[Vision2020] By the End of the Century Half of All Species Will Be Extinct.

[Ted Moffett]

http://news.independent.co.uk/environment/article2494659.ece
 Animal Extinction - the greatest threat to mankind
 By the end of the century half of all species will be extinct. Does that
matter?
By Julia Whitty Published: 30 April 2007

In the final stages of dehydration the body shrinks, robbing youth from the
young as the skin puckers, eyes recede into orbits, and the tongue swells
and cracks. Brain cells shrivel and muscles seize. The kidneys shut down.
Blood volume drops, triggering hypovolemic shock, with its attendant
respiratory and cardiac failures. These combined assaults disrupt the
chemical and electrical pathways of the body until all systems cascade
toward death.

Such is also the path of a dying species. Beyond a critical point, the
collective body of a unique kind of mammal or bird or amphibian or tree
cannot be salvaged, no matter the first aid rendered. Too few individuals
spread too far apart, or too genetically weakened, are susceptible to even
small natural disasters: a passing thunderstorm; an unexpected freeze;
drought. At fewer than 50 members, populations experience increasingly
random fluctuations until a kind of fatal arrhythmia takes hold. Eventually,
an entire genetic legacy, born in the beginnings of life on earth, is
removed from the future.

Scientists recognise that species continually disappear at a background
extinction rate estimated at about one species per million per year, with
new species replacing the lost in a sustainable fashion. Occasional mass
extinctions convulse this orderly norm, followed by excruciatingly slow
recoveries as new species emerge from the remaining gene-pool, until the
world is once again repopulated by a different catalogue of flora and fauna.

>From what we understand so far, five great extinction events have reshaped
earth in cataclysmic ways in the past 439 million years, each one wiping out
between 50 and 95 per cent of the life of the day, including the dominant
life forms; the most recent event killing off the non-avian dinosaurs.
Speciations followed, but an analysis published in Nature showed that it
takes 10 million years before biological diversity even begins to approach
what existed before a die-off.

Today we're living through the sixth great extinction, sometimes known as
the Holocene extinction event. We carried its seeds with us 50,000 years ago
as we migrated beyond Africa with Stone Age blades, darts, and harpoons,
entering pristine Ice Age ecosystems and changing them forever by wiping out
at least some of the unique megafauna of the times, including, perhaps, the
sabre-toothed cats and woolly mammoths. When the ice retreated, we
terminated the long and biologically rich epoch sometimes called the Edenic
period with assaults from our newest weapons: hoes, scythes, cattle, goats,
and pigs.

But, as harmful as our forebears may have been, nothing compares to what's
under way today. Throughout the 20th century the causes of extinction -
habitat degradation, overexploitation, agricultural monocultures,
human-borne invasive species, human-induced climate-change - increased
exponentially, until now in the 21st century the rate is nothing short of
explosive. The World Conservation Union's Red List - a database measuring
the global status of Earth's 1.5 million scientifically named species -
tells a haunting tale of unchecked, unaddressed, and accelerating biocide.

When we hear of extinction, most of us think of the plight of the rhino,
tiger, panda or blue whale. But these sad sagas are only small pieces of the
extinction puzzle. The overall numbers are terrifying. Of the 40,168 species
that the 10,000 scientists in the World Conservation Union have assessed,
one in four mammals, one in eight birds, one in three amphibians, one in
three conifers and other gymnosperms are at risk of extinction. The peril
faced by other classes of organisms is less thoroughly analysed, but fully
40 per cent of the examined species of planet earth are in danger, including
perhaps 51 per cent of reptiles, 52 per cent of insects, and 73 per cent of
flowering plants.

By the most conservative measure - based on the last century's recorded
extinctions - the current rate of extinction is 100 times the background
rate. But the eminent Harvard biologist Edward O Wilson, and other
scientists, estimate that the true rate is more like 1,000 to 10,000 times
the background rate. The actual annual sum is only an educated guess,
because no scientist believes that the tally of life ends at the 1.5 million
species already discovered; estimates range as high as 100 million species
on earth, with 10 million as the median guess. Bracketed between best- and
worst-case scenarios, then, somewhere between 2.7 and 270 species are erased
from existence every day. Including today.

We now understand that the majority of life on Earth has never been - and
will never be - known to us. In a staggering forecast, Wilson predicts that
our present course will lead to the extinction of half of all plant and
animal species by 2100.

