Since the last summary of the world's mammals was published in 2005, giving Linnaean tags to roughly 5,400 mammalian species then known, some 400 or so new species have been discovered.
Humanity doesn't need a moon-base or a manned trip to Mars, says Harvard’s E.O. Wilson, evolutionary biologist and author of The Creation, “We need an
expedition to planet Earth, where probably fewer than 10 per cent of
species are known to science, and fewer than 1 per cent of those have
been studied beyond a simple anatomical description and a few notes on
natural history. At the same time, we are engaged in a genocide against
those species, known and unknown; the sixth mass extinction has begun.”
In an interview with Natalie Angier of the New York Times, John Robinson, an executive vice president at the Wildlife Conservation Society observed that “we've only described an estimated 15 percent of all species on Earth, so most of what's going extinct are things we didn't even know existed." In addition are the known species that we've managed to directly or indirectly annihilate, like the Yangtze river dolphin (image above), declared functionally extinct two years ago, or the dusky seaside sparrow, which gave its last flutter in 1987.
Experts say that at least half of the world's current species will be completely gone by the end of the century. Most biologists say that we are in the midst of an anthropogenic mass extinction. Numerous scientific studies confirm that this phenomenon is real and happening right now. Should anyone really care? Will it impact individuals on a personal level? Scientists say, "Yes!
Critics argue that species disappear and new ones emerge all the time. That's true, if you're speaking in terms of millennia. Scientists acknowledge that species disappear at an estimated rate of one species per million per year, with new species replacing the lost ones at around the same rate. Recently humans have accelerated the extinction rate to where several entire species are annihilated every single day. The death toll artificially caused by humans is mind-boggling. Nature will take millions of years to repair what we destroy in just a few decades.
One analysis, published in the journal Nature, shows that it takes 10 million years before biological diversity even begins to approach what existed before a die-off. Over 10,000 scientists in the World Conservation Union have compiled data showing that currently 51 per cent of known reptiles, 52 per cent of known insects, and 73 per cent of known flowering plants are in danger along with many mammals, birds and amphibians. It is likely that some species will become extinct before they are even discovered, before any medicinal use or other important features can be assessed. The cliché movie plot where the cure for cancer is about to be annihilated is more real than anyone would like to imagine.
Research done by the American Museum of Natural History found that the vast majority of biologists believe that mass extinction poses a colossal threat to human existence, and is even more serious of an environmental problem than one of its contributors- global warming. The research also found that the average person woefully underestimates the dangers of mass extinction. Powerful industrial lobbies would like people to believe that we can survive while other species are quickly and quietly dying off. Irresponsible governments and businesses would have people believe that we don't need a healthy planet to survive- even while human cancer rates are tripling every decade.
Posted by Casey Kazan with Rebecca Sato.
Sources:
http://www.nytimes.com/2009/07/26/weekinreview/26angier.html?_r=1&ref=science
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