We are living in interesting times. Indeed, the problems facing our civilization seem so overwhelming that talking of space exploration appears frivolous or even ideologically suspect. There is a common attitude that such endeavours divert attention from mankind's 'real' problems and are a waste of valuable resources. However, as I hope to show, although problems of current concern may be all too real, they are small when looked at from a perspective appropriate to activity beyond this planet. Far from being a waste of resources, such activity is perhaps the only form of high energy consumption of long term value.
Critics argue that space exploration is itself damaging to the environment [1], or more subtly, is inextricably bound up with a socio-political and economic system and a philosophy which are ecologically unsound. However, I will argue that concern for the environment and the space effort are in fact complementary.
A less tangible fear arises from the persistence of a deep rooted superstition concerning hubris. By hubris is meant the arrogant pride that comes before a fall. Thus there is a fear that any attempt on Man's part to overstep his natural bounds (however we seek to define them) will lead to some form of retribution. In venturing into space Man is getting above his natural station - literally. However, I wish to evoke another equally ancient idea - the myth that Man's place in nature is not fixed, the myth that despite our terrestrial origins we may rise through the heavenly spheres and know our cosmic destiny as citizens of the universe.
Various reasons have been given to justify what is a risky and expensive enterprise, promising no immediate rewards. The supposed benefits popularly advanced for the space effort change in accordance with what is considered ideologically sound. It is a symbol of national identity - until the identity changes. It is a vindication of a perfect social system - until that system collapses. It is the space race, a strategic necessity in a conflict with another super-power - until there is no other super- power to compete with. It is a natural extension of economic growth - until the desirability or even the possibility of unlimited growth is questioned. Now the role of satellites as sentinels monitoring man-made threats to the biosphere is stressed in accordance with current preoccupations [2] (it could be mentioned in passing that similar justifications have been felt necessary for mountaineering, polar and undersea exploration, scientific research, philosophical speculation and religion).
There may be an economic spin-off from the space programme. It may even have social benefits - any civilization requires some large, collective endeavour and space colonization is the only such endeavour appropriate to a global civilization. But underlying these rationalizations is our desire to be more than what we are, our insatiable curiosity and a deep need to find our true place within the greater scheme of things.
This quest is as old as the Human species. However, analogies with previous events in our own recent history are insufficient to provide a meaningful context for space exploration. Therefore it is on the broader, biological implications that I wish to focus, placing it in its evolutionary context.
The space programme is of evolutionary significance, since for the first time the biosphere has produced living beings which have left the planet to view it and its surroundings from outside. This evolutionary breakthrough was first made by dogs, chimpanzees, guinea-pigs, mice and frogs, although humans got there as well eventually [3] (it is worth mentioning in passing that the ability to form an image of oneself seems a prerequisite for this development of normal human consciousness. It is interesting to speculate on what effect the availability of such a self image will have on global culture and the biosphere as a whole).
The most obvious biological principle at work here is the tendency for living creatures to explore and gather information from their environment. Viewing from our present cultural perspective it is tempting to make comparisons with previous great voyages of discovery. However, most historical voyages were not mankind entering a new environment, but one culture encountering another. It is a suitable irony that this year's celebration of Columbus's discovery of an already inhabited continent should be marked by a hundred million dollar initiative to search for extra-terrestrial intelligence. The visit to the moon in 1969 was the first major voyage of discovery in which Man as a whole moved into a new environment, rather than re-uniting isolated groups of our own species. Perhaps it is the second time if we count the initial dispersal of Homo Sapiens when we evolved some two million years ago - a dispersal that may one day be repeated on a vastly larger scale.
This is of course assuming that Man will be able to colonize space. Again it is tempting to seek analogies with previous colonial expansions in human history. Thus for the United States of America space is the 'high frontier' by analogy with its own recent past. Again the analogy is misleading since most recent human migrations were into already inhabited areas.
