The following is a slightly abridged "Why Care" (Chapter 4) of E. O. Wilson's The Creation. It presents a biologist view of why humanity should care about the current present-day crisis of nature. Other views have been presented earlier and will be presented later. K.N.
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Consider,
then, the following truth, which because of its importance deserves to be
called the First Principle of Human Ecology: Homo sapiens is a species confined
to an extremely small niche. True, our minds soar out to the edge of the
universe. And contract inward to subatomic particles, the two extremes
encompassing thirty powers of ten in space. In this respect our intellects are
godlike. But let’s face it, our bodies stay trapped inside a proportionately
microscopic bubble of physical constraints. We have learned how to occupy some
of Earth’s most hostile environments—but only when enclosed within airtight
containers whose environment is precisely controlled. Polar ice caps, the deep
sea, and the moon are ours to visit, but even slight malfunctions of the
life-support capsule in which we travel can be terminal to frail little Homo
sapiens. Prolonged residence there, even when physically possible, is
psychologically unbearable.
Here
is my point: Earth provides a self-regulating bubble that sustains us indefinitely
without any thought or contrivance on our own. This protective shield is the biosphere, the totality of
life, creator of all air, cleanser of all water, manager of all soil, but
itself a fragile membrane that barely clings to the surface of the plant. Humanity, as Darwin observed at the
close of The Ascent of Man, bears the indelible stamp of our lowly origin from
preexisting life forms…
The
First Principle of Human Ecology can be put another way: Alien planets are not
inn out genes. If organisms exist on Mars, Europa, or Titanis, then these
planets are in their genes, and those will surely differ radically from ours.
It
follows that human self-interest is best served by not overly harming the other
life forms on earth that still survive. Environmental damage can be defined
contrary to humanity’s inborn physical and emotional needs. We are not evolving
autonomously into something new.
Nor are we likely in the foreseeable future to change our basic nature
by genetic engineering, as some giddily futuristic writers have envisioned.
Scientific knowledge may continue to grow without limit, or it may not. But either way, human biology and
emotions will stay the same far into the future, because our immensely
complicated cerebral cortex can tolerate little tinkering, because human beings
cannot mutate like bacteria to fit every environment we spoil, and because,
ultimately, finally and quite simply, we may choose to remain true to human
nature, the heritage bequeathed us by millions of years of residence in the
biosphere.
Here,
then, is another argument for existential conservatism. Beyond the curing of obvious hereditary
diseases such as multiple sclerosis and sickle-cell anemia, by gene
substitution, the human genome will be modified only at risk. It is far better to work with human
nature as it is, by changing our social institutions and moral precepts to get
a more nearly optimal fit to our genes, than it would be to tinker with
something that took eons of trail and error to create.
The
problem of modern civilization rises from the disjunction between our ancient
and glacially slow-evolving genetic heritage at one level of evolution and our
ultra-fast cultural evolution at the other level. There are still thinkers around the world, some in commanding
political and religious positions, who wish to base moral law on the sacred
scripture of Iran Age desert kingdoms while using high technology to conduct
tribal wars—of course with the presumed blessing of their respective tribal
gods. The increasing contrast of such retrograde thinking should make us more
circumspect than ever, and not just about starting wars. It should also make us more careful
with the environment, upon which our lives ultimately depend. It will be prudent to curtail the final
and permanent obliteration of Nature until we understand more precisely what we
are and what we are doing.
The
destructive power of Homo sapiens has no limit, even though our biomass is
almost invisibly small. It is mathematically possible to log-stack all the
people on Earth into a single block of one cubic mile and lower them out of
sight in a remote part of the Grand Canyon. Yet humanity is already the first species in the history of
life to become a geophysical force.
We have, all by our bipedal, wobbly-headed selves, altered Earth’s
atmosphere and climate away from the norm. We have spread thousands of toxic
chemicals worldwide, appropriated 40 percent of the solar energy available for
photosynthesis, converted almost all of the easily arable land, dammed most of
the rivers, raised the planet sea level, and now, in a manner likely to get
everyone’s attention like nothing else before, we are close to running out of
fresh water. A collateral effect
of all this frantic activity is the continuing extinction of world ecosystems,
along with the species that compose them. This also happens to be the only
human impact that is irreversible.
