Mars, at a greater distance from the sun and a smaller size than Earth, must have cooled further than our planet. Martian animal life must therefore be more advanced than
Homo sapiens.
For all our vaunted wealth and technology, what have we built that a telescopic observer on Mars might recognize as a product of
advanced life? The Great Wall of China? Our largest cities? Nothing, in any case, to match the scale of the Martian canals:
Nor is this outcome [evolution to higher complexity] in any sense a circumstance accidental to the earth; it is an inevitable phase in the evolution of organisms. As the organism develops brain it is able to circumvent the adversities of condition; and by overcoming more
pronounced inhospitality of environment not only to survive but spread. Evidence of this thought will be stamped more and more visibly upon the face of its habitat. On earth, for all our pride of intellect, we have not yet progressed very far from the lowly state that leaves no records of itself.
In particular, the increasing harshness of Martian environments implies a mental response from
evolving life:
In an aging world where the conditions of life have grown more difficult, mentality must characterize more and more of its beings in order for them to survive, and would in consequence tend to be evolved. To find, therefore, upon Mars highly intelligent life is what the planet’s state would lead one to expect.
Put together all these conjectures and inferences—that Mars has
vegetation; that plants imply animals; that both plant and animal life must progress to greater complexity; that planetary cooling and increasingly more challenging environments inspire evolutionary progress; that Mars has cooled further than Earth; that beings more advanced than
Homo sapiens
must therefore inhabit Mars—and the supposed canals cry out for interpretation as technological devices
for husbanding the depleting resources of a cooling and drying planet.
Schiaparelli’s “channels” must really represent what his Italian word conveys in English—true canals of planetary scale, built by higher creatures to tap the only available supply of water:
Dearth of water is the key to their character . . . So far as we can see the only available water is what comes from the semi-annual
melting at one or the other [polar] cap of the snow accumulated there during the previous winter. Beyond this there is none except for what may be present in the air. Now, water is absolutely essential to all forms of life; no organism can exist without it. But as a planet ages, it loses its oceans . . . and gradually its whole water supply. Life upon its surface is confronted by a growing scarcity
. . . [The canals are], then, a system whose end and aim is the tapping of the snow-cap for the water there semiannually let loose; then to distribute it over the planet’s face . . . From the fact, therefore, that the reticulated canal system is an elaborate entity embracing the whole planet from one pole to the other, we have not only proof of the worldwide sagacity of its builders, but a very
suggestive side-light, to the fact that only a universal necessity such as water could well be its underlying cause.
We should admire, Lowell suggests, not only the high intelligence that could build such a system, but also the superior moral qualities of beings that can cooperate (as we seem so singularly unable to do) at a planetary scale! “The first thing that is forced on us in conclusion
is the necessarily intelligent and non-bellicose character of the community which could thus act as a unit throughout its globe.”
Martian civilization may be doomed, despite this grand and noble planetary attempt to ward off disaster. But at least we may take courage and comfort in higher evolutionary stages thus implied for future earthly life (while we may hope for a different outcome):
One of the things that makes Mars of such transcendent interest to man is the foresight it affords of the course earthly evolution is to pursue. On our own world we are able only to study our present and our past; in Mars we are able to glimpse, in some sort, our future. Different as the course of life on the two planets undoubtedly has been, the one helps, however imperfectly, to better understanding
of the other.
Lowell’s fanciful theory unleashed a worldwide flood of excitement and commentary, most negative (although the nonexistence of Martian canals was not conclusively established until the Mariner satellites photographed the Martian surface at close range in the 1960s. I well remember the journalistic “hook” that Lowell’s old theory still provided; the popular press treated the Mariner
expedition largely as a test for the existence of canals. As a young space enthusiast, I was disappointed, though not at all surprised, by the negative result!)
