EVOLUTION
EVIDENCE FOR EVOLUTION
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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They occur instananeous
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They are usually on the scale of a few years
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They are always on the scale of hundreds to thousands of years
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They can occur over shorter or longer time scales
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Detailed explanation-1: -Mass extinctions are episodes in which a large number of plant and animal species become extinct within a relatively short period of geologic time-from possibly a few thousand to a few million years.
Detailed explanation-2: -What causes mass extinctions? Past mass extinctions were caused by extreme temperature changes, rising or falling sea levels and catastrophic, one-off events like a huge volcano erupting or an asteroid hitting Earth. We know about them because we can see how life has changed in the fossil record.
Detailed explanation-3: -These are called mass extinctions, when huge numbers of species disappear in a relatively short period of time. Paleontologists know about these extinctions from remains of organisms with durable skeletons that fossilized.