ECOLOGIST RAVEN WARNS OF PLANETARY CATASTROPHE
In the past 50 years alone, the population has more than doubled, while soil erosion has
increased by 20 percent, agricultural land has decreased by 20 percent, one-third of the
world's forests have been chopped down, carbon dioxide has increased by one-sixth,
and there's been 7 percent loss of the stratospheric ozone layer.
If the Earth's carrying capacity were a checking account, we'd be overdrawn. Based on
calculations by ecologists William Rees and Hans Wackernagel, it would take 1.2 Earths
to support our current population. The fact that we have only one planet at our disposal
means that large portions of humanity are undernourished.
Some look to development to correct the problem of unequal distribution, assuming that
in time the developing world will reach the standard of living that the developed world
already enjoys, but Rees and Wackernagel's calculations demonstrate the folly of such
belief.
"To support everyone at the standard of the developed countries, we would need three
Earths," Raven said. "To support everyone at current standards if the population doubled
[a milestone we are likely to reach by the mid-21st century] we would need six Earths.
To support double the current population at the standards of the developed countries
would take 12 Earths."
The stress that billions of hungry humans exert on the environment is driving plant and
animal species to extinction at a rate unprecedented since Earth's collision with a giant
asteroid wiped out the dinosaurs. Over Earth's history, the average extinction rate has
been 10 species per year, said Raven. But between 1600 and 1950, it has averaged 100
per year. "Currently, we are losing thousands of species every year and soon it will be
tens of thousands. At this rate, two-thirds of Earth's species will be gone by the year
2100."
Most of these extinctions are the result of habitat destruction, but there are other factors
as well. Overfishing, overgathering of wild herbs for the natural medicine market, the
introduction of alien invasive species, and changes in habitat due to global warming are
all taking their toll.
NATIONAL SURVEY REVEALS BIODIVERSITY CRISIS - SCIENTIFIC EXPERTS
BELIEVE WE ARE IN MIDST OF FASTEST MASS EXTINCTION IN EARTH'S
HISTORY
Crisis Poses Major Threat to Human Survival; Public Unaware of Danger
The American Museum of Natural History and Louis Harris and Associates, Inc.
developed a nationwide survey titled Biodiversity in the Next Millennium. The survey
reveals a startling gap in understanding between the scientific community and the
general public concerning a current crisis in sustaining "biodiversity" - the variety and
interdependence of the Earth's plants and animals.
Seven out of ten biologists believe that we are in the midst of a mass extinction of living
things, and that this dramatic loss of species poses a major threat to human existence in
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the next century. In strong contrast to the fears expressed by scientists, the general
public is relatively unaware of the loss of species and the threats that it poses.
This mass extinction is the fastest in Earth's 4.5-billion-year history and, unlike prior
extinctions, is mainly the result of human activity and not of natural phenomena.
Scientists rate biodiversity loss as a more serious environmental problem than the
depletion of the ozone layer, global warming, or pollution and contamination.
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Scientists believe some of the most important effects of this dramatic species loss are:
Serious impairment of the environment's ability to recover from natural and humaninduced disasters.
Destruction of the natural systems that purify the world's air and water.
Reduction of the potential for the discovery of new medicines.
Increased flooding, drought, and other environmental disasters.
Substantial contribution to the degradation of the world's economies, thereby weakening
the social and political stability of nations across the globe.
QUARTER OF MAMMALS 'FACE EXTINCTION'
Almost a quarter of the world's mammals face extinction within 30 years, according to a
United Nations report on the state of the global environment.
The destruction of habitats and the introduction of alien species from one part of the
world to another are blamed for the threatened loss to biodiversity.
The United Nations Environment Programme (Unep) report is officially published on
Wednesday. It identifies more than 11,000 endangered animal and plant species including more than 1,000 mammals, nearly a quarter of the world's total. One in eight
bird species is also in danger of extinction, and more than 5,000 different plants.
The species likely to vanish within three decades include well-publicized cases such as
the black rhinoceros and the Siberian tiger, and less well-known animals such as the
Philippine eagle and the Asian Amur leopard.
