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AuroraGlacialis
10-28-2010, 04:23 AM
The paper highlights that the percentage of species threatened among vertebrates ranges from 13% of birds to 41% of amphibians. Although the study focused on vertebrates, it also reports on the levels of threat among several other groups assessed for the IUCN Red List, including14% of seagrasses, 32% of freshwater crayfish, and 33% of reef-building corals.
(from Nature's backbone at risk: World's vertebrates face an extinction crisis, assessment finds (http://www.sciencedaily.com/releases/2010/10/101026184159.htm) , referencing to Science, 2010; DOI: 10.1126/science.1194442)

The article describes the current status of the ongoing anthropogenetic mass extinction. The study is a review, looking at the works of way over 100 authors, but focuses mostly on vertebrates. For these, they found that conservation efforts work, but only improved the status of 9% of the endangered species with the numbers of species entering that status beeing way higher. Also, I think the study shows, that because of the effectiveness of conservation efforts for specific families (like birds & mammals), one should be careful using these numbers to predict global extinction rates. People might be able to protect local bird species in England or endangered hamsters in Germany, reducing the loss of biodiversity in these countries, but the same may not be true for worms or insects in some other country. Science knows only a fraction of the species of the planet and describes only the losses and conservation efforts in that fraction. I think this means, that the number could even underestimate the total biodiversity loss if people do not take into account the limited and localized effect of conservation efforts.

In any case, from the numbers above, a third (for some families even much more) of the species on the planet are threatened by extinction. This rivals by far the famous "meteorite that wiped out the dinosaurs"!

Suzy
10-28-2010, 09:46 PM
A related article from 2007: "Animal Extinction - the greatest threat to mankind (http://www.independent.co.uk/environment/animal-extinction--the-greatest-threat-to-mankind-397939.html)"

AuroraGlacialis
10-29-2010, 03:19 AM
Yeah - it is horrifying to think that it takes millions of years to restore biodiversity that is now wiped off the earth in mere decades. If this is not stopped now, our descendants will simply not have a biodiverse ecosphere. Maybe they can restore with some genetic technology a few of the extinct species that are loved and that are known, but not the 100 times as many unknown species, especially in less adorable families like worms, insects, funghi. Some of these dont even appear significantly in studies at all. It's a ludricrous idea to try to store all the genetic data of all species on earth for "future restoration" - the effort just to find and describe these species is humongous, even if the DNA sequencing becomes faster.
One sad thing about the article you linked is, that it digs on earhy humans beeing already as destructive as modern ones, just on a different scale. I dont think that this is entiretly true. For once, I doubt that ancient humans have really wiped out megafauna at the end of the glaciation period (there is evidence that a global climate change from ice age to interglacial is quite capable of doing that for a few species). What I dont like about that statement is, that it makes humans look inherently destructive. Yes, they are a predator and they will change the ecosystem they enter, so would lion introduced to an island that has no predator or rabiits to Australia or Kudzu to the US (the latter are recent examples of invasive species). But that is hardly compareable to global massive extinction especially of non-food species. A lion as well as ancient humans hunt down their food supply animals until they may be threatened or even extinct. But they dont eradicate species to replace them by others or eradicate them as a byproduct of their life. modern humans dont eat salamander or worms or root funghi or panda bears - this is completely differnt from ancient humans hunting mammoth to have food. In modern times, animals go extinct so humans can have toilet paper, television, cars, cellphones and bottled water.