Alfred Russel Wallace was still alive and active when Lowell published his book on Martian canals—and still wielding his pen for a living. (Darwin and his friends, partially from guilt at their good fortune of inherited wealth, had secured
an annual governmental pension for Wallace, but not nearly enough for a scholarly life free from financial worry.) Wallace, who had long been interested in the possibility of extraterrestrial life, and who had developed his own distinctive and idiosyncratic argument for earthly humanity as the universe’s only example of higher intelligence in bodily form, wrote an entire book to refute Lowell’s
theory of canals (
Is Mars Habitable?
[London: Macmillan, 1907]).
Wallace mistakenly accepted the existence of canals and attempted to supply a purely physical explanation—as cracks “produced by the contraction of heated outward crust upon a cold, and therefore non-contracting interior.” Nonetheless, he offered a devastating critique of Lowell’s biological interpretation:
The one great feature
of Mars which led Mr. Lowell to adopt the view of its being inhabited by a race of highly intelligent beings . . . is that of the so-called “canals”—their straightness, their enormous length, their great abundance, and their extension over the planet’s whole surface from one polar snow-cap to the other. The very immensity of this system, and its constant growth and extension during fifteen years
of persistent observations, have so completely taken possession of his mind, that, after a very hasty glance at analogous facts and possibilities, he has declared them to be “non-natural,”—therefore to be works of art—therefore to necessitate the presence of highly intelligent beings who have designed and constructed them. This idea has colored or governed all his writings on the subject. The innumerable
difficulties which it raises have been either ignored, or brushed aside on the flimsiest evidence. As examples, he never even discussed the totally inadequate water-supply for such world-wide irrigation, or the extreme irrationality of constructing so vast a canal-system the waste from which, by evaporation, when exposed to such desert conditions as he himself describes, would use up ten
times the probable supply . . . The mere attempt to use open canals for such a purpose shows complete ignorance and stupidity in these alleged very superior beings; while it is certain that, long before half of them [the canals] were completed their failure to be of any use would have led any rational beings to cease constructing them.
Recent reports of fossil evidence for life in a Martian
meteorite inspired me to retrieve the volumes of Lowell and Wallace from my bookshelf (where I had shelved them side by side—for history, among its many ironies, often places enemies in life into invariable positions of posthumous conjunction). These putative organisms of bacterial grade could not be more different from Lowell’s wise canal builders, but I was struck by a common error that both invalidates
Lowell’s argument as presented above, and also underlies the fallacious main reason for public fascination with the current claim.
On August 7, 1996, NASA (the National Aeronautics and Space Administration) held a press conference to announce the publication, in the forthcoming August 16 issue of
Science
magazine, of a paper by David S. McKay and eight additional colleagues titled “Search for
Past Life on Mars: Possible Relic Biogenic Activity in Martian Meteorite ALH84001.” In short, these scientists argued that one of the dozen known meteorites from Mars (as reliably inferred from chemical “signatures” matching Martian atmospheric and surface conditions) contained signs of life preserved in carbonate materials deposited within cracks in the rock. These cracks presumably formed and filled
on Mars some 3.6 billion years ago. (The rock was dislodged by an asteroidal impact on Mars some 15 million years ago and eventually fell on an Antarctic ice field about thirteen thousand years ago.)
The controversial evidence for life does not feature such “hard” data as a shell or a bone, but consists of chemical signals in the form of isotopic ratios and mineral precipitates often formed by
biological activity (but explainable in other ways), and also of minute rod- and hairlike objects looking vaguely like the smallest of earthly bacteria, but also easily interpreted as inorganic in origin. As a betting man, I would not risk any money on the case, but neither, by any means, do I dismiss the idea. The article by McKay and colleagues is a model of caution and good sense, and their case
is certainly plausible for two reasons not widely enough appreciated: first, that Mars featured appropriate conditions of running water and denser atmosphere during the first billion years of its history (when the cracks of the meteorite filled with carbonate material); second, that the Earth, at the same time and under similar conditions,
did
evolve life of bacterial grade.
