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The Zoo Hypothesis as Thought Experiment

Imagine a civilization one million years old. As Nick Nielsen points out in today’s essay, the 10,000 year span of our terrestrial civilization would only amount to one percent of the older culture’s lifetime. The ‘zoo hypothesis’ considers extraterrestrials studying us as we study animals in controlled settings. Can a super-civilization study a planetary culture for the whole course of its technological development? Nielsen, an author and strategic analyst, runs a thought experiment on two possible courses of observation, asking how we would be perceived by outsiders, and how they might relate us to the history of their own development.

by J. N. Nielsen


In 1973 John A. Ball wrote a paper published in Icarus called “The Zoo Hypothesis” in which he posited an answer to the Fermi paradox involving the deliberate non-communication of advanced ETI (extraterrestrial intelligence) elsewhere in our universe:

“…the only way that we can understand the apparent non-interaction between ‘them’ and us is to hypothesize that they are deliberately avoiding interaction and that they have set aside the area in which we live as a zoo. The zoo hypothesis predicts that we shall never find them because they do not want to be found and they have the technological ability to insure this.” [1]

Suppose we were being observed at a distance by alien beings. We already have a chilling description of this from the nineteenth century in the opening passage of H. G. Wells’ The War of the Worlds:

“No one would have believed in the last years of the nineteenth century that this world was being watched keenly and closely by intelligences greater than man’s and yet as mortal as his own; that as men busied themselves about their various concerns they were scrutinised and studied, perhaps almost as narrowly as a man with a microscope might scrutinise the transient creatures that swarm and multiply in a drop of water. With infinite complacency men went to and fro over this globe about their little affairs, serene in their assurance of their empire over matter. It is possible that the infusoria under the microscope do the same. No one gave a thought to the older worlds of space as sources of human danger, or thought of them only to dismiss the idea of life upon them as impossible or improbable. It is curious to recall some of the mental habits of those departed days. At most terrestrial men fancied there might be other men upon Mars, perhaps inferior to themselves and ready to welcome a missionary enterprise. Yet across the gulf of space, minds that are to our minds as ours are to those of the beasts that perish, intellects vast and cool and unsympathetic, regarded this earth with envious eyes, and slowly and surely drew their plans against us.”

Like many responses to the Fermi paradox, the zoo hypothesis and its variants make assumptions about the motivations of ETI, and among the first responses to these responses is to question any projection of human motivations onto ETIs. Prior to a survey of the universe entire, with all its life and intelligences (if any), which survey will come (if at all) at a much later stage in the development of our own civilization, the most we can do is to formulate a range of possible ETI motivations (including motivations that do not exist for us, and which must remain unknown unknowns for the time being) and attempt to weight them appropriately in any assessment of the possibility of human/ETI interaction.

The problem of alien minds raises the traditional philosophical difficulty known as the problem of other minds to an even more inaccessible reach of mystery—but this is a philosophical and scientific mystery, not an impenetrable religious mystery [2], and as such we can approach the problem rationally. While we have as yet no empirical basis on which to speculate about alien minds, we can make some deductions about the behaviors and practices of ETIs that have developed an advanced civilization.

Any ETI capable of SETI/METI or interstellar travel would have to have developed something like science (regardless of the motivation for having developed something like science), and science-like activity presupposes science-like observation. Any ETI technologically capable of observing our planet, whether from near or from far, would have developed protocols of observation under controlled conditions, so we could expect the observation of our planet by some ETI to have a science-like character.

In a zoo, we are able to observe the development of individuals of other species. A contemporary zoo does not exist on a scale of time that allows us to observe the evolution of species [3], and is built more for entertainment than for science, but if our terrestrial civilization endures for a sufficient period of time we may yet develop zoo-like institutions that endure over biological scales of time and that allow us to observe not only the development of the individuals of a species, but also the evolution of new species under controlled conditions. Given the zoo hypothesis, we might posit that an alien observer would be able to observe not only the development of individual terrestrial civilizations, but, given the idea that exocivilizations might be of far greater longevity than our civilization (a view held in common by Ball, Sagan [4], Kardashev [5], Norris [6], and many others), it might even be possible to observe the entire evolution of civilization on Earth.

The ten thousand years of terrestrial civilization would constitute only one percent of the lifespan of a million year old supercivilization. Ten thousand years for a million year old civilization would be proportional to one hundred years for a ten thousand year old civilization (in each case, the observed period of time is two orders of magnitude less than the total lifespan on the civilization), and we already have scientific research programs and data collection efforts that have been in continual operation for more than a century.

But allow me to back up for a moment in order to give an example of the sort of thought experiment we would like to conduct at present, illustrated by a particular historical example that highlights our knowledge of our own past in order to see this in the context of ourselves as the more advanced civilization conducting a scientific survey of an earlier and less sophisticated civilization.

spaceship over earth 3

First Thought Experiment

Suppose, as a thought experiment in the counter-factual, that the Cuban Missile Crisis had escalated and resulted in a massive nuclear exchange between the US and the USSR. In this thought experiment, terrestrial civilization came to an end in 1962. [7] Imagine visiting the Earth, as an alien (an alien whose mind has been shaped by 21st century terrestrial science and technology), a sufficiently long period of time after this event that the radioactivity had subsided, seeing the ruins of a global civilization—empty cities, silent highways, decaying factories under a layer of dust, and some insects crawling through the rubble.

Today we have slightly more knowledge about the development of technological civilization than we possessed fifty years ago, and given that industrialized civilization is only about two hundred years old, fifty years constitutes a significant portion of that history (specifically, a quarter of it). [8] From our perspective today, we can see fifty years into the future from the Cuban Missile Crisis. We know what was to come, and so we can, in imagination, assume the perspective of a more technologically advanced civilization in assessing the ruins of the world of 1962, frozen in time by nuclear catastrophe, now a planet-wide archaeological site displaying the material culture of a planetary civilization.

Arriving in the solar system on a mission of scientific exploration, to discover why electromagnetic spectrum transmissions from Earth had suddenly ceased, an alien visitor would first find the Mariner 2 and Venera 1 probes in heliocentric orbit around the sun, along with a handful of other artificial objects, and the now-defunct terrestrial civilization would be immediately classified as one capable of interplanetary travel. The alien visitor would also find two small probes crashed on the lunar surface [9], and numerous Earth satellites, all now dead and silent.

Surveying that ruined world from orbit, the cause of the sudden end to terrestrial transmissions would be obvious: on every continent except Antarctica, the surface of Earth reveals enormous radioactive craters. A keen observer from orbit would find that all these craters are connected to each other by the remains of transportation networks, and such an observer would conclude that the greatest cities of this past civilization had once stood at these junctures. Clearly this was a civilization that had mastered both the technologies of nuclear weapons and ballistic missiles, and had developed these capacities to the point that they were able to extinguish themselves by their own efforts. At this point, the ETI can rule out a natural cause for the extinction of terrestrial civilization.

Large airfields at the edge of former urban sites, and the remains of turbojet aircraft, suggest a worldwide subsonic aviation network was functional prior to the end of the civilization. No supersonic aircraft appeared to have been in service, but the earlier discovery of space probes and artificial satellites confirmed the use of rocketry to achieve escape velocity from the planet. Subsequent investigation would reveal that the civilization of the planet had, not long before destroying itself, inserted a few individuals of their species into planetary orbit and safely returned these same individuals to the planet. Thus the dominant species had just passed several crucial thresholds toward becoming a spacefaring civilization and thereby ensuring itself against the existential risk inherent in being an exclusively planetary civilization. But it had not sufficiently mitigated the existential risk of nuclear war in order to allow it to survive.

The terrestrial civilization had possessed a rudimentary digital computing technology for less than twenty years [10], but this had not yet been fully exploited, as the breakthrough to miniaturization had not yet occurred. [11] Transistors had been invented, but not integrated circuitry. Computing was confined to large mainframes available to business and scientific research. The relative degree of the penetration of computer technology into the ordinary business of life appears to have been at a very low level. Telecommunications primarily consisted of the transmission of analog spoken language and visual signals.