The UN report is a review of the past 30 years in terms of environmental damage.
Based on that assessment, the UN says that all the factors which have led to the
extinction of species in recent decades continue to operate with "ever-increasing
intensity".
The encroachment of human settlement into wilderness regions, rainforest and wetlands
destruction, and the impact of industry, have had a dramatic impact on the survival of
threatened animals and plants.
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Butterflies
Six large sets of data collected over the past 20 to 40 years in England, Wales, and
Scotland were analysed by Jeremy Thomas of the Natural Environment Research
Council Centre for Ecology and Hydrology in Dorchester, UK and colleagues. More than
20,000 volunteers submitted over 15 million records of species.
The researchers found that populations of 71 percent of the butterfly species have
decreased over the last 20 years, compared to 56 percent for birds and 28 percent for
plants. Two butterfly species (3.4 percent of total) became extinct, compared to six (0.4
percent) of the plant species surveyed.
Crucially, the decline in populations happened in all the major ecosystems and was
distributed evenly across Britain, rather than in just a few heavily degraded regions.
Insects
The term "endangered species" typically conjures up images of charismatic animals—
tigers, pandas, orangutans, whales, condors. But a new study says that the vast majority
of species on the verge of extinction is in fact humble insects.
The study estimates that up to 44,000 bugs of all varieties could have been wiped off the
face of the Earth during the last 600 years. And hundreds of thousands more insect
species could be lost over the next 50 years.
The finding is significant, because insects play vital roles in plant pollination,
decomposition, and soil processing. They also form essential links in ecological chains
as plant-eaters, predators, and parasites.
The loss of keystone insect species—those on which a large number of other species
depend—could be especially detrimental for ecosystems and people.
More birds slipping towards extinction
BirdLife International's annual evaluation of how the world’s bird species are faring
shows that the total number considered to be threatened with extinction is now 1,212,
which when combined with the number of near threatened species gives a total of
exactly 2,000 species in trouble – more than a fifth of the planet’s remaining 9,775
species.
Only 10 percent of big ocean fish remain
A new global study concludes that 90 percent of all large fishes have disappeared from
the world's oceans in the past half century, the devastating result of industrial fishing.
The study, which took 10 years to complete and was published in the international
journal Nature this week, paints a grim picture of the Earth's current populations of such
species as sharks, swordfish, tuna and marlin.
The authors used data going back 47 years from nine oceanic and four continental shelf
systems, ranging from the tropics to the Antarctic. Whether off the coast of
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Newfoundland, Canada, or in the Gulf of Thailand, the findings were dire, according to
the authors.
"I think the point is there is nowhere left in the ocean not overfished," said Ransom
Myers, a fisheries biologist at Dalhousie University in Halifax, Nova Scotia and lead
author of the study.
Climate Change Drives Widespread Amphibian Extinctions
Warmer temperatures enhance growth conditions of fatal fungus
Results of a new study provide the first clear proof that global warming is causing
outbreaks of an infectious disease that is wiping out entire frog populations and driving
many species to extinction.
Published in the Jan. 12 issue of the journal Nature, the study reveals how the warming
may alter the dynamics of a skin fungus that is fatal to amphibians. The climate-driven
fungal disease, the author's say, has hundreds of species around the world teetering on
the brink of extinction or has already pushed them into the abyss.
"Disease is the bullet that's killing the frogs," said J. Alan Pounds, the study's lead
scientist affiliated with the Tropical Science Center's Monteverde Cloud Forest Preserve
in Costa Rica. "But climate change is pulling the trigger. Global warming is wreaking
havoc on amphibians, and soon will cause staggering losses of biodiversity," he said.
Lions 'close to extinction'
Lion populations have fallen by almost 90% in the past 20 years, leaving the animal
close to extinction in Africa, a wildlife expert has warned.
There are now only 23,000 left, compared to an estimated 200,000 two decades ago,
according to Laurence Frank, a wildlife biologist from the University of California.
Drawing on a study in Kenya, he says that the only hope for lions and other predators is
for humans and wildlife to live together.