The news created
the greatest flourish of public interest in a scientific topic since the eruption of Mount St. Helens. Headlines captured the front page of nearly all major newspapers.
Time
magazine publicly wondered whether Mars or the nomination of Dole and Kemp at the Republican convention should command the cover. They editorialized: “One of the worst things for a news magazine is a long drought of news.
Almost as challenging is being hit with two stories the same week.” (They opted for the living men rather than the putative fossil bacteria, and Mars only got a corner flap of the cover, right above Jack Kemp’s head.) More locally, my phone message tape filled in less than two hours with twenty-five calls from journalists.
Our leaders erupted into rapture. Bill Clinton, with a wicked sense of
timing, and hoping to steal some cosmic thunder as the Republican convention opened, held a quick press conference to proclaim: “Today Rock 84001 speaks to us across all those billions of years and millions of miles.” My dear friend Carl Sagan, who died just four months later, enthused from a hospital bed: “If the results are verified, it is a turning point in human history, suggesting that life
exists not just on two planets in one paltry solar system but throughout this magnificent universe.”
A week later in our culture of sound bites and momentary celebrity, the story disappeared from public view. Invisibility quickly descended over a discovery that many commentators had anointed as the greatest scientific revolution since Copernicus and Darwin! Lord Byron spoke in
Childe Harold
about
a “schoolboy’s tale, the wonder of an hour!” But Andy Warhol certainly placed his arty finger on the pulse of modern life by quartering the moment of attention to fifteen minutes, while extending the opportunity to everyone in an age without standards—from Kato Kaelin to poor Mr. Bobbitt, quickly cut off in more than one way.
But then, on second thought, maybe the story deserved no “legs,” and
died a proper death for lack of proof and new material to sustain the news-mongers. I would like to take an intermediate position and argue that public fascination rested largely on a false premise that guaranteed an early oblivion for the story—but that a proper formulation should sustain both interest and hope for years to come.
Lowell’s logic for inferring the necessary existence of “Little
Green Men” from supposed evidence of “lowly” plant life contains many errors, but none so central, or so persistent today, as the assumption that life at simplest grade must, once evolved, necessarily advance toward greater complexity and eventual consciousness. For, in such a formulation, the origin of life in
any
form implies the eventual evolution of complex creatures with consciousness, so
long as planetary environments remain hospitable. Thus, Lowell argued, the origin of simple vegetation unleashes a process that must lead to canal builders. Finding the “lowest” can almost be equated with guaranteeing the “highest.”
Over and over again, particularly on radio call-in programs and newspaper “man [and woman] in the street” columns, fascinated members of the public made the same
mistake: if any kind of life, no matter how simple, had arisen on another world, then the evolution of consciousness must be part of a predictable natural order. (Mars became dry and frozen, thus halting the process at bacterial grade on our neighboring world. But the sequence must run to completion in many other places—for once we know that life can evolve
at all
on other planets, then Little
Green Men must pervade the universe.)
The leading article in
Time
magazine began with this erroneous premise, made even worse by a false dichotomy that contrasted this supposedly inevitable scientific inference with a theological alternative:
The discovery of evidence that life may exist elsewhere in the universe raises that most profound of all human questions: why does life exist at all?
Is it simply that if enough cosmic elements slop together for enough eons, eventually a molecule will form somewhere, or many somewheres, that can replicate itself over and over until it evolves into a creature that can scratch its head? Or did an all-powerful God set in motion an unfathomable process in order to give warmth and meaning to a universe that would otherwise be cold and meaningless?
May I suggest a third alternative—by far the most probable in my view (and that of most scientists), and capable of putting the recent claim for Martian life in proper perspective. If this third viewpoint were better understood and accepted, then the putative Martian fossils would enjoy far more than fifteen minutes of false and ephemeral glory, but would foster instead a sustained search for
an answer to the truly vital question that Martian life at bacterial grade should inspire.