With
all the troubles that humanity faces, why should we care about the condition of
living Nature? What difference will it make if a few or even half of all the
species on earth are exterminated? Many reasons exist fundamental to human
weal. Unimaginably vast sources of scientific information and biological wealth
will be destroyed. Opportunity costs, which will be better understood by our
descendants than by ourselves, will be staggering. Gone forever will be
undisclosed medicines, crops, timbers, fibers, soil-restoring vegetation,
petroleum substitutes, and other products and amenities.
Critics
of environmentalism (whatever that overused term means—aren’t we all
environmentalists?) usually wave aside the small and unfamiliar, which they
tend to classify into two categories, bugs and weeds. It is easy for them to
overlook the fact that these creatures make up most of the organisms and
species on Earth. They forget, if they ever knew, how the voracious
caterpillars of an obscure moth from the American tropics saved Australia’s
pastureland from the outgrowth of cactus; how Madagascar “weed,” the rosy
periwinkle, provided the alkaloids that cure most cases of Hodgkin’s disease
and acute childhood leukemia; how another substance from an obscure Norwegian
fungus made possible the organ transplant industry; how a chemical from the
saliva of leeches yielded a solvent that prevent blood clots during and after
surgery; and so on through the pharmacopoeia that has stretched from the herbal
medicines pf Stone Age shamans to the magic-bullet cures of present-day
biomedical science.
Because
wild natural ecosystems are in plain sight, it is also easy to take for granted
the environmental services they provide humanity. Wild species enrich the soil,
cleanse the water, and pollinate most the flowering plants. They create the very air we breathe.
Without these amenities, the reminder of human history would be nasty and
brief. The sustaining matrix of
our existence is the green plants, along with legions of microorganisms and
tiny invertebrates. These
organisms support the world because they are so genetically diverse, allowing
them to divide roles in the ecosystem in a fine degree of resolution, and so
abundant that at least a few occupy virtually every square meter of Earth’s
surface. Their functions in the
ecosystem are redundant; if one species is eliminated, there is often another
able to expand and at least partially take its place. All together the other species, mostly bugs and weeds, run
the world exactly as we should want it run, because during prehistory humanity
evolved to depend upon their combined actions and the insurance that
biodiversity provides world stability.
Living
nature is nothing more than the commonality of organisms in the wild state and
the physical and chemical equilibrium their species generate through
interaction with one another. But
it is also nothing less than that commonality and equilibrium. The power of
living Nature lies in sustainability through complexity. Destabilize it by
degrading it to a simpler state, as we seem bent on doing, and the result could
be catastrophic. The organisms most affected are likely to be the largest and
most complex, including human beings.
More
respect is due the little things that run the world. Being and entomologist, I
will now use insects to plead the class-action case on behalf of the Earth’s
entire afflicted fauna and flora.
The diversity of insects is the greatest documented among all organisms:
the total number of species classified in 2006 is about 900,000. The true number, combining those both
known and remaining to be discovered, may exceed 10 million. The biomass of
insects is immense: about a million trillion are alive at any moment. Ants alone, of which there may be 10
thousand trillion, weigh roughly as much as all 6.5 billion human beings. While these estimates are still shaky
(to put the matter generously), there is no doubt that insects rank near the
top among animals in physical bulk.
They are rivaled there in biomass by copepods (minute sea crustaceans),
mites (tiny spider like arthropods), and, at the very apex, the amazing
nematode worms, whose vast population swarms, probably representing millions of
species, make up four-fifth of all animals on Earth. Can anyone believe that
these little creatures are just there to fill space?
People
need insects to survive, but insects do not need us. If all humankind were to
disappear tomorrow, it is unlikely that a single insect species would go
extinct, except three forms of human body and head lice. Even then there would remain
gorilla lice, closely related to the human parasites and available to carry on
at least something close to the ancient line. In two or three centuries, with
humans gone, the ecosystems of the world regenerate back to the rich state of
near equilibrium that existed ten thousand years ago or so, minus of course the
many species that we have pushed into extinction.