You probably had no idea. Few do. A poll by the American Museum of Natural
History finds that seven in 10 biologists believe that mass extinction poses
a colossal threat to human existence, a more serious environmental problem
than even its contributor, global warming; and that the dangers of mass
extinction are woefully underestimated by almost everyone outside science.
In the 200 years since French naturalist Georges Cuvier first floated the
concept of extinction, after examining fossil bones and concluding "the
existence of a world previous to ours, destroyed by some sort of
catastrophe", we have only slowly recognised and attempted to correct our
own catastrophic behaviour.

Some nations move more slowly than others. In 1992, an international summit
produced a treaty called the Convention on Biological Diversity that was
subsequently ratified by 190 nations - all except the unlikely coalition of
the United States, Iraq, the Vatican, Somalia, Andorra and Brunei. The
European Union later called on the world to arrest the decline of species
and ecosystems by 2010. Last year, worried biodiversity experts called for
the establishment of a scientific body akin to the Intergovernmental Panel
on Climate Change to provide a united voice on the extinction crisis and
urge governments to action.

Yet, despite these efforts, the Red List, updated every two years, continues
to show metastatic growth. There are a few heartening examples of so-called
Lazarus species lost and then found: the wollemi pine and the mahogany
glider in Australia, the Jerdon's courser in India, the takahe in New
Zealand, and, maybe, the ivory-billed woodpecker in the United States. But
for virtually all others, the Red List is a dry country with little hope of
rain, as species ratchet down the listings from secure to vulnerable, to
endangered, to critically endangered, to extinct.

All these disappearing species are part of a fragile membrane of organisms
wrapped around the Earth so thinly, writes Wilson, that it "cannot be seen
edgewise from a space shuttle, yet so internally complex that most species
composing it remain undiscovered". We owe everything to this membrane of
life. Literally everything. The air we breathe. The food we eat. The
materials of our homes, clothes, books, computers, medicines. Goods and
services that we can't even imagine we'll someday need will come from
species we have yet to identify. The proverbial cure for cancer. The genetic
fountain of youth. Immortality. Mortality. The living membrane we so
recklessly destroy is existence itself.

Biodiversity is defined as the sum of an area's genes (the building blocks
of inheritance), species (organisms that can interbreed), and ecosystems
(amalgamations of species in their geological and chemical landscapes). The
richer an area's biodiversity, the tougher its immune system, since
biodiversity includes not only the number of species but also the number of
individuals within that species, and all the inherent genetic variations -
life's only army against the diseases of oblivion.

Yet it's a mistake to think that critical genetic pools exist only in the
gaudy show of the coral reefs, or the cacophony of the rainforest. Although
a hallmark of the desert is the sparseness of its garden, the orderly
progression of plants and the understated camouflage of its animals, this is
only an illusion. Turn the desert inside out and upside down and you'll
discover its true nature. Escaping drought and heat, life goes underground
in a tangled overexuberance of roots and burrows reminiscent of a rainforest
canopy, competing for moisture, not light. Animal trails criss-cross this
subterranean realm in private burrows engineered, inhabited, stolen, shared
and fought over by ants, beetles, wasps, cicadas, tarantulas, spiders,
lizards, snakes, mice, squirrels, rats, foxes, tortoises, badgers and
coyotes.

To survive the heat and drought, desert life pioneers ingenious solutions.
Coyotes dig and maintain wells in arroyos, probing deep for water.
White-winged doves use their bodies as canteens, drinking enough when the
opportunity arises to increase their bodyweight by more than 15 per cent.
Black-tailed jack rabbits tolerate internal temperatures of 111F. Western
box turtles store water in their oversized bladders and urinate on
themselves to stay cool. Mesquite grows taproots more than 160ft deep in
search of moisture.

These life-forms and their life strategies compose what we might think of as
the "body" of the desert, with some species the lungs and others the liver,
the blood, the skin. The trend in scientific investigation in recent decades
has been toward understanding the interconnectedness of the bodily
components, i.e. the effect one species has on the others. The loss of even
one species irrevocably changes the desert (or the tundra, rainforest,
prairie, coastal estuary, coral reef, and so on) as we know it, just as the
loss of each human being changes his or her family forever.