The remnants of the power generation and distribution infrastructure reveal that significant effort had been made to exploit fossil fuels to power industry. A small number of nuclear reactors, all less than ten years old when they ceased operation, had been part of the global electrical grid, with more locations under construction, but this appears to have been a nascent industry not yet fully exploited. There is evidence of research into nuclear fusion, but no evidence of the use of fusion for electrical power generation.

The terrestrial civilization had mastered physical science up to the point of formulating a quantum theory to account for the smallest constituents of nature and a theory of gravity to account for the largest structures of observational cosmology, but it could not yet see its way clear to a comprehensive scientific solution to this impasse. Their physics was stalled at a level of development insufficient to comprehend (and to technologically harness) fundamental forces of cosmology. As further evidence of the civilization’s scientific progress in understanding itself and its place in the universe in scientific terms, the civilization had crossed the SETI threshold [12] and was capable of employing its technology to search for EM spectrum signals over interstellar distances, though it had not yet achieved the energy levels or industrial capacity to make itself known to the wider universe through active messaging (i.e., METI).

All in all, this was a civilization of great promise—global in extent, with the planet connected by transportation and communications infrastructure reaching all demographically significant inhabited areas, but still almost entirely reliant upon fossil fuels employed at a very low efficiency. New technologies were under development at the time of the civilization’s demise, but were far from maturity.


Image credit: Space Studies Institute.

Second Thought Experiment

A similar thought experiment can be performed in regard to our world today. With the experience of imagining our own past frozen in time, we can better appreciate the perspective of a more technologically advanced civilization objectively assessing the capacities and liabilities of the early stages of industrialization and planetary civilization. With this reflection in mind, we can dispense with the macabre conceit of a nuclear extirpation of civilization (which was only a device to dramatically facilitate the first thought experiment) and attempt to imagine an alien observer entering our solar system from outside and viewing our present level of development as a civilization. [13]

To an alien observer, terrestrial civilization would have announced its presence long before any visitor arrived in the solar system, first by its EM spectrum transmissions, and, alerted by these transmissions of a technologically-capable civilization, the alien visitor is surprised to discover that this civilization has already exceeded its own solar system, as it discovers two spacecraft, still viable and transmitting scientific data, having passed beyond the sun’s heliosheath into interstellar space. The alien visitor is impressed by the robust design, still functioning after decades, and still powered by a radioisotope thermoelectric generator. The scientific sophistication is impressive, as evidenced by the range of instrumentation, though still limited in its technological application.

As the alien visitor passes through the outer gas giant planets a few more robotic probes are encountered, more recent and more technically sophisticated than the probes first encountered, and approaching the smaller, rocky planets of the inner solar system there are dozens of robotic probes on Mars in communication with Earth. A cacophony of radio signals connects Earth to its satellites and space probes.

Passing the moon, the ETI detects signs of human visitation, but determines that this dates from several decades previously. An early promise of spacefaring has apparently been followed by a lull in development during which resources that might have gone into exploiting this early push toward space exploration were diverted to other purposes. Later, in a more careful observation of the civilization, it is found that, while military flights routinely employ supersonic aviation, an earlier attempt at commercial supersonic aviation had similarly been abandoned.

Approaching Earth, the night side of the planet is brightly lit by electrical lighting in patterns following transportation networks linking major urban centers, which latter are the brightest visible spectrum points on the surface of the planet. Airports and military installations are strong radar hot spots, while commercial communications networks are continually transmitting over many different bands of the EM spectrum, including a mixture of analog and digital signals encoding spoken language, moving visual images, and data.

The presence of visible light, infrared, and radio telescopes both in orbit and on the planet surface continue to testify to the scientific curiosity of terrestrial civilization. Despite this scientific curiosity, a comprehensive solution to physics at the largest and smallest scales still eludes the civilization, as it had in the earlier period of time considered. Anomalies have appeared within their scientific framework [14], but as yet no systematic solutions to these anomalies are available.

There is a global electricity grid supplied from a variety of energy sources, including a significant percentage of electricity from nuclear fission, but not nuclear fusion, which has not yet been mastered. The presence of a few recent large-scale solar and wind generation facilities suggests that the electrical grid is just at the beginning of a transition away from fossil fuels to renewable energy sources. The development of sustainable sources of electric generation may be compared to the early stages of development of nuclear power from the earlier time period. The increasing level of energy use is such that the supply of the planetary electrical grid by fossil fuels is having a significant impact both on the planetary climate and the social institutions by which the planet is organized.

Even as the large-scale structures of the civilization remain conflicted and inchoate, resulting in institutional friction on a civilizational scale and retarding civilizational development, enterprises likely to materially contribute to a better future for the dominant species on the whole, or which will remain relevant over historically significant scales of time, are economically marginal and involve only a vanishingly small proportion of the total population. Resources are disproportionately made available for retrograde and already antiquated industries at the cost of failing to allocate resources to industries that would facilitate the development of civilization. Much of the civilization’s ideological superstructure is dedicated to producing rationalizations for this suboptimal performance.

While the planet is superficially unified by transportation, telecommunications, and networks of production and distribution, including that for electricity, there is a profound gulf between the ways of life of peoples who have full access to the industrialized economy and those whose relationship to the industrialized economy is only tangential. While the dominant species on the planet has been engaged in a civilizational level of social organization for approximately ten thousand years, the lives of those participating in the industrial economy has been completely transformed even while a significant portion of the population remains in conditions of subsistence agriculture, essentially undifferentiated from the conditions of life untouched by science and technology and almost unchanged over time.

This, too, is a civilization of great promise and great accomplishment, but also a civilization that is troubled in proportion to its growth. Each phase of development introduces additional problems at a civilizational scale. The ETI classifies terrestrial civilization as a “late-adopter spacefaring civilization,” since, having the capacity for large-scale extraterrestrialization [15], and having earlier employed this capacity in a limited way, the dominant species prefers to invest its not inconsiderable economic and industrial capacity in conspicuous consumption and spectacular instances of self-aggrandizement confined within a very narrow horizon of prestige requirements.


Image: A different take on humans in zoos, from a 1960 Twilight Zone episode called ‘People Are Alike All Over.’ Astronaut Roddy McDowall thinks he has found a friendly civilization when he gets to Mars, but he’s in for a surprise. Rod Serling’s closing comment: “Species of animal brought back alive. Interesting similarity in physical characteristics to human beings in head, trunk, arms, legs, hands, feet. Very tiny undeveloped brain. Comes from primitive planet named Earth. Calls himself Samuel Conrad. And he will remain here in his cage with the running water and the electricity and the central heat as long as he lives. Samuel Conrad has found The Twilight Zone.”

Comparing the Two Thought Experiments

If some ETI had visited Earth in 1962, around the time of the Cuban Missile Crisis, perhaps our closest brush with an anthropogenic existential threat, and then again in our present, about fifty years later, making observations as in the two above thought experiments, such an alien would observe both similarities and differences across the span of a half century. The same planetary industrial civilization is in place, although having attained a significantly higher level of technological maturity at the later date. However, despite technological progress, the essential problems of that civilization have remain unresolved as though there were a total lack of interest on part of the dominant species to address the most glaring sources of global catastrophic risk and existential risk.

Although the terrestrial civilization has made some indirect progress in existential risk mitigation, this has primarily come about through limiting the scope and scale wars, which remain as pervasive as at any time in terrestrial history. The changed conditions that have lessened the risk of nuclear war, for example, are not the result of successful planetary initiative to ensure the survival of the dominant species and the biosphere on which it depends.

