal minded if supremely advanced in technology.

  4. Random Other theories: The ENGINEERS created the xenomorphs as we know them BUT the XENOMORPHS contain some kind of MASTER DNA. They after all, mutate with other living creatures like humans, engineers, predators and, er.. dogs. So the ENGINEERS, on some kind of quest for their own origins identified the master DNA which initially spawned the variety of life in the universe. This is a pretty far flung and small needle in a universe-sized haystack but hey, that's sci-fi! lol there is one indication that may support that something like this isn't totally impossible; the following is an excerpt from Damon Lindelof (Writer of Prometheus)

During the creative process of Prometheus, all involved (that includes Fox and Ridley) had a strong desire for this film to launch off in its own way so that by the end, it would not connect directly to the original ALIEN, but instead run parallel to it. This is something that I talked about many, many times in the press burst around the release of the movie. As you probably remember, there was a lot of interest as to whether Prometheus was a "prequel" - the answer was, "Yes. Sort of. But if there was a sequel to Prometheus, it would not be ALIEN."

So this may make Prometheus the non-Alien-canon or may eventually catch up via the random theory I mentioned in point 3.

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    In addition to the comment by Ridley Scott, doesn't the fact that the Prometheus movie presents Peter Weyland as the founder of the Weyland corporation, while AvP had its own distinct head of Weyland in modern times named Charles Bishop Weyland, pretty much rule out them taking place in a common fictional universe?
    – Hypnosifl
    Oct 25, 2014 at 19:05

Based on the Dark Horse Comics and some of the novels set between Aliens and Alien 3, it seems that the Engineers created and/or engineered life on many worlds using their own DNA as a starting point.

It seems that the stuff used to engineer DNA became unstable, and started to create its unexpected lifeforms (as seen in the film) - this is my take on the running holo vid of the Engineers evacuating the base when it goes wrong.

The engineers had mistakenly create the aliens and had tried to set a plan to wipe them out in place (star maps in the bridge of the alien ship) - in one novel Ripley meets one of the Engineers who telepathically conveys his hatred of all other life but mostly the hatred and need to destroy the Aliens first so he leaves her for later.

So the timeline as I see it is ok.

  1. Engineers create all life
  2. Experiment goes wrong which makes the Alien
  3. Predators find the Aliens and hunt them
  4. The Predators bring some to earth to hunt them here
  5. Ripley encounters another Alien on a different planet
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    A reasonable answer - but fairly questionable in terms of canon since it relies on comics and novels outside of the movies (mind you, there is some question about using AvP to bridge the two movie franchises)
    – HorusKol
    Jul 29, 2013 at 0:49

The Prometheus film takes place on a planet covered with bio-weapons. There is no evidence the Xenomorph has any natural relative and could have been made completely from scrap by the Engineers. The ship in Alien has a body in a chair that looks like an Engineer. From this, it looks like the Xenomorph got lose and destroyed most, if not all, of the Engineer civilization. From a ship similar to this, the Predators could have gained their initial seed stock of Xenomorphs (Engineers may be extinct by this point). It does seem that Xenomorphs have a basic genetic code which is not affected by the host and then they take additional code from their hosts. I do not know if the classic Xenomorph is from several generations of breeding through Engineers. The Xenomorph in Prometheus is simply one of the original specimens that got released and began reproducing. The fact it used an Engineer as a host is probably why it looks so similar to classic Aliens and is causing most confusion.


I think the Predators and Engineers were enemies so the engineers retaliated against the Hish or Yautja or whatever you call the Predators; first by creating humanity, then when humans seemed ineffective, they decided to wipe predators and humans out using a new weapon that could kill, kill, and kill some more, all the while breeding and breeding like nobody's business, instead of wiping out humanity or the Predators, it backfired, wiping out the Engineers as for whether they evolved naturally I think they did, with some help from the Engineers, hence the wicked modifications caused by different hosts.


If the Engineers' Black Goo + humans = Aliens (as we know them from the films), then all Predators would need to create Aliens to hunt is some human hosts. From AvP, it looks like Predators did not have any trouble convincing humans to hand over a small group of hosts as often as they needed them. Thus, it's possible that Aliens (again, in the form we know them) can have multiple "origins," one being some Aliens that Predators bred via humans thousands of years ago, and another origin point being the Prometheus' encounter with the Black Goo on the Engineers' planet.


