A Darwinian explanation for the Fermi paradox [UPDATED 4/21/2011]

April 18, 2011 by Amara D. Angelica

Arecibo Observatory: did the "Arecibo Message" transmitted toward the Andromeda Galaxy in 1974 risk extinction of our species? (Credit: NAIC - Arecibo Observatory, a facility of the NSF)

The Fermi paradox is the apparent contradiction between high estimates of the probability of the existence of extraterrestrial civilizations and the lack of evidence for, or contact with, such civilizations. As Enrico Fermi asked, “Where is everybody?”

One answer is that extraterrestial life sufficiently advanced to be capable of interstellar travel or communication must be rare, since otherwise we would have seen evidence of it by now. This in turn is sometimes taken as indirect evidence for the improbability of life evolving at all in our universe.

In an April 4 paper in arXiv, Adrian Kent of the University of Cambridge and Perimeter Institute suggested two alternate reasons why we haven’t heard from extraterrestrials:

  • “Intelligent species might reasonably worry about the possible dangers of self-advertisement and hence incline towards discretion” — the “Undetectability Conjecture,” suggested by Beatriz Gato-Rivera in http://arxiv.org/abs/physics/0308078 and arXiv:physics/0512062v3.
  • Strengthening that argument: “Evolutionary selection, acting on a cosmic scale, tends to extinguish species which conspicuously advertise themselves and their habitats.”

Transmitting to ET: bad idea?

Kent concludes with an observation: “It often seems to be implicitly assumed, and sometimes is explicitly argued, that colonising or otherwise exploiting the resources of other planets and other solar systems will solve our problems when the Earth’s resources can no longer sustain our consumption. It might perhaps be worth contemplating more seriously the possibility that there may be limits to the territory we can safely colonise and to the resources we can safely exploit, and to consider whether and how it might be possible to evolve towards a way of living that can be sustained (almost) indefinitely on the resources of (say) our solar system alone.”

In SHOUTING AT THE COSMOS … Or How SETI has Taken a Worrisome Turn Into Dangerous Territory, astrophysicist and science-fiction author Dr. David Brin advises that “people who care about [transmissions from Earth] — preferring a wide-ranging discussion before a few individuals start screaming into space on our behalf — are going to have to do some yelling of their own.” He explores this issue further in A CONTRARIAN PERSPECTIVE ON ALTRUISM: THE DANGERS OF FIRST CONTACT and other thought-provoking articles.

Response from David Brin [added 4/21/2011]

In fact, I’ve been wrassling with the Fermi Paradox since before it was called that. Since 1985, when I named the mystery “The Great Silence” — in what is still the only full review article ever on the subject.*

In that paper, I catalogued almost a hundred explanations that people have offered for the silence in the sky and our appearance of being the only civilization around. Alas, this topic brings out the most impulsive and opinionated side of many people. Folks tend to choose one particular answer, over all the other possibilities, for reasons having a lot more to do with individual psychology than either logic or evidence.

If you look at the good old Drake Equation (it needs to be expanded by a couple of factors), then it’s clear that some factor must be lower-than-expected, in order to make the emptiness we seem to see around us. But which factor?

Funny thing.  Those who *want* the cosmos to be empty of competition (so we can fill it) tend to choose Drake factors on the left side.  Those who are eager for contact tend to choose factors on the right side!  Moreover, once a person picks a favorite explanation, he or she tends to cling to it, vociferously sure that all other theories are nonsense.  I’ve seen this happen to some of the smartest guys I know.

Almost nobody seems willing to admit “We just don’t know; there’s too little data.”

The particular “Darwinian” theory recently published amounts to “they’re all cowards because some predatory types out there may be mean and so everybody’s hiding.”  Alas, it is an old, old, old hypothesis.  It’s been around a boringly long time. Moreover, I find it a bit sad that the authors actually think they invented it.  Heck that explanation could be true… and I am hoping we’ll have a moratorium on idiotic “message” shouting till we learn a bit more.  But that doesn’t make the idea original.

Someday, I hope, people will enter this fascinating field actually interested in exploring the full scope of ideas that it allows, before blabbing “I just figured it out!” the first moment they get a notion. Perhaps one day when curiosity outweighs egotism.  Heck, maybe then we’ll be ready for contact! ;-)

- David Brin

My “Great Silence” paper about the mysterious Fermi Paradox, the strange lack of signs, in the heavens, of extraterrestrial intelligent life. Quarterly Journal of  Royal Astronomical Society, Fall 1983, v.24, pp283-309 (downloadable at http://www.davidbrin.com/sciencearticles. http://adsabs.harvard.edu/abs/1983QJRAS..24..283B)