The Zoo Theory attempts to explain one of the most enduring mysteries of our time: why, if intelligent extraterrestrials are out there, haven’t they gotten in touch with us yet.
Are aliens watching us from afar?
Making contact with aliens, both hostile and friendly, has captured the imaginations of writers and filmmakers for decades. Still, in spite of all the creative ways we’ve envisioned what life with aliens would be like, we haven’t actually made contact with said aliens yet. Given how large the universe is and how many planets out there are potentially able to host life, it seems somewhat unreasonable that we’re the only living things in this entire cosmic expanse.
There are a lot of theories that intend to explain why we haven’t made contact with extraterrestrial intelligence (ETI) yet, in spite of the huge possibility that they’re out there somewhere. One such theory is the Zoo Theory, which subverts many other possible explanations as to why we still feel alone in the universe.
How much more advanced than us could these aliens be?
"Why are we unaware of ETI?” astronomer John A. Ball asks in this paper. “A premise of most searches is that ETI are trying to communicate with us, but we are not quite clever enough to see or hear them. I suggest, instead, that if ETI had chosen to announce their presence to us, we would be aware. Since we are not, I presume they have not.”
Ball thinks that ETI is not only out there, but they’re also smarter than us. They observe us from afar, much like the way biologists observe various organisms and take utmost care not to interfere with their subjects. Ball also thinks that the time scale between aliens and humans is more like that between humans and molluscs, and less like that between technologically advanced civilizations and more primitive ones.
Ball’s theory touches upon efforts to find and make contact with ETI. There are a number of plans to explore planets or moons in our solar system that may possibly host life, but Ball thinks that efforts to find advanced alien life are ultimately futile. He compares these efforts to looking for birds in empty eggshells, because planets that can support life are likely not where ETI resides, but rather where they originated.
Which of these theories will eventually be proven to be true?
In spite of what Ball thinks, however, plans to explore Mars and moons like Enceladus and Europa for signs of life seem to be rolling along. Other theories on ETI say that yes, it’s likely that aliens are out there, but they may be unable to make contact with livings on other planets. Scientists think that it’s highly possible that these planets or moons support microbial life, not highly intelligent life forms that basically make us seem like bivalves at the bottom of the ocean. It’s more likely, these scientists say, that we’ll encounter microbial alien life than highly complex alien life.
There is also a theory that complex extraterrestrials may be out there, but they’re stuck in waters covered by thick layers of ice. This ice layer is possibly keeping intelligent life from breaching to the surface and making contact with life forms on other planets.
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