In the fifty years between observations, terrestrial civilization has passed from exploration of the inner solar system to sending robotic probes into interstellar space, and computing technology has passed from mainframe computers in industry and research to pervasive computing integrated into every aspect of life. The expansion of terrestrial industrial infrastructure that can be observed in this half century has resulted in an increase of several orders of magnitude of energy production and consumption, which demonstrates the vitality of the civilization, but the civilization has been very slow to learn the lessons of mitigating the unintended consequences of industrialization, and as a consequence the level of energy usage has begun to affect the entire biosphere and planetary climate. Industrial pollutants and effluents are measureable throughout the atmosphere and hydrosphere.

Much like the reduction of war risk through the limitation of the scope and scale of wars, the reductions in industrial pollution over the past fifty years have primarily come about through increasing efficiency driven by economic motives, not a purposeful focus on a rational and scientific effort to systematically address civilizational level problems. Future existential risks may not be manageable by this chaotic method, or rather lack of a method.

This is a civilization that has unquestionably achieved a planetary scale, but is utterly and completely unable to initiate and coordinate action on a planetary scale. In other words, this is a civilization that still remains in a stage in which developments are driven by accidental events, while the ability to effectively plan remains confined to meeting the immediate needs of populations (food, shelter, electrical generation, etc.). Even this ability to plan for the provision of immediate needs is compromised by extreme inequality in the allocation of goods. It is an open question whether this civilization can survive the tensions it is creating by its own uneven successes.

Will this planetary civilization endure for a period of time sufficient to advance to a further stage of development? Will it succumb to any of a range of existential risks that threaten exclusively planetary civilization, or will it be the cause of its own demise as the result of existential risks unique to industrial-technological civilization? New existential risks appear to be emerging from the vitality of the civilization at a rate that outpaces efforts at existential risk mitigation on a planetary scale.

While an advanced ETI could choose to focus on the problems and depravities that it could readily identify in terrestrial civilization, it would not be horrified, because it would see itself in the struggles of a younger civilization that it once resembled. It would only be able to recognize terrestrial problems because the more advanced ETI had passed through these stages of development in its own history—not precisely, not in any degree of detail, but in the general course of the development of civilization from a geographically local phenomenon, entirely integrated with the biological processes of a local ecosystem (i.e., biocentric civilization), to a planetary civilization forced by planetary constraints into reluctant cooperation, and eventually to a spacefaring civilization that has transcended its homeworld (and which will perhaps someday converge upon eternal intelligence).

An advanced ETI would not have any reason to fear or to despise terrestrial civilization—any more than a modern army would fear the charge of knights on horseback, or any more than contemporary engineers would despise the efforts of pyramid or cathedral builders—nor would it regard humanity and its civilization as a failure. This civilization could only be, like theirs, a work in progress. For both civilizations, young and old, come from essentially the same materials, were shaped by the same forces, and embody the same laws of nature. No species projects itself across a planet or across the cosmos without having out-competed rivals and threats and asserted itself in the face of adversity. The only thing that separates the two is that the older civilization has a longer record of successes in mitigating existential risks.

Thanks are due to Andreas Folkener for suggesting this exercise to me.

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[1] John A. Ball, “The Zoo Hypothesis,” Icarus, 19, 1973, pp. 347-349. For a variation on the theme of the zoo hypothesis cf. The Wilderness Hypothesis.

[2] On the difference between religious mystery and scientific mystery cf. my post Scientific Curiosity and Existential Need.

[3] There are instances of microevolutionary change that can and have been scientifically observed, but macroevolutionary change such as would result in cladogenesis takes place on a scale of time many orders of magnitude longer than any existing scientific research program, with a few interesting exceptions such as the cichlid fishes of Lake Malawi.

[4] “…the transmitting civilization is likely to have technological and scientific capabilities immensely in excess of our own… The mere fact that they have survived the invention of technology (as we have so far) suggests that such civilizations might be very long lived…” Carl Sagan, “The Recognition of Extraterrestrial Intelligence,” Proceedings of the Royal Society of London. Series B, Biological Sciences, Vol. 189, No. 1095, A Discussion on the Recognition of Alien Life (May 6, 1975), pp. 143-153.

[5] “It is important to note that our civilization, capable of establishing contact with other civilizations, is still very young, and that its age represents an order of magnitude which is very small, possibly zero. Taking into account the fact that the Solar System is a second generation object, that its age is about 5 billion years, and that the age of the oldest objects in the Universe can be about 20 billion years, it becomes clear that the age of other civilizations (in particular the time period throughout which they have been communicating) can be enormously greater than ours.” N. S. Kardashev, “Strategy for the search for extraterrestrial intelligence,” Acta Astronautica, Vol. 6, pp. 33-46, Pergamon Press, 1979.

[6] “…if we do detect ET, the median age is of order 1 billion years. Note that, in this case, the probability of ET being less than one million years older than us is less than 1 part in 1000. Therefore, any successful SETI detection will have detected a civilisation almost certainly at least a million years older than ours, and more probably of order a billion years older.” Ray P. Norris, “How old is ET?” Acta Astronautica, Vol. 47, Nos. 2-9, pp. 73 l-733, 2000.

[7] The idea of a civilization-ending nuclear war was a prominent Cold War cultural theme represented, inter alia, in On the Beach (novel 1957, film 1959), Alas, Babylon (1959), A Canticle for Leibowitz (1960), and Panic in the Year Zero! (film, 1962). On the Beach is an extinction scenario, while the other works examine the collapse of civilizational scale social order in the aftermath of nuclear war. Those contemplating the possibility of the Cuban Missile Crisis resulting in a MAD scenario had these imaginary models to draw upon in considering the consequences of such an event.

[8] If the past fifty years represents approximately a quarter of the total lifespan of industrial-technological civilization, and if we taken the total lifespan of agrarian-ecclesiastical civilization as being about ten thousand years, from the origins of agriculture to the industrial revolution, then a proportional period of time for the observation of agrarian-ecclesiastical civilization would be a lapse of about 2,500 years. In other words, if we were to arrive on Earth about the time of the industrial revolution (during the late eighteenth century) and look back upon the whole of civilization to date, we would have to look back to what Karl Jaspers called the Axial Age in order to grasp a proportional period of time in agrarian-ecclesiastical civilization as we today have as a perspective on the industrial-technological civilization of 1962.

[9] Luna 2 made a planned hard (crash) landing on the moon on 14 September 1959; Ranger 4 crash landed on the far side of the moon 26 April 1962, failing to return data before impact. The Ranger 3 spacecraft missed a planned flyby of the moon and instead entered into a heliocentric orbit, and presumably could be found as well by an ETI arriving from deep space, along with Venera 1 and Mariner 2. Ranger 5 launched during the Cuban Missile Crisis on 18 October 1962 (the Cuban Missile Crisis occurred during 14-28 October 1962) and it, too, missed its planned impact on the moon and entered into heliocentric orbit.

[10] The first electronic digital computer was the Colossus, built at Bletchley Park in 1943, designed by Tommy Flowers for the top secret Ultra project of breaking Axis ciphers based on the Enigma machine and its variants. Due to the secrecy of the program all the Colossus computers and plans were destroyed. The decision taken by Churchill to destroy all the Colossus computers at the end of the war was, I believe, motivated at least in part by Churchill’s heroic conception of history (on which cf. The Heroic Conception of Civilization) in which computers could be treated as a modern parallel to Greek Fire. It would be another thought experiment to consider how subsequent history might have been different if this early example of digital computing technology had been made widely available rather than being hidden from public view.

[11] The miniaturization of electronics was largely a result of the effort by the space program to make electronic components lighter for purposes of liftoff—lighter electronics meant a proportionally larger science payload to takeoff weight.

[12] Project Ozma was conducted in 1960. We now know that there are planetary systems at Tau Ceti and Epsilon Eridani, possibly in these stars’ habitable zone. If an advanced technological civilization had been present on any of these planets and had been powerfully transmitting in our direction (because they would already have been able to determine that there was a planet in our solar system with a biosphere and an atmosphere with industrial pollutants), Frank Drake would have received these signals as soon as he had switched on his apparatus.

