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Extinction Countdown

Extinction Countdown


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Extinction crisis revealed: One fifth of the world’s mammals, birds and amphibians are threatened

The views expressed are those of the author and are not necessarily those of Scientific American.


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One fifth of the world’s vertebrates are threatened with extinction. That’s the word from the 10th Conference of the Parties to the Convention on Biological Diversity this week in Nagoya, Japan, where a team of 174 scientists presented an assessment of the world’s at-risk vertebrate species.

According to the study, published in the October 28 issue of Science, the number of threatened species has grown dramatically in the past four decades, exceeding the normal “background rate” of extinction by a factor of two or three. The IUCN Red List of Threatened Species currently lists 25,780 vertebrates as threatened, and an average of 52 species become more threatened (based on the IUCN’s categories of risk) every year.

“The ‘backbone’ of biodiversity is being eroded,” said Harvard University entomologist Edward O. Wilson in a prepared statement. “One small step up the Red List is one giant leap forward towards extinction. This is just a small window on the global losses currently taking place.”

There is small amount of good news accompanying this study: The wide range of conservation efforts around the world has actually slowed this rate of extinction.

But current conservation efforts are far from adequate. According to a second study, also presented at the conference and published in the same issue of Science, the world would need to spend 10 times as much as it currently does on conservation in order to halt the pending extinction of many species. “There is no question that business-as-usual development pathways will lead to catastrophic biodiversity loss,” said one of the second study’s lead authors, Paul Leadley of the University of Paris–Sud, in a prepared statement. “Even optimistic scenarios for this century consistently predict extinctions and shrinking populations of many species.”

The authors point out that all changes in species population size and distribution matter, as they reflect the health and well-being of the dominant species on the planet: humans. If species are dying out, it is an indication of the long-term health of our own species, and we need to be aware of the impact we are having on our own ecosystem.

Photo: Endangered bonobo (Pan paniscus) via Wikipedia





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  1. 1. dbtinc 4:20 pm 10/27/2010

    Interesting observation but somehow it avoids the complexities of evolution. The author appears to be using OFAT (One factor at a time) rather then looking at the loss of species in the context of a "design of experiments."

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  2. 2. jtdwyer 1:57 am 10/28/2010

    Its unfortunate that the researchers apparently did not recognize the causal relationship between human overpopulation, continued population growth, increasing consumption of resources (including habitat land) and the extinction of other species. It would seem almost impossible to overlook…

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  3. 3. HowardB 1:45 pm 10/28/2010

    We humans are the result of climate change, environment change and … change in general. Yes. If the climate and geological state of the earth had not kept changing and if other animals had not been made extinct along the way HUMAN BEINGS would not have evolved into what we are now.

    Change is the most natural thing in the world. Species evolve and species die. The same is true for all kinds of things in our lives. We need to grasp this concept of change and embrace and understand it.

    We cannot freeze our environment in a state of no-change. It is totally unnatural and totally unrealistic. There appears to have grown a new kind of obsession in recent decades, an obsession that the Earth should be kept exactly like it is. No change should be welcomed. No change should remain un tackled. No change!

    Change is natural. Change is normal. Extinction is normal.

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  4. 4. rocketlauncher 4:39 pm 10/28/2010

    Your point about ‘change’ seems irrelevant to me.

    Who is saying that we need to freeze the environment into a state of no-change? That would be ridiculous.

    The point is that there are repercussions to our actions and we can choose to do things that change things for the better or the worse.

    Anthropogenic causes for species extinctions and environmental ‘changes’ are very obvious. Why would we want to allow all these things to happen if we have the ability to prevent them?

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  5. 5. jtdwyer 5:29 pm 10/28/2010

    I’m sure HowardB can defend himself, but I agree with him that our concerns about the loss of species is driven by our perception of a ‘normal’ state in which there is no change. While many other species are threatened by our overpopulation, as we will soon be ourselves, species come and go. It’s very difficult to assess. It is probably a source for concern that so many species are threatened, but if humanity could only stabilize our impact on the environment, even if 20% of all species went extinct many new species would likely find an environmental niche in which they could survive and flourish.

    IMO, that presumes that the effects of our activities, and the momentum of effects already in progress, do not extinguish many more species, including our own. At this moment humanity must concern itself with the root cause of the majority of the world’s problems: overpopulation. If we can’t successfully address it and, indirectly, the issues it produces there’s little point in our saving the orchids.

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  6. 6. HowardB 6:10 pm 10/28/2010

    rocketlauncher wrote: "Who is saying that we need to freeze the environment into a state of no-change? That would be ridiculous."

    Then why is there so much being written and hyped about species going extinct ? What is the problem ? Why should we alter our way of life because a couple of species goes extinct ? this is the way of the world, the way of nature. The human species is influencing others. And while those species go away others will fill their place and new species will evolve over time.

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  7. 7. HowardB 6:14 pm 10/28/2010

    jtdwyer you are correct. It is a matter of perspective. There is no perspective in the hyperbole of the Natural Sciences publicity machine. There are many problems facing Humanity. As you say over population, also energy, pollution, poverty and suffering.
    I don’t disagree with all attempts to preserve some species. But again it is a matter of proportion and perspective. Major animal species like the Lion, the Elephant, etc are important to our human history and culture. But we have to accept that others are remotely relevant and we have to prioritise while also allowing Nature to take it’s course.
    If Man was not on the Earth there would be regular extinctions. It is the way of the Universe.

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  8. 8. jtdwyer 8:06 pm 10/28/2010

    I agree, but also think that human population growth is a critical factor contributing to energy, pollution, global warming, poverty, suffering, and essentially all problems facing the world. I was born in 1950; soon the world population will have tripled since that time. The problem seems obvious to me, no not so much to younger people.

