How special are we? A recent research paper suggests that terrestrial-style biology may be rare, and Earth may be among the first examples of a planet able to sustain life in the cosmos.
Even as the new kids on the block, humans are seemingly one of the precious few instances of intelligence to arise in the universe since the Big Bang did its thing.
Harvard Astronomer Avi Loeb and his colleagues in the U.K. have argued that the halcyon days for life are still to come. It’s not even morning in the universe; it’s pre-dawn. Biology may erupt like weeds on an untold number of worlds, but if so, the infestation will take place tens of billions of years in the future.
Why’s that? And what’s wrong with life sprouting up today?
Obviously nothing. After all, you’re reading this — you, the distant descendant of a small collection of molecules that stumbled on a method for building nearly exact replicas of itself nearly four billion years ago. No scientist is yet sure if this molecular sleight-of-hand is just some sort of highly unlikely event, although opinions abound.
The new argument that primetime for an inhabited universe is still to come springs from astronomy, not biology. Loeb et al.’s proposition begins with the belief that life requires a few essential ingredients: a world that’s amenable to easy chemistry, including liquid water, thick atmosphere — you know the drill. As best we can tell, there’s no shortage of such Goldilocks orbs — there may be tens of billions of Earth-like planets in our galaxy, and that’s not even counting habitable moons.
An abundance of real estate is essential for this growth, yes. But so is time. Rustling up life, especially of the intelligent variety, might take billions of years.
The argument is straightforward: The longer you wait, the more examples of biology you’ll have. But stars like our Sun can’t wait too long: there’s a relatively short opportunity to strut and fret. In 10 billion years, they’ve run through their easily accessible fuel, and are headed out the door.
And here’s an additional fillip: Red dwarfs are as plentiful as bad drivers, comprising three-fourths of all stars. So not only are they individually a thousand times more likely to become winners in the biology lottery, there are a lot more of them buying tickets.
Loeb argues that, looking back on creation ten trillion years from now when the curtain is falling on the universe-as-we-know-it, you’d have to say that the overwhelming majority of life arose around red dwarf stars – and on average, trillions of years after Earth was over and done. So among inhabited planets it sounds as if Earth beat the rush. From the standpoint of future cosmic civilizations, we are the ancient aliens.
But is that so remarkable? Maybe not. Consider being a citizen of Rome during its Empire. There were about 200 million people in the world then. If you were particularly insightful, it might occur to you that the future human population could be much greater — indeed, there’s now 35 times as many people as strolled the world at the time of Jesus.
So that would make Romans special, right? There was a far greater probability that they’d be born after the Renaissance then in the time of the Caesars.
However, while interesting, that’s not to say the Romans were by any means the first humans or even the first to be somewhat civilized. There were 10,000 generations of Homo sapiens before them, and neither they nor the Romans would appreciate being dismissed by the claim that “the best was yet to come.” The galactic hordes may still be ahead, but that’s little reason to wait before trying to find some cosmic company. Are you willing to wait 500 billion years before learning whether anyone’s out there? That’s more patience than I have.
Seth Shostak is the Senior Astronomer at the SETI Institute, in Mountain View, California. He writes frequently on astronomy and other topics, and hosts the SETI Institute’s weekly radio show, “Big Picture Science.”
But consider red dwarf stars, the runts of the universe. Their masses are considerably less than Sol’s, which means they burn more slowly. The consequence? Red dwarfs with one-tenth the mass of the Sun have lifespans that are up to a thousand times longer.
All else being equal, that would give red dwarfs a thousand times the probability of eventually using its energy to host a world with life. Clearly, it’s most probable that this life would arise not when these stars are still young — which they all are now — but instead during their long adulthood. In other words, the red dwarfs are just getting started, and their biologically fecund years are still ahead.