[13] In my post Astrobiological Thought Experiment I developed another thought experiment placing ourselves in an alien zoo in a more zoo-like context; in this present scenario, human beings and their civilization are observed under conditions more like that of a wildlife sanctuary—a scenario also covered in Ball’s paper cited above: “Occasionally we set aside wilderness areas, wildlife sanctuaries, or zoos in which other species (or other civilizations) are allowed to develop naturally, i.e., interacting very little with man.”

[14] Among these anomalies I would count the absence of a unified field theory, dark matter, dark energy, the absence of a scientific theory of consciousness (a working hypothesis that could be considered the basis of an ongoing scientific research program), and even the Fermi paradox for what it implies for astrobiology. In addition to anomalies there are predictions and projections made on the basis of current science, but which go beyond the available science sensu stricto. Due to the underdetermination of theory by evidence one must expect that there will always be non sequiters, but logical errors sometimes are transmuted into an ideological program associated with, but not identical to, science (and sometimes called “scientism”). The ideology of science can, in turn, come to retard scientific progress when it is integrated into scientific institutions and is employed as a pretext to marginalize fields of research that call that ideology into question.

[15] The ETI performing this civilizational survey can only with hesitation identify terrestrial civilization as a “late-adopter spacefaring civilization,” as there are no signs at present of a breakthrough to demographically significant extraterrestrialization, although the ETI prefers to remain optimistic, as nothing in the survey reveals a disability to pursue this course of action, only a disinclination. “Extraterrestrialization” is the term I employ for the demographically significant presence of a dominant species beyond the biosphere of its homeworld, i.e., demographically significant spacefaring. For present purposes, “demographically significant” may be defined as a biologically viable and independent population. I suppose I should adopt some other term — extraplanetary? extraplanetarization? transplanetary?—so as to avoid the reference to terrestrial civilization, which is admittedly anthropocentric.


Comments on this entry are closed.

  • DCM June 26, 2015, 12:30

    I’m leery of speculating in much detail about aliens and their motives or thoughts, but conflict among humans spurs progress in technology and other areas. Note that the end of the Cold War brought the end of rapid space exploration. Few persons or societies can endure peace without falling into lethargy.

  • Marshall Eubanks June 26, 2015, 12:59

    Imagine that there is a civilization in the galaxy that is 6 billion years old (a very reasonable age from the first burst of star formation 10 billion years or so ago). Even if their probes can only travel at 0.001 c, they would have (if they cared) surveyed the entire galaxy, every star, planet and rock worth consideration long before the formation of the solar system. If they care to, they would have known about our planetary system more or less from its birth, and would know about our biological potential. If they want to monitor us, we are being monitored. If they want to communicate with us, we would certainly know it, so they aren’t, at least right now. They certainly know what sort of blokes we are – they have probably literally seen our likes a million times before.

    Given the long time required for communication on a galactic scale, and the long time horizons of creatures that might be themselves billions of years old, if they do want to talk to the likes of us, I figure they will get around to it in 5 or 10 thousand years or so. Waiting a short while like that would, after all, weed out the flash in the pans.

  • Michael Chorost June 26, 2015, 17:42

    I’m not sure I understand what hypothesis this thought experiment is testing, or what conclusion it’s coming to. Nonetheless, I like its conclusion: “An advanced ETI would not have any reason to fear or to despise terrestrial civilization…This civilization could only be, like theirs, a work in progress.” I think it’s too often assumed that an advanced civilization would be uninterested in ours. Humans are very interested in ostensibly “less evolved” creatures on this planet; scientists study social insects and dolphins, and people have deep relationships with cats, dogs,horses, and elephants. It’s also too often assumed that an advanced civilization would have nothing to learn from us, as if civilizational development always had to proceed on exactly the same path and hit exactly the same milestones. I think it’s quite possible that aliens would be as interested in our art as we are in the Chauvet cave paintings. The essence of aesthetic appreciation is putting oneself imaginatively into the position of an Other, and the more Other it is, the better and richer the experience. I would hope that an advanced civilization would have wisdom, curiosity, and compassion, and — as you say — the recognition that every civilization is a work in progress.

  • Stan Erickson June 26, 2015, 18:58

    I don’t see why they would want to observe us. Surely not for amusement, as they would have developed media more than adequate for keeping themselves occupied. And not for science, as they would already have figured out everything they could possibly learn by tediously observing us. Perhaps it is mankind’s collective ego which makes us think we are worth some alien civilization’s time.

  • Harold Daughety June 26, 2015, 23:05

    The one fault I see in this thought experiment is that these ET’s are exhibiting human motives and behaviors. We are an infantile race, still fighting on the playground. When and if we are ever fully evolved, maybe we will have nothing to fear from ourselves. To assume the ET’s are curious and expend resources to study us is an anthropomorphism.
    I think our speculative fiction has encouraged us to expect development of FTL flight. There is no evidence that interstellar spacefaring civilizations have ever existed or that they can exist. If they do, they most likely do not resemble us other than possibly in morphology.

  • Brian June 27, 2015, 0:35

    they would study us for the same reason we study single cell organisms. or they want to record all know all life in the universe. Actually when talking about an advanced alien civilization why is high tech snobbery assumed? there really is not record of advanced human civilizations ignoring less advanced ones, sometimes militaristically but sometimes peacefully, nor have humans really ignored animal life on the earth. Why is it assumed that an advanced civilization would ignore us? are they God and can’t be bothered? or is it taking the psychology of a smart person who wants to avoid a dumb one. How come were the only one who showed up to the party so far we assume no one wants to come rather than no one knows there is one on earth?

  • NS June 27, 2015, 1:41

    There are a lot of questions in biology that can only be answered if we observe life that evolved independently of that on Earth. The same is true of intelligence/culture/technology. We will certainly want to study whatever examples of these we can find, and they will presumably have the same interest in us.

  • TheAnt June 27, 2015, 3:08

    That notion that such a civilization would focus all their attention on Earth as is envisioned in comic books or by UFO enthusiasts are ofc silly.
    Yet I agree that Earth might have been of interest in academic research at one time or other either by specialized equipment.
    A civilization as described in the main text might have remote sensing equipment that would make a space based TPF scope compare to pre-humanity’s first use of a blunt stick.

    So they would know that Earth is a life bearing planet, and as a follow up perhaps send a probe. No reason it would have been here recently, that visit could as well has been during the Cambrian age. There’s a limit to remote sensing regardless of the specialization, so perhaps one probe is sent to find out what kind of genetic code and how it work for Earth organisms.

    So the zoo hypothesis might be close to the mark but might not be spot on. Earth could equally well be seen as a bioreserve, and the best we can hope for is that the super-civilization do not consider us one invasive species that is hellbent on ruin this biosphere completely.

  • Nick Nielsen June 27, 2015, 4:12

    It is interesting to note in the comments so far that antithetical responses have emerged. Michael Chorost wrote, “I think it’s too often assumed that an advanced civilization would be uninterested in ours.” And Stan Erickson wrote, “I don’t see why they would want to observe us.” DCM wrote, “I’m leery of speculating in much detail about aliens and their motives or thoughts…”

    I think we’re all leery of speculating on the motives of ETI, and that is why I explicitly addressed the question of considering ETI motivations. Any ETI that can observe us will have developed scientific protocols of observation regardless of their motivation, given the difficulty of observation over interstellar distances.

    I am with Michael Chorost in thinking that we would be worth observing. Stan Erickson dismisses the idea that human science would be worth observing, and that human beings would be entertaining to watch. I think another species would be fascinating to observe, and the more developed and the more different their cognitive endowment, the more interesting they would be.

    We don’t need to recur to ETI motivations to suppose so. If an ETI has its origins in a planetary biosphere (even at one remove, e.g., if it is artificial and was constructed by organic agents), any naturally occurring intelligence is going to admit of variation and diversity. The kind of mind that would be drawn to the scientific investigation of other intelligent species would be much like the kind of human minds that engage in scientific work.

