400-600 words reflection on two Gould essays
Gould, Stephen Jay, Natural History, 00280712, Sep90, Vol. 99, Issue 9
The Golden Rule – A Proper Scale for Our Environmental Crisis
One among millions of species, we have a parochial, but legitimate, interest in our own
survival. It takes a particular kind of genius or deep understanding to transcend this most
pervasive of all conceptual biases and to capture a phenomenon by grasping a proper
scale beyond the measuring rods of our own world. Phenomena unfold on their own
appropriate scales of space and time and may be invisible in our myopic world of
dimensions assessed by comparison with human height and times metered by human life
spans. So much of accumulating importance at earthly scales—the results of geological
erosion, evolutionary changes in lineages—is invisible by the measuring rod of a human
life. So much that matters to particles in the microscopic world of molecules—like the
history of a dust grain subject to Brownian motion—either averages out to stability at our
scale or simply stands below our limits of perception.
The case at hand is a classic representative of a genre (environmentalists versus
developers) made familiar in recent struggles to save endangered populations—the snail
darter of a few years back, or the northern spotted owl versus timber interests (decided,
properly in my view, for the birds).
The University of Arizona, with the backing of an international consortium of
astronomers, wishes to build a complex of telescopes atop Mount Graham in southeastern
Arizona. But the old-growth spruce-fir habitat on the mountaintop forms the heart of the
range for Tamiasciurus hudsonicus grahamensis, the Mount Graham red squirrel—a
distinct subspecies that lives nowhere else and that forms the southernmost population of
the entire species. The population has already been reduced to some 100 survivors, and
destruction of several acres of spruce-fir growth (to build the telescopes) within the 700
or so remaining acres of best habitat might well administer a coup de grace to this fragile
population.
I cannot state an expert opinion on details of this controversy. Many questions
need to be answered. Is the squirrel population already too small to survive in any case?
If not, could the population, with proper management, coexist with the telescopes in the
remaining habitat? (Environmentalists fear change of microclimate as much or more than
loss of acreage. Reduction of forest canopy will increase wind and sun, producing a drop
in humidity. The squirrels survive winter by storing unopened cones in food caches
beside trees. If humidity falls, cones may dry out and open, causing loss of seeds and
destruction of food.)
I do not think that, practically or morally, we can defend a policy of saving every
distinct local population of organisms. I can cite a good rationale for the preservation of
species—for each species is a unique and separate natural object that, once lost, can never
be reconstituted. But subspecies are distinct local populations of species with broader
geographical ranges. Subspecies are dynamic, interbreedable, and constantly changing;
what then are we saving by declaring them all inviolate? Thus, I confess that I do not
agree with all arguments advanced by defenders of the Mount Graham red squirrel. One
leaflet, for example, argues: "The population has been recently shown to have a fixed,
homozygous allele which is unique in Western North America." Sorry folks. I will stoutly
defend species, but we cannot ask for the preservation of every distinctive gene, unless
we find a way to abolish death itself (for many organisms carry unique mutations).
No, I think that for local populations of species with broader ranges, the brief for
preservation must be made on a case-by-case basis, not a general principle of
preservation (lest the environmental movement ultimately lose popular support for trying
to freeze a dynamic evolutionary world in status quo). On this proper basis of individual
merit, I am entirely persuaded that the Mount Graham red squirrel should be protected
and the astronomical observatory built elsewhere—and for two reasons. First, the squirrel
itself: the Mount Graham red is an unusually interesting local population within an
important species. It is isolated from all other populations and forms the southernmost
extreme of the species' range. Such peripheral populations, living in marginal habitats,
are of special interest to students of evolution.
Second, the habitat: environmentalists continually face the political reality that
support and funding can be won for soft, cuddly, and "attractive" animals, but not for
slimy, grubby, and ugly creatures (of potentially greater evolutionary interest and
practical significance) or for habitats. This situation has led to the practical concept of
"umbrella" or "indicator" species—surrogates for a larger ecological entity worthy of
preservation. Thus, the giant panda (really quite a boring and ornery creature despite its
good looks) raises money to save the remaining bamboo forests of China (and a plethora
of other endangered creatures with no political clout); the northern spotted owl has just
rescued some magnificent stands of old-growth giant cedars, Douglas fir, and redwoods;
and the Mount Graham red squirrel may save a rare and precious habitat of extraordinary
evolutionary interest.
