The Invasion Theory - Early in the UFO years (say after the Arnold/Mr. Rainier sighting in 1947), abductees and contactees claimed the aliens were setting the stage for a massive invasion. It's an attractive theory and one that has been popularized in films, stories, and radio plays (War of the Worlds, Mars Attacks, Starship Troopers, et al). The invasion theory has one fundamental flaw: a civilization that navigates space, and even time, could easily overrun a planet that first took to the skies 103 years ago at
Kitty Hawk. If the invasion theory is correct, well, then, it's likely the invasion is already over. Supporters of the invasion theory have begun using the Genetic theory to explain why have not yet been invaded. The aliens, they say, cannot exist here without genetic modification, which has lead to the abductions, mutilations and breeding/hybrid experiments.
The Greys Are Just Intergalactic Sightseers - The aliens arrive here for the same reasons we visit the Galapagos Island, Mexico, or Antartica, climb K2 or Broad Peak, or walk on the moon. The visitors are curious; they find the animals, and plants and, most of all, the antics of the homo sapiens interesting. We are a roadside attraction on the great stellar highway.
Judging from the variety of spaceships reportedly seen by observers, the visitors may hail from several other planets, or from various "countries" on one planet. Perhaps they told each other via some great galactic internet about the bizarre goings on on Earth.
The Greys Visit Because We Have Something They Desperately Need - This theory attempts to account for the reported abductions, cattle mutilations, genital inspections, implants, alleged inseminations, crop circles, and other unexplained, or unexplainable, phenomena. The crop circles could just be interstellar graffiti. The theory on the UFO community is that we're being visited by several races--some benign, some malignant--and they all have an agenda.
Some people posit that the aliens are here to mine organic material in short supply on their planet. The cattle mutilitations are often attributed to the greys lacking some essential fluid or nutrient--and they are forced to sweep the galaxy looking for new supplies.
Another popular theory has the Earth may containing minerals absent from the alien planet. This is partly the basis for the claims of vast underground colonies of aliens (
such as the Dulce base). There have also been reports of UFOs and aliens taking samples and cores of our flora and fauna (up to and including ourselves!).
Some UFOlogists have pointed out that extensive mining operations would be easily noticed--for example, if the Aliens were carting away many tons of bauxite omagnesiumum. . .we might notice eventually. Other researchers point out that they may need only small samples to clone or duplicate in their obviously far advanced laboratories.
The Day The Earth Stood Still Theory - One theme that comes back again and again (both from observation, and from tales of abductees) is that the visitors are here to help us mend our evil ways. We may just be an outpost of a civilization that seeded us millenniums ago. They come back to check up on their colony. Remember Klaatu from
The Day The Earth Stood Still? He came to warn us of the consequences of our bellicose society. Some abductees claim to have seen images--mental film loops--of the Earth's annihilation through neglect and war. "Contactees" of the 1950's claim to have been shown similar mental 'films' about the consequences of neglecting peace and the earth itself.
One researcher points out that these claims surfaced shortly after the first atomic bombs had been detonated in the 1940s. And many of the most famous sightings have occurred near nuclear installations, (Roswell was the world's first nuclear bomber Air Force Base).
Alien Sex/Genetic Manipulation? - Abduction victims claim that they were subjected to strange experiments including the removal of semen from men and eggs from women. Some women claim that they have been impregnated only to have the fetus removed shortly after conception. Why? One popular theory says that an alien civilization needs to crossbreed with humans to forge a new, stronger of hybrid aliens. Numerous abductees speak of seeing 'human-like' children on board alien craft.
Another theory claims the aliens are cross-breeding in order to live on earth. Their native bodies could not survive on earth due to atmosphere differences and our diseases. . .without some adaptive genetics. (see above, "the invasion theory").
---o0o---