A more plausible analogy is with the colonization of the Pacific by the ancestors of the present day Polynesian islanders. Their initial island-hopping is thought to have created a culture prepared to risk deep-sea voyages of increasing duration. This is seen by some as a model of how the planets of our solar system may provide 'stepping stones to the stars'. [4]
At any rate, we are rapidly reaching the point where there is no more fertile land area left on the planet to colonize (indeed, this is one definition of global civilization). Thus to the more optimistic futurologists space is infinite living space, permitting unlimited human proliferation. Although such mass migration off the planet may be possible in the distant future [5], present technology is totally inadequate to relieve current population pressure (this does not of course imply that population pressure will not be a motivating force in space colonization).
The urge to grow is of course common to all life. There seems to be evidence of it all around us. However, the biosphere as a whole has not grown appreciably for some considerable time (since the colonization of land in fact). This is for the simple reason that it now comprises every part of the planet's surface where life is possible. When considering the biosphere as a whole, local examples of apparent growth are merely replenishment of existing structure, or in the case of succession, repairing damaged areas. Indeed, some would argue that, due to human mismanagement, the biosphere is shrinking - not only qualitatively in terms of extinction of species, but also quantitatively in terms of geographical area, biomass and productivity. At any rate, the colonization of space would provide the first opportunity for the biosphere to actually grow since it first became a sphere.
One could ask at this point whether an increase in size is true growth if it is at the expense of a reduction in functional integrity of the whole system. Growth is a deceptively simple concept. Perhaps it would be useful at this point to distinguish between growth, expansion and proliferation.
Expansion is simply increase in size, as in the expansion of living cells by absorbing water (seen most dramatically in the sudden apparent growth of fungal fruiting bodies). Human activity beyond the planet's atmosphere seems unlikely in the near future to produce any significant increase in the size of the biosphere (since I don't come from an engineering background, I wouldn't presume to speculate on the eventual feasibility of dismantling asteroids and assembling them into a 'Dyson Sphere' around the sun [6]). This is of course measuring the biosphere in terms of the total mass of living matter. The ecosphere (in the sense of the total space in which the activities of life take place) would be vastly extended by even a single lunar base.
As well as growing in size, living things are capable of making copies of themselves. At the cellular level this is by internal division (combined with expansion to maintain cell size). The explosive population growth of microorganisms is a striking example of this.
This proliferation of structural units is an expression of the replication of the information content of the cell. A characteristic of information is that it is not confined to any particular type of hardware. The primary storage medium common to all terrestrial life forms is the complex molecule DNA. However, this storage system has now been complemented by learnt behaviour patterns and language. The latter has enabled the cultural transmission of ideas that has made space exploration possible.
Since information is not limited to any one medium, organic, carbon-based structures may not be the only way of replicating information. Silicon (an element in the same chemical group as carbon) has often been suggested as an alternative basis for life. Of course, silicon-based information processors already exist in the form of computers. Some see these as a potentially superior form of life more fitted for colonizing the galaxy than their outmoded carbon technology precursors. It has even been argued that the fact that our own planet has not been taken over by robot colonists from other solar systems implies the absence of other, more advanced civilizations in the galaxy [7] (puny earthlings struggling to communicate with computer 'assisted' bureaucracies could be forgiven for assuming that the malevolent alien intelligence is here already).
All this is based on the acceptance of the current notion that the essence of life resides in the programming of the cellular computer and that mind and consciousness is a property of the software of the nervous system. This notion has some rather interesting implications. The contents of the collective human psyche have been beamed into outer space for some decades in the form of radio waves. This has now been complemented by television broadcasting.
Now broadcasting is a term originally applied to sowing seeds - small packets of genetic information. What if our electromagnetic seeds fall on fertile ground? If all the information we are broadcasting into space encounters a suitable storage medium, capable of replicating it, then ideas we think of as essentially human will continue to live and grow throughout the galaxy, long after the organic hardware that originally processed them has ceased to be replicated. Thus the best way to colonize space may be to watch lots of television. Imaginary characters currently starring in various soap operas may, millions of years hence, form the seeds of identity for the mighty beings who will rule the universe.
Proliferation, whether it be of cells or ideas, involves the replication of a basic unit or units, thus increasing the size of the total set. Growth implies more than this. It implies the differentiation of structure and function amongst the proliferating elements, and their organization to form a single, coherent body. Whilst proliferation is limited only by environmental stresses, growth may be inherently finite. The human body itself is an obvious example of finite growth.
