A civilization, I think, is like a shark. You know? It has to constantly move forward or it dies. And I think what we got on our hands is a dead shark. -- (with apologies to) Woody Allen
Rather than ponder the fate of our Nation, which will start to shift direction on Tuesday and is a rather minor issue in the grand scheme of things, I thought it would be useful to zoom out and take a longer view, According to the LA Times, there may be billions of earth sized planets located in the habitable zone (where liquid water can exist) orbiting their suns: [HT: Steve Sailer]
Many Earth-like planets orbit sun-like stars
At least one in every four stars like the sun has planets about the size of Earth circling in very close orbits, according to the first direct measurement of the incidence of such planets, researchers said Thursday.
That means that our galaxy alone, with its roughly 200 billion sun-like stars, has at least 46 billion Earth-size planets orbiting close to the stars, and perhaps billions more circling farther out in what scientists call the habitable zone, said astronomer Andrew Howard of UC Berkeley, a coauthor of a paper on the subject published in Friday's edition of the journal Science.
So, as Enrico Fermi asked, where is everybody?
One fashionable answer is the existence of a Great Filter:
The Great Filter, in the context of the Fermi paradox, is whatever prevents "dead matter" from giving rise, in time, to "expanding lasting life".[1] The concept originates in Robin Hanson's argument that the failure to find any extraterrestrial civilizations in the observable universe implies the possibility something is wrong with one or more of the arguments from various scientific disciplines that the appearance of advanced intelligent life is probable; this observation is conceptualized in terms of a "Great Filter" which acts to reduce the great number of sites where intelligent extraterrestrial life might arise to the tiny number of intelligent species actually observed (currently just one: human).[2] This probability threshold, which could lie behind us or in front of us, might work as a barrier to the evolution of intelligent life, or as a high probability of self-destruction.[1][3] The main counter-intuitive conclusion of this observation is that the easier it was for life to evolve to our stage, the bleaker our future chances probably are.
Since the human mind naturally enjoys Apocalyptic fantasies (which is why our news media know that if they want to stay in business they had better stick to their simple rubric--"If it bleeds, it leads") the tendency has been to think of the Great Filter as some self imposed calamity, a nuclear war or biological warfare that gets out of control, or some other man caused disaster. This approach suggests that life, even intelligent and technological life, may well be ubiquitous but at some point in any civilization's development events occur which destroy the civilization. There is a kind of perverse comfort in the belief that we are powerful enough to destroy our planet and ourselves; the current iteration of this belief is embodied in the Global Warming alarmists, but in every generation there is an equivalent belief in an impending end times.
Recently, another candidate has emerged, a theory which suggests that the step from uni-cellular life to multi-cellular life is so complex and so difficult that it may well have happened only a very limited number of times; perhaps we are truly a one-off event:
Why complex life probably evolved only once
The universe may be teeming with simple cells like bacteria, but more complex life – including intelligent life – is probably very rare. That is the conclusion of a radical rethink of what it took for complex life to evolve here on Earth.
It suggests that complex alien life-forms could only evolve if an event that happened just once in Earth's history was repeated somewhere else.
All animals, plants and fungi evolved from one ancestor, the first ever complex, or "eukaryotic", cell. This common ancestor had itself evolved from simple bacteria, but it has long been a mystery why this seems to have happened only once: bacteria, after all, have been around for billions of years.
The answer, say Nick Lane of University College London and Bill Martin of the University of Dusseldorf in Germany, is that whenever simple cells start to become more complex, they run into problems generating enough energy.
In order to gather as much energy from the environment to meet the demands of complex multi-cellular organisms, an extremely unlikely event had to take place, one simple cell had to engulf another, the unicellular organism that persists as our mitochondria, the energy factories of our cells.
Once freed from energy restraints, genomes could expand dramatically and cells capable of complex functions – such as communicating with each other and having specialised jobs – could evolve. Complex life was born.
So if Lane and Martin are right, the textbook idea that complex cells evolved first and only later gained mitochondria is completely wrong: cells could not become complex until they acquired mitochondria.
Simple cells hardly ever engulf other cells, however – and therein lies the catch. Acquiring mitochondria, it seems, was a one-off event. This leads Lane and Martin to their most striking conclusion: simple cells on other planets might thrive for aeons without complex life ever arising. Or, as Lane puts it: "The underlying principles are universal. Even aliens need mitochondria."
Of course there is no reason the initial Great Filter precludes the existence of other filters that come into play at later points in the process of evolution of life from single celled creatures to technological civilizations.
I would add another possible candidate for a Great Filter. A civilization is indeed like Woody Allen's shark. We have already reached the point where a failure of technological progress would be likely to doom us to another Dark Age, where life devolves into a zero-sum, Hobbesian existence. This would represent a massive failure of imagination and courage as the most frightened and regressive elements on the planet gain primacy. In the name of saving the world from Anthropogenic Global Warming, or in thrall to a blood thirsty Allah, and with the failure of the Last, Best Hope of Man, we will surrender the future for an imagined, Utopian past. Perhaps the last Great Filter will simply be the bureaucracy that uses its rules to make innovation so difficult that progress grinds to a halt. We would be left with the poet's epitaph:
This is the way the world ends
This is the way the world ends
This is the way the world ends
Not with a bang but a whimper.
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