Could it be the the engineers were simply the first species ever to exist, then they created humans and the rest of life on earth as an experiment to show the parameters of their power. Then after a while (billions of years) the engineers saw that the humans where the superior species and with the help of the engineers assisting human evolution, the humans became smart, even too smart. The engineers then fealt scared of the human's power. The engineers then wanted to eradicate us, so they created two species of alien, the black and the red, planted them on a planet and where waiting to see which species of alien would be dominant (black) so they can plant it on earth to eradicate us. The plan obviously failed as the whole planet became a wasteland killing all the surveying engineers bar one (the one we see in Prometheus). The engineers needed a force smarter and more elusive than the engineers and created the predators as a result. For a time the predators may have been loyal to the engineers, but soon realized that they wanted to have their own agenda, thus taking the alien remnants from the planet from Prometheus and taking them to earth. The humans, expecting the engineers to teach them, found the predators instead, who offered knowledge in exchange for human sacrifice, the humans obliged. In the original Prometheus script it describes the engineer's residences as pyramids, the predators, once living as a slave force and army for the engineers, now knew how to build them, and taught the humans. At this point the engineers have fallen on their own sword because they created three superior species (humans, aliens and predators) who then caused they're decline, this is why the engineer from Prometheus is so angry at the humans. This is just a theory though.


Actually, in the "Extended Universe", the history with the Aliens goes way more back than thousands of years.

In The comic Aliens: Apocalypse, it is said that circa 3.2 billion B.C the Space Jockeys control most of the galaxy, including Earth. About 1.6 billion B.C they are almost wiped out by an Alien outbreak. Only a few of the Space Jockeys survive. The comic also includes a "Space Jockey Alien", who is huge. This is one of several of Earths "secret" history with the Aliens and Space Jockeys, you can see the other ones here: https://www.avpcentral.com/earth-infestaton


Ok, as far as I know, the xenomorphs are nothing more then a bio-weapon made by the engineers and used for hunting by the predators so it means the predators and engineers had a truce or understanding. If the predatos got the serpents the engineers got weapons and ships.


Just a guess but I think the Alien creature is just a part of a genetic weapon that will create genocide on multiple planets. I think earth is a warning or a burn and destroy or destroy all the food bridges etc. for enimies of the engineers. It seems at the beginning of Promethesus the Genetic weapon is activated as a chemical spill on the planet LV 23 by an Anti-Genocide Activist since this weapon causes complete destruction of all life on the planet or planets. These activists that destroy this secret weapons facility get the weapon used on them and become the Predator race which they are able to stop the Genetic weapon before it destroys them. The engineers try to destroy the planet earth 2 times first they are saved by the activists which Shaw may know or not know about, that is the beginning of Promethus with the Genetic chemical spill. The second time Shaw may know about also since it is recently and that is during the Mayans time where the Alien weapon is stopped but only halted by the Preditors. The Weapon protects itself by saving a queen and the eggs or pods which can withstand time and extreme weather conditions and the Preditors are watching to see if the infection had been completely stopped. Which it hadn't that is AVP at the South Poll and AVP Reliquim. This all orginated in the 60's from stagnant germs that grow in cars on long trips and while space travel may take life times the mutation of these germs may develop these ways LOL.

  • 1
    Welcome to the SFF.SE. Just so you know, adding speculation as an answer to a question that already has an accepted answer is discouraged. You can checkout the tour to get an overview of how the site works and visit the help center for more information.
    – numaroth
    Oct 24, 2014 at 21:48

I like the suggestion that the xenomorphs go back to some sort of master DNA for all life and that the Engineers discovered it, with disastrous consequences. This is a great idea to take into Prometheus sequels because it relates to the bigger picture of life - why it exists, what is its purpose, where did it all come from. It adds more intrigue and more dark mystery to the storyline

  • I think this answer is more of a comment than an answer. Or maybe you could explain a little bit more ?
    – Kalissar
    May 24, 2013 at 8:56

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