When a body reaches maturity it may stop growing, but it may start doing something else. It may reproduce. That is, make a copy of itself. This is, of course, replication again, only on a larger scale. Some biologists have seen space exploration as significant in that it enables for the first time the biosphere as a whole to reproduce itself. In seeing humanity as the eye (or even I) of the universe, philosophers are perhaps being too high-minded. A number of more apt metaphors suggest themselves. The most polite way of putting it is to say that through space exploration we may act as the midwives of Gaia. [8]
Of course, this midwife analogy is rather inaccurate, since mammal reproduction is sexual. By contrast, the biosphere making a copy of itself external to the planet is an asexual process, resulting in identical clones (the term 'identical' needs some qualification, since it assumes that the biosphere can be replicated with no substantial loss or corruption of essential information).
Sexual reproduction would require interaction between at least two types of space colony (or perhaps between the mother biosphere and one of its own offspring). The two biospheres would also have had to have diverged. Doubtless, many theoretical objections would be found for discouraging intercourse on such a scale. It would be feared that such a process may threaten the existing integrity of the systems involved. It is often assumed that this is the price paid for an increase in variety - the creation of new potential. However, recently a less disturbing view of sex has arisen, enabling it to be comfortably accommodated within the body of current theory. Sex, it is believed, originated as a repair mechanism to preserve existing information. In the formation of new copies two alternative sets are available - thus corrupt segments of information in one set can be compensated for by the equivalent segment of the other set. [9] The existence of off-planet colonies would enable such reciprocal-maintenance to occur on a vast scale.
The problem with the analogy with reproduction is that it assumes that the biosphere acts like a single organism - a debatable assumption. Ecosystems do not reproduce as a single unit, but arise as assemblages of individually reproducing beings sharing the same environment (in the biosphere which comprises all ecosystems the shared environment is, of course, the planet). We have now moved out of that shared environment. In exploring space we are moving into an entirely new sphere. From a biological stand-point this shift is of at least the same magnitude as the first colonization of land by life-forms originating in the sea. That is why I term space exploration an evolutionary event. As with the shift from sea to land, it is a shift into a harsher environment, less conducive to life. As yet humans cannot reproduce in space, so must return to earth to breed, in that sense we are analogous to amphibians which must return to water to complete their life cycle.
Some would argue that the analogy with the evolution of life on land is not entirely accurate since this is presumed to have resulted from natural selection acting on aquatic creatures that found themselves accidentally isolated from their familiar environment. On the other hand, it is assumed that space exploration arises from choices made by intelligent individuals. Looked at against the yardstick of Mankind as a whole however, the space effort to date seems similarly accidental, arising as a by- product of the natural processes of national aggrandizement, economic competition and squabbles between groups of individuals. For the colonization of space to be a conscious decision on the part of Mankind as a whole it would have to be the act of a global civilization with motivations appropriate to its own level of organization.
Another apparent difference between space exploration and the colonization of land is that the latter was not just a behavioural adaptation, but a process of transformation resulting from the arising of mutant forms. If the colonization of space is of equal or even greater magnitude it will require some form of transformation within the organisms involved. We could speculate on what form the future mutants might take (we are talking here about human mutants - other terrestrial organisms such as bacteria already possess a degree of pre-adaptation to extra-terrestrial conditions hard to explain given current assumptions about life's origins [10]). What selection pressures would be exerted on us by the cold, low-pressure, low-gravity, high-radiation environment? Highly sociable, thick-skinned, non-smoking blobs with a liking for computer games seem one possible outcome. It is perhaps best not to speculate too much in this direction since any culture needs to be inspired by images of potential self which are heroic rather than realistic. In any case, the selection pressures on future spacefarers are likely to be artificial rather than natural. By artificial I don't mean genetic engineering (eugenics is now thoroughly discredited). Rather the rigourous processes of selection [11] will be an intensified version of those that now face any applicant for the job of road-sweeper in many countries. Space colonies will provide a useful preview of the effects of limiting a naturally varied species to an ideal psycho-physical profile designed by a committee of experts.
