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Name: marge
Status: N/A
Age: N/A
Location: N/A
Country: N/A
Date: Around 1993


Question:
About how many endangered species are there?



Replies:
"Endangered" species are often defined legally, so if a species is on the verge of extinction; it may not be considered endangered unless someone complains about this. As our rain forests are destroyed at 100's of acres per minute, many species are going extinct, perhaps even before they have even been discovered by humans. I will try to see if i can find out how many are now considered endangered. I just finished reading Last Chance to See by Douglas Adams. He described his experience with seeing endangered species, before they went extinct. I recommend it. There are about 1.4 million described species of living things. About 1 million described animal species. But it has been estimated that there are 10-100 million left to be discovered. Extinction rates for the last few million years has been about 1 species lost per century. But since human populations have exploded, extinction rates have been accelerating. Most extinctions within human history have occurred in the last 300 years (the "industrial revolution"). Most of the extinctions in the last 300 years have occurred in the last 50. And most of the extinctions of the last 50 years have occurred in the last 10.

Now extinction rates are around 1000's of species per year (that is a 100,000 times increase over the last 5000 years!). We are in the midst of a mass extinction, the likes of which has not been seen in 100's of millions of years! Much of these are thought to be due to human influence. Currently, there are about 5200 threatened animal species, and about 17,300 threatened plant species. The saddest part perhaps being that we will never know how many species humans caused to go extinct, and will certainly cause the extinction of thousands of species, without ever having seen the organisms, and without ever firing a gunshot. Habitat destruction is one of the most effective ways of reducing the number of species in an area. If you want to see how to kill lots of fascinating species, go to one of the tropical islands, like Hawaii. According to a pamphlet called Endangered Species from the U. S. Department of the Interior, more than 600 spp. of life were either endangered or threatened in the U. S. as of 1991. Another 500 spp. were listed from outside the U. S. About 50 to 100 spp. are added each year and there are thousands of species that are thought to be in danger but there is not enough data to prove it.

Jim Murray



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