    Most people aren’t scientists. Most people don’t study, say, botany, but the few who do have created a substantial scientific literature and have made science what it is today. Science might be a minority undertaking, but any civilization with an interstellar technology will have some kind of science, and the existence of science implies the existence of scientific investigators.

  • DCM June 27, 2015, 4:27

    Another tired assumption. Mankind has no ego. Ego is a construct of psychoanalysis referring to the mental functions dealing with reality at least as perceived.
    On the other hand, pondering being observed is at least a survival process.
    Please, free yourselves from automatic negative beliefs and assumptions abut humans. They stand in the way of trying to imagine what aliens may be like; the aliens’ motives aren’t going to be functions of our passing cultural quirks.

  • Anthony Mugan June 27, 2015, 5:59

    I think you raise an important point here. The sheer enormity of the available time and space available tends to make me think the plausible solutions to the Fermi paradox are towards the two extremes of the spectrum. I other words either something close to the Zoo hypothesis or there may be an error in our current thinking about the origin and evolution of life and we are truly alone.

    The odds seem to me to favour the Zoo hypothesis whilst more intermediae solutions such as civilisations killing themselves off seem less credible as it would only take one to survive to the point of interstellar travel

  • J. Jason Wentworth June 27, 2015, 7:24

    The Zoo Hypothesis has always seemed–to me, at least–like a way to sidestep a more obvious reason why we have found no other scientifically/technologically advanced races (or been found by them): They either don’t exist, or they are so rare that the nearest one has yet to hear any of Earth’s radar, radio, or television emissions (assuming that they could, as such unintended interstellar transmissions are very feeble at such immense distances).

    Even if life is fairly common, it does not necessarily follow that intelligent life (especially of the scientific/technological variety) is. Any race that could detect spectral signatures of life on exoplanets might be overwhelmed with possible choices–which worlds might have someone at home with whom they could communicate, and which ones host only plants and lower animals, or non-technological yet intelligent beings who don’t have radio and television? (Having that many choices of life-bearing worlds would be a *good* problem to have, though!) Also:

    It’s perhaps ironic that the more credible-sounding reports of what have come to be called UFOs (especially those reports that pre-date widespread human interest in–and belief in the possibility of–space travel) give the impression that any intelligence that might be behind them actively *avoids* contact with human beings. (I take no position one way or another regarding what UFOs might be, since the sightings have no *one* stimulus, and because many of the “objects” don’t seem to be solid or artificial–I prefer the term UAP, for Unidentified Aerial Phenomena.)

    The reported objects (and reported occupants, when noted) seem very interested in Earth’s flora and fauna and in human infrastructure and transportation systems, but avoid contact with humans (in the *credible-sounding* reports; the abductions, rides, and “contactee” accounts sound just plain silly). One could be tempted to say that “They’re being good anthropologists, studying a less advanced culture and taking pains to avoid interference with its natural development.” If human “true astronauts” (as Dr. Robert Forward referred to the starship crews in his novels) ever find themselves in the position of the hypothetical UFO occupants with regard to a less advanced culture, they might very well conduct their operations in a similar way.

  • Anthony Mugan June 27, 2015, 9:26

    A challenge for the Zoo hypothesis is that if it is a 100% effective strategy then it would be impossible to test. Fortunately Murphy’s law is likely to be universal and errors / malfunctions will occurr.
    The assumption that the aim is 100% invisibility is also questionable. Some risk in detection may be operationally necessary for certain purposes. We also can see an interesting development in ‘ambiguous’ strategies in human warfare. Such ambiguous approaches may be useful from a patios perspective. These scenarios may create testable possibilities…TBC

  • Anthony Mugan June 27, 2015, 9:27

    Patios = psyops

  • Lorne Wardell June 27, 2015, 12:55

    An idea I have not yet seen here is that alien civilizations could exist in hierarchies of knowledge, and motivations would differ depending on their status relationships. If we are being studied for scientific reasons, the studying itself may have been instigated by a yet higher civilization which is evaluating the studying abilities of a civilization much closer in development to our own. Professors insist that degree candidates exhibit the designing of experiments and submit analysis of the results—not because the Professor doesn`t already know, but because the student needs to learn how to find out.

  • Cambias June 27, 2015, 14:06

    No one has ever explained WHY an alien civilization which (per our hypothesis) wants to learn about Earth, its biosphere, and human civilization, would avoid contact. Surely the most efficient way to learn about a world with intelligent inhabitants is to go talk to them and find out what they’ve already discovered about their planet.

    The only reason for hiding would be if the aliens had some kind of Rousseau/Roddenberry notion that contact with a more technologically advanced civilization would somehow “corrupt” or “distort” the contactee civilization. While some cultures may believe that, it’s equally (if not more) probable that they will consider themselves to have a duty to spread knowledge and/or moral instruction to the benighted Earthlings.

  • Anthony Mugan June 27, 2015, 14:23

    To continue ( and hopefully avoid the perils of predictive text), testing the zoo hypothesis depends on the zoo being ‘leaky’ to some extent, either accidentally or intentionally.
    In principle it may be possible to compare predictions of specific technologies ( e.g. propulsion models) against occasional unusual observations. This unfortunately comes into controversial territory and I doubt if in practice it will be either possible to convincingly extract a ‘signal’ from the mass of noise or for anyone to get away with such a study without damaging an academic career….which is shame
    ( dare I mention Paul R Hill 1995 work and Hal Puthoff’s 2010 paper in JBIS in this context…no, better not…!!!)

  • Robert June 27, 2015, 15:17

    I have always found fascinating the reports of military interactions with apparent UFO’s both in official records and off the record comments by military authorities. Personally, I think humanity is not ready for knowledge that we are not alone (if that truly is the case) and such a revelation would be too disruptive at this point in time.

    I would make no assumptions as to how aliens organize themselves or would potentially interact with humanity or that technical advancement means social or moral advancement.

  • Stan Erickson June 28, 2015, 0:45

    The concept that aliens would want to study us comes from the assumption that they are simply a civilization at our level of science knowledge with some interstellar transportation added in. Far from reasonable. They would have likely finished investigating all the sciences, including anthropology, psychology, genetics and any other that might be informed by studying our existence. We study such things because we are still ignorant about them; they would not be. http://stanericksonsblog.blogspot.com/2015/06/asymptotic-technology.html

  • Wojciech J June 28, 2015, 4:37

    I will go over some issues with this article, but first I would like point out one quite serious mistake:
    The Cuban Missile Crisis was never a danger to existence of human civilization. If nuclear confrontation would occur, it would result in destruction of Soviet Union, massive damage to USA(but not its complete destruction) and Europe. Size of Soviet nuclear arsenal capable of reaching US at the time was too small to destroy it completely (in contrast to US own nuclear forces which were capable of destroying Soviets at the time), they simply didn’t have enough capable ICBM’s to reach North America in substantial numbers(hence the need to put missiles in Cuba). That is not to say USA wouldn’t be hit, but the enormous damage would be suffered by a couple large cities.There would be millions of casualties there, but as a whole most of population of USA would survive the nuclear attack(there would be further casualties due to food shortages, diseases and rioting later, but nothing that would mean the end of the country)
    Plenty of countries in Southern Hemisphere and Asia would survive. The author states that every continent would be littered with nuclear craters but outside of North America, Europe and Soviet Asia there weren’t many targets of opportunity for a still limited nuclear arsenal in the 60s.
    The world would be much grimmer, probably authoritarian place facing century or two of technological stagnation(probably early 20th/late 19th century technological level) but it wouldn’t be destroyed.
    The Soviets realized that the were outgunned at the time, and that was one of the reasons they backed down.