Clare Wallerstein of the International Fund for Wildlife Welfare told the BBC that the
problem would get worse as Kenya's human population doubled in the next 12 years.
Interviewed in New Scientist magazine, Dr Frank says "It's not just lions. Populations of
all African predators are plummeting."
The wild dog population has fallen to between 3,500 and 5,000 and there are now fewer
than 15,000 cheetahs.
"People know about elephants, gorillas and rhinos, but they seem blissfully unaware that
these large carnivores are nearing the brink," he says.
Acid seas kill off coral reefs
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THE world’s coral reefs could disappear within a few decades along with hundreds of
species of plankton and shellfish, according to new studies into man’s impact on the
oceans.
Researchers have found that carbon dioxide, the gas already blamed for causing global
warming, is also raising the acid levels in the sea. The shells of coral and other marine
life dissolve in acid. The process is happening so fast that many such species, including
coral, crabs, oysters and mussels, may become unable to build and repair their shells
and will die out, say the researchers.
“Increased carbon dioxide emissions are making the world’s oceans more acidic and
could cause a mass extinction of marine life similar to the one that occurred on land
when the dinosaurs disappeared,” said Professor Ken Caldeira of the Carnegie
Institution’s global ecology department.
When CO2 produced by burning fossil fuels dissolves in the ocean, it forms carbonic
acid. A little of this can benefit marine life by providing carbonate ions — a vital
constituent in the biochemical process by which sea creatures such as corals and
molluscs build their shells.
Caldeira found, however, that the huge volumes of carbon dioxide being released by
humans are dissolving into the oceans so fast that sea creatures can no longer absorb it.
Consequently, the levels of carbonic acid are rising and the oceans are “turning sour”.
World's reptile populations running thin
Reptiles worldwide may be under greater environmental stress than their amphibian
cousins, according to a report published in today's issue of the journal BioScience.
According to the researchers, government records show that reptiles are vanishing
faster than amphibians.
UN's clarion call for great apes: The clock now stands at one minute to midnight
for the world's four great ape species, the United Nations says.
All the great apes - gorillas, chimpanzees, bonobos (pygmy chimps), and orang-utans face a very high risk of extinction within 50 years at most, the UN says.
It hopes to establish areas where ape populations can stabilise or even grow, if it
manages to raise enough money.
Dr Klaus Toepfer, Unep's executive director, said: "$25 million is the bare minimum we
need, the equivalent of providing a dying man with bread and water.
"The great apes share more than 96% of their DNA with humans. If we lose any great
ape species we will be destroying a bridge to our own origins, and with it part of our own
humanity."
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Unesco says research suggests the western chimpanzee has already disappeared from
Benin, Togo and Gambia, and could soon vanish from another west African country,
Senegal.
There are only about 2-400 chimpanzees left there, slightly more in Ghana, and fewer
than 200 in Guinea-Bissau.
The main threats to all the apes are of human origin: war, poaching, and the live animal
trade.
Human encroachment into the forests is increasing, and outright forest destruction
leaves them no hiding place.
DISCUSSION TOPICS
Positions:
Extinction is a moral issue. Humans have no right to be doing this to other creatures.
Extinction is an aesthetic issue. The loss of biodiversity is a loss of beauty.
Extinction is an economic issue. Destruction of organisms/ecosystems is bound to
impact on future productivity and human health.
Humans are animals, and if our mode of acquiring resources leads to extinctions, that’s
part of how nature works.
The fact that there’s so much biodiversity doesn’t mean it’s necessary; it’s just an
outcome of the way evolution works, and that phase of planetary history is being
supplanted by the human phase.
Since most of biodiversity is now harbored in rainforests in “underdeveloped” countries,
extinctions are a necessary consequence of their understandable “development”
trajectories. Many species were driven to extinction during the “western expansion” in
the US.
We can build a lot of zoos and enjoy biodiversity that way. It doesn’t need to be
sustained in natural settings that most people never visit.
Bottom lines:
It’s inevitable. The planet is going down the tubes. Best to get on with my life and not
think about this stuff because there’s nothing I can do about it.
I intend to do all I can in my lifetime to help turn this situation around.
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