This paper speculates on questions intending to be taken scientifically rather than metaphysically: “Can the human gut (enteric nervous system) be conscious?”; “Can your immune system think?”; “Could consciousness be coded in DNA?”; “What do we mean when asserting that an Extraterrestrial is Thinking, or is Conscious? We explore through reference to theory, experiment, and computational models by Christof Koch (Caltech), Barbara Wold (Caltech), and Stuart Kauffman (University of Calgary, Tampere University of Technology, Santa Fe Institute). We use a tentative new definition of thinking, designed to be applicable for humans, cetecea, corvids, artificial intelligences, and extraterrestrial intelligences of any substrate (i.e. Life as We Do Not Know It): “Thinking is the occurrence, transformation, and storage in a mind or brain (or simulation thereof) of information-bearing structures (representations) of one kind or another, such as thoughts, concept, percepts, ideas, impressions, notions, rules, schemas, images, phantasms, or subpersonal representations.” We use the framework for Consciousness developed by Francis Crick and Christof Koch. We try to describe scientific goals, but discuss Philosophy sufficient to avoid naïve philosophical category errors (thus are careful not to conflate thought, consciousness, and language) Penrose, Hameroff, and Kauffman speculate (differently) that CNS consciousness is a macroscopic quantum phenomenon. Might intestinal, immune system, or genetic regulatory network dynamics exhibit emergent cooperative quantum effects? The speculations are in the context of Evolution by Natural Selection, presumed to operate throughout the Cosmos, and recent work in the foundations of Computational Biology and Quantum Mechanics.
Anyhow, Humans are strange. For a global species, we’re not particularly genetically diverse, thanks in part to how our ancient roaming explorations caused “founder effects” and “bottleneck events” that restricted our ancestral gene pool. We also have a truly outsize impact on the planetary environment without much in the way of natural attrition to trim our influence (at least not yet).
But the strangest thing of all is how we generate, exploit and propagate information that is not encoded in our heritable genetic material yet travels with us through time and space. Not only is much of that information represented purely symbolically—in alphabets, languages, binary codes—it also is represented in each brick, alloy, machine and structure we build from the materials around us. Even the symbolic stuff is instantiated in some material form or other, whether as ink on pages or electrical charges in nanoscale pieces of silicon.
Altogether, this “dataome” has become an integral part of our existence. In fact, it may have been an integral, and essential, part of our existence since our species of hominins became more and more distinct some 200,000 years ago. This idea, which I also pursue in my book The Ascent of Information, leads to a number of quite startling and provocative proposals.
To begin with, we can look at our species’ energy use and see that of the roughly six to seven terawatts of average global electricity production, about 3 to 4 percent is gobbled up by our digital electronics, in computing, storing and moving information. That might not sound too bad—except the growth trend of our digitized informational world is such that it requires approximately 40 percent more power every year. Even allowing for improvements in computational efficiency and power generation, this points to a world in some 20 years where all of the energy we now generate in electricity will be consumed by digital information alone.
The energy tsunami of the human dataome doesn’t end there. We still print onto paper, and the energy cost of a single page is the equivalent of burning five grams of high-quality coal. Devices, from microprocessors to hard drives, are also extraordinarily demanding in terms of their production. We literally fight against the second law of thermodynamics to forge these exquisitely ordered, low-entropy structures out of raw materials that are decidedly high entropy in their messy natural states.
All of which raises the question: Why exactly are we doing this?
An unexpected answer is that it’s not just us doing this. Our dataome is startlingly like a symbiotic organism. Homo sapiens arguably exists only because of our species’ coevolution with this wealth of externalized information: from languages held only in neuronal structures across many generations to our tools and our creations on pottery and cave walls, all the way to today’s online world.
But symbiosis also implies that all parties may have selfish interests. This opens the door to asking whether we’re calling all the shots. After all, in a gene-centered view of biology, all living things are simply temporary vehicles for the propagation and survival of information. In that sense, the dataome is no different, and exactly how information survives is less important than the fact that it can do so. Once that information and its algorithmic underpinnings are in place in the world, the dataome will keep going forever if it can.
A very simple example can be seen in any of the great works of human literature, from Lao Tzu to Shakespeare. These informational packages have found a way to persist through time by attaching themselves to us. We eagerly read them, restructuring our brains to remember them, and we go to great lengths to copy and reproduce these works again and again across the centuries and in many languages and forms. But these texts aren’t just memes; they’re more like an extension of the human phenotype that has its own processes and its own capacity to pressure the world around it to try to ensure its survival.
Throughout life’s three- to four-billion-year history on Earth, it doesn’t seem that anything exactly like this has happened before. On a geologic timescale, the emergence of the human dataome is like a sudden alien invasion or an asteroid impact—changing how the biosphere functions. It’s not just flesh-and-blood life on this world anymore. By a quirk of evolution, our very existence has unleashed a new trick for the restructuring of matter in service of entropy and its cousin, information.
Look around where you are right now, at the walls of your room or the chair you’re sitting on. Or the light you’re reading by and the screen or paper you’re reading these words from. In the end, all these things are here in support of data, of ideas and of the most potent quantity in the universe: information. Our very alien dataome may just be the harbinger of things to come.
References: NASA – NBC News – Scientific American