The Pinaleno Mountains, reaching 10,720 feet at Mount Graham, are an isolated
fault-block range separated from others by alluvial and desert valleys that dip to less than
3,000 feet in elevation. The high peaks of the Pinalenos contain an important and unusual
fauna for two reasons. First, they harbor a junction of two biogeographic provinces: the
Nearctic, or northern, by way of the Colorado Plateau, and the Neotropical, or southern,
via the Mexican Plateau. The Mount Graham red squirrel (a northern species) can live
this far south because high elevations reproduce the climate and habitat found near sea
level in the more congenial north. Second, and more important to evolutionists, the old-
growth spruce-fir habitats on the high peaks of the Pinalenos are isolated "sky islands"—
10,000-year-old remnants of a habitat more widely spread over the region during the
height of the last Ice Age. In evolutionary terms, these isolated pieces of habitat are true
islands—patches of more northern microclimate surrounded by southern desert. They are
functionally equivalent to bits of land in the ocean. Consider the role that islands (like the
Galapagos) have played both in developing the concepts of evolutionary theory and in
acting as cradles of origin (through isolation) or vestiges of preservation for biological
novelties.
Thus, whether or not the telescopes will drive the Mount Graham red squirrel to
extinction (an unsettled question well outside my area of expertise), the sky islands of the
Pinalenos are precious habitats that should not be compromised. Let the Mount Graham
red squirrel, so worthy of preservation in its own right, also serve as an indicator species
for the unique and fragile habitat that it occupies.
But why should I, a confirmed eastern urbanite, choose to involve myself in the
case of the Mount Graham red squirrel? The answer, unsurprisingly, is that I have been
enlisted—involuntarily, unawares, and on the wrong side to boot. I am simply fighting
mad, and fighting back.
The June 7, 1990, Wall Street Journal ran a pro-development, anti-squirrel
opinion piece by Michael D. Copeland (identified as "executive director of the Political
Economy Research Center in Bozeman, Montana") under the patently absurd title: "No
Red Squirrels? Mother Nature May Be Better Off." (I can at least grasp, while still
rejecting, the claim that nature would be no worse off if the squirrels died, but I am
utterly befuddled at how anyone could argue that the squirrels inflict a positive harm
upon the mother of us all!) In any case, Copeland misunderstood my writings in
formulating a supposedly scientific argument for his position.
Now, scarcely a day goes by when I do not read a misrepresentation of my views
(usually by creationists, racists, or football fans, in order of frequency). My response to
nearly all misquotation is the effective retort of preference: utter silence. (Honorable
intellectual disagreement should always be addressed; misquotation should be ignored,
when possible and politically practical.) I make an exception in this case because
Copeland cited me in the service of a classic false argument—indeed, the standard,
almost canonical misuse of my profession of paleontology in debates about extinction.
Paleontologists have been enlisted again and again, in opposition to our actual opinions
and in support of attitudes that most of us regard as anathema, to uphold arguments by
developers about the irrelevance (or even, in this case, the benevolence) of modern
anthropogenic extinction. This standard error is a classic example of failure to understand
the importance of scale—thus I return to the premise and structure of my introductory
paragraphs.
Paleontologists do discuss the inevitability of extinction for all species—in the
long run and on the broad scale of geological time. We are fond of saying that 99 percent
or more of all species that ever lived are now extinct. (My colleague Dave Raup often
opens talks on extinction with a zinging one-liner: "To a first approximation, all species
are extinct.") We do therefore identify extinction as the normal fate of species. We also
talk a lot—more of late since new data have made the field so exciting—about the mass
extinctions that punctuate the history of life from time to time. We do discuss the issue of
eventual "recovery" from these extinctions, in the sense that life does rebuild or surpass
its former diversity after several million years. Finally, we do allow that mass extinctions
break up stable faunas and, in this sense, permit or even foster evolutionary innovations
well down the road (including the dominance of mammals and the eventual origin of
humans, following the death of dinosaurs).