Nowhere is this better proven than in a 12-year study conducted in the
Chihuahuan desert by James H Brown and Edward Heske of the University of New
Mexico. When a kangaroo-rat guild composed of three closely related species
was removed, shrublands quickly converted to grasslands, which supported
fewer annual plants, which in turn supported fewer birds. Even humble
players mediate stability. So when you and I hear of this year's extinction
of the Yangtze river dolphin, and think, "how sad", we're not calculating
the deepest cost: that extinctions lead to co-extinctions because most
living things on Earth support a few symbionts, while keystone species
influence and support myriad plants and animals. Army ants, for example, are
known to support 100 known species, from beetles to birds. A European study
finds steep declines in honeybee diversity in the past 25 years but also
significant attendant declines in plants that depend on bees for pollination
- a job estimated to be worth £50bn worldwide. Meanwhile, beekeepers in 24
American states report that perhaps 70 per cent of their colonies have
recently died off, threatening £7bn in US agriculture. And bees are only a
small part of the pollinator crisis.

One of the most alarming developments is the rapid decline not just of
species but of higher taxa, such as the class Amphibia, the
300-million-year-old group of frogs, salamanders, newts and toads hardy
enough to have preceded and then outlived most dinosaurs. Biologists first
noticed die-offs two decades ago, and, since then, have watched as seemingly
robust amphibian species vanished in as little as six months. The causes
cover the spectrum of human environmental assaults, including rising
ultraviolet radiation from a thinning ozone layer, increases in pollutants
and pesticides, habitat loss from agriculture and urbanisation, invasions of
exotic species, the wildlife trade, light pollution, and fungal diseases.
Sometimes stressors merge to form an unwholesome synergy; an African frog
brought to the West in the 1950s for use in human pregnancy tests likely
introduced a fungus deadly to native frogs. Meanwhile, a recent analysis in
Nature estimated that, in the past 20 years, at least 70 species of South
American frogs had gone extinct as a result of climate change.

In a 2004 analysis published in Science, Lian Pin Koh and his colleagues
predict that an initially modest co-extinction rate will climb alarmingly as
host extinctions rise in the near future. Graphed out, the forecast mirrors
the rising curve of an infectious disease, with the human species acting all
the parts: the pathogen, the vector, the Typhoid Mary who refuses
culpability, and, ultimately, one of up to 100 million victims.

"Rewilding" is bigger, broader, and bolder than humans have thought before.
Many conservation biologists believe it's our best hope for arresting the
sixth great extinction. Wilson calls it "mainstream conservation writ large
for future generations". This is because more of what we've done until now -
protecting pretty landscapes, attempts at sustainable development,
community-based conservation and ecosystem management - will not preserve
biodiversity through the critical next century. By then, half of all species
will be lost, by Wilson's calculation.

To save Earth's living membrane, we must put its shattered pieces back
together. Only "megapreserves" modelled on a deep scientific understanding
of continent-wide ecosystem needs hold that promise. "What I have been
preparing to say is this," wrote Thoreau more than 150 years ago. "In
wildness is the preservation of the world." This, science finally
understands.

The Wildlands Project, the conservation group spearheading the drive to
rewild North America - by reconnecting remaining wildernesses (parks,
refuges, national forests, and local land trust holdings) through corridors
- calls for reconnecting wild North America in four broad "megalinkages":
along the Rocky Mountain spine of the continent from Alaska to Mexico;
across the arctic/boreal from Alaska to Labrador; along the Atlantic via the
Appalachians; and along the Pacific via the Sierra Nevada into the Baja
peninsula. Within each megalinkage, core protected areas would be connected
by mosaics of public and private lands providing safe passage for wildlife
to travel freely. Broad, vegetated overpasses would link wilderness areas
split by roads. Private landowners would be enticed to either donate land or
adopt policies of good stewardship along critical pathways.

It's a radical vision, one the Wildlands Project expects will take 100 years
or more to complete, and one that has won the project a special enmity from
those who view environmentalists with suspicion. Yet the core brainchild of
the Wildlands Project - that true conservation must happen on an
ecosystem-wide scale - is now widely accepted. Many conservation
organisations are already collaborating on the project, including
international players such as Naturalia in Mexico, US national heavyweights
like Defenders of Wildlife, and regional experts from the Southern Rockies
Ecosystem Project to the Grand Canyon Wildlands Council. Kim Vacariu, the
South-west director of the US's Wildlands Project, reports that ranchers are
coming round, one town meeting at a time, and that there is interest, if not
yet support, from the insurance industry and others who "face the reality of
car-wildlife collisions daily".