An even more disturbing idea is that the mutations necessary for humanity's move into space may have already occurred. The development of language enables for the first time on the planet a non-genetic form of heredity. Even more radical is the development of the silicon chip and information-handling systems not based on carbon technology. This is a much greater evolutionary jump than the minor modifications of an existing DNA-coded structure necessary for land life. The development of language and culture is not necessary to live successfully within the biosphere (many environmentalists seem to think they are a handicap). They may however be a pre-adaptation to life outside it.
I say life outside it since there is nowhere else in the solar system conducive to human life. Establishing a colony off-planet is therefore less like adapting to a new environment than constructing one. This is the human urge to control and manipulate the environment raised to the nth degree. Not content with small, self-contained lunar colonies, some scientists envisage modifying entire planets to make them suitable for terrestrial-type life [12] - a process for which the term 'terraforming' has been coined. This would be a transition to what the Russian astronomer Kardashev terms a phase 2 civilization, drawing on the resources of an entire solar-system rather than a single planet (phase 3 civilizations operate on a galactic scale).
This increasing manipulation of the environment can be seen as a self-reinforcing process of 'externalization' in which internal features of the human (or equivalent) organism are amplified by technology. In our own particular case the power of muscles is amplified by tools and the principles of human movement externalized in machines. The information processing and the capacity for self-regulation fundamental to life are externalized in computers and automated systems.
Such an attitude may strike some as being slightly out of step with current concern over Man's impact on the environment. It seems yet another example of the aberrant nature of human behaviour. However, all organisms control their environment to a greater or lesser extent. One could cite numerous examples from simple birds' nests to air-conditioned termite colonies and the building of huge coral reefs. According to the Gaia hypothesis, [13] life as a whole does not simply adapt to the requirements of the planet on which it finds itself, but constructs and maintains its own environment. So terraforming entire planets is perhaps not a new idea after all, but something that life has done before, and with human assistance, may do again, thus spreading Gaia beyond the present biosphere.
The outward thrust of Man's endeavour and a respect for Mother Earth may seem strange bedfellows. However, the gaian view of the biosphere has its origins within the space program, and concern for the living world and space exploration are complementary. We probably already have the technology to build a permanently manned lunar base. However, to establish a self-sufficient colony requires a revolution in our understanding of ecological systems. This is not just a theoretical understanding, but an internalization of ecological principles. Thus the process of 'externalization' through technology must be complemented by the continuation of a much older process of 'internalization' (one must say 'older', since the universe as an externalization arising through the manipulations of a vast being is viewed by contemporary intelligentsia as a passing human fancy).
To return to an earlier phase of evolution, the colonization of land by sea creatures was only made possible by internalizing the marine environment. The blood of land-living animals provides a substitute for the sea from which they came. The invention of the cleidoic egg with its own 'private pond' enabled organisms not only to forage on land, but also to develop there. The penetration of the new environment was facilitated by the evolutionary breakthrough of the penis. The development of copulatory organs enabled the internalization of reproduction which was formerly dependent on an external aquatic environment. The self-regulation of temperature by behavioural adaptations or physiological mechanisms enabled animals to thrive outside the protective buffering of water. Of course, in a space colony this principle would be taken a stage further by the regulation of atmosphere as well. Greenhouses, air-conditioned offices, submarines and polar research stations are all developments in this general direction. [14] The most ambitious project to date began last year with the opening (or rather closing) of Biosphere Two with its 1.2 hectares of artificial ecosystems.
As well as the eight human biospherians there are some four thousand species in this glass bubble in the Arizona desert. Like the colonization of land from the sea, the colonization of space from the earth will be an experiment in symbiosis. A crucial question here is - how big does such an enclosure have to be to be viable? This problem is addressed in a myth from an earlier phase of our evolution. (It is of a type typical of organisms adapted to exposed areas of a planet whose surface is largely water covered. However, there are resonances with a deeper archetypal level). Like our own contemporary spacefarers, the myth's hero is preoccupied initially with engineering problems. However, it soon becomes apparent that survival outside the familiar environment depends as much on biological knowledge as on technology. Noah's common sense would no doubt tell him to build a gene bank of all life forms used in his everyday life. However, he was also specifically instructed to include minimal viable populations of organisms not directly utilized by his particular culture. The key issue here is the, as yet obscure, link between biodiversity, complexity and ecosystem stability. [15]
Of course, in addition to interspecific relationships the spacefarer must also consider far more variables in the physical environment than the optimum amount of water for human physiology. Here the analogy of space colonization with the evolution of land organisms breaks down. In the move to land it is not the complete environment that is internalized, but only that aspect of it provided by the watery component. There was after all a pre- existing atmosphere and some free water already present on land (thus while there was increasing manipulation of the surroundings, the total externalization of the organism's own internal powers of organization in a self-created environment was unnecessary).