  • Wojciech J June 28, 2015, 4:57

    “Cambias June 27, 2015 at 14:06

    No one has ever explained WHY an alien civilization which (per our hypothesis) wants to learn about Earth, its biosphere, and human civilization, would avoid contact. ”
    Cultural and technological uniqueness. A civilization millions/billions of years older than us would be possibly be interested in preserving new and innovative ways of thinking and technological advancement they weren’t able to envision.
    A culture like ours when faced with an advanced other society would likely adopt their methods for resolving technological and cultural issues.
    Having us develop on our own would allow them to cultivate technological civilizations capable of providing new insight into science and culture(of course in million years, but they can wait).

  • Wojciech J June 28, 2015, 5:03

    Having read the other comments I have to admit my thinking is similar:a civilization older than us by even a couple of million years would be able to catalog and identify all habitable worlds in the Galaxy by telescopic observations. If they would like to observe us, they would do so since eons.
    They would be able also to detect first technological advancements either by imagery provided by vast telescopes on solar system scale.
    If they would like to be seen, they would be seen. But it is likely that cultural contact with such highly advanced culture would be disastrous to our own growth. It is then likely they either don’t exist/are uninterested/don’t want to be seen/we see their works but can’t distinguish them from natural events(ie hypervelocity stars, dyson spheres signatures etc).
    Also a interesting statement in the article:
    ”Any ETI capable of SETI/METI or interstellar travel would have to have developed something like science”
    Peter Watts in his Blindsight offers an interesting take on this, and rather plausible that isn’t necessarily so.

  • J. Jason Wentworth June 28, 2015, 6:58

    Anthony Mugan, I’m not convinced that we’re being visited now, but…while I have not read Hal Puthoff’s 2010 JBIS paper, I -have- read NASA (and before that, NACA) engineer Paul R. Hill’s book “Unconventional Flying Objects: A Scientific Analysis.” Having analyzed in great detail–from an engineer’s perspective–his two sightings and hypothesized the types of propulsion systems that could produce such phenomenal performance, I give his work considerable credence. Also:

    *IF* (which I don’t know enough to “choose sides” regarding, one way or another) some governments do know that we’re being visited, but are keeping such knowledge to themselves (I rather doubt it, but I don’t know), there is an excellent selfish, political reason why they might do so, which has nothing to do with “fear of panicking the populace”:

    If it became known that we are being visited by a more advanced civilization (particularly a non-hostile one), it would be obvious that the aliens [1] had solved or avoided the problem of intra-racial warfare that plagues humanity, and [2] had achieved planetary societal and economic unity. Knowing that another race had achieved these things, people (especially younger people) around the world might stop regarding themselves first as Americans, Russians, etc., and begin thinking of themselves as Earthlings first (I prefer the planetary origin descriptor “Terran” to “Earthling”), wanting to transcend our current tribal divisions among ourselves in order to achieve what the aliens had. This would be the *last* thing that national governments–of any kind, anywhere–would want to happen, because governments want their citizens to be loyal to *them*, not to humanity as a whole. Even a radio or laser transmission from another civilization might have that “dangerous” (to governments) effect, depending on what the aliens told us.

  • Marshall Eubanks June 28, 2015, 13:57

    “Cambias June 27, 2015 at 14:06

    No one has ever explained WHY an alien civilization which (per our hypothesis) wants to learn about Earth, its biosphere, and human civilization, would avoid contact. ”

    I don’t think they would. I just think that a billion year old civilization is probably comfortable with communications / contact lags that are longer than the entire duration of our civilization. It could easily take 20,000 years for a message to get to the Galactic Bulge and back. If an alert went out with the building of the Great Pyramid, a response might be 5 or 10 or 15 thousand years in the future. (Even a more unlikely million year old civilization might be comfortable with such lags.)

  • James Stilwell June 28, 2015, 14:05

    A great post…
    A million year old civilization would be an immortal one and cease multiplying for the sake their sanity…They would be gods…If they are humanoids we are lucky and they would be living among us seeking companionship…they would be different in subtle ways and are Impostors among us…what would be more amusing to a god than applying game theory to brain evolution…
    You should talk to Hari Seldon and if you can’t…channel him…

  • Robert June 28, 2015, 19:44

    “No one has ever explained WHY an alien civilization which (per our hypothesis) wants to learn about Earth, its biosphere, and human civilization, would avoid contact. ”

    You obviously have not watched enough Star Trek! :) the Prime Directive prohibited Federation personnel from interfering in the development of an alien society in any way, especially a lesser developed one. But seriously, science fiction writers have spent decades thinking about these ideas. Also,
    a million year old civilization might actually be an extremely stable society perhaps to the point of stagnation. If nothing else, human societies are dynamic. Perhaps the Old Ones find that interesting.


  • Al Jackson June 28, 2015, 21:29

    In prose science fiction there is a sort of variant of the Zoo Hypothesis, that is an advanced civilization makes contact with purpose of controlling and mentoring humankind’s access to the stars. Usually Earth’s warlike past is the stain. The scenario goes that we finally attain interstellar flight , then are discovered by a ‘galactic federation’ (say) and gently but emphatically escorted back to the Solar System until Terran civilization is more mature.
    I love the variant by Andre Norton, Star Guard (1955), the ‘federation’ finds a role for advanced (potentially) ‘warlike’ civilizations like our as mercenaries. Go off planet? Sure, but only if one signs on as a soldier to serve on the planets of even less than civilized cultures than even us! Her 1955 novel quite cleverly uses Xenophon’s the Anabasis as a base for the story.

  • Tom June 28, 2015, 21:58

    I’m very biased on the ‘alien’ question. We’re here, so where are the rest of the lifeforms beyond our Earth and solar system?
    Obvious, everyone is on holiday.

    This one is probably a longshot.

    Our warfare and technology wouldn’t raise the attention of very sophisticated beings. But smart creatures might have a network across the galaxy to support its own endeavors of exploration…. this is speculative of course…. genius cultures may have discovered the formula for ‘everything’ and exploration would be as useless as operating ouija boards?

    I guess will have to get busted going thru they’re garbage before we know the answer?

  • Michael Spencer June 29, 2015, 7:29

    Just a small point. You write “the reductions in industrial pollution over the past fifty years have primarily come about through increasing efficiency driven by economic motives”. Without quibbling over the word ‘primarily, I would point out that it was governmental action (In the US, the EPA, for instance) that forced whatever changes needed to clean up our air, water, and soil. Europe had a similar history.

  • Anthony Mugan June 29, 2015, 10:41

    A further thought experiment…how long could a zoo be maintained? It would certainly fail when the observed civilisation attains interstellar capability. At what point and in what manner do you begin to ‘prepare the ground’ for that eventuality?
    At this point we are in danger of being anthropocentric in our reasoning but an ambiguous strategy may be useful in that scenario…?

  • david lewis June 30, 2015, 8:15

    Horrible analogy – looking back at 1962 from the view point of 2015 in no way compares to a million-year-old civilization looking at our current civilization.

    For one thing, the people in 1962 were just as intelligent as we are. In a million years a civilization that has mastered genetics would be altering their bodies and minds, making each new generation a massive evolutionary leap. Even a 10% increase per 1000 years would give them an IQ of 2,000,000,000,000,000,000,000,000,000,000,000,000,000,000. What would even one of our greatest geniuses with an IQ of less than 300 have to say to such creatures.

    They would have the tools to take a DNA sample of not just our human DNA, but also from the many symbiotes we carry with us. What passes for computers for them, assuming they aren’t themselves computers, would tell them more about us in a second than we’ve learned about ourselves since time began. (And we wouldn’t even know the samples were taken.)

    Their instruments would tell them the same about every species on Earth, and they would have the knowledge to better interpret how all those species interact than we do.

    They would have knowledge of the histories of a billion worlds, and be able to apply that to our world. How stars and planets form would be well know to them, telling then more about of planetary evolution in an instant than what our best experts could tell them in a lifetime.

    Our computer networks would be an open book to them, and as a side-issue they might look through them, and get a laugh at the silly superstitions we have that we claim as science.

    When was the last time you stopped, and asked the scum in a puddle for directions? For that matter, how many of you consider said scum to be intelligent?

