ECOLOGY
BIODIVERSITY AND ITS CONSERVATION
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Lower
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Higher
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Either A or B
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None of the above
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Detailed explanation-1: -Extinctions are about 1, 000 times more frequent now than in the 60 million years before people came along.
Detailed explanation-2: -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-3: -Extinction Rates 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-4: -Modern rates of vertebrate extinction were much higher than a background extinction rate of 2 E/MSY.
Detailed explanation-5: -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.