But
if insects were to vanish, the terrestrial environment would soon collapse into
chaos. Picture the steps of the
cataclysm, as it would likely unfold across the first several decades:
·
A majority of the
flowering plants, upon being deprived of their pollinators, cease to reproduce.
·
Most herbaceous plant
species among them spiral down to extinction. Insect-pollinated shrubs and
trees hang on for a few more years, in rare cases up to centuries.
·
The great majority of
birds and other land vertebrates, now denied the specialized foliage, fruits,
and insects prey on which they feed, follow the plants into oblivion.
·
The soil remains
largely unturned, accelerating plant decline, because insects, not earthworms
as generally supposed, are the principal turner and renewer of the soil.
·
Populations of fungi
and bacteria explode and remain at a peak over a few years while metabolizing
the dead plant and animal material that pile up.
·
Wind-pollinated
grasses and a handful of fern and conifer species spread over much of the
deforested terrain, then decline to some extent as the soil deteriorates.
·
The human species
survives, able to fall back on wind-pollinated grains and marine fishing. But
amid widespread starvation during the first several decades, human population
plunges to a small fraction of their former level. The wars for control of the
dwindling resources, the suffering, and the tumultuous decline to dark-age
barbarism would be unprecedented in human history.
·
Clinging to survival
in a devastated world, and trapped in an ecological dark age, the survivors
would offer prayers for the return of weeds and bugs.
The bottom line of my scenario is this:
be careful with pesticides. Do not give thought to diminishing the insect
world. It would be a serious mistake to let even one species out of the
millions on Earth go extinct. That is, let me add quickly, with an extremely
few exceptions. I’d vote for the
eradication of the aforementioned lice (the gravamen against them: limited to
humans, serious skin pests, threats to quality of life, carriers of
disease). Also, I’d not mourn the
passing of mosquitoes of the Anopheles gambiae complex of Africa, species that
are specialized to feed on human blood, during which they transmit malignant malaria. Keep their DNA for future research and
let them go. Let us not be
conservation absolutists when it comes to creatures specialized to feed on
human beings.
In
the real world there is a need to control only the tiny fraction of inset
species, perhaps as few as one out of ten thousand, that are consistently
harmful to humans. In most cases
control means to reduce and if possible to eradicate populations of such
species in countries where they are aliens, usually having been transported
there by humans as unintended hitchhikers. Take, for example, the red imported fire ant that has vexed
the southern United States since the 1940s and has recently spread from there
to California, the Caribbean islands, Australia, New Zealand, and China. It
inflicts hundreds of millions of dollars in agricultural losses each year. Its
stings are painful and occasionally fatal, usually as a result of anaphylactic
shock triggered by the venom. It
has displaced some native insects and reduced wildlife populations. Obviously
it would be wise to erase invading populations of the red fire ant—if only
entomologists could find a way.
But the same is not true for southern Brazil and northern Argentina,
where the ant is not imported but a native species, ecologically adjusted by
millions of years of co-evolution with other native species. In their South American home they are
in balance with predators, and competitors. Otherwise they would have become extinct ages ago. In the United States their enemies are
fewer in number and weaker.
Removal of the alien fire ant populations would be healthy for both
people and the environment of the countries they have colonized. Removal from South America, in
contrast, might cause damage to the ecosystems in which they are co-adapted
with other species and live harmoniously.
One
of the daunting challenges of the modern discipline of ecology is to sort out
such pluses and minuses of living Nature in order better to define the inner
structure of the biosphere. There is hope that in time researchers will learn
how ecosystems are assembled, how they are sustained, and more precisely how
they come to be destabilized. Earth is a laboratory wherein Nature…has laid
before us the results of countless experiments. She speaks to us; now let us
listen.
The
increased disillusionment was even more pronounced when respondents were asked
their impressions of how the war was going. The poll found that 68 percent
thought the fighting was going “somewhat badly” or “very badly,” compared with
42 percent who had those impressions in November.
