ECOLOGY
ENVIRONMENTAL ISSUES
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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the rate of extinction is much faster than ever before
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there is no such thing as extinction in the 21st century
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now we can record when it happens
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the rate of extinction is much slower than ever before
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Detailed explanation-1: -Intensifying pressure on biodiversity The main direct causes of extinction are loss and degradation of habitats due to human use of land and sea; overexploitation of wild populations; and the impacts on populations and ecological communities of invasive alien species, pollution, and climate change14, 16 and 17.
Detailed explanation-2: -Regardless, scientists agree that today’s extinction rate is hundreds, or even thousands, of times higher than the natural baseline rate. Judging from the fossil record, the baseline extinction rate is about one species per every one million species per year.
Detailed explanation-3: -“When you lose one species, it affects the ecosystem and everything around it gets a little bit more fragile while it adapts to change, ” said Kelsey Wooddell, assistant director of the Earth Institute Center for Environmental Sustainability.
Detailed explanation-4: -These experts calculate that between 0.01 and 0.1% of all species will become extinct each year. If the low estimate of the number of species out there is true-i.e. that there are around 2 million different species on our planet**-then that means between 200 and 2, 000 extinctions occur every year.