A space colony is, by way of contrast, a complete move out of the biosphere - or is it? The biosphere is not limited to this planet. The most obvious extra-terrestrial component is the energy source - a star eight light minutes away. This provides not only the energy required for synthesizing organic compounds, but also powers the biogeochemical cycles that form the metabolism of the biosphere (a complete 'internalization' of the biosphere would therefore require a space colony that contained not only all the species required for a self-regulating system, but also its own nuclear fusion reactor to power it. Thus externalizing the processes of our own atomic structure).
Not only does an extra-terrestrial energy source provide the energy for the biosphere, but the biosphere's structure is also shaped by the earth's reception of that energy (the simplest example being the different categories of ecosystem dependent on the angle of incoming solar radiation at different latitudes). When we reflect on what modern science tells us about our place in the universe we see that we are already participants in a greater world than the world which orbits our sun.
This apparent leap of the imagination is reinforced by a knowledge inherent in basic physical perception. The material basis of our consciousness of the world is the brain's interaction with its environment. On a cloudless night the physical correlate of perceiving a star is therefore not a little man inside an isolated skull, but a physical system light years in diameter (and a process acting over aeons of time). If one accepts this ecological view of mind, it follows that any attempt to construct a meaningful philosophy of our place in nature, must at the very least accord with the sense-base. Since our planet is a mere eight thousand miles in diameter any attempt, however well meaning, to make concern with the earth alone the context of human aspiration is doomed to failure. In the long term few human beings would be prepared to worship a god (or goddess) smaller than their own field of consciousness.
Of course, in normal terrestrial consciousness mind arises as we act on that which we perceive. In the space programme this two-way flow of information is extended further in feed-back loops beyond the planet's surface. However, one could argue that it is not necessary to go out into space physically, since we are already participating in the life of a world beyond the earth. Even when minding our own terrestrial business the rhythms of our common life are tuned to events occurring at the solar system level. The alternation of day and night as the earth spins on its axis and the round of the seasons as the planet orbits the sun are perhaps too obvious to mention. Other, subtler rhythms are the fluctuations in sun-spot activity and the Saros Cycle governing the tides.
There is a paradox here. The astronomical events producing such cycles and the physical mechanisms of our response to them are becoming increasingly understood. However, the increasing artificiality of modern life means that we are becoming less attuned, or even aware, of such rhythms. Is our isolation from natural rhythms a necessary prerequisite for space colonization, freeing us from reliance on change perceived from a geocentric stand-point? Or are we so conditioned by our terrestrial history that we will have to re-create some of those rhythms artificially?
These rhythms give us our collective sense of security and continuity (so much so that life outside them seems as unwise and 'unnatural' as life in altered gravity). However, as we move to progressively larger time scales that sense of security is threatened. Continental drift may re-arrange our planet's surface, but at least the process is slow on human timescales. Difficulty in predicting ice-ages is more unsettling. Even worse, the evidence of the fossil record indicates that the history of life on the planet is punctuated by periods of mass extinction. [16] Possible causes range from the terrestrial (volcanic activity) to solar system events (impact from meteorites) to events on a galactic scale (stars exploding as supernovae).
The potential threat from meteorite impact is something that has been in the news recently (occasioned by the return of the comet Swift-Tuttle). It has been suggested that through the space programme humankind may act as a sentinel, protecting the biosphere from external threats to its integrity [17] (the myth of Noah's ark also returns to mind). This puts space exploration in rather a different perspective. Curiously, while there is much popular concern over man-made threats to the biosphere, there is less interest in dealing with external threats. Presumably, this is because ecological self-destruction is a final vindication of our own power and importance, whereas being the potential innocent (and therefore inconsequential) victim of a cosmic accident is just too humiliating to contemplate.
