If one wants to take a daring gander into the extended universe of “Alien,” one will find that Marvel Comics began a new title based on “Alien” in 2021. In the sixth issue of that series, an android pointed out that the xenomorphs were made for a different purpose than divine revenge. An android refers to the animals as “Prometheus’ cleansing fire,” implying that the aliens are used regularly to wipe out great swaths of living beings. The xenomorphs are used to keep any and all sentient creature populations at bay.
Why are there so many living extermination tools? While the comic book does not answer that question, it does explain a great mystery about the galaxy summed up by the Drake Equation and the Fermi Paradox. The equation, named by Dr. Frank Drake in 1961, is a means to calculate the probability of other intelligent species in the galaxy. Given the sheer number of stars, it seems probable that human-like life would inhabit other worlds. The Fermi Paradox, however, posits that if life can so easily evolve on other worlds, it stands to reason that at least one alien species would have invented interstellar travel by now and come to visit us. Indeed, it’s illogical that they haven’t.
If, however, there is a species of genetically engineered monsters in the mix — and one that was bred specially to wipe out other species — then it would explain why no one alien species ever meets another. As soon as one species takes to the stars, xenomorphs appear to kill them all. Then, once sated, the xenomorphs return to a dormant state in eggs until the next time around.
With xenomorphs in the mix, the Fermi paradox is solved!