  • Robert June 30, 2015, 14:02

    Established science considers modern humanity to have arrived around 200,000 years ago. Some think it may be even older than that. It may just be an accident of history that the path to large scale social order (such as it is) and technology started only a few thousand years ago. Suppose it had been triggered near the beginning. Our technical civilization would be that old itself or perhaps older. Perhaps we would be a spacefaring civilization having explored the galaxy for nearly the last 200,000 years. Would we actually be all that different? Probably not. I doubt any biology woud support the exponential IQ level mentioned above.

  • Mark Zambelli June 30, 2015, 14:28

    Option A =we’re alone (or immensely isolated) => end of discussion.
    Option B =we’re not alone => lots and lots of things to discuss; yay!

    Even if option A turns out to ultimately be true (boo!), I’d much rather think about the implications and contradictions of option B and the zoo-hypothesis is a good one.

    Firstly, why study us? The previous comments should provide enough reasons bundled together under ‘Inquistiveness’. But, to appeal to the naysayers who don’t regard human accomplishments or societal developments and interactions as having any value or interest (?) to an arbitrarily advanced ETI, how about studying us and other races as merely an exercise in ground-truthing their simulations?

    The way I see it, curiosity is most definitley NOT an anthropomorphic issue… it’s not even a mammalian issue… so while “trying to guess an ETI motivation” is often deemed a fools-errand, we can in all seriousness be justified in considerring certain qualia and commonalities (such as survival instinct for example) that would be applicable when viewed in a ‘non-anthropocentric’ setting.

    So, if we are in a zoo it may be for any of several reasons. Primarily, if your interest is in purely studying something for some reason, then any attempt to intervene will spoil the result (maybe intervention comes later) and the result may hinge on un-sullied data.

    Also, what’s wrong with study for studies sake? Even with a near omniscient ETI in the mix as zookeepers, and assuming life is plentiful, each and every instance should be unique; some qualities shared, some completely diiferent. Maybe the randomness of life over evolutionary time is just too hard to model so a hands-on approach with zoos is better. Of course, for a MYr or GYr civ, then we are much more likely to currently be in one of their Ancestor-Simulations and not much more than invested 1’s and 0’s…yay?

    But I’ve always had the thought in my mind of what if there is no way to make a zoo 100% secure? All it takes is some self-interested party to ‘flick their tentacles / thumb their facial olfactory appendage’ at authority and contravene the imposed isolation somehow and introduce themselves (maybe not by avoiding one of Iain M Banks’ godlike guardians of his planets of the dead [Consider Phlebas] but by ‘simply’ (advanced ETI remember) popping a wormhole in our laps and stepping out with a) an olive branch and a 4D Klein-bottle of simulated Romulan Ale (they may heve seen the files on our Sci-Fantasy transmissions), or b) a raised, nasty-looking energy weapon (note: option b) is understood to be constructed from Balonium and employed fantastically by Tim Burton).

    So… Q. Could a secure perimeter be setup and enforced?

    Despite the Star Trek conotations I think the Prime Directive is a good idea and may be a very valid one. It also stipulates a ‘contact event’ as a prerequiste… for Trek it is the successful application of Warp Drive… for actual hypothetical zoo members such as us who knows?

    The zoo hypothesis stands above anthropocentrism IMHO as it does not appeal to any motives soley our own to be at play anywhere in the Galaxy.

    I’ll leave with a poser… what if there is a heirarchy of zoos and we are on the lowest rung. Maybe there’s some Babylon5 ‘Elder’-like race out there being watched from The Bulk while they are peering at our manifold while watching the galactic-spying watchers of our watchers…

  • Curtis Cunningham June 30, 2015, 16:27

    I enjoyed the premis of the article and the thought process behind it, the scenarios, etc. but will admit I rapidly lost interest.

    The article opens with comments that we can’t make any assumptions about alien motivations, but then the scenarios are heavily coloured with adjectives along the lines of “the aliens nevertheless were impressed by our (some achievement or other)”. I’d have trimmed everyone of one out and kept in mind the fact we’ve no grasp of what might be going through an advanced alien mind when looking at us.

    Neil de grasse tyson has a sobering view worth contemplating…


    Also, we may not be the most intelligent form of life in this planet…


    I’m reminded of that quote “if you judge a fish by its ability to climb a tree, it’ll spend its whole life thinking it’s stupid” – I’m sure that’s incorrect, but you get the gist. I’d correct that by saying “the person doing the judging will spend their life stupid!”.

    It would make way more sense that if aliens come here to help anyone, they’re coming to save the most intelligent life form (whales!) from extinction by the most dangerous – us.

  • Alex Tolley June 30, 2015, 20:28

    A zoo with invisible captors is rather rather like the omnipotent invisible sky fairy. Is it equally fantastical?

  • Mark Zambelli July 1, 2015, 7:26

    What exactly is this problem people seem to be having with the main article?

    How else is Nick Neilson supposed to stimulate our thoughts on this specialist sub-argument of the Fermi Question? He’s a human, discussing only the ‘Zoo Hypothesis’ with fellow humans. Of course the text will be heavily anthropocentric as we ‘try’ to cogitate what ‘possible’ motives could be at work ‘if’ the zoo is regarded as being a valid consideration. How better to engage us in this line of reasoning than to ask us to put ourselves in their place… knowing that this is not an accurate way to decipher alien thought-processes is irrelevant to the question of “Could a zoo be in place?”, and should be treated as a seperate consideration on alien psychology.

    If a zoo is in place then we can offer some non-anthropocentric motives, some anthropocentric ones and, finally, be ever aware that there will be options that we haven’t considered or will never be able to consider. There’s nothing wrong with putting ourselves in their position to try and stimulate ideas about how we would feel if it was us doing the spying. Just because a bunch of primates have come up with the zoo hypothesis does not mean therefore that no ETI would ever be able to come up with it too as if it will only ever be a human idea.

    If a zoo is enforced around Sol then the ETI responsible must also think similarly to us in this area. If the ZH is wrong then there could still be other explanations for the Fermi Question other than ‘we are truly alone’.

  • david lewis July 1, 2015, 10:27

    ” Probably not. I doubt any biology woud support the exponential IQ level mentioned above.”

    Certainly no biology we know of, but chimps probably can’t conceive of building a supercomputer. That’s not an argument that supercomputers are impossible; just because we can’t conceive of creatures so vastly intelligent doesn’t mean they can’t exist. Not that the difference need be so great to make them gods to us.

    Personally I’m quite impressed with the way we can organize to build massive skyscrapers, or ocean-going ships, and feel little need to impress creatures from another world, assuming such creatures even exist. Of course I’m also impressed by how stupid we humans are, and the varied ways we’ve come up with to justify war and genocide – truly we are a very inventive species.

  • Doug M. July 1, 2015, 14:34

    Not to nitpick, but I’m wondering how the aliens are able to find all our probes. Cassini? Microscopic on an astronomical scale, and its radio signals to Earth are highly directional. The Voyagers and New Horizons? Unless you’re assuming some magical technology, pretty much impossible.

    Doug M.

  • Doug M. July 1, 2015, 14:39

    ‘The ETI classifies terrestrial civilization as a “late-adopter spacefaring civilization,”’

    …because we’ve had the ability to travel outside the atmosphere for, woo, just over fifty years, and we haven’t colonized space en masse yet? Man, that’s one judgmental million-year-old civilization.

    Doug M.

  • Rob Henry July 2, 2015, 19:12

    I have several points to make.

    First@ David Lewis, IQ itself is an exponential measure of intelligence, normalised to the white British or American populatiom median of IQ100, with each ten point rise adding the problem solving power of 2-4 of those ten points behind (the exact figure is hard to work out and finding it not a priority in psychometric circles).