From this set of statements about extinction in the fullness of geological time (on
scales of millions of years), some apologists for development have argued that extinction
at any scale (even of local populations within years or decades) poses no biological worry
but, on the contrary, must be viewed as a comfortable part of an inevitable natural order.
Or so Copeland states:
Suppose we lost a species. How devastating would that be? "Mass extinctions
have been recorded since the dawn of paleontology," writes Harvard paleontologist
Stephen Gould ... the most severe of these occurred approximately 250 million years ago
... with an estimated 96 percent extinction of species, says Mr. Gould. ... There is general
agreement among scientists that today's species represent a small proportion of all those
that have ever existed—probably less than 1 percent. This means that more than 99
percent of all species ever living have become extinct.
From these facts, largely irrelevant to red squirrels on Mount Graham, Copeland
makes inferences about the benevolence of extinction in general (although the argument
applies only to geological scales):
Yet, in spite of these extinctions, both Mr. Gould and University of Chicago
paleontologist Jack Sepkoski say that the actual number of living species has probably
increased over time. [True, but not as a result of mass extinctions, despite Copeland's
next sentence.] The "niches" created by extinctions provide an opportunity for a vigorous
development of new species.... Thus, evolutionary history appears to have been
characterized by millions of species extinctions and subsequent increases in species
numbers. Indeed, by attempting to preserve species living on the brink of extinction, we
may be wasting time, effort and money on animals that will disappear over time,
regardless of our efforts.
But all will "disappear over time, regardless of our efforts"—millions of years
from now for most species if we don't interfere. The mean life span of marine
invertebrate species lies between 5 and 10 million years; terrestrial vertebrate species turn
over more rapidly, but still average in the millions. By contrast, Homo sapiens may be
only 250,000 years old or so and may enjoy a considerable future if we don't self-
destruct. Similarly, recovery from mass extinction takes its natural measure in millions of
years—as much as 10 million or more for fully rekindled diversity after major
catastrophic events.
These are the natural time scales of evolution and geology on our planet. But what
can such vastness possibly mean for our legitimately parochial interest in ourselves, our
ethnic groups, our nations, our cultural traditions, our bloodlines? Of what conceivable
significance to us is the prospect of recovery from mass extinction 10 million years down
the road if our entire species, not to mention our personal family lineage, has so little
prospect of surviving that long?
Capacity for recovery at geological scales has no bearing whatever upon the
meaning of extinction today. We are not protecting Mount Graham red squirrels because
we fear for global stability in a distant future not likely to include us. We are trying to
preserve populations and environments because the comfort and decency of our present
lives, and those of fellow species that share our planet, depend upon such stability. Mass
extinctions may not threaten distant futures, but they are decidedly unpleasant for species
in the throes of their power (particularly if triggered by such truly catastrophic events as
extraterrestrial impact). At the appropriate scale of our lives, we are just a species in the
midst of such a moment. And to say that we should let the squirrels go (at our immediate
scale) because all species eventually die (at geological scales) makes about as much sense
as arguing that we shouldn't treat an easily curable childhood infection because all
humans are ultimately and inevitably mortal. I love geological time—a wondrous and
expansive notion that sets the foundation of my chosen profession, but such immensity is
not the proper scale of my personal life.
The same issue of scale underlies the main contributions that my profession of
paleontology might make to our larger search for an environmental ethic. This decade, a
prelude to the millennium, is widely and correctly viewed as a turning point that will lead
either to environmental perdition or stabilization. We have fouled local nests before and
driven regional faunas to extinction, but we have never been able to unleash planetary
effects before our current concern with ozone holes and putative global warming. In this
context, we are searching for proper themes and language to express our environmental
worries.
I don't know that paleontology has a great deal to offer, but I would advance one
geological insight to combat a well-meaning, but seriously flawed (and all too common),
position and to focus attention on the right issue at the proper scale. Two linked
arguments are often promoted as a basis for an environmental ethic:
1. That we live on a fragile planet now subject to permanent derailment and disruption by human intervention;
2. That humans must learn to act as stewards for this threatened world.
Such views, however well intentioned, are rooted in the old sin of pride and
exaggerated self-importance. We are one among millions of species, stewards of nothing.