    I think that if the population could somehow be humanely reduced by 30%, many of the rest of the world’s problems would be similarly diminished. It could already take hundreds of years for the climate to stabilize, however…

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  9. 9. rocketlauncher 12:12 pm 10/29/2010

    Yes, it seems that one of the most significant underlying causes of these issues is overpopulation. Things are getting out out of balance. Continued growth at these exponentially increasing rates seems obviously unsustainable to me.

    Problem is finding a practical way to deal with it. Look at the world population curve and where it is headed just in the next few decades – very scary.

    Things have been tried, like china’s policies for children with some success, but tons of dough has been put into everything from education, to sterilization (which is never going to be accepted freely) and even condom distribution and it’s not working.

    Is there even a solution that doesn’t involve killing, war, starvation, or worse?

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  10. 10. rocketlauncher 12:18 pm 10/29/2010

    Here are some of the problems:

    1) Lost opportunities to discover potentially life saving drugs as plant species are gone forever.

    2) Ecosystems can lose their resilience to change and can therefore deteriorate faster if less species exist

    3) Domino effect of losing key elements of a food chain can accelerate loss, maybe to some tipping point where even though the earth may recover, it would be grealy diminished in life support and quality of the life it can support

    There are others too, but I don’t wat to write a long essay here. My point is that sure this is all natural, but we have the power to influence the outcome for the better. Why not at least try?

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  11. 11. jtdwyer 3:26 pm 10/29/2010

    Very good points. Who can object to addressing these issues? I only point out that the root cause is human overpopulation producing loss of habitat and other necessary resources.

    As you point out, the difficulty is in effectively addressing overpopulation. Nature will address the issue in its own way if we cannot do so humanely, with starvation, war, pestilence, etc., without regard to human suffering.

    I think the consideration of radical approaches is necessary such as enforcing a one child per person limit, legalizing euthanasia, etc… Otherwise I’m afraid my living grandchildren, their progeny and billions of others will suffer greatly.

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  12. 12. HowardB 6:53 pm 10/29/2010

    1) Lost opportunities to discover potentially life saving drugs as plant species are gone forever.

    + There are billions of species of life on this earth. The chances of finding an important drug for a specific species is billions to one. This is not a serious reason to devote major resources to preventing all extinction.

    2) Ecosystems can lose their resilience to change and can therefore deteriorate faster if less species exist.

    + Natural ecosystems evolve and when one species disappears it does so slowly and another takes it’s place while others evolve to cope. That is hat evolution is about.

    3) Domino effect of losing key elements of a food chain can accelerate loss, maybe to some tipping point where even though the earth may recover, it would be grealy diminished in life support and quality of the life it can support

    + Again this is what evolution is all about. There is no justification for human beings trying to freeze nature and prevent happening what has been happening on our planet for billions of years. It makes no sense.

    Where specific species of specific known value are concerned there is justification in making an effort. But that depends on the scale of the effort. The Natural Scientists who constantly blow this trumpet of extinction disaster don’t apply any perspective or proportionality to this issue and they demand we change the way we live on the planet for each and every extinction. This is way too far to go simply to stop extinction of some rare species of unknown value and unknown significance.

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  13. 13. ACTORwriter 10:48 am 11/18/2010

    It seems to me that most often there are multiple benefits which give rise to (and even promote) various evolutionary traits, physical skills and physiological facilities. For example, we might deduce that the development of hands and hand-like structures allowed for muscled grasping with hands safe-guarded against fatal falls, etc. But we might also postulate that hands and finger structures engendered tool-making; AND the ability to quickly clear away eye debris (such as dust or other obstruction particles) thereby preventing fatalities from predators or from prey, as well as the ability to allow food-gathering predation, since after all, clear eyesight must have been vital in those efforts and enterprises. Additionally, hands surely added intricacy ability (and still do so) in tool-making whether for weapons or for other myriad life-supporting activities. Thus, while a single catastrophic event such as an asteroid impact, or fatal bacterial infection, might spell doom and extinction for a species, more often, as with evolutionary development, more than one cause is the generation for the elimination of a species (in much the same way that a multiplicity of life preservation events might produce any physiological structure.

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  14. 14. ACTORwriter 10:48 am 11/18/2010

    It seems to me that most often there are multiple benefits which give rise to (and even promote) various evolutionary traits, physical skills and physiological facilities. For example, we might deduce that the development of hands and hand-like structures allowed for muscled grasping with hands safe-guarded against fatal falls, etc. But we might also postulate that hands and finger structures engendered tool-making; AND the ability to quickly clear away eye debris (such as dust or other obstruction particles) thereby preventing fatalities from predators or from prey, as well as the ability to allow food-gathering predation, since after all, clear eyesight must have been vital in those efforts and enterprises. Additionally, hands surely added intricacy ability (and still do so) in tool-making whether for weapons or for other myriad life-supporting activities. Thus, while a single catastrophic event such as an asteroid impact, or fatal bacterial infection, might spell doom and extinction for a species, more often, as with evolutionary development, more than one cause is the generation for the elimination of a species (in much the same way that a multiplicity of life preservation events might produce any physiological structure.

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  15. 15. timbo555 11:36 pm 12/5/2010

    Twenty percent of the world’s species are not even close to being extinct. There are some scientists who propose that they are threatened with extinction. To what extent these claims are highly exaggerated and politically motivated has yet to be seen.

    Some areas of life sciences in general and environmental science in particular have become so terribly politicised that it becomes difficult to believe anything that is said by the people who speak for those disciplines. This magazine has become a shill for the alarmist left. Scientific integrity left the building a long time ago.

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