    Next, the zoo hypothesis is only viable if the zookeeper’s only interest is in studying humans, as it involves withholding their superior knowledge from us of how to preserve Earth’s wildlife – a task that we are already desperate to help them with.

    and last, Curtis Cunningham wrote…
    “It would make way more sense that if aliens come here to help anyone, they’re coming to save the most intelligent life form (whales!) from extinction by the most dangerous – us.”

    I doubt “whales” are more intelligent than us, their large brains being offset by the inefficiencies of unihemispheric sleep. That said, I have become fixated by the one exception – sperm whales. In addition to using normal bihemispheric sleep this species is,
    1. The only species with an ecological footprint comparable in size to ours
    2. Has the largest brain known to human science.
    3. Has, by far, the lowest proportion of their brain devoted to body control of any studied mammal.
    4. Are the only animal known for which the culture to which they belong is a greater predictor of reproductive success than their geographic location or genetic makeup.
    5. The only animal whose vocalisations break down under standard Duda-Hart analysis to a complexity greater than the typical vocabulary of human language.

    I have become so concerned that the possibility of sperm whales having human level intelligence is being understudied that I started my own website to that purpose!

  • Marshall Eubanks July 2, 2015, 20:48

    Rob Henry – Can you provide a link to that Sperm Whale website?

  • Anthony Mugan July 3, 2015, 1:58

    @ Rob Henry
    Interesting point about sperm whales. I don’t agree that the Zoo hypothesis would only relate to an interest in humans though. Observing a full biosphere evolve may be quite interesting. Our emergence as a technological civilisation may require a policy change at some point to reflect the inevitable breakdown of the Zoo ( unless we destroy ourselves). The zoo may therefore already be leaky or become so, which is fortunate as that circumstance is the only one in which the hypothesis is potentially testable.

  • Rob Henry July 3, 2015, 17:28

    @Marshall Eubanks my Sperm Whale Website is cachelot.com. Recently I found another website claiming that sperm whale vocalisations were, by far, the most interesting among cetaceans, but they found it on a different ‘channel’.

    To me it was Mike van der Schaar’s doctoral thesis indicating that even its simplest two coda were expressed with > 180 discretely different interclick interval fine tunings. To DAREWIN (their website is www,darewin.com) it was that each click contained internal fine structure that was reproduced in hundreds of different ways.

  • Curtis Cunningham July 3, 2015, 18:48

    @Rob Henry, you’re deciding to disregard my comment while it’s clear you didn’t read the resource I provided on Cetaceans. In it there is feedback from specialists studying these animals for decades that have some pretty mind expanding opinions. Note also that Cetaceans are the *only* species in the planet so far found to have an entire brain layer *on top of* a neocortex. Worth rephrasing – they have 3 similar brain layers as us, then they have another on top, encasing the others. We have no idea what this is for, we may never know because we lack the intellect to understand it – something posed in the article.

    Note you’re also using human level intellect, biases, biology, motivations, metrics, etc. to determine value/ intelligence of another species. Again, none of us may be in a position to actually understand at all, not unless we undergo the 40 million or so years evolution that cetaceans have to bring us to their level.

    I really recommend the article, it’s very good!

  • Rob Henry July 4, 2015, 3:45

    Curtis, you have opened up a huge topic, and this isn’t the forum on which to give a reply that would do it justice, so let me be curt at the expense of oversimplification.

    Many decades ago, the scientific (animal) psychometric community split in two, with little communication between those two branches today. One group believed that animals would display intelligence in such different ways that it was almost impossible to rank them against each other. The others that there would be plenty of crossover and a universal g-factor. We now know that second view is at least true for primates.

    True, cetaceans brain structure is superior to primates is some ways, however it is deficient in others, eg missing an entire layer of the neocortex and, even more importantly, having a lower neuron number density and characteristic density scaling rule with increasing brain volume.

    PS: if it wasn’t for the abovementioned psychometric divide I believe that sperm whales would have been identified long ago as warranting further investigation – as such I can hardly have any sympathy for that first view.

  • Dan July 6, 2015, 2:52

    1) An all out nuclear war would not be the end of mankind, no matter if its now or in 1962. The world is much bigger than you think. For every big city nuked to rubble there would be ten smaller cities that do not get hit at all.

    2) Only nuclear ground bursts leave craters. The only targets that warrants a blast-wave effect reducing ground burst are supearheavy armored targets like nuclear silos or command bunkers. These are quite few compared to the number of warheads and are located well away from civilian installations.

    In a nuclear war the vast majority of nuclear detonations would be high altitude detonations that leave little fallout (none local) and no ground crater. These kind of detonations maximize the power transfer from nuclear fireball to devastating blast wave. Your speculation would be more interesting if you knew something about nuclear warfare. Its not rocket science but mostly about game theory and basic accounting.

  • ljk July 7, 2015, 10:53

    Reading this interview makes me think that as some people get older, they get less adventurous and just want to stay home.


  • ljk July 7, 2015, 12:52


    SETI and the Rise of the Machines

    Non-biological intelligence offers another possible solution to the Fermi Paradox.

    By Dirk Schulze-Makuch


    JULY 6, 2015 4:06 PM

    At the recent Astrobiology Science Conference in Chicago, Seth Shostak of the SETI Institute made the intriguing point that intelligent extraterrestrial beings are more likely to be machines—or Artificial General Intelligence (AGI)— than biological organisms.

    This perspective might help us answer Enrico Fermi’s challenging question about extraterrestrials: Why haven’t we seen them already? Even if only a small fraction of habitable planets give rise to life, the number of inhabited planets could number billions in our galaxy alone. Assuming a fraction of them develop technology, the number of civilizations should still be considerable. But maybe the span during which technologically advanced life forms remain biological represents only a blip in time.

    Shostak explained that machines evolve much faster than humans or other biological life forms; artificial intelligence researchers predict that AGI will overtake the human species within the next 20 to 50 years. To appreciate the fast rise of machines, remember that the first computer was invented in 1945.

    Whether computers and artificial intelligence can evolve on their own, and perhaps even become conscious, is controversial. Other scientists argue that machines can become only as smart as their designers. However, if we accept Shostak’s argument, the lifetime of a technologically advanced life form based on biology is indeed extremely short, since it will quickly be overtaken by artificial intelligence.

    This, in turn, affects our search for intelligent life in the universe. Since most technologically advanced civilizations would be machine-based, it appears we have focused our SETI efforts on the wrong targets. Instead of searching for wet Earth-like planets, we might look elsewhere. AGI, for example, might prefer to settle close to large energy sources such as O-stars and black holes. Figuring out the intent and objectives of the AGI will be more difficult than it would be for biological life forms. Shostak speculated that they might be interested in computer simulations of their ancestors, changing parameters of the universe, or just gathering information from afar.

    Would they contact us? And if not, how could we find them? They may not have gotten in touch with us because we haven’t yet passed the threshold to become an Artificial General Intelligence. In that case, the only way to pick up a signal would be to accidentally intercept one that was meant to communicate with an AGI’s “peers.”

    Such a scenario was proposed at the same meeting by William Bains of the Massachusetts Institute of Technology, as an explanation for the famous Wow! signal detected by the Big Ear radio telescope in 1977. The signal showed the expected hallmarks of a signal originating from outside our solar system, but was received only once.

    Still, as Shostak admitted, his was “a very speculative talk.” And so is any interpretation of the Wow! signal.

  • Marshall Eubanks July 7, 2015, 13:23

    1.) Intelligent machines (or, for that matter, unintelligent but replicating machines) would also be biological organisms (albeit, not carbon based ones). You can’t escape evolution by changing your operating system or your substrate. Silicon based life (for that is what it would be, unless it was a silicon-carbon mixture of some sort, which I regard as more likely) would be subject to Darwinian principles, as are we all. (Even perfect and unvarying replication is from a Darwinian just another play option, and probably not a very good one over, say, a billion year time horizon.)

    2.) From a statistical perspective: from what we know, carbon biologies : ~3 billion years+, silicon biologies, 0. Bayesians would bet on carbon