At its heart, rewilding is based on living with the monster under the bed,
since the big, scary animals that frightened us in childhood, and still do,
are the fierce guardians of biodiversity. Without wolves, wolverines,
grizzlies, black bears, mountain lions and jaguars, wild populations shift
toward the herbivores, who proceed to eat plants into extinction, taking
birds, bees, reptiles, amphibians and rodents with them. A tenet of ecology
states that the world is green because carnivores eat herbivores. Yet the
big carnivores continue to die out because we fear and hunt them and because
they need more room than we preserve and connect. Male wolverines, for
instance, can possess home ranges of 600 sq m. Translated, Greater London
would have room for only one.

The first campaign out of the Wildlands Project's starting gate is the
"spine of the continent", along the mountains from Alaska to Mexico, today
fractured by roads, logging, oil and gas development, grazing, ski resorts,
motorised back-country recreation and sprawl.

The spine already contains dozens of core wildlands, including wilderness
areas, national parks, national monuments, wildlife refuges, and private
holdings. On the map, these scattered fragments look like debris falls from
meteorite strikes. Some are already partially buffered by surrounding
protected areas such as national forests. But all need interconnecting
linkages across public and private lands - farms, ranches, suburbia - to
facilitate the travels of big carnivores and the net of biodiversity that
they tow behind them.

The Wildlands Project has also identified the five most critically
endangered wildlife linkages along the spine, each associated with a
keystone species. Grizzlies already pinched at Crowsnest Pass on Highway
Three, between Alberta and British Columbia, will be entirely cut off from
the bigger gene pool to the north if a larger road is built. Greater sage
grouse, Canada lynx, black bears and jaguars face their own lethal obstacles
further south.

But by far the most endangered wildlife-linkage is the borderland between
the US and Mexico. The Sky Islands straddle this boundary, and some of North
America's most threatened wildlife - jaguars, bison, Sonoran pronghorn,
Mexican wolves - cross, or need to cross, here in the course of their life's
travels. Unfortunately for wildlife, Mexican workers cross here too. Men,
women, and children, running at night, one-gallon water jugs in hand.

The problem for wildlife is not so much the intrusions of illegal Mexican
workers but the 700-mile border fence proposed to keep them out. From an
ecological perspective, it will sever the spine at the lumbar, paralysing
the lower continent.

Here, in a nutshell, is all that's wrong with our treatment of nature. Amid
all the moral, practical, and legal issues with the border fence, the
biological catastrophe has barely been noted. It's as if extinction is not
contagious and we won't catch it.

If, as some indigenous people believe, the jaguar was sent to the world to
test the will and integrity of human beings, then surely we need to
reassess. Border fences have terrible consequences. One between India and
Pakistan forces starving bears and leopards, which can no longer traverse
their feeding territories, to attack villagers.

The truth is that wilderness is more dangerous to us caged than free - and
has far more value to us wild than consumed. Wilson suggests the time has
come to rename the "environmentalist view" the "real-world view", and to
replace the gross national product with the more comprehensive "genuine
progress indicator", which estimates the true environmental costs of
farming, fishing, grazing, mining, smelting, driving, flying, building,
paving, computing, medicating and so on. Until then, it's like keeping a
ledger recording income but not expenses. Like us, the Earth has a finite
budget.

*Reprinted with permission from Mother Jones magazine. (c) 2007, Foundation
for National Progress. The Fragile Edge: Diving and Other Adventures in the
South Pacific by Julia Whitty is published by Houghton Mifflin on 7 May*

*Disappearing World*

More than 16,000 species of the world's mammals, birds, plants and other
organisms are at present officially regarded as threatened with extinction
to one degree or another, according to the Red List.

Maintained by the Swiss-based World Conservation Union (usually known by the
initials IUCN), the Red List is one of the gloomiest books in the world, and
is set to get even gloomier.

Since 1963 it has attempted to set out the conservation status of the
planet's wildlife, in a series of categories which now range from Extinct
(naturally), through Critically Endangered, Endangered, Vulnerable and
Near-Threatened, and finishing with Least Concern. The numbers in the
"threatened" categories are steadily rising.

Taxonomists at the IUCN regularly attempt to update the list, but that is a
massive job to undertake - there are about 5,000 mammal species in the world
and about 10,000 birds, but more than 300,000 types of plant, and
undoubtedly well over a million insect species, and perhaps many more. Some
species, such as beetles living in the rainforest canopy, could become
extinct before they are even known to science.

The last Red List update, released in May last year, looked at 40,168
species and considered 16,118 to be threatened - including 7,725 animals of
all types (mammals, birds, reptiles, fish, insects etc) and 8,390 plants.

*MICHAEL *

*--------*

*Vision2020 Post: Ted Moffett*
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