We may learn to live in harmony with mother earth, but what of that greater nature, to whose laws both Man and the biosphere are subject? Does she present a kindly, cruel or insouciant face? Like all organisms we have an instinct for survival, but our behaviour has evolved as an adaptation to limited terrestrial conditions. Organisms can adopt one of three broad survival strategies, success depending on how they match local conditions within the biosphere. [18] If the environment is stable and resource- rich then an aggressive, competitive approach will be most successful. Where resources are scarce this strategy of unlimited growth leads to extinction. Long term survival here depends on careful budgeting of what few resources are available. In an environment subject to sudden, catastrophic change neither strategy is successful. To survive in such circumstances requires the investment of resources in small structures that can either survive the catastrophe or colonize other areas.
The question now arises as to what sort of environment the earth as a whole inhabits, and therefore what sort of survival strategy is appropriate to a global civilization? In the early stages of industrial culture it was assumed that the earth was resource-rich and stable. Now the stress-toleration strategy seems to be gaining popularity. Such a strategy would have no place for extravagant deployment of resources in an unnecessary adventure in space. However, if as the geological and astronomical evidence suggests, the wider environment in which the biosphere exists is one of occasional violent change, then either of the first two strategies would lead to extinction. Extinction of Homo Sapiens that is, but not necessarily of life, even intelligent life. On the basis of available evidence life appears to have been remarkably resilient. Humanity could evolve again from any remaining animal group (using the term 'Humanity' in the same broad sense we use the term 'tree' - to indicate a similar adaptation to the same type of ecological niche arising in a number of different groups by convergent evolution). The dinosaurs for example once had representatives that had evolved sufficient intelligence for co-operative hunting and parental care of young. Given sufficient time one species would no doubt have developed an advanced technological civilization. However, a planet-wide catastrophe (or series of catastrophes) removed them from the scene before they could develop space flight.
The science-fiction monsters we have already populated space with in our collective imagination are usually dismissed as psychological projections of ourselves. However, such dreams may arise from a subliminal perception of something else. Alien intelligence is here already, at least in potential. It evolved with us and waits its opportunity to claim its inheritance, as our ancestors claimed ours two million years ago. If Homo Sapiens decides not to fulfil its extra-terrestrial destiny, then hopefully our increasing interest in conservation will at least insure that there are sufficient resources left to get our eventual replacements off the planet (also assuming we have left sufficient biodiversity for a speedy restoration of the biosphere following the next natural mass extinction).
It is of course possible that we may never be able to fully escape the prison of our planet. Or if we do go we may be so changed as to become no longer human as we now recognize it. The universe itself may not be able to support life indefinitely. Paradoxically, it is only when the inhumanity of the universe is grasped that true compassion may arise - a real reverence for all life, unclouded by sentimentality. When a culture faces such issues it also raises a problem of motivation (the only analogy available to us at this point is the crisis experienced when we face our individual mortality). Being forced to consider things on a scale where our normal motives appear irrelevant creates a vacuum. This psychological gap is likely to be as great a barrier to an intelligence spreading through the galaxy as are the immense stretches of time and space that separate the worlds of our universe.
The mentality of beings who have proved able to cross this invisible barrier is as mysterious to our present selves as the depths of space itself. For Homo Sapiens to make the crossing seems to require something we can only call faith. Faith is normally associated with an apparent self-confidence, but this faith cannot be faith in Man as we currently perceive ourselves, or any of the gods we make in that image (one must become an unidentified flying object).
Perhaps this faith is connected with a realization that the something greater to which we aspire is in a sense already part of us. Whatever the origin of the universe as a whole, there seems to be growing evidence that life or some of its precursors originated in processes greater than those of our planet. My analogy with the colonization of land did not utilize the full story. Having colonized land, life evolved more complex organisms, some of which returned to the sea. If life is a cosmic phenomenon, then in our tentative exploration of the space around us we may be more analogous to seals and walruses than amphibians. Perhaps we are not leaving home, but returning there?
This page, and all contents, are Copyright (C) 1995 by Saros. The material may be used freely providing the source is acknowledged.