By what argument could we, arising just a geological microsecond ago, become
responsible for the affairs of a world 4.5 billion years old, teeming with life that has been
evolving and diversifying for at least three-quarters of that immense span? Nature does
not exist for us, had no idea we were coming, and doesn't give a damn about us.
This assertion of ultimate impotence could be countered if we, despite our late
arrival, now held power over the planet's future (argument number one above). But we
don't, despite popular misperception of our might. We are virtually powerless over the
earth at our planet's own geological time scale. All the megatonnage in our nuclear
arsenals yield but one ten-thousandth the power of the asteroid that might have triggered
the Cretaceous mass extinction. Yet the earth survived that larger shock and, in wiping
out dinosaurs, paved the road for the evolution of large mammals, including humans. We
fear global warming, yet even the most radical model yields an earth far cooler than many
happy and prosperous times of a prehuman past. We can surely destroy ourselves, and
take many other species with us, but we can barely dent bacterial diversity and will surely
not remove many million species of insects and mites. On geological scales, our planet
will take good care of itself and let time clear the impact of any human malfeasance.
People who do not appreciate the fundamental principle of appropriate scales
often misread such an argument as a claim that we may therefore cease to worry about
environmental deterioration—just as Copeland argued falsely that we need not fret about
extinction. But I raise the same counterargument. We cannot threaten at geological
scales, but such vastness is entirely inappropriate. We have a legitimately parochial
interest in our own lives, the happiness and prosperity of our children, the suffering of
our fellows. The planet will recover from nuclear holocaust, but we will be killed and
maimed by the billions, and our cultures will perish. The earth will prosper if polar
icecaps melt under a global greenhouse, but most of our major cities, built at sea level as
ports and harbors, will founder, and changing agricultural patterns will uproot our
populations.
We must squarely face an unpleasant historical fact. The conservation movement
was born, in large part, as an elitist attempt by wealthy social leaders to preserve
wilderness as a domain for patrician leisure and contemplation (against the image, so to
speak, of poor immigrants traipsing in hordes through the woods with their Sunday picnic
baskets). We have never entirely shaken this legacy of environmentalism as something
opposed to immediate human needs, particularly of the impoverished and unfortunate.
But the Third World expands and contains most of the pristine habitat that we yearn to
preserve. Environmental movements cannot prevail until they convince people that clean
air and water, solar power, recycling, and reforestation are best solutions (as they are) for
human needs at human scales—and not for impossibly distant planetary futures.
I have a decidedly unradical suggestion to make about an appropriate
environmental ethic—one rooted, with this entire essay, in the issue of appropriate human
scale versus the majesty, but irrelevance, of geological time. I have never been much
attracted to the Kantian categorical imperative in searching for an ethic—to moral laws
that are absolute and unconditional and do not involve any ulterior motive or end. The
world is too complex and sloppy for such uncompromising attitudes (and God help us if
we embrace the wrong principle, and then fight wars, kill, and maim in our absolute
certainty). I prefer the messier "hypothetical imperatives" that invoke desire, negotiation,
and reciprocity. Of these "lesser," but altogether wiser and deeper, principles, one has
stood out for its independent derivation, with different words but to the same effect, in
culture after culture. I imagine that our various societies grope toward this principle
because structural stability, and basic decency necessary for any tolerable life, demand
such a maxim. Christians call this principle the "golden rule"; Plato, Hillel, and
Confucius knew the same maxim by other names. I cannot think of a better principle
based on enlightened self-interest. If we all treated others as we wish to be treated
ourselves, then decency and stability would have to prevail.
I suggest that we execute such a pact with our planet. She holds all the cards and
has immense power over us—so such a compact, which we desperately need but she does
not at her own time scale, would be a blessing for us, and an indulgence for her. We had
better sign the papers while she is still willing to make a deal. If we treat her nicely, she
will keep us going for a while. If we scratch her, she will bleed, kick us out, bandage up,
and go about her business at her planetary scale. Poor Richard told us that "necessity
never made a good bargain," but the earth is kinder than human agents in the "art of the
deal." She will uphold her end; we must now go and do likewise.